JP4559960B2 - Position detection system using IC tag - Google Patents

Description

  The present invention relates to a position detection system that detects the position of a “person” or “object” using an IC tag that performs ID identification without contact.

In recent years, interest in position detection systems that detect the position of “people” and “things” using IC tags in various locations such as exhibition halls, offices, warehouses, and factories is increasing.
For example, at an exhibition hall or office, an IC tag is attached to an admission card or an employee ID card, and the location of the user or employee is detected by a receiver installed on the wall or ceiling in the facility or office.
Or, in warehouses and factories, IC tags (asset tags) are affixed to fixed assets such as stocks and machinery, and IC tags (location tags) are affixed to walls and pillars in warehouses and factories, and staff members carry handy readers. Then, the asset tag and the location tag are read to detect the presence of an inventory item or fixed asset and the installation location.

However, in the case of an exhibition hall or an office, it is necessary to install a large number of receivers in the facility or office, and the construction and maintenance of the system is very expensive.
In the case of warehouses and factories, staff members walk around the warehouses and factories and read information by holding the handy reader over asset tags and place tags attached to various places, which requires a lot of labor and time.

On the other hand, since April 2007, in order to send location information to the police and the fire department at the time of an emergency call from a mobile phone such as the 110th call, it is obliged to install a GPS function on the mobile phone according to the communication equipment rules of the Ministry of Internal Affairs and Communications. It is done.
In addition, GPS mobile phones capable of so-called pedestrian navigation such as route search to a destination and route guidance are rapidly spreading.
However, GPS mobile phones are difficult to measure in places such as indoor areas where radio waves from satellites do not reach.
For this reason, location information cannot be transmitted in an emergency call from a GPS mobile phone in an underground shopping area where there are many users. In addition, the pedestrian navigation service cannot be performed.

By the way, the present applicant communicates with IC tags disclosed in International Publication No. 2005-069499 using a probe signal having a short reach distance, detects IC tags within the same close range and their arrangement order, and detects relative positions. An IC tag location recognition apparatus and method for recognizing relationships has already been filed.
If position information is given to an arbitrary IC tag within the same close range, the position of the IC tag can be individually specified.
International Publication No. 2005-0669499

A problem to be solved is a point as described above, the present invention is, by providing the location information to the already Application of the IC tag does not require a work reading by a number of receivers and staff, using the IC tag The first object of the present invention is to provide a position detection system, and the second object is to enable the transmission of position information and pedestrian navigation even in places where radio waves from satellites do not reach.

Therefore, the present invention is based on the first communication by radio in which the reader / writer and the IC tag have a long distance in the communication area A and the probe signal in which the IC tags are relatively short in the communication area B (<A). Make a second communication,
In the first communication, probe signal transmission command processing for instructing the IC tag to transmit a probe signal from the reader / writer, and first ID reading processing in which the reader / writer reads its own ID information from the IC tag. When carried out the second ID reading process for reading the ID information of the other party from the IC tag it receives a probe signal stored in the memory, at the same time,
In the second communication, a probe signal transmission process for transmitting a probe signal from an IC tag to another IC tag, and an ID storage for storing in a memory the ID information of the counterpart IC tag from which the IC tag received the probe signal In the configuration for performing processing,
A fixed tag for installing the IC tag at a fixed point, a moving tag to be attached to a moving body,
Divided into
Further, the detection device that instructs the reader / writer includes a position table that stores ID information of the fixed tag in association with the coordinate address, and a moving body table that stores ID information of the moving tag in association with the moving body number. make,
Referring to these tables, the mobile body number to which the corresponding movement tag is attached is identified from the ID information of the movement tag itself read from the movement tag in the first ID reading process,
The coordinate address where the corresponding fixed tag is installed is specified from the ID information of the partner (fixed tag) that has received the probe signal, which is stored in the memory of the moving tag in the second ID reading process, and the moving object is determined from this coordinate number. The first feature is to detect the position of .

  In addition, the mobile tag includes a connection circuit with a portable navigation system, the ID information of the fixed tag of the other party that has received the probe signal is transmitted to the portable navigation system, and the latitude / longitude point where the fixed tag is installed is determined as the GPS position. Recognition as information is a second feature.

According to the present invention, by installing a large number of fixed tags that are cheaper and simpler to install than the receiver in the communication area A of the reader / writer, the short distance communication between the fixed tag and the moving tag becomes possible at any place. Therefore, it is not necessary to install many receivers.
In addition, since the moving tag that has received the probe signal automatically acquires the ID information of the fixed tag of the other party and detects the position, there is no need for the attendant to hold the handy reader and read the ID information as in the prior art.

