JP6995339B2 - Power estimator, wireless communication system with it, program and data structure to be executed by a computer - Google Patents

Description

The present invention relates to a power estimator, a wireless communication system including the power estimator, a program for causing a computer to execute, and a data structure.

Research is being conducted to newly create the frequency band required for the 5th generation mobile communication system by sharing the frequency with respect to the frequency band of 6 GHz or less suitable for mobile communication.

As a part of this, mobile terminals that are already distributed in a wide area are used as monitor terminals, and the received power of radio waves in the existing system for each location is obtained from the acquired information on the position of the monitor terminals and the received power of radio waves, and these are analyzed. By doing so, research is proceeding with a focus on mobile dispersion monitoring, which determines the conditions for frequency sharing.

In mobile distribution monitoring, the distribution of monitor terminals varies, so it is necessary to estimate the received power in places where monitor terminals do not exist from the received power in the surrounding area.

As a method for estimating the received power, a contour line of the received power is created from the monitor information (information on the position of the monitor terminal and the received power of the radio wave) acquired by the monitor terminal, and the received power for each location is created from the created contour line of the received power. Can be considered.

Conventionally, the method described in Non-Patent Document 1 is known as a method for creating contour lines of received power. The method for creating contour lines of received power described in Non-Patent Document 1 creates a vector of received power based on two received powers in two monitor terminals, and creates a gradient curve orthogonal to the created vector. This is a method of creating contour lines of received power.

Further, a method described in Non-Patent Document 2 is known as a method of compensating for the accuracy of received power reduced due to fading or the like on the terminal device side.

In this method, when the periodicity of the signal is known, the periodicity of the actually received received signal and the known received signal when affected by fading or the like are compared, and the received power reduced by fading or the like is compared. It compensates for the accuracy of.

Further, in this method, when the signal format is known, fading or the like is performed based on the fact that the signal format actually received and the known received signal when affected by fading or the like match. This compensates for the reduced accuracy of the received power.

Yunhao Liu and Mo Li, “Iso-Map: Energy Efficient Contour Mapping in Wireless Sensor Networks,” Proc. In ICDCS2007, 2007. Tecfik Yucek and Huseyin Arslan, “A Survey of Spectrum Sensing Algorithms for Cognitive Radio Applications,” IEEE Communications Surveys & Tutorials, vol. 11, no.1, 2009.

However, the method for creating contour lines of received power described in Non-Patent Document 1 has a problem that the accuracy of contour lines of received power is lowered when the measured received power is affected by fading.

Further, the method of compensating for the accuracy of the received power described in Non-Patent Document 2 has a problem that complicated calculation processing is required on the monitor terminal side.

Therefore, according to the embodiment of the present invention, there is provided a power estimation device capable of easily creating contour lines of received power by suppressing the influence of fading and the like.

Further, according to the embodiment of the present invention, there is provided a wireless communication system including a power estimation device capable of easily creating contour lines of received power by suppressing the influence of fading and the like.

Further, according to the embodiment of the present invention, there is provided a program for suppressing the influence of fading and the like and causing a computer to easily create contour lines of received power.

Further, according to the embodiment of the present invention, there is provided a data structure capable of easily creating contour lines of received power by suppressing the influence of fading and the like.

According to the embodiment of the present invention, the power estimation device has a shared frequency shared by a plurality of terminal devices for wireless communication among a plurality of frequencies used for wireless communication in a target area for estimating the received power of radio waves. It is a power estimation device that creates contour lines of the received power of radio waves, and includes an extraction means and a creation means. The extraction means is k (which is transmitted from a plurality of terminal devices and includes the maximum value of the received power from a plurality of monitor information including the position information indicating the position of the terminal device and the received power of the radio wave in the terminal device. k is an integer of 2 or more) and extracts monitor information. The creating means obtains the average of the positions of the k terminal devices weighted by the received power based on the k monitor information extracted by the extracting means as the center of gravity of the received power, and out of the k received powers. The maximum distance is the distance between the terminal device that has received power equal to or higher than the power value at the contour line of the received power to be created and is located farthest from the center of gravity of the received power and the center of gravity of the received power. The first contour line having a circular shape centered on the center of gravity of the received power and having the maximum distance as the radius, and the second having an elliptical shape centered on the center of gravity of the received power and having the maximum distance as the major axis. One of the contour lines and the third contour line having a polygonal shape centered on the center point of the received power and having the maximum distance as the distance from the center to one apex is used as the contour line of the received power to be created. Perform the contour line creation process to be created.

When the center of gravity of the received power is obtained, the power estimation device according to the embodiment of the present invention should be created by excluding the received power less than the power value in the contour line of the received power to be created from the k received powers. The maximum distance is determined using the received power equal to or higher than the power value in the received power contour line, and the received power contour line is created. As a result, when the received power less than the power value in the contour line of the received power to be created is affected by fading, the received power affected by fading is not used to obtain the maximum distance.

Therefore, it is possible to suppress the influence of fading and create contour lines of received power.

Preferably, the power estimation device further comprises an estimation means. The estimation means estimates the received power of the radio wave at a desired place in the target area based on the contour lines of the received power created by the creating means.

The estimation means estimates the received power of the radio wave at a desired place in the target area based on the created contour lines of the received power.

Therefore, the received power of the radio wave at a desired place in the target area can be accurately estimated. As a result, it is possible to accurately determine the communication conditions when the terminal device existing in the target area performs wireless communication.

Preferably, the extraction means obtains k new monitor information while removing at least the maximum value of the received power already extracted from the plurality of monitor information until the received power equal to or higher than the contour line power value of the received power to be created is exhausted. Repeat the extraction. Each time the extraction means extracts new k monitor information, the creating means performs contour line creation processing based on the extracted new k monitor information.

Since the creating means creates contour lines of received power based on k monitor information extracted while excluding at least the maximum value of received power already extracted, at least a plurality of received powers collected from a plurality of terminal devices are created. The contour lines of the received power are created in descending order of the received power.

Therefore, it is possible to create contour lines of received power centered on the vicinity of the wave source position.

Preferably, the extraction means is included in the first extraction method for extracting new k monitor information while removing the already extracted k monitor information from the plurality of monitor information, or in the already extracted k monitor information. Using the second extraction method to extract k new monitor information while removing only the maximum value of the received power received, multiple monitors until there is no more received power than the contour line power value of the received power to be created. Repeatedly extract k new monitor information from the information. The creation means includes a first contour line creation process that performs a contour line creation process based on the new k monitor information when the extraction means extracts new k monitor information by the first extraction method, and a new one. The center of gravity of the received power is obtained based on the k monitor information, and the monitor information included in both the already extracted k monitor information and the new k monitor information and the new k monitor information. And, one of the second contour line creation processes for creating the contour lines of the received power by finding the maximum distance based on the center of gravity of the received power is performed every time k new monitor information is extracted. When the extraction means extracts new k monitor information by the second extraction method, the first contour line creation process is performed every time the new k monitor information is extracted.

Therefore, it is possible to create contour lines of received power by changing the extraction method of k monitor information and the processing method of contour line creation processing.

Preferably, the method in which the extraction means extracts new k pieces of monitor information by the first extraction method and the creation means performs the first contour line creation process is the first method, and the extraction means is the first method. The second method is a method in which k new monitor information is extracted by the extraction method and the creation means performs the second contour line creation process, and the extraction means is the new k monitors by the second extraction method. When the method of extracting information and performing the first contour line creation process by the creating means is the third method, the contour lines of the received power use the first method when the calculation amount is set to the minimum. If it is created and the complexity is set to be the second smallest, it is created using the second method, and if the complexity is allowed to be the maximum, the third method is used. Will be created.

When creating contour lines of received power using the first method, the amount of calculation is the smallest, and when creating contour lines of received power using the second method, the amount of calculation is the second smallest, and the third method. When creating contour lines of received power using the method of, the amount of calculation is the largest.

Therefore, it is possible to create contour lines of received power by changing the amount of calculation. In addition, contour lines of received power can be created according to the allowable amount of calculation.

Preferably, the extraction means extracts k pieces of monitor information so that each received power satisfies the reliability rate required according to the radio wave environment.

The creation means creates contour lines of received power based on reliable monitor information.

Therefore, contour lines of received power can be created with high accuracy.

Preferably, the creating means sets the power reduction distance of the radio wave propagation model so that the received power becomes a desired power value lower than the power value on the contour line of the received power already created in the region below the reception sensitivity of the radio wave in the terminal device. Create a contour line that is separated from the already created contour line of the received power by the power reduction distance and has a shape similar to the contour line of the already created received power as the contour line of the received power in the region below the reception sensitivity of the radio wave. ..

In the region below the reception sensitivity of radio waves in the terminal device, the contour lines of the received power can be accurately created, and the contour lines of the received power can be created by reducing the processing amount.

Further, according to the embodiment of the present invention, the wireless communication system includes the power estimation device according to any one of claims 1 to 7.

In a wireless communication system, it is possible to suppress the influence of fading and create contour lines of received power.

Further, according to the embodiment of the present invention, the program has a shared frequency shared by a plurality of terminal devices for wireless communication among a plurality of frequencies used for wireless communication in a target area for estimating received power of radio waves. A program for causing a computer to create contour lines of the received power of radio waves, in which extraction means are transmitted from a plurality of terminal devices, and each of them has position information indicating the position of the terminal device and radio waves in the terminal device. In the first step, k (k is an integer of 2 or more) including the maximum value of the received power is extracted from a plurality of monitor information including the received power, and the creating means is in the first step. The average of the positions of the k terminal devices weighted by the received power based on the extracted k monitor information is obtained as the center of gravity of the received power, and of the k received powers, the received power to be created is calculated. The distance between the terminal device that has received power equal to or higher than the power value on the contour line and is located farthest from the center of gravity of the received power and the center of gravity of the received power is calculated as the maximum distance, and the center of the received power is the center. The first contour line having a circular shape with the maximum distance as the radius, the second contour line having an elliptical shape centered on the center of gravity of the received power and having the major axis of the maximum distance, and the center of gravity of the received power. Performs contour line creation processing to create any of the third contour lines having a polygonal shape centered on the point and the maximum distance as the distance from the center to one apex as the contour line of the received power to be created. It is a program for making a computer execute the second step.

By causing the computer to execute the first step and the second step by the program according to the embodiment of the present invention, the received power less than the power value in the contour line of the received power to be created is excluded from the k received powers. The maximum distance is determined using the received power equal to or higher than the power value in the contour line of the received power to be created, and the contour line of the received power is created. As a result, when the received power less than the power value in the contour line of the received power to be created is affected by fading, the received power affected by fading is not used to obtain the maximum distance.

Therefore, it is possible to suppress the influence of fading and create contour lines of received power.

Preferably, the program causes the estimation means to further perform a third step of estimating the received power of the radio wave at a desired location in the target area based on the contour lines of the received power created in the second step. ..

By letting the computer perform the third step by the program, the estimation means estimates the received power of the radio wave at a desired location in the target area based on the created contour lines of the received power.

Therefore, the received power of the radio wave at a desired place in the target area can be accurately estimated. As a result, it is possible to accurately determine the communication conditions when the terminal device existing in the target area performs wireless communication.

Preferably, the extraction means is new, excluding at least the maximum value of the received power already extracted from the plurality of monitor information until there is no more received power than the contour line power value of the received power to be created in the first step. Extracting k monitor information is repeated. In the second step, each time the extraction means extracts new k monitor information, the creating means performs contour line creation processing based on the extracted new k monitor information.

Since the creating means creates contour lines of received power based on k monitor information extracted while excluding at least the maximum value of received power already extracted, at least a plurality of received powers collected from a plurality of terminal devices are created. The contour lines of the received power are created in descending order of the received power.

Therefore, it is possible to create contour lines of received power centered on the vicinity of the wave source position.

Preferably, the extraction means is a first extraction method for extracting the new k monitor information while removing the already extracted k monitor information from the plurality of monitor information, or the already extracted k monitor information. Using the second extraction method that extracts k new monitor information while removing only the maximum value of the received power included, a plurality of received powers until there is no more received power than the contour line power value of the received power to be created. K new monitor information is repeatedly extracted from the monitor information of. In the second step, when the extraction means extracts new k monitor information by the first extraction method, the creation means performs the contour line creation process based on the new k monitor information. The creation process and the center of gravity of the received power are obtained based on the new k monitor information, and the monitor information included in both the already extracted k monitor information and the new k monitor information, and the new monitor information. The new k monitor information extracts one of the k monitor information and the second contour line creation process that creates the contour line of the received power by finding the maximum distance based on the center point of the received power. When the extraction means extracts new k monitor information by the second extraction method, the first contour line creation process is performed every time the new k monitor information is extracted.

Therefore, it is possible to create contour lines of received power by changing the extraction method of k monitor information and the processing method of contour line creation processing.

Preferably, the method in which the extraction means extracts new k pieces of monitor information by the first extraction method and the creation means performs the first contour line creation process is the first method, and the extraction means is the first method. The second method is a method in which k new monitor information is extracted by the extraction method and the creation means performs the second contour line creation process, and the extraction means is the new k monitors by the second extraction method. When the method of extracting information and performing the first contour line creation process by the creating means is the third method, the contour lines of the received power use the first method when the calculation amount is set to the minimum. If it is created and the complexity is set to be the second smallest, it is created using the second method, and if the complexity is allowed to be the maximum, the third method is used. Will be created.

When creating contour lines of received power using the first method, the amount of calculation is the smallest, and when creating contour lines of received power using the second method, the amount of calculation is the second smallest, and the third method. When creating contour lines of received power using the method of, the amount of calculation is the largest.

Therefore, it is possible to create contour lines of received power by changing the amount of calculation of the computer. In addition, contour lines of received power can be created according to the allowable computational complexity of the computer.

Preferably, in the first step, the extraction means extracts k pieces of monitor information so that each received power satisfies the reliability rate required according to the radio wave environment.

The creation means creates contour lines of received power based on reliable monitor information.

Therefore, contour lines of received power can be created with high accuracy.

Preferably, in the second step, the creating means reduces the received power so that the received power becomes lower by a desired power value than the power value on the contour line of the already created received power in the region below the reception sensitivity of the radio wave in the terminal device. The distance is obtained based on the propagation model of the radio wave, and the contour line that is separated from the already created contour line of the received power by the power decrease distance and has a shape similar to the contour line of the already created received power is received in the region below the reception sensitivity of the radio wave. Create as a contour line of electric power.

In the region below the reception sensitivity of radio waves in the terminal device, the contour lines of the received power can be accurately created, and the contour lines of the received power can be created by reducing the processing amount of the computer.