  In addition, a fixed tag is installed at the latitude and longitude points, and the ID information of the fixed tag from which the moving tag has received the probe signal is transmitted to an external device such as a GPS mobile phone via a connection circuit with the mobile navigation, so that the satellite can Positioning is possible even in places where the radio waves do not reach.

  Embodiments of the present invention will be described below.

FIG. 1 shows a configuration diagram of a position detection system using an IC tag implementing the present invention.
In the position detection system using the IC tag, in the communication area A, the reader / writer 1 and the IC tag 2 perform the first communication by the long-distance radio according to the command of the detection device 3, and the communication within the communication area B (<A). The second communication is performed by the probe signal having a relatively short distance between the IC tags 2.
The first communication includes downlink communication in which a request signal is transmitted from the reader / writer 1 to the IC tag 2 and uplink communication in which a response signal is transmitted from the IC tag 2 to the reader / writer 1.
The request signal includes a unique ID read command for reading a unique ID from the IC tag 2, a probe signal transmission command for instructing the IC tag 2 to transmit a probe signal, and an adjacent ID read command for reading an adjacent ID from the IC tag 2.
The response signal includes a unique ID response that responds to the unique ID of the IC tag 2 and an adjacent ID response that responds to the adjacent ID of the IC tag 2.
The second communication includes mutual link communication in which a probe signal transmitted from the IC tag 2 is received by the IC tag 2 in the same communication area B.

As the probe signal, a non-directional radio wave, magnetism, sound, light or the like that attenuates in proportion to the distance is used.
When radio waves are used for the probe signal, different modulation methods may be employed depending on the communication, for example, the first communication is performed using the ASK modulation method and the second communication is performed using the FSK modulation method.
Similarly, different frequency bands may be used depending on the communication, for example, the first communication is performed in the 13.56 MHz band or 2.45 GHz band, and the second communication is performed in the 125 kHz band or 13.56 MHz band.

The IC tag 2 can be used in two ways: a fixed tag a and a moving tag b. The fixed tag a is installed at a fixed point of coordinates in which a straight line or a plane is divided at equal intervals, and the moving tag b is “person” or “thing”. Attached to a moving body such as
It is desirable that the fixed tags a are installed at intervals similar to the size of the moving object to which the moving tag b is attached. In addition, the reach distance of the probe signal can be adjusted, and it is preferable to adjust the distance so as to be approximately the same as the installation interval of the fixed tag a.

When detecting the position, the reader / writer 1 is held in advance over the fixed tag a set at a fixed point of coordinates, and the ID is sequentially read, and the read ID is associated with the coordinate address and stored in the position table of the detection device 3 .
Alternatively, the coordinate address may be written in order by holding the reader / writer 1 over the fixed tag a installed at a fixed point of coordinates, and the fixed tag a may be called by designating the coordinate address instead of the ID.
Further, the ID is sequentially read by holding the reader / writer 1 over the moving tag b attached to the moving body in advance, and the read ID is stored in the moving body table of the detecting device 3 in association with the moving body number.
Alternatively, the moving body number may be written by holding the reader / writer 1 over the moving tag b attached to the moving body, and the moving tag b may be called by specifying the moving body number instead of the ID.

FIG. 2 shows a block diagram of an IC tag implementing the present invention.
Although the figure shows a configuration when radio waves are used for the probe signal, the present invention does not limit the probe signal to radio waves.
The IC tag 2 includes a downlink / uplink communication unit including a rectifier circuit 21, a demodulation circuit 22, a modulation circuit 23, and a clock circuit 24 connected to the antenna T via the circulator 20, and a control unit including a CPU 25 and a memory 26. A mutual link communication unit including a receiving circuit 27 and a transmitting circuit 28 connected to the antenna T via the circulator 20, and connected to an external device such as a GPS mobile phone via the interface circuit 29.
In the figure, the mutual link communication unit is provided with the receiving circuit 27 and the transmitting circuit 28, but only one of them may be dedicated for transmission or reception.

As described above, when the reader / writer 1 modulates a request signal to the IC tag 2 and emits a radio wave, an induced voltage is generated in the antenna T of the IC tag 2.
The induced voltage is rectified by the rectifier circuit 21 to serve as an operating power supply, and the clock circuit 24 generates a clock for IC synchronization using the frequency.
Thus, when power and clock are supplied to the IC circuit, the demodulator circuit 22 in the forward direction of the circulator 20 demodulates the request signal while synchronizing with the clock, and the CPU 25 analyzes it and analyzes the response signal according to the request signal. Is modulated by the modulation circuit 23 and transmitted to the reader / writer 1 via the antenna T in the forward direction of the circulator 20.
The IC tag 2 detects the radio wave of the reader / writer 1 to generate an excitation voltage, and rectifies it to obtain an operating power source. In order to stably secure a relatively long communication distance, an active type with a built-in battery may be used.

At the same time, the transmitting circuit 28 transmits a probe signal to the neighboring IC tag 2 via the circulator 20, and the receiving circuit 27 of the neighboring IC tag 2 receives it to detect the signal strength, and performs A / D conversion. The signal strength is input to the CPU 25.
When the signal strength is equal to or higher than a predetermined level, the CPU 25 stores the ID of the transmission source IC tag 2 transmitted from the reader / writer 1 in the memory 26 as the adjacent ID.

  The probe signal is transmitted only by either one of the fixed tag a and the moving tag b, and only received by the other. The following is a case where the fixed tag a is dedicated for transmission and the mobile tag b is dedicated for reception. To do.

When a position table or a moving body table is created in the detection device 3 in advance for position detection, the IDs of the fixed tag a and the moving tag b are known, but otherwise are unknown.
In this case, in order to search for an unknown ID, a request signal is transmitted with the ID reading range specified as a response permission condition for the fixed tag a and the moving tag b, and only tags that meet the response permission condition respond. And anti-collision (collision prevention) control with the reader / writer 1.
At this time, when a request signal is transmitted to the moving tag b (or the fixed tag a), the fixed tag a is previously prevented so that the fixed tag a (or the moving tag b) having the ID in the designated reading range does not respond. A mode for prohibiting a response to the reader / writer 1 is set for (or the moving tag b). Alternatively, the fixed tag a and the moving tag b may have a “fixed” or “moved” identification flag, and this identification flag may be designated in addition to the ID reading range as a response permission condition.

If the responses collide, not only cannot the information be read / written, but in the worst case, the data of the fixed tag a and the moving tag b may be destroyed at the time of writing.
Therefore, reading / writing of information is performed only when the fixed tag a and the moving tag b respond alone by anti-collision control.
To identify whether there are multiple or single responses, the bit pattern of the received signal will be disturbed if the responses are duplicated, so check the bit pattern of the received signal using a cyclic check code (CRC) to detect errors It is determined that there were multiple responses.

In the free space, as shown in FIG. 3, when the transmission power Pt (W) of the probe signal transmitted from the transmission-side fixed tag a is constant, the reception voltage E (V / m) received by the reception-side moving tag b. ) Increases in inverse proportion to the distance d (m) between the fixed tag a on the transmission side.
As a result, the received voltage E received by the receiving-side mobile tag b increases as the distance d between the transmitting-side fixed tag a decreases (d1>d2> d3) (E1 <E2 <E3). Become).
Therefore, when the reception voltage E at a level adjusted in advance is detected, it can be seen that the moving tag b is in the vicinity of the coordinate point where the source fixed tag a is installed.

FIG. 4 shows a sequence flow of position detection.
A case will be described below where a position table is created in advance and the ID of the fixed tag a is known, but the ID of the moving tag b is unknown.
First, the reader / writer 1 refers to the position table, designates IDs in the order of addresses, and transmits a probe signal transmission command (probe signal transmission command processing) .
On the other hand, the ID designated by the moving tag b is temporarily stored in the memory 26 as the adjacent ID, and the fixed tag a having the designated ID simultaneously transmits a probe signal to the neighboring moving tag b.
Here, the moving tag b that has received the probe signal of a predetermined level or higher determines and stores the adjacent ID temporarily stored in the memory 26 (ID storage processing) .
Next, the reader / writer 1 designates the ID reading range and transmits a unique ID reading command.
On the other hand, the movement tag b in the designated reading range returns its own ID (first ID reading process) .
Next, the reader / writer 1 designates the returned ID and transmits an adjacent ID read command.
On the other hand, the movement ID b of the designated ID returns the adjacent ID that is confirmed and stored in the memory 26 (second ID reading process) .
Finally, the moving body number to which the moving tag b is attached is identified from the ID of the moving tag b collected by the detection device 3 via the reader / writer 1, and the coordinate address where the fixed tag a is installed is referred to by referring to the adjacent ID. Identify.