Further, according to the embodiment of the present invention, the data structure is a data structure including a plurality of monitor information, and each of the plurality of monitor information includes the position information indicating the position of the terminal device and the terminal device wirelessly. It has a structure in which a shared frequency shared for communication and a received power of a radio wave detected by a terminal device are associated with each other. Of the plurality of received powers included in the plurality of monitor information, k (k is an integer of 2 or more) monitor information including the maximum value of the received power is extracted from the plurality of monitor information by the extraction means. The k monitor information extracted by the extraction means is used by the creating means to obtain the center of gravity point of the received power, which is the average of the positions of the k terminal devices weighted by the received power. Of the k received powers included in the k monitor information extracted by the extraction means, the received power that is equal to or greater than the power value of the received power to be created on the contour line and the received power that is greater than or equal to the power value of the received power on the contour line are supported. The attached position information is used by the creating means to obtain the maximum distance, which is the distance between the terminal device located at the position farthest from the center of gravity of the received power and the center of gravity of the received power. The maximum distance determined by the creating means is used by the creating means to create any of the first contour lines, the second contour lines and the third contour lines. The first contour line has a circular shape centered on the center of gravity of the received power and has a radius of the maximum distance, and the second contour line has a major axis centered on the center of gravity of the received power and the maximum distance. The third contour line has a polygonal shape centered on the center of gravity of the received power and the maximum distance is the distance from the center to one apex.

By using the data structure according to the embodiment of the present invention, the power estimation device obtains the center of gravity of the received power, and finds that the received power is less than the power value in the contour line of the received power to be created among the k received powers. Is excluded, and the maximum distance is determined using the received power that is equal to or greater than the power value in the contour line of the received power to be created, and the contour line of the received power is created. As a result, when the received power less than the power value in the contour line of the received power to be created is affected by fading, the received power affected by fading is not used to obtain the maximum distance. Therefore, it is possible to suppress the influence of fading and create contour lines of received power. Further, by using the data structure according to the embodiment of the present invention, the CPU that executes the program according to the embodiment of the present invention described above creates contour lines of received power in the same manner as the power estimation device. Therefore, the same effect can be obtained.

Further, according to the embodiment of the present invention, the data structure is a position indicating a shared frequency shared by k (k is an integer of 2 or more) terminal devices for wireless communication and a center position of contour lines of received power. It is a data structure having a structure in which information, a power value of contour lines, and a radius of contour lines are mutually associated with each other, and position information is k pieces included in k pieces of monitor information received from k pieces of terminal devices. It consists of the center of gravity of the received power, which is the result of the creation means calculating the average of the positions of the k terminal devices weighted by the received power based on the received power of the k terminal devices and the position information of the k terminal devices. , The radius of the contour line has the received power equal to or higher than the power value in the contour line of the received power to be created among the k received powers, and is received with the terminal device located at the position farthest from the center of gravity of the received power. It consists of the maximum distance obtained by calculating the distance from the center of gravity of the electric power by the creating means, and the electric power value of the contour line is the electric power value of the radio wave having a shared frequency, and is the electric power value detected by the creating means.

By using the data structure according to the embodiment of the present invention, it is possible to accurately estimate the power value of the radio wave at a desired position based on the contour lines of the received power created by suppressing the influence of fading.

Preferably, the data structure is such that the identification information of the primary user's wave source to which the shared frequency has already been assigned is the shared frequency, the position information indicating the center position of the contour line, the power value of the contour line, and the radius of the contour line. It has a structure further associated with.

By further including the identification information of the wave source of the primary user, the data structure accurately estimates the power value of the radio wave emitted from the primary user, and wireless communication is performed so as not to interfere with the primary user. It can be carried out.

It is possible to suppress fading and create contour lines of received power.

It is a schematic diagram which shows the wireless communication system by embodiment of this invention. It is a schematic diagram of the power estimation device shown in FIG. 1. It is a figure for demonstrating the method of making the contour line of the received power. It is a figure for demonstrating the extraction method of k monitor information. It is a figure for demonstrating the method 2 of making the contour line CTR of received power. It is a figure for demonstrating another extraction method of k monitor information. It is a figure which shows the relationship between the extraction method of k monitor information, and the process of making a contour line of received power. It is a figure for demonstrating another method of making a contour line of received power. It is a figure for demonstrating the method of estimating the received power in the region below the reception sensitivity of the radio wave in a terminal apparatus. It is a figure which shows the relationship between the received power and the distance from a wave source. It is a figure which shows the calculation result of the center of gravity point (x _G , y _G ) using the formula (1). It is a figure for demonstrating the problem at the time of calculating the center of gravity point (x _G , y _G ) using the equation (1). It is another figure for demonstrating the problem in calculating the center of gravity point (x _G , y _G ) using the equation (1). It is a figure for demonstrating the calculation method of the center of gravity point (x _G , y _G ) when the wave source position is biased to one side with respect to the distribution area of a terminal apparatus. It is a figure for demonstrating the method of determining which of the outer division point and the inner division point is used. It is a figure for demonstrating operation of the estimation means of the power estimation apparatus shown in FIG. It is a flowchart for demonstrating operation of the power estimation apparatus shown in FIG. It is a flowchart for demonstrating the detailed operation of step S1 of FIG. It is a flowchart for demonstrating the detailed operation of step S5 of FIG. It is a flowchart for demonstrating the detailed operation of step S55 shown in FIG. It is a flowchart for demonstrating another detailed operation of step S55 shown in FIG. It is a schematic diagram which shows the structure of another power estimation apparatus by embodiment of this invention. It is a conceptual diagram which shows the fluctuation of the received power with time. It is a figure which shows the relationship between the type of an error, and the required reliability rate. It is a figure which shows the relationship between the size of a sample, and the margin of error. It is a figure which shows the sample in the case of determining whether or not the received power is correct data. 22 is a flowchart for explaining the detailed operation of step S1 of FIG. 17 when the operation of the power estimation device shown in FIG. 22 is executed according to the flowchart shown in FIG. It is a figure for demonstrating the method of making the contour line of the received power which has an elliptical shape. It is a figure for demonstrating the method of making the contour line of the received power which has a polygonal shape. It is a schematic diagram of the data structure by embodiment of this invention. It is a schematic diagram of another data structure according to the embodiment of this invention.

Embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals and the description thereof will not be repeated.

FIG. 1 is a schematic diagram showing a wireless communication system according to an embodiment of the present invention. With reference to FIG. 1, the wireless communication system 10 according to the embodiment of the present invention includes a power estimation device 1, a plurality of terminal devices 2, and a base station 3.

The power estimation device 1 is connected to the base station 3 by a wired cable 4. The power estimation device 1 receives a plurality of monitor information in the plurality of terminal devices 2 from the base station 3 via the wired cable 4, and records the received plurality of monitor information. Here, each monitor information is from the position information indicating the position of the terminal device 2, the received power of the radio wave transmitted from the wave source S in the terminal device 2, the time information indicating the time when the received power is detected, and the wave source S. Contains frequency information indicating the frequency of transmitted radio waves.

Further, the power estimation device 1 also receives a plurality of monitor information transmitted from the base station not shown in FIG. 1 to the base station 3 from the base station 3 via the wired cable 4, and the received plurality of monitor information. To record.

That is, the power estimation device 1 receives and records the monitor information of the terminal device 2 existing in the area of the municipality or the area of the prefecture (target area REG for estimating the power) from the base station 3.

Then, the power estimation device 1 creates contour lines of received power based on the recorded plurality of monitor information by a method described later, and receives radio waves in the target area REG based on the created contour lines of received power. Estimate the power.

In this way, the power estimation device 1 estimates the received power of radio waves in a very wide target area REG.

The plurality of terminal devices 2 and the base station 3 are arranged in the wireless communication space. The plurality of terminal devices 2 are arranged around the wave source S.

Each of the plurality of terminal devices 2 is a plurality of frequencies included in any of a frequency band of 3 GHz or less, a frequency band of 3 GHz to 6 GHz, a frequency band of 6 GHz to 30 GHz, and a frequency band higher than 30 GHz. Uses the shared frequency _fcom shared by the terminal device 2 for wireless communication to perform wireless communication with another terminal device 2.

Each of the plurality of terminal devices 2 comprises a mobile terminal or a stationary terminal. Then, each of the plurality of terminal devices 2 detects its own position by, for example, GPS (Global Positioning System).

Further, each of the plurality of terminal devices 2 receives a radio wave having a shared frequency _fcom from the wave source S, and detects the received power RSSI _i (i = 1, 2, 3, ...) When the radio wave is received. do.

Further, each of the plurality of terminal devices 2 has a built-in timer, and detects the time when the received power RSSI _i is detected.

Then, each of the plurality of terminal devices 2 has position information ( _xi , _{y i} ) indicating its own position, received power RSSI _i , and time information ti indicating the time when the received power RSSI _i is detected. , Monitor information MNT_i = [ti :( x _i , y _i ), RSSI _i , f _{com_i} ] including the shared frequency f _com , and the generated monitor information MNT_i ₌ [ti: (x _i , y ₎ . _i ), RSSI _i , _{fcom_i} ] is transmitted to the base station 3 by wireless communication.

In this case, the terminal device 2 may directly transmit the monitor information MNT to the base station 3, or may transmit the monitor information MNT to the base station 3 by multi-hop.

Each of the plurality of terminal devices 2 has location information ( _xi , y _i ), received power RSSI _i , time information ti, and shared frequency _{fcom_i} , except when wirelessly communicating with another terminal device 2 _. Is detected and monitor information MNT_i = [ti :( x _i , y _i ), RSSI _i , _{frequency_i} ] is generated, and the generated monitor information MNT_i = [ti: (x _i , _{y i )} , RSSI _i , _{frequency_i} ] is transmitted to the base station 3 periodically (for example, at 1-minute intervals).

The base station 3 receives the monitor information MNT from the plurality of terminal devices 2, and transmits the received plurality of monitor information MNTs to the power estimation device 1 via the wired cable 4.

Further, the base station 3 transmits a plurality of monitor information MNTs received from a base station (not shown) to the power estimation device 1 via the wired cable 4.

The wave source S includes, for example, a radar, a radio relay transmission device (FPU: Field Pickup Unit) for television broadcasting, a relay station for relaying radio waves to remote islands, a terminal device, and the like.

FIG. 2 is a schematic view of the power estimation device 1 shown in FIG. With reference to FIG. 2, the power estimation device 1 includes a receiving means 11, a recording means 12, an extracting means 13, a creating means 14, and an estimating means 15.

The receiving means 11 receives a plurality of monitor information MNTs from the base station 3, and records the received plurality of monitor information MNTs in the recording means 12.

The recording means 12 records a plurality of monitor information MNTs received from the receiving means 11. More specifically, the recording means 12 sets a plurality of monitor information MNTs [t ₁ : (x ₁ , y ₁ ), RSSI ₁ , f _{com_1} ], [t ₂ : (x ₂ , y ₂ ), RSSI ₂ ). , F _{com_1} ], [t ₃ : (x ₃ , y ₃ ), RSSI ₃ , f _{com_1} ], ..., [t _T : (x _M , y _M ), RSSI _M , f _{com_1} ]; [t ₁ ] : (X ₁ , y ₁ ), RSSI ₁ , f _{com_} 2], [t ₂ : (x ₂ , y ₂ ), RSSI ₂ , f _{com_} 2], [t ₃ : (x ₃ , y ₃ ), RSSI ₃ , f _{com_2} ], ..., [t _T : (x _M , y _M ), RSSI _M , f _{com _2} ]; ...; [t ₁ : (x ₁ , y ₁ ), RSSI ₁ , f _{com_N} ], [T ₂ : (x ₂ , y ₂ ), RSSI ₂ , f _{com_N} ], [t ₃ : (x ₃ , y ₃ ), RSSI ₃ , f _{com_N} ], ..., [t _T : (x _M ,) y _M ), RSSI _M , _{fcom_N} ]. Here, T indicates the number of times of detection of the time information _ti , M indicates the number of terminal devices 2, and N indicates the number of shared frequencies f _com . Then, T is an integer of 2 or more, M is an integer larger than k described later, and N is an integer of 1 or more.

Further, the recording means 12 has the same position information ( _xi , _{y i} ) for the terminal device 2 which is a mobile terminal but is stopped or the terminal device 2 which is a stationary terminal, and the time information ti, The monitor information MNT is recorded so that the received power RSSI _i and the frequency information f _{com_j} (j is an integer satisfying 1 ≦ j ≦ N) are different.

Further, when the detection interval of the time information t _i is longer than the detection interval of the position information ( _xi , y _i ), the received power RSSI _i , and the frequency information _{fcom_j} , the recording means 12 sets a plurality of monitor information MNTs [t. ₁ : (x ₁ , y ₁ ), RSSI ₁ , f _{com_1} ], [t ₁ : (x ₂ , y ₂ ), RSSI ₂ , f _{com_1} ], [t ₁ : (x ₃ , y ₃ ), RSSI ₃ , F _{com_1} ], ..., [t ₁ : (x _M , y _M ), RSSI _M , f _{com_1} ]; [t ₂ : (x ₁ , y ₁ ), RSSI ₁ , f _{com_1} ], [t ₂ ] : (X ₂ , y ₂ ), RSSI ₂ , f _{com_2} ], [t ₂ : (x ₃ , y ₃ ), RSSI ₃ , f _{com_2} ], ..., [t ₂ : (x _M , y _M ) , RSSI _M , f _{com_2} ]; ...; [t _T : (x ₁ , y ₁ ), RSSI ₁ , f _{com_N} ], [t _T : (x ₂ , y ₂ ), RSSI ₂ , f _{com_N} ], Record as [t _T : (x ₃ , y ₃ ), RSSI ₃ , f _{com_N} ], ..., [t _T : (x _M , y _M ), RSSI _M , f _{com_N} ]. That is, the recording means 12 records a plurality of monitor information _{MNTs so that the position information (xi, y i) and the received power RSSI i change in the} same time information ti.

The extraction means 13 creates a distribution state of a plurality of monitor information MNTs based on the plurality of monitor information MNTs recorded in the recording means 12 by a method described later, and creates a distribution state of the created plurality of monitor information MNTs. Based on this, the processing range for performing the processing to create the contour lines of the received power is determined, and the k monitoring information MNT ₁ of the k (k is an integer of 2 or more) terminal devices 2 included in the determined processing range. ~ MNT _k is extracted. Then, the extraction means 13 outputs the extracted k monitor information MNT ₁ to MNT _k to the creation means 14. The extraction means 13 extracts k monitor information MNTs ₁ to MNT _k from a plurality of monitor information MNTs by the method described later until the received power RSSI _i of the power value P or more of the contour line CTR of the received power to be created disappears. Then, the process of outputting the extracted k monitor information MNT ₁ to MNT _k to the creating means 14 is repeated.

The creating means 14 receives k monitor information from the extraction means 13, calculates the center of gravity point RSSI_G of the received power by the method described later based on the received k monitor information, and determines the calculated received power. A contour line CTR of received power is created using the center of gravity point RSSI_G. Then, the creating means 14 outputs the created contour line CTR of the received power to the estimating means 15.

The estimation means 15 receives the contour line CTR of the received power from the creating means 14, and estimates the received power of the radio wave in the target region REG based on the contour line CTR of the received power by the method described later. Then, the estimation means 15 has communication conditions (shared frequency f _com , location, transmission power, etc.) when the plurality of terminal devices 2 perform wireless communication using the shared frequency f _com based on the estimated received power of the radio wave. ) Is determined.

FIG. 3 is a diagram for explaining a method of creating a contour line CTR of received power. In FIG. 3, the white square indicates the measurement point where the power value is P (= the power value of the contour line CTR of the received power) or more, the black square indicates the measurement point where the power value is less than P, and the white circle indicates the measurement point. , The center of gravity point RSSI_G of the received power is shown. Further, the measurement points s1 to s3 indicate measurement points where the received power becomes less than the power value P due to the influence of fading. Each of the white square and the black square consists of position information ( _xi , y _i ) and received power RSSI _i .

With reference to FIG. 3A, the extraction means 13 of the power estimation device 1 distributes a plurality of monitor information MNTs based on the plurality of monitor information MNTs recorded in the recording means 12 ((A) of FIG. The distribution state) shown in a) is acquired.

Then, the extraction means 13 determines the power value P of the contour line CTR of the received power to be created. The extraction means 13 determines, for example, −60 dBm, −70 dBm, −80 dBm, or the like as the power value P.

The extraction means 13 holds in advance the relationship between the power value P and the radius r of the processing range. For example, the extraction means 13 holds in advance a relationship such as a radius r of the processing range r = 500 m with respect to the power value P of −60 dBm and a radius of 1500 m of the processing range with respect to the power value P of −70 dBm.

When the extraction means 13 determines the power value P of the contour line CTR of the received power to be created, the extraction means 13 determines the maximum value RSSI_MAX of the received power having the power value P or more among the plurality of received power RSSI _i included in the plurality of monitor information MNTs. To extract. Here, the reason why the maximum value RSSI_MAX of the received power is extracted is that the terminal device 2 having the maximum value RSSI_MAX of the received power is considered to be the closest to the wave source S.

Then, when the extraction means 13 creates a contour line CTR of the received power having a power value P of -60 dBm, when the maximum value RSSI_MAX of the received power is extracted, the extraction means 13 is centered on the measurement point having the maximum value RSSI_MAX of the extracted received power. The range with a radius r = 500 m is determined as the processing range REG_PRS.

Then, the extraction means 13 extracts the k monitor information MNT ₁ to MNT _k in the processing range REG_PRS, and outputs the extracted k monitor information MNT ₁ to MNT _k to the creating means 14.

With reference to FIG. 3B, the creating means 14 receives k monitor information MNTs ₁ to MNT _k from the extraction means 13, and k included in the received k monitor information MNTs ₁ to MNT _k . Based on the received power RSSI ₁ to RSSi _k , the center of gravity point RSSI_G (x _G , y _G ) of the received power is calculated by the following equation.

In the formula (1), wi represents the weight of the _i -th terminal device 2 and is composed of the received power RSSI _i in the i-th terminal device 2.

That is, the creating means 14 calculates the average of the positions of the k terminal devices 2 weighted by the k received power RSSI _i (i = 1 to k), thereby calculating the center of gravity point RSSI_G (x _G ,) of the received power. y _G ) is calculated.

Then, the creating means 14 has the received power RSSI _i of the power value P or more among the k received power RSSI _i (i = 1 to k), and the center of gravity point RSSI_G (x _G , y) of the received power. The distance between the terminal device 2-1 located at the farthest position from _G ) and the center of gravity point RSSI_G (x _G , y _G ) of the received power is obtained as the maximum radius R. Then, the creating means 14 creates a contour line CTR of the received power having a circular shape centered on the center of gravity point RSSI_G (x _G , y _G ) of the received power and having the maximum radius R as the radius.

As described above, the creating means 14 excludes the received power (black square) having a power value less than P, and determines the maximum radius R based only on the received power (white square) having a power value P or more. Among the measurement points indicated by the black squares, the measurement points s1 to s3 are the measurement points whose received power is less than the power value P due to the influence of fading.

Therefore, according to the method of creating the contour line CTR of the received power by the creating means 14, it is possible to suppress the influence of fading and create the contour line CTR of the received power.

In the above, it was explained that k is an integer of 2 or more, but this is due to the following reason. When k = 2, one of the two received power RSSI _i is the maximum value RSSI_MAX of the received power, and the other is the received power equal to or more than the power value P or less than the power value P. It is the received power whose received power is unknown. Then, using these two received power RSSI _i , the center of gravity point RSSI_G (x _G , y _G ) of the received power is calculated by the equation (1).

As a result, the center of gravity point RSSI_G (x _G , y _G ) of the received power deviates from the measurement point having the maximum value RSSI_MAX of the received power.

Then, since the maximum value RSSI_MAX of the received power is equal to or greater than the power value P, the distance between the center of gravity point RSSI_G (x _G , y _G ) of the received power and the measurement point having the maximum value RSSI_MAX of the received power is set as the maximum radius R. It can be obtained and a contour line CTR of received power can be created.

Therefore, k may be 2 or more.

If there is at least one received power RSSI _i having a power value P or more, the position of the terminal device 2 having at least one received power RSSI _i is deviated from the center of gravity point RSSI_G of the received power, so that the maximum radius R Can be determined, and a contour line CTR of received power can be created. Therefore, the number of received powers having a power value P or more required to create a contour line CTR of received power is one or more.

FIG. 4 is a diagram for explaining a method of extracting k monitor information MNT ₁ to MNT _k . In FIG. 4, black circles indicate each measurement point (monitor information MNT) and do not discriminate whether the power value is P or more or less than the power value P.

With reference to FIG. 4A, the extraction means 13 determines the processing range REG_PRS_1 by the method described above, and extracts and creates k monitor information MNTs ₁ to MNT _k existing in the processing range REG_PRS_1. Output to means 14. Then, the creating means 14 creates contour lines CTR 1 of the received power by the above-mentioned method based on the k monitor information MNT ₁ to MNT _k received from the extracting means 13.

With reference to FIG. 4B, the extraction means 13 then excludes the k monitor information MNTs ₁ to MNT _k existing in the processing range REG_PRS_1 and determines the processing range REG_PRS_2 by the method described above. Then, k new monitor information MNTs ₁ to MNT _k existing in the processing range REG_PRS_2 are extracted and output to the creating means 14. Then, the creating means 14 creates contour lines CTR 2 of the received power by the above-mentioned method based on the new k monitor information MNT ₁ to MNT _k received from the extracting means 13.

Then, the extraction means 13 processes by the above-mentioned method while excluding the k monitor information MNT ₁ to MNT _k already extracted until the received power equal to or higher than the power value P of the contour line CTR of the received power to be created is exhausted. The range REG_PRS is determined, and the extraction of k new monitor information MNTs ₁ to MNT _k existing in the determined processing range REG_PRS is repeatedly executed.

Then, each time the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k , the creating means 14 extracts the contour line CTR of the received power based on the k pieces of monitor information MNT ₁ to MNT _k by the above-mentioned method. To create.

In this case, the creating means 14 creates a contour line CTR of received power by using one of the following two methods.

(1) Creation method 1
The creating means 14 does not use the k monitor information MNT ₁ to MNT _k already used for creating the contour line CTR of the received power, but is based on the k monitor information MNT ₁ to MNT _k received from the extracting means 13. Create a contour CTR of received power.

(2) Creation method 2
The creating means 14 is included in both the _k monitor information MNT _{1 to MNT k already used for creating the contour line CTR of the received power and the new k monitor information MNT 1 to} MNT _k received from the extracting means 13. A contour line CTR of the received power is created based on the monitor information and the new monitor information MNT ₁ to MNT _k .

FIG. 5 is a diagram for explaining a method 2 for creating a contour line CTR of received power. With reference to FIG. 5, the monitor information MNT ₁ includes the maximum value RSSI_MAX 1 of the received power, and the monitor information MNT ₂ includes the maximum value RSSI_MAX 2 of the received power when the monitor information MNT ₁ is excluded. Further, the monitor information MNT ₃ and MNT ₄ include received power having a power value P or more. Further, the white circle indicates the center of gravity point RSSI_G of the received power.

The extraction means 13 determines the processing range REG_PRS_3, and extracts k pieces of monitor information MNT_REG_PRS_3 existing in the processing range REG_PRS_3.

Then, the creating means 14 creates the contour line CTR1 of the received power by the above-mentioned method based on the k monitor information MNT_REG_PRS_3 received from the extracting means 13.

After that, the extraction means 13 determines the processing range REG_PRS_4 except for the k monitor information MNT_REG_PRS_3 existing in the processing range REG_PRS_3, and extracts the k monitor information MNT_REG_PRS_4 existing in the processing range REG_PRS_4.

In this case, the monitor information MNT ₃ and MNT ₄ are included in both the k monitor information MNT_REG_PRS_3 and the k monitor information MNT_REG_PRS_4.

Then, the creating means 14 calculates the center point RSSI_G1 of the received power based on the k monitor information MNT_REG_PRS_4 and the monitor information MNT ₃ and MNT ₄ , and sets the distance between the center point RSSI_G1 of the received power and the monitor information MNT ₄ as the radius. Create a contour line CTR2 of received power having a circular shape.

When the contour line CTR of the received power is created without including the monitor information MNT ₃ and MNT ₄ , the center point RSSI_G of the received power becomes the center point RSSI_G2 of the received power, and the monitor information MNT ₂ including the maximum value RSSI_MAX2 of the received power. The deviation from the position of is large, and the contour line CTR of the received power has a circular shape having a radius smaller than that of the contour line CTR2 of the received power. As a result, it becomes difficult to accurately create contour lines CTR of received power.

However, by creating the contour line CTR of the received power including the monitor information MNT ₃ and MNT ₄ , the center of gravity RSSI_G1 of the received power exists in the vicinity of the position of the monitor information MNT ₂ including the maximum value RSSI_MAX2 of the received power. , Contour lines CTR2 of received power with a larger radius are created. As a result, the contour line CTR of the received power can be created with high accuracy.

FIG. 6 is a diagram for explaining another extraction method of k monitor information MNT ₁ to MNT _k . With reference to FIG. 6, the maximum value RSSI_MAX6 of the received power is smaller than the maximum value RSSI_MAX5 of the received power.

The extraction means 13 determines the processing range REG_PRS_5 by the method described above, and extracts k pieces of monitor information MNT ₁ to MNT _k existing in the processing range RG_PRS_5 (see (a) in FIG. 6).

After that, the extraction means 13 determines the processing range REG_PRS_6 by excluding only the monitor information MNT including the maximum value RSSI_MAX 5 of the received power from the k monitor information MNTs ₁ to MNT _k in the already extracted processing range REG_PRS_5. , K monitor information MNT ₁ to MNT _k existing in the processing range REG_PRS_6 are extracted (see (b) in FIG. 6).

As described above, the extraction means 13 is the maximum value of the received power among the k monitor information MNT ₁ to MNT _k already extracted until the received power equal to or higher than the power value P of the contour line CTR of the received power to be created disappears. While excluding only the monitor information including RSSI_MAX, k new monitor information MNT ₁ to MNT _k are repeatedly extracted.

Then, each time the creating means 14 receives k monitor information MNT ₁ to MNT _k from the extraction means 13, the receiving power is generated by the above-mentioned method based on the received k monitor information MNT ₁ to MNT _k . Create a contour CTR.

As described above, the extraction means 13 removes at least the monitor information MNTs including the maximum value RSSI_MAX of the received power from the k monitor information MNTs ₁ to MNT _k that have already been extracted, and the extraction means 13 has k monitor information MNTs ₁ to MNT. Extracting _k is repeated until there is no received power equal to or higher than the power value P of the contour line CTR of the received power to be created.

FIG. 7 is a diagram showing the relationship between the extraction method of k monitor information MNT ₁ to MNT _k and the process of creating the contour line CTR of the received power.

With reference to FIG. 7, the extraction method of k monitor information MNT ₁ to MNT _k has already extracted k monitor information until the received power equal to or higher than the power value P of the contour line CTR of the received power to be created disappears. Extraction method 1 that extracts new k monitor information MNT ₁ to MNT _k while excluding MNT ₁ to MNT _k , and until the received power of the contour line CTR power value P or more of the received power to be created is exhausted. Extraction method 2 for extracting new k monitor information MNT ₁ to MNT _k while excluding only the monitor information MNT including the maximum value RSSI_MAX of the received power from the extracted k monitor information MNT ₁ to MNT _k . including.

Further, in the process of creating the contour line CTR of the received power, the center of gravity RSSI_G of the received power is calculated based on the extracted k monitor information MNT ₁ to MNT _k , and the received power having the power value P or more is obtained. , The distance between the terminal device located at the farthest position from the center point RSSI_G of the received power and the center point RSSI_G of the received power is obtained as the maximum distance, and the center point RSSI_G of the received power is the center and the maximum distance is the radius. The contour line creation process 1 for creating the contour line CTR of the received power having a circular shape, and the already extracted k monitor information MNT ₁ to MNT _k and the newly extracted k monitor information MNT ₁ to MNT _k . The center of gravity RSSI_G of the received power is calculated based on the monitor information included in both and the new k monitor information MNT ₁ to MNT _k , and the received power having the power value P or more and the received power The distance between the terminal device located at the farthest position from the center of gravity RSSI_G and the center of gravity RSSI_G of the received power is obtained as the maximum distance, and it has a circular shape centered on the center of gravity RSSI_G of the received power and the maximum distance as the radius. It includes the contour line creation process 2 for creating the contour line CTR of the received power.

Then, when the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 1, the creation means 14 creates a contour line CTR of the received power according to the contour line creation process 1, or follows the contour line creation process 2. Create a contour CTR of received power.

Further, when the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 2, the creation means 14 creates a contour line CTR of the received power according to the contour line creation process 1.

Here, when the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 1 and the creation means 14 creates the contour line CTR of the received power according to the contour line creation process 1, the calculation amount is the largest. When the number is reduced, the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 1, and the creation means 14 creates the contour line CTR of the received power according to the contour line creation process 2, the calculation amount is 2. When the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 2, and the creation means 14 creates the contour line CTR of the received power according to the contour line creation process 1, the calculation amount is the second smallest. Is the most.