The operation of the reader / writer 1 will be described with reference to the flowchart of FIG.
A case will be described below where a position table is created in advance and the ID of the fixed tag a is known, but the ID of the moving tag b is unknown.
The anti-collision control performed in the method is based on the method already disclosed by the present applicant in Japanese Patent Application No. 2004-38621. However, other methods may be used, and the present invention is not limited to this.
First, in step 101, the ID of the fixed tag a is read from the position table in order of address, and in the next step 102, the ID is specified and a probe signal transmission command is transmitted to the fixed tag a.
In the next step 103, it is determined whether or not the position table has been completed. If it has been completed, the process proceeds to the next step 104. If not, the process returns to step 101 to read the next ID.

In the next step 104, the maximum reading range is designated as a response permission condition, and in the next step 105, a unique ID reading command is transmitted to the moving tag b.
In the next step 106, it is determined whether or not there is a response from the moving tag b. If there is a response, the process proceeds to the next step 107. Otherwise, the process proceeds to the previous step 111.
In the next step 107, it is determined whether the response is a single response or a plurality of responses. If the response is a single response, the process proceeds to the next step 108;
In the next step 108, the unique ID of the responding movement tag b is read, and in the next step 109, the ID is designated and an adjacent ID read command is transmitted to the movement tag b.
The adjacent ID of the moving tag b responded in the next step 110 is read, and if there are a plurality of IDs, they are sequentially stored in the memory.
Expanding the next step 111 read range, it is determined whether reading preparative range in the next step 112 is over the maximum read range.
If the maximum reading range is exceeded, the process ends. Otherwise, the process returns to step 105 to transmit the next unique ID reading command to the movement tag b.
In step 113, the reading range is reduced, and the process returns to step 105 to transmit the next unique ID reading command to the moving tag b.

The operation of the IC tag 2 will be described with reference to the flowchart of FIG.
The IC tag 2 is activated when the request signal of the reader / writer 1 is received. First, in step 201, it is determined whether or not the request signal is a unique ID read command. If it is a unique ID read command, the process proceeds to the next step 202. Otherwise, go to step 204.
In the next step 202, it is determined whether or not the own ID is within the designated reading range. If it is within the reading range, the process proceeds to the next step 203, and if not, the process is terminated.
In the next step 203, the user ID is returned to the reader / writer 1 and the process is terminated.

In step 204, it is determined whether the request signal is a probe signal transmission command. If the request signal is a probe signal transmission command, the process proceeds to the next step 205. Otherwise, the process proceeds to step 212.
In the next step 205, it is determined whether or not the own ID is designated. If designated, the process proceeds to the next step 206. Otherwise, the process proceeds to step 207.
In the next step 206, a probe signal is transmitted to the other IC tag 2, and the process is terminated.
In step 207, the ID designated by the reader / writer 1 is temporarily stored in the memory 26 as an adjacent ID.
In the next step 208, it is determined whether or not a probe signal transmitted from another IC tag 2 has been detected. If detected, the process proceeds to the next step 209. Otherwise, the process proceeds to step 211.
In the next step 209, the adjacent ID temporarily stored in the memory 26 is confirmed and stored, and in the next step 210, the adjacent ID is output to the external device via the interface circuit 29.
In step 211, the storage state of the adjacent ID temporarily stored in the memory 26 is canceled.

In step 212, it is determined whether the request signal is an adjacent ID read command. If the request signal is an adjacent ID read command, the process proceeds to the next step 213, and if not, the process ends.
In the next step 213, it is determined whether or not the own ID is designated. If designated, the process proceeds to the next step 214, and if not, the process is terminated.
In the next step 214, when there are a plurality of adjacent IDs confirmed and saved in the memory 26, they are read in order and returned to the reader / writer 1, and in the next step 215, the saved state of all neighboring IDs confirmed and saved in the memory 26 is canceled. Then, the process ends.

The first embodiment of the present invention will be described below.
In the present embodiment, the positions of items randomly arranged on a plane are detected. As shown in FIG. 7, the plane is divided into a grid shape, and for example, 7, 6, 3, 5 is fixed at the center of the grid. A tag a is placed, and items with 2, 4, 1, and 8 moving tags b attached thereto are arranged at random.
In the communication area A, the reader / writer 1 and the fixed tag a and the moving tag b perform the first wireless communication with the communication distance number m, and in the communication area B, the fixed tag a and the moving tag b are the communication distance number cm. The second communication is performed using the probe signal.