When the extraction means 13 extracts k monitor information MNTs ₁ to MNT _k according to the extraction method 1, and the creation means 14 creates the contour line CTR of the received power according to the contour line creation process 1, the k monitors already extracted. Extract k new monitor information MNT ₁ to MNT _k while excluding information MNT _{1 to MNT k, and plot the contour line CTR of received power based on the extracted new k monitor information MNT 1 to MNT k} . Since it is created, the number of received power RSSI _i equal to or greater than the power value P of the contour line CTR of the received power to be created is I (I is an integer satisfying 1 ≦ I ≦ M, and M is the total number of the plurality of terminal devices 2. If there are (an integer that satisfies M ≧ k), the number of times the contour line CTR of the received power is created is INT [I / k] (I / k converted into an integer). Since it is possible that all of the plurality of terminal devices 2 have the received power RSSI _i of the power value P or more of the contour line CTR of the received power, I is M or less.

When the extraction means 13 extracts k monitor information MNTs ₁ to MNT _k according to the extraction method 1, and the creation means 14 creates the contour line CTR of the received power according to the contour line creation process 2, the k pieces already extracted. Received based on the monitor information included in both the monitor information MNT ₁ to MNT _k and the newly extracted k monitor information MNT ₁ to MNT _k , and the new k monitor information MNT ₁ to MNT _k . Since the contour line CTR of the power is created, the number of times the contour line CTR of the received power is created is INT [I / k], but the monitor information (received power RSSI _i and position) when calculating the center of gravity point RSSI_G of the received power. The number of information (x _i , y _i )) and the number of monitor information (received power RSSI _i and position information (x _i , y _i )) when calculating the maximum distance are larger than in the case of contour line creation process 1. The amount of calculation is larger than that in the case of the contour line creation process 1.

When the extraction means 13 extracts k monitor information MNT ₁ to MNT _k according to the extraction method 2, and the creation means 14 creates the contour CTR of the received power according to the contour creation process 1, the k monitors already extracted. Of the information MNT ₁ to MNT _k , k new monitor information MNT ₁ to MNT _k are extracted while excluding only the monitor information MNT including the maximum value RSSI_MAX of the received power, and the extracted new k monitors. Since the contour line CTR of the received power is created based on the information MNT ₁ to MNT _k , the number of times to create the contour line CTR of the received power is I times. When k = 2 and I = 1, the number of times I of creating the contour line CTR of the received power when the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k by the extraction method 2 is extracted. The number of times of creating contour line CTRs of received power when the means 13 extracts k pieces of monitor information MNT ₁ to MNT _k by the extraction method 1 is equal to INT [I / k] (number of times of creating contour line CTRs = 1 time). On the other hand, when I ≧ 2, when the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k by the extraction method 2, the number of times I of creating the contour line CTR of the received power I is determined by the extraction method 13. The number of times the contour line CTR of the received power is created when k pieces of monitor information MNT ₁ to MNT _k are extracted is larger than INT [I / k]. In the embodiment of the present invention, the target area REG for which the creating means 14 creates the contour line CTR of the received power is the area of the municipality or the area of the prefecture as described above, so that the situation where I = 1 is usually used. , It is thought that it is unlikely to occur. As a result, when the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k by the extraction method 2, the number of times I of creating the contour line CTR of the received power is usually the largest. Therefore, when the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 2, and the creation means 14 creates the contour line CTR of the received power according to the contour line creation process 1, the amount of calculation is the largest.

Then, the method in which the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 1 and the creation means 14 creates the contour line CTR of the received power according to the contour line creation process 1 is defined as the first method. The second method is a method in which the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 1 and the creation means 14 creates contour line CTRs of received power according to the contour line creation process 2. When the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k according to the extraction method 2 and the creation means 14 creates the contour line CTR of the received power according to the contour line creation process 1 as the third method. , The contour line CTR of the received power is created by using the first method when the calculation amount is set to the minimum, and is created by using the second method when the calculation amount is set to be the second smallest. , When the calculation amount is allowed to be the maximum calculation amount, it is created by using the third method.

FIG. 8 is a diagram for explaining another method of creating a contour line CTR of received power. In FIG. 8, the white square indicates the measurement point where the power value is P or more, the black square indicates the measurement point where the power value is less than P, and the white circle indicates the center of gravity point RSSI_G of the received power. Further, each of the white square and the black square consists of position information ( _xi , y _i ) and received power RSSI _i .

The creating means 14 creates contour lines CTR3 and CTR4 of received power based on k monitors MNT ₁ to MNT _k by the method described above (see (a) in FIG. 8).

Then, when the contour lines CTR3 and CTR4 of the two received powers intersect each other, the creating means 14 synthesizes the contour lines CTR3 and CTR4 of the received power to create the contour lines CTR_SYN of the received power (see (b) in FIG. 8). ).

The contour line CTR_SYN of the received power has the shape of a snowman.

As described above, when there are a plurality of wave sources S for transmitting signals at the shared frequency f _com , the creating means 14 sets the center of gravity points (x _G , y _G ) of the received power as a virtual wave source group (set of a plurality of wave sources S). Create a contour line CTR of the received power by regarding it as a wave source.

In the conventional technique, contour lines of received power are created for each wave source, so that the amount of calculation increases as the number of wave sources increases.

On the other hand, in the embodiment of the present invention, since the contour line CTR of the received power is created for each wave source group, the processing amount of the power estimation device 1 does not increase so much even if there are a plurality of wave sources. The amount of processing can be reduced compared to.

FIG. 9 is a diagram for explaining a method of estimating received power in a region below the reception sensitivity of radio waves in the terminal device 2.

Since the terminal device 2 cannot acquire the received power below the reception sensitivity, the contour line CTR of the received power in the region below the reception sensitivity is created based on the contour line CTR of the received power already created and the propagation model of the radio wave.

FIG. 10 is a diagram showing the relationship between the received power and the distance from the wave source. In FIG. 10, the vertical axis represents the received power, and the horizontal axis represents the distance from the wave source S.

In the free space propagation model of radio waves, the received power RSSI _i decreases in inverse proportion to the distance from the wave source S as shown in FIG.

In the free space propagation model of radio waves, when the distance from the wave source S is 1000 m or more, the received power RSSI _i decreases linearly with the increase of the distance. The distance when the received power RSSI _i is reduced by 10 dBm is 3.16 km. That is, in the free space propagation model of radio waves, the distance when the received power RSSI _i decreases by 10 dBm is 3.16 km / 10 dBm.

Therefore, in the region below the reception sensitivity of the radio wave, the creating means 14 is separated from the already created contour line CTR_SYN (contour line of the power value P) by 3.16 km in a direction far from the wave source, and is a contour line of the received power. A contour line CTR_LS of received power having a similar shape to CTR_SYNC is created as a contour line CTR having a power value of P-10 (see FIG. 9).

In this case, the power value of the received power in the contour line CTR_LS is not limited to P-10, and may be any power value that is lower than the power value P by a desired power value ΔP. Therefore, the creating means 14 obtains the distance when the power value P is lower than the power value P in the free space propagation model of the radio wave, and is separated from the wave source by the obtained distance, and the contour line CTR_SYN of the received power is obtained. The contour line CTR_LS of the received power having a similar shape to is created as the contour line CTR having the power value of P−ΔP.

The radio wave propagation model is not limited to the free space propagation model, and may be any propagation model.

Therefore, the creating means 14 generally has a power reduction distance (3.) in which the received power becomes a desired power value lower than the power value on the contour line CTR of the received power already created in the region below the reception sensitivity of the radio wave. 16km, etc.) is obtained based on the propagation model of the radio wave, and the contour line CTR that is separated from the already created contour line CTR of the received power by the power reduction distance and has a shape similar to the contour line CTR of the already created received power is the reception sensitivity of the radio wave. Created as a contour CTR of received power in the following areas.

As described above, since the creating means 14 creates the contour line CTR of the received power even in the region below the reception sensitivity of the radio wave, the contour line CTR of the received power can be created in a wide range of the received power RSSI _i .

A detailed calculation method of the center of gravity point (x _G , y _G ) of the received power will be described.

As shown in FIG. 10, the received power RSSI _i is attenuated in inverse proportion to the distance from the wave source S. As a result, the received power RSSI _i becomes larger as it approaches the wave source S, so that the effect of weighting by the received power RSSI _i is greater in the vicinity of the wave source S. Therefore, the center of gravity point (x _G , y _G ) of the received power calculated using the equation (1) approaches the vicinity of the wave source.

FIG. 11 is a diagram showing a calculation result of the center of gravity point (x _G , y _G ) using the equation (1).

The wave source S is arranged at the position (300, 300) in the xy coordinates. The number of terminal devices 2 is 50. The white circle in FIG. 11 represents the terminal device 2. The radius of the target area is 1000 m.

The position of the center of gravity point (x _G , y _G ) calculated using the equation (1) was (295,306).

Therefore, it was found that the center of gravity points (x _G , y _G ) calculated using the equation (1) are located in the vicinity of the wave source S.

FIG. 12 is a diagram for explaining a problem in calculating the center of gravity point (x _G , y _G ) using the equation (1).

In FIG. 12, circles represent the positions of the center of gravity points (x _G , y _G ), and squares represent the source positions.

With reference to FIG. 12A, when the distribution of the terminal device 2 is uniform, the position of the center of gravity (x _G , y _G ) is accurately located in the vicinity of the wave source position.

On the other hand, when the distribution of the terminal device 2 is biased, the position of the center of gravity (x _G , y _G ) is significantly different from the wave source position. Since the center of gravity point (x _G , y _G ) calculated using the equation (1) is located in the center of the region where the terminal device 2 is distributed, the distribution region of the plurality of terminal devices 2 is the wave source position. When it is biased to one side with respect to the other, the position of the center of gravity (x _G , y _G ) is not located near the source position (see (b) in FIG. 12).

FIG. 13 is another diagram for explaining a problem in calculating the center of gravity point (x _G , y _G ) using the equation (1).

FIG. 13 shows the position of the terminal device 2, the wave source position, and the position of the center of gravity (x _G , y _G ) in the x-axis direction, and shows the change of the received power RSSI _i in the x-axis direction with respect to the distance.

FIG. 13A shows a case where the wave source position exists between the two terminal devices 2, and FIG. 13B shows a case where the wave source position exists on one side of the two terminal devices 2.

In FIGS. 13A and 13B, the received power RSSI _i is attenuated in inverse proportion to the distance from the wave source position.

When the wave source position exists between the two terminal devices 2, the position of the center of gravity (x _G , y _G ) exists in the vicinity of the wave source position.

On the other hand, when the wave source position exists on one side of the two terminal devices 2, the position of the center of gravity (x _G , y _G ) exists between the two terminal devices 2 and is greatly deviated from the wave source position.

As described above, even in one dimension, when the wave source position is biased to one side of the terminal device 2, the position of the center of gravity (x _G , y _G ) is greatly deviated from the wave source position.

FIG. 14 is a diagram for explaining a method of calculating the center of gravity point (x _G , y _G ) when the wave source position is biased to one side with respect to the distribution region of the terminal device 2.

When the positions of the terminal device 2-1 and the terminal device 2-2 are close to each other, the position of the terminal device 2-1 (x ₁ , y ₁ ) and the position of the terminal device 2-2 (x ₂ , y ₂ ). The point (x _E , y _E ) that externally divides and into w ₁ : w ₂ is obtained as the center of gravity point (x _G , y _G ) of the received power.

In this case, x _E and y _E are expressed by the following equations.

With reference to the distribution of received power RSSI _i by distance (FIG. 10), the wave source S is biased to the right side of the terminal devices 2-1 and 2-2 on the paper of FIG. 14, and therefore the terminal device 2-2. The received power RSSI _2-2 of is larger than the received power RSSI _2-1 of the terminal device 2-1.

Therefore, of the received power RSSI _2-1 and RSSI _2-2 of the terminal devices 2-1 and 2, the position of the terminal device 2-1 is located on the terminal device 2-2 side having the large received power RSSI _2-2 ( The external division point (x _E , y _E ) obtained by dividing x ₁ , y ₁ ) and the position (x ₂ , y ₂ ) of the terminal device 2-2 into w ₁ : w ₂ is the center of gravity point (x) of the received power. It is calculated as _G , _yG ).

When x _E and y _E become negative values, it is not calculated by a simple sum, so any two terminal devices 2 are extracted from the plurality of terminal devices 2, and the two positions of the extracted two terminal devices 2 are outside. The process of dividing and obtaining the outer dividing points is executed for all the two terminal devices 2, and the average value of the obtained plurality of outer dividing points is obtained as the center of gravity points (x _G , y _G ) of the received power.

Assuming that the total number of terminal devices 2 is M, the average values x _{E_ave} and y _{E_ave} of the outer division points are determined by the following equations.

In the equation (3), w _i is composed of the received power RSSI _i of the i-th terminal device 2, and w _j is composed of the received power RSSI _j of the j-th terminal device 2.

FIG. 15 is a diagram for explaining a method of determining which of the outer division point and the inner division point is used.

With reference to FIG. 15, when the diameter of the processing range REG_PRS is D and the distance between the two terminal devices 2 is d, when d is equal to or larger than the radius (= D / 2) of the processing range REG_PRS, the center of gravity point. (X _G , y _G ) exists between the two terminal devices 2. This is because, as described above, the processing range REG_PRS has a circular shape centered on the terminal device 2 having the maximum value RSSI_MAX of the received power.

On the other hand, when d is smaller than the radius (= D / 2), the center of gravity point (x _G , y _G ) exists at a position biased to one side of the two terminal devices 2.

Therefore, when the distance d between the two terminal devices 2 is equal to or greater than the radius (= D / 2) of the processing range REG_PRS, the internal division point obtained by internally dividing the positions of the two terminal devices 2 is the center of gravity point (x _G , y). When the distance d between the two terminal devices 2 is smaller than the radius (= D / 2) of the processing range _{REG_PRS} , the external division point obtained by externally dividing the positions of the two terminal devices 2 is the center of gravity point (x). It is calculated as _G , _yG ).

That is, the center of gravity point (x _G , y _G ) is obtained by the following equation.

The x _Est and y _Est of the equation (4) indicate the center of gravity point (x _G , y _G ). Further, xth shown in the equation (4) is the radius of the processing range _{REG_PRS} in the x-axis direction, and yth is the radius of the processing range _{REG_PRS} in the y-axis direction.

FIG. 16 is a diagram for explaining the operation of the estimation means 15 of the power estimation device 1 shown in FIG. FIG. 16 shows a contour line CTR of received power having a power value of −80 dBm and a contour line CTR of received power having a power value of −90 dBm.

With reference to FIG. 16, the estimation means 15 of the power estimation device 1 receives the contour line CTR of the received power created by the creation means 14. Further, the estimation means 15 divides the target area REG into a mesh-like area, for example. Then, the estimation means 15 displays the contour line CTR of the received power received from the creating means 14 in the target area REG, and estimates the received power in each mesh based on the displayed contour line CTR.

The received power estimated by the estimation means 15 is used to determine communication conditions (shared frequency _fcom , location, transmission power, etc.) when performing wireless communication using the shared frequency _fcom .

FIG. 17 is a flowchart for explaining the operation of the power estimation device 1 shown in FIG. With reference to FIG. 17, when the operation of the power estimation device 1 is started, the extraction means 13 exists in the processing range REG_PRS by the method described above based on the plurality of monitor information MNTs recorded in the recording means 12. The k monitor information MNT ₁ to MNT _k are extracted (step S1). Then, the extraction means 13 outputs the extracted k monitor information MNTs ₁ to MNT _k to the creation means 14 (step S2).

After that, the extraction means 13 excludes the k monitor information MNT ₁ to MNT _k already extracted, or the monitor having the maximum received power RSSI_MAX among the k monitor information MNT ₁ to MNT _k already extracted. The information MNT is excluded (step S3).

Then, the extraction means 13 is the maximum value of the received power among the plurality of monitor information excluding the k monitor information MNT ₁ to MNT _k already extracted, or the k monitor information MNT ₁ to MNT _k already extracted. Based on a plurality of monitor information excluding the monitor information MNT having RSSI_MAX, it is determined whether or not there is a received power RSSI _i having a power value P or more of the contour line CTR of the received power to be created (step S4).

When it is determined in step S4 that there is a received power RSSI _i equal to or higher than the power value P of the contour line CTR of the received power to be created, the series of operations returns to step S1 and the received power to be created in step S4. Steps S1 to S4 are repeatedly executed until it is determined that there is no received power RSSI _i equal to or higher than the power value P of the contour line CTR.

Then, in step S4, when it is determined that the received power RSSI _i of the power value P or more of the contour line CTR of the received power to be created does not exist, the creating means 14 extracts k pieces of monitor information MNT ₁ to MNT _k . Each time it is received from the means 13, a contour line CTR of received power is created by the above-mentioned method based on k monitor information MNT ₁ to MNT _k (step S5).

Then, the creating means 14 outputs the created contour line CTR of the received power to the estimating means 15.

The estimation means 15 receives the contour line CTR of the received power from the creating means 14, and estimates the received power at each location based on the contour line CTR of the received power (step S6). As a result, the operation of the power estimation device 1 is completed.

In step S1, when the extraction means 13 has a plurality of received power maximum values RSSI_MAX having the same power value in the processing range REG_PRS, the extraction means 13 receives power of one of the plurality of received power maximum values RSSI_MAX. Select the maximum value RSSI_MAX of, exclude the other maximum value RSSI_MAX of the received power, and select k monitor information MNTs in the processing range REG_PRS.

In the embodiment of the present invention, since the extraction means 13 extracts k monitor information MNTs according to the extraction method 1 or the extraction method 2, k monitor information MNTs are excluded while at least excluding the maximum value RSSI_MAX of the received power. Is repeatedly extracted.

Therefore, in step S1, the extraction means 13 has a case where the maximum value RSSI_MAX of a plurality of received powers having the same power value (maximum value RSSI_MAX of the received power equal to or higher than the power value P of the contour line CTR) exists in the processing range REG_PRS. , Select the maximum received power RSSI_MAX of one of the maximum received power RSSI_MAX, exclude the other maximum received power RSSI_MAX, and select k monitor information MNTs in the processing range REG_PRS. By doing so, the creating means 14 creates contour lines CTR of received power based on k monitor information MNTs including each of a plurality of maximum values RSSI_MAX of received power.

As a result, even when a plurality of maximum received power RSSI_MAX having the same power value exists in the processing range REG_PRS, the contour line CTR of the received power can be accurately created.

FIG. 18 is a flowchart for explaining the detailed operation of step S1 of FIG.

With reference to FIG. 18, after the "start" of FIG. 17, or in step S4 of FIG. 17, when it is determined that there is a received power RSSI _i equal to or greater than the power value P of the contour line CTR of the received power to be created. The extraction means 13 obtains the maximum value RSSI_MAX of the received power based on the plurality of monitor information MNTs (step S11).

Then, the extraction means 13 determines whether or not the maximum value RSSI_MAX of the received power is equal to or greater than the power value P of the contour line CTR of the received power to be created (step S12). If step S11 is executed after it is determined in step 4 of FIG. 17 that there is a received power RSSI _i equal to or higher than the power value P of the contour line CTR of the received power to be created, the maximum value RSSI_MAX of the received power is set to. Normally, the power value P or more of the contour line CTR of the received power to be created is equal to or higher than the power value P. In this case, step S12 is executed to more accurately create the contour line CTR of the received power.

When it is determined in step S12 that the maximum value RSSI_MAX of the received power is not equal to or greater than the power value P of the contour line CTR to be created, the series of operations shifts to the "end" of FIG.

On the other hand, when it is determined in step S12 that the maximum value RSSI_MAX of the received power is equal to or greater than the power value P of the contour line CTR to be created, the extraction means 13 has a radius r centered on the maximum value RSSI_MAX of the received power. The processing range REG_PRS is determined (step S13).

Then, the extraction means 13 extracts k pieces of monitor information MNT ₁ to MNT _k existing in the processing range REG_PRS (step S14).

After that, the series of operations proceeds to step S2 in FIG.

When the flowchart shown in FIG. 18 is executed after it is determined that the received power RSSI _i of the power value P or more of the contour line CTR of the received power to be created in step S4 of FIG. 17 exists, the extraction means 13 is executed. K pieces of monitor information MNT ₁ to MNT _k are extracted according to the extraction method 1 or the extraction method 2 shown in FIG. 7.

FIG. 19 is a flowchart for explaining the detailed operation of step S5 of FIG.

With reference to FIG. 19, when it is determined in step S4 of FIG. 17 that there is no received power RSSI _i equal to or greater than the power value P of the contour line CTR of the received power to be created, the creating means 14 receives the received power to be created. It is determined whether or not the power value P of the contour line CTR of the power is equal to or higher than the reception sensitivity of the terminal device 2 (step S51).

When it is determined in step S51 that the power value P of the contour line CTR of the received power to be created is not equal to or higher than the reception sensitivity of the terminal device 2, the creating means 14 determines whether or not the contour line CTR of the received power already created exists. Further determination (step S52).

When it is determined in step S52 that there is no contour line CTR of the received power already created, the creating means 14 selects a new P (step S53). After that, the series of operations proceeds to step S51.

On the other hand, when it is determined in step S52 that there is a contour line CTR of the received power already created, the creating means 14 uses the contour line CTR of the received power already created and the radio wave propagation model by the above-mentioned method. A contour line CTR of received power is created in a region below the reception sensitivity of radio waves (step S54).

When it is determined in step S51 that the power value P of the contour line CTR of the received power to be created is equal to or higher than the reception sensitivity of the terminal device 2, the creating means 14 is based on k pieces of monitor information MNT ₁ to MNT _k . The center of gravity point RSSI_G of the received power is calculated (step S55).

Then, the creating means 14 obtains the distance between the terminal device having the received power equal to or higher than the power value P and existing at the position farthest from the center of gravity point RSSI_G of the received power and the center of gravity point RSSI_G of the received power as the maximum distance. (Step S56).

Then, the creating means 14 creates a contour line CTR of the received power having a circular shape centered on the center of gravity point RSSI_G of the received power and having the maximum distance as the radius (step S57).

Then, after step S54 or step S57, the series of operations shifts to step S6 in FIG.

FIG. 20 is a flowchart for explaining the detailed operation of step S55 shown in FIG.

With reference to FIG. 20, when it is determined in step S51 of FIG. 19 that the power value P of the contour line CTR of the received power to be created is equal to or higher than the reception sensitivity of the terminal device 2, the creating means 14 has a plurality of monitors. The variance Var of the distribution of the information MNT is calculated (step S551), and it is determined whether or not the calculated variance Var is equal to or greater than the threshold value Var_th (step S552).

When it is determined in step S552 that the distributed Var is equal to or greater than the threshold value Var_th, the creating means 14 uses the equation (1) based on the k monitor information MNTs ₁ to MNT _k to receive the received power RSSI. The center of gravity points (x _G , y _G ) of the received power weighted by _i are calculated (step S553).

On the other hand, when it is determined in step S552 that the distributed Var is not equal to or greater than the threshold value Var_th, the creating means 14 extracts any two monitor information MNTs from the plurality of monitor information MNTs and two monitor information MNTs. The distance between them is calculated (step S554).

Then, the creating means 14 determines whether or not the distance between the two monitor information MNTs is equal to or greater than the threshold value (= radius of the processing range REG_PRS) (step S555).

When it is determined in step S555 that the distance between the two monitor information MNTs is not equal to or greater than the threshold value (= radius of the processing range REG_PRS), the creating means 14 calculates the outer division points of the two monitor information MNTs (= Step S556).

On the other hand, when it is determined in step S555 that the distance between the two monitor information MNTs is equal to or greater than the threshold value (= radius of the processing range REG_PRS), the creating means 14 sets the internal division points of the two monitor information MNTs. Calculate (step S557).

Then, after step S556 or step S557, the creating means 14 determines whether or not the evaluation of all the monitor information MNTs has been completed (step S558).

When it is determined in step S558 that the evaluation of all monitor information MNTs has not been completed, the series of operations returns to step S554, and in step S558, it is determined that the evaluation of all monitor information MNTs has been completed. Up to, the above-mentioned steps S554 to S558 are repeatedly executed.

Then, when it is determined in step S558 that the evaluation of all the monitor information MNTs has been completed, the creating means 14 calculates the average value of the internal division points or the external division points using the equation (4) (step S559). ), And the calculated average value is obtained as the center of gravity point RSSI_G of the received power (step S560).

Then, after step S553 or step S560, the series of operations shifts to step S56 in FIG.

As described above, in the embodiment of the present invention, the center of gravity points of k received powers weighted by the received power RSSI _i based on the plurality of monitor information MNTs (position information and received power) of the plurality of terminal devices. Since the average value of the internal division point or the external division point of the RSSI_G or the two monitor information MNTs is obtained as the center of gravity point RSSI_G of the received power, the center of gravity point RSSI_G of the received power can be obtained by using the four rules. Therefore, the center of gravity point RSSI_G of the received power can be easily obtained by suppressing the amount of calculation.

Further, in the flowchart shown in FIG. 20, since the inner division point and the outer division point are used properly, the center of gravity point RSSI_G of the received power can be accurately obtained even when the position of the monitor information MNT is biased with respect to the wave source S. ..

In addition, in step S559 of FIG. 20, it was explained that the inner division point or the outer division point is simply averaged to obtain the average value, but in the embodiment of the present invention, the present invention is not limited to this, and the inner division point or the outer division point is obtained. The average value of the inner or outer division points may be obtained by weighting with the average power of the two received power RSSI _i of the two monitor information used for obtaining the division points.

That is, the average value of the inner division points may be obtained by the following equation (5), and the average value of the outer division points may be obtained by the equation (6).

FIG. 21 is a flowchart for explaining another detailed operation of step S55 shown in FIG.

The flowchart shown in FIG. 21 is the same as the flowchart shown in FIG. 19 except that steps S554 to S557 of the flowchart shown in FIG. 19 are replaced with steps S561 to S568.

With reference to FIG. 21, when it is determined in step S51 of FIG. 19 that the power value P of the contour line CTR of the received power to be created is equal to or higher than the reception sensitivity of the terminal device 2, the above-mentioned steps S551 to S553 are performed. It is executed sequentially.

Then, when it is determined in step S552 that the distributed Var is smaller than the threshold value Var_th, the creating means 14 extracts arbitrary two monitor information MNTs from the k monitor information MNTs ₁ to MNT _k , and x. The distance Lx between the two monitor information MNTs in the axial direction and the distance Ly between the two monitor information MNTs in the y-axis direction are calculated (step S561).

Then, the creating means 14 determines whether or not the distance Lx in the x-axis direction is equal to or greater than the threshold value L_th_x (step S562). The threshold value L_th_x is set to the radius of the processing range REG_PRS in the x-axis direction.

When it is determined in step S562 that the distance Lx is not equal to or greater than the threshold value L_th_x, the creating means 14 further determines whether or not the distance Ly in the y-axis direction is equal to or greater than the threshold value L_th_y (step S563). The threshold value L_th_y is set to the radius of the processing range REG_PRS in the y-axis direction.

On the other hand, when it is determined in step S562 that the distance Lx is equal to or greater than the threshold value L_th_x, the creating means 14 further determines whether or not the distance Ly in the y-axis direction is equal to or greater than the threshold value L_th_y (step). S564).

When it is determined in step S563 that the distance Ly is not equal to or greater than the threshold value L_th_y, the creating means 14 calculates an external division point between the two monitor information MNTs in both the x-axis direction and the y-axis direction (step). S565).

On the other hand, when it is determined in step S563 that the distance Ly is equal to or greater than the threshold value L_th_y, the creating means 14 calculates an external division point between the two monitor information MNTs in the x-axis direction and in the y-axis direction. The internal division point between the two monitor information MNTs is calculated (step S566).

Further, when it is determined in step S564 that the distance Ly is not equal to or greater than the threshold value L_th_y, the creating means 14 calculates an internal division point between the two monitor information MNTs in the x-axis direction, and in the y-axis direction, The outer division point between the two monitor information MNTs is calculated (step S567).

On the other hand, when it is determined in step S564 that the distance Ly is equal to or greater than the threshold value L_th_y, the creating means 14 calculates an internal division point between the two monitor information MNTs in both the x-axis direction and the y-axis direction. (Step S568).

Then, after any one of steps S565 to S568, the series of operations proceeds to step S558, and steps S561 to S568 described above are described until it is determined in step S558 that the evaluation of all monitor information MNTs has been completed. , S558 are repeatedly executed.

Then, when it is determined in step S558 that the evaluation of all the monitor information MNTs has been completed, the above-mentioned steps S559 and S560 are sequentially executed. In this case, in step S559, the creating means 14 calculates the average value of the inner division point or the outer division point in the x-axis direction and the y-axis direction, respectively.

As described above, according to the flowchart shown in FIG. 21, since either the inner division point or the outer division point is used separately for the x-axis direction and the y-axis direction (see steps S562 to S568), the calculation is performed in step S559. The average value is closer to the source position.