FIG. 8 shows a sequence flow of this embodiment.
A case will be described below where a position table is created in advance and the ID of the fixed tag a is known, but the ID of the moving tag b is unknown.

The reader / writer 1 first designates 7 and transmits a probe signal transmission command.
On the other hand, all the moving tags b temporarily store 7 as an adjacent ID in the memory 26, and the 7 fixed tags a transmit a probe signal.
On the other hand, the second moving tag b receives the probe signal, and confirms and stores the temporarily stored 7.
4, 1 and 8 which do not receive the probe signal cancel the temporary storage.
Next, 6 is designated and a probe signal transmission command is transmitted.
On the other hand, all the moving tags b temporarily store 6 as an adjacent ID in the memory 26, and the 6 fixed tags a transmit a probe signal.
On the other hand, the second moving tag b receives the probe signal, and confirms and saves the temporarily saved 6 in addition to the previous 7.
4, 1 and 8 which do not receive the probe signal cancel the temporary storage.
Next, 3 is designated and a probe signal transmission command is transmitted.
On the other hand, all the moving tags b temporarily store 3 as the adjacent ID in the memory 26, and the 3 fixed tags a transmit a probe signal.
On the other hand, the 4 and 1 movement tags b receive the probe signal, and the temporarily stored 3 is confirmed and stored. 2 and 8 that do not receive the probe signal cancel the temporary storage.
Next, 5 is designated and a probe signal transmission command is transmitted.
On the other hand, all the moving tags b temporarily store 5 as the adjacent ID in the memory 26, and the fixed tag a of 5 transmits a probe signal.
On the other hand, the movement tags b of 1 and 8 receive the probe signal, and 1 confirms and saves 5 temporarily saved by 1 and 8 in addition to the previous 3.

Next, the reader / writer 1 designates the maximum reading range 1 to 8 and transmits a unique ID reading command to the moving tag b.
In response to this, all the movement tags b respond.
Next, since there are a plurality of responses, the reading range is reduced and a unique ID reading command for reading ranges 1 to 4 is transmitted.
On the other hand, the movement tags b of 2, 4, 1 respond.
Next, since there are a plurality of responses, the reading range is further reduced and a unique ID reading command for the reading ranges 1 to 2 is transmitted.
On the other hand, 2 and 1 movement tags b respond.
Next, since there are a plurality of responses, the reading range is further reduced and a unique ID reading command for the reading ranges 1 to 1 is transmitted.
On the other hand, only one moving tag b responds.
Here, since the response is single, 1 is read as the detection number, and then 1 is designated and the adjacent ID read command is transmitted.
On the other hand, 3 and 5 stored in the memory 26 by one moving tag b are returned, and the fixed storage is canceled.
Here, 3 and 5 are read as adjacent IDs, and then the reading range is shifted and a unique ID reading command for reading ranges 2 and 2 is transmitted.
In contrast, only the second moving tag b responds.
Here, since the response is single, 2 is read as a detection number, and next, 2 is specified and an adjacent ID read command is transmitted.
On the other hand, the second moving tag b returns 7 and 6 stored in the memory 26 and cancels the fixed storage.
Here, 7 and 6 are read as adjacent IDs, and then the reading range is expanded and a unique ID reading command of reading ranges 3 to 4 is transmitted.
On the other hand, only 4 moving tags b respond.
Here, since the response is single, 4 is read as the detection number, and then 4 is designated and the adjacent ID read command is transmitted.
On the other hand, 3 stored in the memory 26 is returned by the 4 moving tags b, and the fixed storage is canceled.
Here, 3 is read as the adjacent ID, and then the reading range is expanded and a unique ID reading command of the reading range 5 to 8 is transmitted.
On the other hand, only 8 moving tags b respond.
Here, since the response is single, 8 is read as a detection number, and next, 8 is designated and an adjacent ID read command is transmitted.
On the other hand, the 8 moved tag b returns 5 stored in the memory 26 and cancels the confirmed storage.
Here, 5 is read as the adjacent ID, and then the reader / writer 1 expands the reading range, but exceeds the maximum reading range 1 to 8, and thus ends the reading of the unique ID and the adjacent ID.