Therefore, the center of gravity point RSSI_G of the received power can be obtained more accurately.

Further, also in the flowchart shown in FIG. 21, since the inner division point and the outer division point are used properly, even if the position of the monitor information MNT is biased with respect to the wave source S, the center of gravity point RSSI_G of the received power can be obtained accurately. ..

FIG. 22 is a schematic diagram showing the configuration of another power estimation device according to the embodiment of the present invention. The power estimation device according to the embodiment of the present invention may be the power estimation device 1A shown in FIG.

With reference to FIG. 22, the power estimation device 1A replaces the extraction means 13 of the power estimation device 1 shown in FIG. 2 with the extraction means 13A, and is the same as the power estimation device 1 in other respects.

The extraction means 13A reads a plurality of monitor information MNTs from the recording means 12, and receives power RSSI _i by time based on a plurality of received power RSSI _i and a plurality of time information ti included in the read plurality of monitor information _MNTs . Record the fluctuations in. Then, the extraction means 13A estimates, based on the fluctuation of the received power RSSI _i with time, which error factor such as noise and fading causes the received power RSSI _i to fluctuate.

After that, the extraction means 13A detects the received power RSSI _i _CFD satisfying the required reliability rate from the plurality of received power RSSI _i by the method described later, and sets the processing range REG_PRS based on the detected received power RSSI _i _CFD. decide.

FIG. 23 is a conceptual diagram showing changes in the received power RSSI _i over time. With reference to FIG. 23, in the propagation environment affected by fading, the received power RSSI _i fluctuates as shown by the curve k1 with time.

Further, when the propagation environment is a propagation environment affected by noise, the received power RSSI _i fluctuates differently from the curve k1 depending on the time.

The extraction means 13A holds a variation characteristic in which the variation of the received power RSSI _i with time is associated with error factors such as noise and fading. Then, the extraction means 13A determines which fluctuation characteristic the fluctuation of the received power RSSI _i read from the recording means 12 with time matches or approximates, and detects an error factor corresponding to the matching or approximation fluctuation characteristic. Thereby, the error factor that the received power RSSI _i fluctuates with time is estimated.

The distribution of errors such as noise and fading can be either a normal distribution, a rice distribution, or a Rayleigh distribution. The normal distribution is the distribution of the error when the error factor is noise, and the rice distribution and the Rayleigh distribution are the distribution of the error when the error factor is fading. And the Rayleigh distribution is the distribution of the error when the scattering is intense.

Therefore, in the embodiment of the present invention, the propagation environment of the radio wave is estimated, and the distribution of the error factor is determined to be one of the normal distribution, the rice distribution, and the Rayleigh distribution according to the estimated propagation environment of the radio wave. Then, the received power RSSI _{i_CFD} that satisfies the reliability rate corresponding to the determined distribution of error factors is detected.

The extraction means 13A detects fluctuations in the received power RSSI _i over time based on the monitor information from the stationary terminal or the monitor information MNT from the mobile terminal having the slowest moving speed, and the time of the detected received power RSSI _i . Estimate the propagation environment such as the propagation environment with fading or the propagation environment with noise based on the fluctuation caused by.

Then, the extraction means 13A determines the distribution of the error factors to be one of a normal distribution, a rice distribution, and a Rayleigh distribution according to the estimated propagation environment.

FIG. 24 is a diagram showing the relationship between the type of error and the required reliability rate. With reference to FIG. 24, when the type of error is a normal distribution, the required confidence rate is, for example, 0.95, and the distribution point α is a normal distribution point having a confidence rate of 0.95. When the type of error is rice distribution, the required reliability is, for example, 0.90, and the distribution point β is a rice distribution point having a reliability of 0.90. When the type of error is Rayleigh distribution, the required reliability is, for example, 0.80, and the distribution point γ is a Rayleigh distribution point having a reliability of 0.80.

The extraction means 13A holds a correspondence table TBL showing a correspondence relationship between the type of error shown in FIG. 24 and the required reliability rate. Then, when the extraction means 13A determines the distribution of the error factors, the extraction means 13A refers to the correspondence table TBL and detects the reliability rate corresponding to the determined distribution of the error factors.

After that, the extraction means 13A reads out a plurality of monitor information MNTs, and detects the received power RSSI _{i_CFD} that satisfies the required reliability rate based on the read-out plurality of monitor information MNTs.

More specifically, the extraction means 13A detects the received power RSSI _{i_CFD} by the following method. The extraction means 13A extracts a plurality of received power RSSI _i with different times from the received power received from one terminal device 2. For example, the extraction means 13A extracts 10 received power RSSI _i (i = 1 to 10) having different times. Then, the extraction means 13A calculates Z by the following equation using 10 received power RSSI _i (i = 1 to 10) having different times.

In equation (7), n is the size of the number of samples, e is the margin of error, and Z is the distribution point having the reliability α. Q is the ratio of the received power used to create the contour line CTR of the received power in the population. For example, when creating a contour line CTR of received power using 10 received power RSSI _i (i = 1 to 10) out of 100 received power RSSI _i (i = 1 to 100), Q = 0. It is 1. M is a population.

FIG. 25 is a diagram showing the relationship between the sample size n and the margin of error range e. FIG. 25 shows the relationship between the sample size n and the margin of error e when the average received power is −100 dBm and the reliability α is 0.95.

With reference to FIG. 25, the sample size n consists of, for example, 10, 20, 50, 100. The margin of error range e is set to, for example, 10% when the sample size n is 10, and is set to, for example, 7% when the sample size n is 20, and the sample size n is set. If it is 50, it is set to, for example, 5%, and if the sample size n is 100, it is set to, for example, 3%. In this way, the margin of error range e is set so as to decrease as the sample size n increases.

When the sample size n is 10, there is a true value in the range of −110 to −90 dBm with a probability of 95% (reliability α = 0.95). Further, when the sample size n is 100, there is a true value in the range of −103 to −97 dBm with a probability of 95% (reliability α = 0.95).

Since the permissible error range e is set so as to decrease as the sample size n increases, the larger the sample size n, the smaller the permissible error range e and the accuracy improves.

Further, the distribution point of the reliability rate α and the tolerance range e are set according to the required accuracy. If the sample size n does not increase, the restrictions on the reliability α or the margin of error e are alleviated. If the sample size n does not increase, if the reliability α is set high or the tolerance range e is set narrow, the received power that satisfies the reliability α or the margin of error e disappears, and a contour line CTR of the received power is created. Because it will not be possible.

M is the total number of received power RSSI _i , n is 10 received powers at different times (the number of received powers of a part of the total number M of received powers), and e is shown in FIG. 25. Since it is known and Q is also known, the extraction means 13A can calculate Z by the equation (7).

Then, the extraction means 13A determines whether or not the calculated Z satisfies the reliability rate. More specifically, when Z satisfies the reliability rate, the extraction means 13A determines the received power RSSI _i as correct data, and when Z does not satisfy the reliability rate, the received power RSSI _i is regarded as incorrect data. judge.

Here, whether or not Z satisfies the reliability rate is determined by whether or not Z falls within the range where the deviation is ± 0.05 in the normal distribution when the error distribution follows a normal distribution. Then, when Z falls in the range where the deviation is ± 0.05 in the normal distribution, it is determined that Z satisfies the reliability rate, and when Z does not fall in the range where the deviation is ± 0.05 in the normal distribution, Z. Is determined not to satisfy the reliability rate.

When the extraction means 13A determines that the received power RSSI _i is incorrect data, the extraction means 13A determines whether or not the received power RSSI _i is correct data for another received power RSSI _i by the method described above.

Even when the error distribution is a rice distribution or a Rayleigh distribution, the extraction means 13A determines whether or not the received power RSSI _i is correct data in the same manner as when the error distribution is a normal distribution.

Further, the extraction means 13A extracts a plurality of received power RSSI _i having the same time information from the plurality of received power RSSI _i received from different terminal devices 2, and each of the extracted plurality of received power RSSI _i . The above-mentioned method may be used to determine whether or not the received power RSSI _i is correct.

FIG. 26 is a diagram showing a sample when determining whether or not the received power RSSI _i is correct data.

With reference to (a) of FIG. 26, n (n is an integer satisfying 2 ≦ n <i) received powers RSSI ₁ to RSSI _n receive different time information at positions (x ₁ , y ₁ ). It is electric power.

With reference to (b) of FIG. 26, _n received powers _RSSI'1 to _RSSI'n are received powers having different position information in the time information t1.

When determining whether or not the received power is correct data using n received powers RSSI ₁ to RSSI _n , the extraction means 13A has a normal distribution of n received powers RSSI ₁ to RSSI _n , rice. Determine whether it corresponds to the distribution or the Rayleigh distribution. Then, when it is determined that the extraction means 13A corresponds to the normal distribution, the extraction means 13A detects the reliability rate of 0.95 corresponding to the normal distribution by referring to the correspondence table TBL.

After that, the extraction means 13A calculates Z using the formula (7), and determines whether or not the calculated Z satisfies the reliability rate by the method described above.

Even when the distribution of n received powers RSSI ₁ to RSSI _n is a rice distribution or a Rayleigh distribution, the extraction means 13A similarly determines whether or not the calculated Z satisfies the reliability rate by the method described above. ..

Then, when it is determined that Z satisfies the reliability rate, that is, when it is determined that n received powers RSSI ₁ to RSSI _n are correct data, the extraction means 13A receives at the position (x ₁ , y ₁ ). Detects power (received power at a position (x ₁ , y ₁ ) having the same time information as received power at a position different from the position (x ₁ , y ₁ )) as one data for creating a contour line CTR of received power. do.

As described above, since the creating means 14 creates contour lines CTR of received power using a plurality of received power RSSI _i detected at different positions, n pieces detected at the same position (x ₁ , y ₁ ). This is because the received powers RSSI ₁ to RSSI _n of the above cannot be used as the received power for creating the contour line CTR of the received power.

When determining whether or not the received power is correct data using n received powers RSSI ₁ to RSSI _n , the extraction means 13A has a distribution of n received powers RSSIs ₁ to RSSI _n . Determine whether it corresponds to the normal distribution, the rice distribution, or the Rayleigh distribution. Then, when it is determined that the extraction means 13A corresponds to the normal distribution, the extraction means 13A detects the reliability rate of 0.95 corresponding to the normal distribution by referring to the correspondence table TBL.

After that, the extraction means 13A calculates Z using the formula (7), and determines whether or not the calculated Z satisfies the reliability rate by the method described above.

Even when the distribution of _n received powers _RSSI'1 to RSSI'n is a rice distribution or a Rayleigh distribution, the extraction means 13A similarly determines whether or not the calculated Z satisfies the reliability rate by the method described above. judge.

Then, when the extraction means 13A determines that Z satisfies the reliability rate, that is, when it is determined that n received power RSSIs ₁ to RSSI _n are correct data, n received power RSSIs ₁ ~ _RSSI'n is detected as data for creating a contour line CTR of received power.

Since _n received powers _RSSI'1 to RSSI'n are received powers detected at different positions, they can be used as data for creating contour line CTRs of received powers in the creating means 14 if the reliability rate is satisfied. Because.

Therefore, the extraction means 13A detects _n received powers _RSSI'1 to RSSI'n as a correct set of data.

On the other hand, when the extraction means 13A determines that the n received powers RSSI ₁ to RSSI _n are not correct data, another n having at least one of the n received power RSSIs ₁ to RSSI _n is different. The received powers are extracted, and whether or not the extracted n received powers are correct data is determined by the method described above.

Detecting the received power satisfying the required reliability rate by the method described above corresponds to detecting the received power satisfying the required reliability rate according to the radio wave propagation environment. The extraction means 13A estimates the propagation environment of the radio wave, determines the distribution of error factors according to the estimated propagation environment, and determines the reliability rate (required reliability rate) corresponding to the determined distribution of error factors. This is because the received power RSSI _{i_CFD} that is satisfied is detected.

The operation of the power estimation device 1A is executed according to the flowchart shown in FIG.

27 is a flowchart for explaining the detailed operation of step S1 of FIG. 17 when the operation of the power estimation device 1A shown in FIG. 22 is executed according to the flowchart shown in FIG.

With reference to FIG. 27, it is determined that when the operation of the power estimation device 1A is started, or the received power RSSI _i of the power value P or more of the contour line CTR of the received power to be created in step S4 of FIG. 17 exists. At that time, the extraction means 13A estimates the distribution of errors by the method described above (step S21).

Then, the extraction means 13A acquires k monitor information MNTs ₁ to MNT _k from the recording means 12 (step S22).

Then, the extraction means 13A calculates Z based on the k monitor information MNTs ₁ to MNT _k by the above-mentioned method, and determines whether or not the calculated Z satisfies the reliability rate (step S23). ..

When it is determined in step S23 that Z does not satisfy the reliability rate, the series of operations returns to step S22, and steps S22 and S23 are repeatedly executed until Z is determined to satisfy the reliability rate in step S23. Will be done. In this case, when the extraction means 13A returns from step S23 to step S22 and acquires k monitor information MNT _{1 to MNT k, at least one of the k monitor information MNT 1 to MNT k already acquired} . Acquires k monitor information MNTs ₁ to MNT _k with different monitor information MNTs.

Then, when it is determined in step S23 that Z satisfies the reliability rate, the extraction means 13A determines as a processing range a range including k pieces of monitor information MNT ₁ to MNT _k when Z satisfies the reliability rate. (Step S24).

After that, the extraction means 13A extracts k pieces of monitor information MNT ₁ to MNT _k when Z satisfies the reliability rate.

Then, the series of operations proceeds to step S2 in FIG.

When the extraction means 13A repeatedly extracts k pieces of monitor information MNT ₁ to MNT _k according to the flowchart shown in FIG. 27, until the received power RSSI _i of the power value P or more of the contour line CTR of the received power to be created disappears. , K pieces of monitor information MNT ₁ to MNT _k are repeatedly extracted using the above-mentioned extraction method 1 or extraction method 2.

Further, since the k monitor information MNTs ₁ to MNT _k extracted in step S25 include the maximum value RSSI_MAX of the received power, the creating means 14 has k monitor information MNTs ₁ to MNT received from the extraction means 13A. Based on _k , the contour line CTR of the received power can be created by the method described above.

In this way, the power estimation device 1A extracts k pieces of monitor information RSSI i_CFD ( _i = 1 to k) that satisfy the required reliability rate from the received power RSSI _i received from the terminal device 2, and extracts them. Since the contour line CTR of the received power is created based on the k monitor information RSSI i_CFD ( _i = 1 to k), the contour line CTR of the received power is accurate even in an environment where error factors such as noise and fading exist. Can be created well.

The estimation of the received power in the power estimation devices 1 and 1A may be performed by software.

In this case, each of the power estimation devices 1 and 1A includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory).

The ROM is a program Prog_A consisting of the flowcharts shown in FIG. 17 (including the flowcharts shown in FIGS. 18 to 21) or the program Prog_B consisting of the flowcharts shown in FIG. 17 (including the flowcharts shown in FIGS. 19 to 21 and 27). To store.

Then, the CPU reads one of the programs Prog_A and Prog_B from the ROM, executes any of the read programs Prog_A and Prog_B, and estimates the received power.

In this case, the RAM is used for storing the monitor information MNT received from the terminal device 2 and is used for various operations.

Further, any of the programs Prog_A and Prog_B may be recorded on a recording medium such as a CD or DVD and distributed. In this case, the CPU reads out one of the programs Prog_A and Prog_B from the mounted recording medium, executes the program, and estimates the received power. Therefore, the recording medium such as a CD or DVD on which any of the programs Prog_A and Prog_B is recorded is a recording medium that can be read by a computer (CPU).

In the above, it has been described that the contour line CTR of the received power has a circular shape centered on the center point RSSI_G of the received power and the radius is the maximum distance, but the present invention is limited to this. However, the contour line CTR of the received power may have an elliptical shape centered on the center point RSSI_G of the received power and having the maximum distance as the major axis.

FIG. 28 is a diagram for explaining a method of creating a contour line CTR of received power having an elliptical shape.

In FIG. 28, a white square indicates a measurement point having a received power of a power value P or more, a black square indicates a measurement point having a received power less than the power value P, and a white circle indicates a center of gravity point RSSI_G of the received power. show.

With reference to FIG. 28, the creating means 14 creates contour lines CTR5 of received power having a circular shape centered on the center of gravity point RSSI_G of the received power and having a radius of the maximum distance R by the method described above.

Then, the creating means 14 has an elliptical shape centered on the center point RSSI_G of the received power, the maximum distance R as the major axis, and the distance R'as the minor axis, based on the contour line CTR 5 of the received power. Create contour line CTR6 of. Here, the distance R'has a received power equal to or higher than the power value P, and the distance from the center point RSSI_G of the received power is the second longest after the maximum distance R. The measurement point 2-2 and the center point RSSI_G of the received power. Is the distance to.

Further, in the embodiment of the present invention, the contour line CTR of the received power may have a polygonal shape.

FIG. 29 is a diagram for explaining a method of creating a contour line CTR of received power having a polygonal shape.

In FIG. 29, a white square indicates a measurement point having a received power of a power value P or more, a black square indicates a measurement point having a received power less than the power value P, and a white circle indicates a center of gravity point RSSI_G of the received power. show.

With reference to FIG. 29, the creating means 14 creates contour lines CTR5 of received power having a circular shape centered on the center of gravity point RSSI_G of the received power and having a radius of the maximum distance R by the method described above.

Then, the creating means 14 forms a regular octagon 20 inscribed in the contour line CTR 5 of the received signal having a circular shape (see (a) in FIG. 29).

After that, the creating means 14 sets the measurement points 2-1 to 2-8 in which each vertex of the regular octagon has a received power of the power value P or more and exists at a position as far as possible from the center of gravity RSSI_G of the received power. The regular octagon 20 is deformed so as to be positioned, and a contour line CTR7 of received power having an octagonal shape is created (see (b) in FIG. 29).

The creating means 14 creates a contour line CTR of received power having a polygonal shape other than an octagon by the same creating method as that described in FIG. 29.

As described above, the creating means 14 creates not only the contour line CTR of the received power having a circular shape but also the contour line CTR of the received power having an elliptical shape or the contour line CTR of the received power having a polygonal shape.

Even when the creating means 14 creates a contour line CTR of received power having an elliptical shape or a polygonal shape, a plurality of contour line CTRs of received power having an elliptical shape or a polygonal shape are coupled to the wave source group. Create a contour line CTR of the received power having the shape of the ellipse.

Therefore, in step S57 of the flowchart shown in FIG. 19, the creating means 14 replaces the received power contour line CTR having a circular shape with the received power contour line CTR having an elliptical shape or the received power contour line having a polygonal shape. A CTR may be created, and in general, the creating means 14 is a circle centered on the center point RSSI_G of the received power and having the maximum distance R having the longest distance from the center point RSSI_G of the received power as the radius. Centered on the first contour line having a shape, the center point RSSI_G of the received power, and centered on the second contour line having an elliptical shape with the maximum distance R as the major axis, and the center point RSSI_G of the received power, and the maximum Any third contour line having a polygonal shape with the distance R as the distance from the center to one apex may be created.

Since the monitor information MNT includes the shared frequency f _{com_i} , the power estimation devices 1 and 1A create contour lines CTR of the received power when radio waves are transmitted using each shared frequency f _{com_i} by the above-mentioned method. The received power is estimated based on the created contour line CTR of the received power.

Further, in the power estimation devices 1 and 1A, for example, when the terminal device 2 performs wireless communication at 15:00, a plurality of monitor information transmitted from the plurality of terminal devices 2 between 14:00 and 15:00. Based on the MNT, a contour line CTR of the received power is created by the above-mentioned method (including a contour line CTR of the received power in the region below the reception sensitivity of the radio wave in the terminal device 2), and the contour line CTR of the received power created is also created. The received power at each location is estimated based on the above, and the communication conditions (shared frequency f _com , location, transmission power, etc.) when performing wireless communication using the shared frequency _{fcom_i} are determined based on the estimation result. ..

Then, each terminal device 2 performs wireless communication using the communication conditions determined by the power estimation devices 1 and 1A.

As a result, since the received power estimated by the power estimation devices 1 and 1A is the received power estimated by suppressing fading, the transmission power can transmit the signal to the transmission destination in the radio wave environment where fading is suppressed. Is decided. Therefore, the throughput can be increased and the signal can be transmitted to the destination.

FIG. 30 is a schematic diagram of a data structure according to an embodiment of the present invention. With reference to FIG. 30, the data structure D_STR1 has a terminal device ID, time information, position information of the terminal device 2, frequency band ID, and subcarrier No. , The wave source ID and the received power are associated with each other. Terminal device ID, time information, position information of terminal device 2, frequency band ID, subcarrier No. , The wave source ID and the received power constitute the monitor information MNT.

The terminal device ID is identification information of the terminal device 2. The time information indicates the time when the received power was detected. The time information is expressed in the format of year / month / day / hour / minute / second (YYYY / MM / DD / HH / MM / SS). The position information of the terminal device 2 includes latitude, longitude, and height. Latitude and longitude are detected by GPS and height is detected by an altimeter. The height indicates the height from the ground where the terminal device 2 is stationary or moving.

The frequency band ID is frequency band identification information shared by the plurality of terminal devices 2. Subcarrier No. Indicates the subcarrier number. The wave source ID is identification information of the wave source that emits the radio wave of the primary user. The received power is the received power of the radio wave received by each terminal device 2.

The terminal device ID is used by the extraction means 13 to determine whether or not the corresponding received power is detected by the same terminal device 2. The time information is used by the extraction means 13 to determine whether or not the corresponding received power is detected at the same time. The position information of the terminal device 2 is used by the extraction means 13 to determine whether or not the corresponding received power is detected at the same position, or whether or not the corresponding received power is detected within a predetermined area. .. Further, the position information is used by the creating means 14 to detect the terminal device located at the position farthest from the distance between the plurality of terminal devices 2, the distance between the terminal device 2 and the wave source, and the center of gravity of the received power. ..

The frequency band ID is used by the extraction means 13 to extract the received power in the same frequency band. Subcarrier No. Is used by the extraction means 13 to determine the subcarrier to which the radio wave having the corresponding received power is transmitted. The wave source ID is used by the extraction means 13 to extract the received power of the radio wave transmitted from the same wave source.

The received power is used by the creating means 14 to detect the maximum received power among the plurality of received powers. Further, the received power is used by the creating means 14 to detect the received power equal to or higher than the power value of the contour lines of the power to be created.

Among the plurality of received powers included in the plurality of monitor information MNTs, k monitor information including the maximum value of the received power is extracted from the plurality of monitor information by the extraction means 13.

For the k monitor information extracted by the extraction means 13, the creating means 24 obtains the center of gravity points (x _G , y _G ) of the received power, which is the average of the positions of the k terminal devices 2 weighted by the received power. Used for.

Of the k received powers included in the k monitor information extracted by the extraction means 13, the received power equal to or higher than the power value on the contour line of the received power to be created and the received power equal to or higher than the power value on the contour line of the received power. The position information associated with the above means that the creating means 14 has a terminal device located at the position farthest from the center point of the received power (x _G , y _G ) and the center point of the received power (x _G , y _G ). It is used to obtain the maximum distance (for example, the maximum radius R) which is the distance of.

The maximum distance determined by the creating means 14 is used by the creating means 14 to create one of a first contour line, a second contour line, and a third contour line.

The first contour line has a circular shape centered on the center of gravity of the received power and has a radius of the maximum distance, and the second contour line has a major axis centered on the center of gravity of the received power and the maximum distance. The third contour line has a polygonal shape centered on the center of gravity of the received power and the maximum distance is the distance from the center to one apex.

Preferably, among the k received powers included in the k monitor information extracted by the extraction means 13, the received power smaller than the power value in the contour line of the received power to be created and the power value in the contour line of the received power. The position information associated with the smaller received power is used by the estimation means 15 to estimate the received power of the radio wave at a desired place in the target area based on the contour line of the received power.

Preferably, the plurality of monitor information MNTs exclude at least the maximum value of the received power already extracted from the plurality of monitor information MNTs until the extraction means 13 has no more received power than the contour power value of the received power to be created. However, it is used to repeatedly extract k new monitor information MNT ₁ to MNT _k . Then, the new k monitor information MNTs ₁ to MNT _k extracted by the extraction means 13 are used by the creating means 14 to create contour lines of the received power based on the new k monitor information.

Preferably, the plurality of monitor information MNTs include k new monitor information MNTs ₁ to MNT _k , while the extraction means 13 removes the k monitor information MNTs ₁ to MNT _k already extracted from the plurality of monitor information MNTs. _{The first extraction method} for extracting Using the second extraction method, k new monitor information MNTs ₁ to MNT _k are repeatedly extracted from a plurality of monitor information MNTs until the received power equal to or higher than the contour line power value of the received power to be created is exhausted. Used for. Then, when the extraction means 13 extracts the new k monitor information MNT ₁ to MNT _k by the first extraction method, the new k monitor information MNT ₁ to MNT _k are created by the creating means 14. The first contour line creation process for creating contour lines of received power based on k monitor information MNT ₁ to MNT _k , and the center of gravity point (x) of received power based on the new k monitor information MNT ₁ to MNT _k . _G , y _G ) is obtained, and the monitor information MNT included in both the already extracted k monitor information MNT ₁ to MNT _k and the new k monitor information MNT ₁ to MNT _k , and the new k monitor information MNT. Monitor information of MNT ₁ to MNT _k and the second contour line creation process for creating contour lines of received power by finding the maximum distance based on the center of gravity points (x _G , y _G ) of received power. It is used to perform each time when k new monitor information MNT ₁ to MNT _k are extracted. When the extraction means 13 extracts k new monitor information MNT ₁ to MNT _k by the second extraction method, the new k monitor information MNT ₁ to MNT _k are created by the creating means 14 and k new pieces. Monitor information MNT ₁ to MNT _k are used to perform the first contour line creation process each time they are extracted.

Preferably, the first method is a method in which the extraction means 13 extracts k new monitor information MNTs ₁ to MNT _k by the first extraction method, and the creation means 14 performs the first contour line creation process. The second method is a method in which the extraction means 13 extracts k new monitor information MNTs ₁ to MNT _k by the first extraction method and the creation means 14 performs the second contour line creation process. When the means 13 extracts k new monitor information MNTs ₁ to MNT _k by the second extraction method and the creating means 14 performs the first contour line creating process as the third method, the extraction is performed. When the calculation amount of the new k monitor information MNT ₁ to MNT _k extracted by the means 13 is set to the minimum, the creating means 14 creates contour lines of the received power by using the first method. When used and set to be the second smallest amount of calculation, the creation means 14 is used to create contour lines of received power using the second method, and the amount of calculation is the maximum amount of calculation. If this is acceptable, the creating means 14 is used to create contour lines of received power using the third method.

Preferably, k pieces of monitor information MNT ₁ to MNT _k are used to be extracted by the extraction means 13 so that each received power satisfies the reliability rate required according to the radio wave environment.

Preferably, the received power having the contour line power value of the received power is a power desired by the creating means 14 to be higher than the power value on the contour line of the received power already created in the region below the reception sensitivity of the radio wave in the terminal device 2. The power reduction distance that results in a lower received power is obtained based on the radio wave propagation model, and an contour line that is separated from the already created received power contour line by the power reduction distance and has a shape similar to the already created received power contour line is obtained. It is used to create contour lines of received power in the region below the reception sensitivity of radio waves.

The data structure D_STR1 is used by the power estimation device 1 (or any of the programs Prog_A and Prog_B) to create contour lines of received power by the method described above. The data structure D_STR1 has a terminal device ID, time information, position information of the terminal device 2, a frequency band ID, and a subcarrier No. It is not necessary to include all of the wave source ID and the received power, but at least the position information, the frequency band ID and the received power of the terminal device 2 are included, and the position information, the frequency band ID and the received power of the terminal device 2 are associated with each other. It suffices to have a structure. If the data structure D_STR1 includes at least the position information, frequency band ID, and received power of the terminal device 2, the power estimation device 1 (or one of the programs Prog_A and Prog_B) creates contour lines of the received power by the method described above. Because it can be done. In this case, the position information, frequency band ID, and received power of the terminal device 2 constitute monitor information.

FIG. 31 is a schematic diagram of another data structure according to an embodiment of the present invention. The data structure according to the embodiment of the present invention may be the data structure D_STR2 shown in FIG.

With reference to FIG. 31, the data structure D_STR2 has an estimated primary user ID, time information, frequency band ID, and subcarrier No. , Wave source ID, center position of contour line, power value of contour line and radius of contour line are associated with each other. Frequency band ID, subcarrier No. And the wave source ID are as described in FIG.

The time information indicates the time when the contour line of the received power was created. The time information is expressed in the format of year / month / day / hour / minute / second (YYYY / MM / DD / HH / MM / SS). The estimated primary user ID is the estimated primary user identification information. The center position of the contour line includes latitude, longitude, and height. Latitude and longitude are detected by GPS and height is detected by an altimeter. And the height indicates the height from the ground at the center position of the contour line. The power value of the contour line is the power value on the created contour line. The radius of the contour line is the radius of the circle when the created contour line has a circular shape, and is the distance from the center of gravity point (x _G , y _G ) of the received power to the contour line.

The time information is used to identify the time when the creating means 14 created the contour lines of the received power. The frequency band ID is used to indicate that the creating means 14 has created contour lines of received power based on the received power in the same frequency band. Subcarrier No. Is used to determine the subcarrier to which the radio wave having the received power, which is the basis when the creating means 14 creates the contour lines of the received power, is transmitted. The wave source ID is used to identify the source of the contour lines of the received power created by the creating means 14.

The frequency band ID is used by the extraction means 13 to identify a shared frequency shared by k (k is an integer of 2 or more) terminal devices. The position information indicating the center position of the contour line is determined by the received power based on the k received power included in the k monitor information received from the k terminal devices and the k position information of the k terminal devices. It consists of the center of gravity points (x _G , y _G ) of the received power, which is the result of calculating the average of the positions of the weighted k terminal devices by the creating means 14. The radius of the contour line has the received power equal to or higher than the power value in the contour line of the received power to be created among the k received powers, and is located at the position farthest from the center of gravity point (x _G , y _G ) of the received power. It consists of the maximum distance that is the result of calculating the distance between the existing terminal device and the center of gravity point (x _G , y _G ) of the received power by the creating means 14. The power value of the contour line is the power value of the radio wave having the frequency band ID (shared frequency), and is the power value detected by the creating means 14.

Preferably, the primary user's wave source identification information to which the shared frequency has already been assigned further corresponds to the shared frequency, the position information indicating the center position of the contour line, the power value of the contour line, and the radius of the contour line by the creating means 14. It has an attached structure.

The data structure D_STR2 has an estimated primary user ID, time information, frequency band ID, and subcarrier No. , Wave source ID, contour center position, contour line power value and contour line radius need not be included, but include frequency band ID, position information indicating the contour line center position, contour line power value and contour line radius at least. It suffices to have a structure in which the frequency band ID, the position information indicating the center position of the contour lines, the power value of the contour lines, and the contour lines are associated with each other. This is because if the data structure D_STR2 includes at least the frequency band ID, the position information indicating the center position of the contour line, the power value of the contour line, and the contour line, the contour line of the received power created by the creating means 14 can be represented.

The data structure D_STR2 is used to represent the contour lines of the received power created by the power estimation device 1 (or any of the programs Prog_A and Prog_B) by the method described above. The data structure D_STR2 is input to the computer and stored in the storage means by the CPU. Then, the data structure D_STR2 is displayed on the display means by the CPU or printed on a paper medium or the like. Further, the data structure D_STR2 may be used to display an image showing contour lines of received power on the display means by the CPU that has executed the image software. Further, the data structure D_STR2 may be used by the CPU to calculate the power value of the radio wave at a position separated from the contour line of the received power by a desired distance.

In the above, the power estimation devices 1 and 1A create contour line CTRs of received power based on a plurality of monitor information MNTs detected by the plurality of terminal devices 2, and each of them is based on the created contour line CTRs of received power. Although it has been described that the received power at a place is estimated, the present invention is not limited to this, and the power estimation devices 1 and 1A are contour lines of the received power based on a plurality of monitor information MNTs by the above-mentioned method. You may just create a CTR. If a plurality of received power contour line CTRs having different power values P are created, the wave source S side of the received power contour line CTR having the largest power value P is based on the created multiple received power contour line CTRs. This is because the received power in the region REG2 between the region REG1 and the contour lines CTR of the two received powers having different power values P can be known, so that the received power in these regions REG1 and REG2 can be estimated.

Therefore, the power estimation device according to the embodiment of the present invention is a radio wave having a shared frequency shared by a plurality of terminal devices among a plurality of frequencies used for wireless communication in a target area for estimating the received power of the radio wave. A power estimation device that creates contour lines of the received power of the device, which is transmitted from a plurality of terminal devices and includes a plurality of monitor information including position information indicating the position of the terminal device and the received power of radio waves in the terminal device. From the extraction means for extracting k (k is an integer of 2 or more) monitor information including the maximum value of the received power, and weighted by the received power based on the k monitor information extracted by the extraction means. The average of the positions of the k terminal devices is obtained as the center of gravity of the received power, and of the k received powers, the received power is equal to or higher than the power value at the contour line of the received power to be created, and the received power of the received power. The distance between the terminal device located at the farthest position from the center of gravity and the center of gravity of the received power is obtained as the maximum distance, and the first has a circular shape centered on the center of gravity of the received power and the maximum distance as the radius. Centered on the contour line, the center point of the received power, and the second contour line having an elliptical shape with the maximum distance as the major axis, and centered on the center point of the received power, and the maximum distance from the center to one apex It suffices to provide a creation means for performing contour line creation processing for creating any of the third contour lines having the shape of the polygon as the distance as the contour line of the received power to be created.

Further, the wireless communication system according to the embodiment of the present invention may be provided with a power estimation device that creates a contour line CTR of received power.

Further, the program according to the embodiment of the present invention receives radio waves having a shared frequency shared by a plurality of terminal devices among a plurality of frequencies used for wireless communication in a target area for estimating the received power of radio waves. A program for causing a computer to create electric power contour lines, in which extraction means are transmitted from a plurality of terminal devices, and each of them has position information indicating the position of the terminal device and the received power of radio waves in the terminal device. The first step of extracting k (k is an integer of 2 or more) monitor information including the maximum value of the received power from the plurality of monitor information including the above, and the creating means are extracted in the first step. The average of the positions of the k terminal devices weighted by the received power based on the k monitor information is obtained as the center of gravity of the received power, and the power in the contour line of the received power to be created out of the k received powers. The distance between the terminal device that has received power equal to or greater than the value and is located farthest from the center of gravity of the received power and the center of gravity of the received power is calculated as the maximum distance, centered on the center of gravity of the received power, and , The first contour line having a circular shape with the maximum distance as the radius, the second contour line having an elliptical shape with the maximum distance as the major axis, and the center point of the received power center. Second, the contour line creation process is performed to create any of the third contour lines having a polygonal shape with the maximum distance as the distance from the center to one apex as the contour line of the received power to be created. You just have to let the computer perform the steps.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the description of the embodiments described above, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

The present invention applies to power estimators, wireless communication systems equipped with them, programs and data structures for running computers.

1A power estimation device, 2 terminal device. 3 base station, 4 wired cable, 10 wireless communication system, 11 receiving means, 12 recording means, 13, 13A extracting means, 14 creating means, 15 estimating means.

Claims (15)

A power estimation device that creates contour lines of the received power of radio waves having a shared frequency shared by multiple terminal devices among a plurality of frequencies used for wireless communication in the target area for estimating the received power of radio waves. ,
A k including the maximum value of the received power from a plurality of monitor information transmitted from the plurality of terminal devices and each including a position information indicating the position of the terminal device and the received power of the radio wave in the terminal device. An extraction means for extracting monitor information (k is an integer of 2 or more) and
The average of the positions of the k terminal devices weighted by the received power based on the k monitor information extracted by the extraction means is obtained as the center of gravity of the received power, and the k pieces of the received power are created. The distance between the terminal device having received power equal to or higher than the power value in the contour line of the received power to be received and located at the position farthest from the center of gravity of the received power and the center of gravity of the received power is obtained as the maximum distance. A first contour line having a circular shape centered on the center of gravity of the received power and having the maximum distance as the radius, and an elliptical shape centered on the center of gravity of the received power and having the maximum distance as the major axis. Create one of the second contour line having the contour line and the third contour line having a polygonal shape centered on the center of gravity of the received power and having the maximum distance as the distance from the center to one apex. A power estimation device including a creation means for performing contour line creation processing for creating contour lines of power received. The power estimation device according to claim 1, further comprising an estimation means for estimating the received power of radio waves at a desired location in the target area based on the contour lines of the received power created by the creating means. The extraction means has k new monitor information while removing at least the maximum value of the received power already extracted from the plurality of monitor information until the received power equal to or higher than the contour line power value of the received power to be created is exhausted. Repeatedly extracting
Claim 1 or claim, wherein the creating means performs the contour line creating process based on the extracted new k monitor information every time the new k monitor information is extracted by the extracting means. Item 2. The power estimation device according to item 2. The extraction means uses the first extraction method for extracting the new k monitor information while removing the k monitor information already extracted from the plurality of monitor information, or the k monitor information already extracted. Using the second extraction method that extracts the new k monitor information while removing only the maximum value of the received power included, until the received power equal to or higher than the contour line power value of the received power to be created disappears. , The new k monitor information is repeatedly extracted from the plurality of monitor information.
The creation means is
When the extraction means extracts the new k monitor information by the first extraction method, the first contour creation process for performing the contour creation process based on the new k monitor information and the above-mentioned The center of gravity of the received power is obtained based on the new k monitor information, and the monitor information included in both the already extracted k monitor information and the new k monitor information, and the new monitor information. One of the k-number monitor information and the second contour line creation process for creating the received power contour line by obtaining the maximum distance based on the received power center point is performed for the new k-number monitor information. It is performed every time the monitor information is extracted, and when the extraction means extracts the new k monitor information by the second extraction method, the first k monitor information is extracted every time the new k monitor information is extracted. The power estimation device according to claim 3, which performs the contour line creation process of 1. The first method is a method in which the extraction means extracts the new k pieces of monitor information by the first extraction method and the creation means performs the first contour line creation process, and the extraction means The second method is a method in which the k new monitoring information is extracted by the first extraction method and the creation means performs the second contour line creation process, and the extraction means is the second method. When the method of extracting the new k monitor information by the extraction method and the creating means performing the first contour line creating process is the third method.
The contour lines of the received power are created by using the first method when the calculation amount is set to the minimum, and are created by using the second method when the calculation amount is set to be the second smallest. The power estimation device according to claim 4, wherein the power estimation device is created by using the third method when the calculation amount is allowed to be the maximum calculation amount. The power estimation according to any one of claims 1 to 5, wherein the extraction means extracts the k pieces of monitor information so that each received power satisfies the reliability rate required according to the radio wave environment. Device. The creating means sets a power reduction distance in which the received power becomes a desired power value lower than the power value on the contour line of the received power already created in the region below the reception sensitivity of the radio wave in the terminal device, as a propagation model of the radio wave. The received power in a region equal to or lower than the reception sensitivity of the radio wave is obtained based on The power estimation device according to any one of claims 1 to 6, which is created as a contour line of the above. A wireless communication system including the power estimation device according to any one of claims 1 to 7. To make a computer create contour lines of radio wave reception power having a shared frequency shared by multiple terminal devices among multiple frequencies used for wireless communication in the target area for estimating radio wave reception power. It ’s a program,
The extraction means is transmitted from the plurality of terminal devices, and the maximum of the received power is obtained from a plurality of monitor information including the position information indicating the position of the terminal device and the received power of the radio wave in the terminal device. The first step of extracting k (k is an integer of 2 or more) monitor information including the value, and
The creating means obtains the average of the positions of the k terminal devices weighted by the received power based on the k monitor information extracted in the first step as the center of gravity of the received power, and the k pieces. Of the received power, the distance between the terminal device having received power equal to or higher than the power value in the contour line of the received power to be created and located at the position farthest from the center point of the received power and the center point of the received power. As the maximum distance, the first contour line having a circular shape centered on the center of gravity of the received power and having the maximum distance as the radius, centered on the center of gravity of the received power, and the maximum distance A second contour line having an elliptical shape with a major axis, and a third contour line having a polygonal shape centered on the center of gravity of the received power and having the maximum distance as the distance from the center to one apex. A program for causing a computer to execute a second step of performing contour line creation processing for creating any of the contour lines of the received power to be created. 9. The estimation means causes a computer to further perform a third step of estimating the received power of radio waves at a desired location in the target area based on the contour lines of the received power created in the second step. A program to be executed by the computer described in. The extraction means removes at least the maximum value of the received power already extracted from the plurality of monitor information until the received power equal to or higher than the contour line power value of the received power to be created disappears in the first step. Repeatedly extracting k new monitor information,
In the second step, each time the extraction means extracts the new k monitor information, the creating means performs the contour line creation process based on the extracted new k monitor information. The program to be executed by the computer according to claim 9 or 10. The extraction means uses the first extraction method for extracting the new k monitor information while removing the k monitor information already extracted from the plurality of monitor information, or the k monitor information already extracted. Using the second extraction method that extracts the new k monitor information while removing only the maximum value of the received power included, until the received power equal to or higher than the contour line power value of the received power to be created disappears. , The new k monitor information is repeatedly extracted from the plurality of monitor information.
The creating means is used in the second step.
When the extraction means extracts the new k monitor information by the first extraction method, the first contour creation process for performing the contour creation process based on the new k monitor information and the said The center of gravity of the received power is obtained based on the new k monitor information, and the monitor information included in both the already extracted k monitor information and the new k monitor information, and the new monitor information. One of the k-number monitor information and the second contour line creation process for creating the received power contour line by obtaining the maximum distance based on the received power center point is performed for the new k-number monitor information. Perform every time monitor information is extracted
A claim that when the extraction means extracts the new k monitor information by the second extraction method, the first contour line creation process is performed every time the new k monitor information is extracted. 11. The program for causing the computer to be executed. The first method is a method in which the extraction means extracts the new k pieces of monitor information by the first extraction method and the creation means performs the first contour line creation process, and the extraction means The second method is a method in which the k new monitoring information is extracted by the first extraction method and the creation means performs the second contour line creation process, and the extraction means is the second method. When the method of extracting the new k monitor information by the extraction method and the creating means performing the first contour line creating process is the third method.
The contour lines of the received power are created by using the first method when the calculation amount is set to the minimum, and are created by using the second method when the calculation amount is set to be the second smallest. The program for being executed by the computer according to claim 12, which is created by using the third method and when the calculation amount is allowed to be the maximum calculation amount. One of claims 9 to 13, wherein the extraction means extracts the k monitor information so that each received power satisfies the reliability rate required according to the radio wave environment in the first step. The program for causing the computer described in item 1 to execute. In the second step, the creating means has a power that becomes a receiving power that is a desired power value lower than the power value on the contour line of the received power that has already been created in the region below the reception sensitivity of the radio wave in the terminal device. The reduction distance is obtained based on the propagation model of the radio wave, and the contour line that is separated from the already created contour line of the received power by the said power reduction distance and has a shape similar to the contour line of the already created received power is the reception sensitivity of the radio wave. The program for causing the computer according to any one of claims 9 to 14 to execute, which is created as a contour line of the received power in the following area.

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