Finally, the position of the item to which the moving tag b is attached is specified with reference to the adjacent ID of the moving tag b collected by the detection device 3 via the reader / writer 1.
That is, since the adjacent ID of one moving tag b is 3 and 5, the item attached with the one moving tag b has a grid with the fixed tag a 3 if priority is given to the adjacent ID that comes first, otherwise It turns out that it exists in the boundary of the grid which installed the fixed tag a of 3 and 5.
Similarly, it can be seen that the second moving tag b is in the seventh cell, or the boundary between the seventh and sixth cells, the fourth moving tag b is in the third cell, and the eighth moving tag b is in the fifth cell.

The second embodiment of the present invention will be described below.
In the present embodiment, the seat of the examinee is detected at a test venue or the like, and as shown in FIG. 9, for example, 7, 6, 3, and 5 fixed tags a are installed on the desk in the venue, and 2 are installed in the seat. A test taker with an examination slip attached with movement tags b of 4, 1, 8 is seated.
In the communication area A, the reader / writer 1 and the fixed tag a and the moving tag b perform the first wireless communication with the communication distance number m, and in the communication area B, the fixed tag a and the moving tag b are the communication distance number cm. The second communication is performed using the probe signal.
In addition to this, the present embodiment can be applied to a scene in which the fixed tag a and the moving tag b correspond one-to-one, such as a piece placed on the grid of the shogi board and a meteorite placed on the board of the board.

FIG. 10 shows a sequence flow of the present embodiment.
A case will be described below where a position table is created in advance and the ID of the fixed tag a is known, but the ID of the moving tag b is unknown.

The reader / writer 1 first designates 7 and transmits a probe signal transmission command.
On the other hand, all the moving tags b temporarily store 7 as an adjacent ID in the memory 26, and the 7 fixed tags a transmit a probe signal.
On the other hand, the second moving tag b receives the probe signal, and confirms and stores the temporarily stored 7.
4, 1 and 8 which do not receive the probe signal cancel the temporary storage.
Next, 6 is designated and a probe signal transmission command is transmitted.
On the other hand, all the moving tags b temporarily store 6 as an adjacent ID in the memory 26, and the 6 fixed tags a transmit a probe signal.
On the other hand, 4 moving tags b receive the probe signal and 6 is temporarily stored.
2, 1, and 8 that do not receive the probe signal cancel the temporary storage.
Next, 3 is designated and a probe signal transmission command is transmitted.
On the other hand, all the moving tags b temporarily store 3 as the adjacent ID in the memory 26, and the 3 fixed tags a transmit a probe signal.
On the other hand, one moving tag b receives the probe signal, and confirms and stores 3 temporarily stored.
2, 4, and 8 that do not receive the probe signal cancel the temporary storage.
Next, 5 is designated and a probe signal transmission command is transmitted.
In contrast, 8 moving tags b temporarily store 5 as an adjacent ID in the memory 26, and 5 fixed tags a transmit probe signals.
On the other hand, the 8 movement tags b receive the probe signal, and the temporarily stored 5 is confirmed and stored.
2, 4, and 1 that do not receive the probe signal cancel the temporary storage.

Next, the reader / writer 1 designates the maximum reading range 1 to 8 and transmits a unique ID reading command to the moving tag b.
In response to this, all the movement tags b respond.
Next, since there are a plurality of responses, the reading range is reduced and a unique ID reading command for reading ranges 1 to 4 is transmitted.
On the other hand, the movement tags b of 2, 4, 1 respond.
Next, since there are a plurality of responses, the reading range is further reduced and a unique ID reading command for the reading ranges 1 to 2 is transmitted.
On the other hand, 2 and 1 movement tags b respond.
Next, since there are a plurality of responses, the reading range is further reduced and a unique ID reading command for the reading ranges 1 to 1 is transmitted.
On the other hand, only one moving tag b responds.
Here, since the response is single, 1 is read as the detection number, and then 1 is designated and the adjacent ID read command is transmitted.
In response to this, 3 is returned by one moving tag b in the memory 26, and the fixed saving is canceled.
Here, 3 is read as an adjacent ID, and then the reading range is shifted and a unique ID reading command of reading range 2-2 is transmitted.
In contrast, only the second moving tag b responds.
Here, since the response is single, 2 is read as a detection number, and next, 2 is specified and an adjacent ID read command is transmitted.
In response to this, the second moving tag b returns 7 stored in the memory 26 and cancels the confirmed storage.
Here, 7 is read as an adjacent ID, and then the reading range is expanded and a unique ID reading command of reading range 3 to 4 is transmitted.
On the other hand, only 4 moving tags b respond.
Here, since the response is single, 4 is read as the detection number, and then 4 is designated and the adjacent ID read command is transmitted.
On the other hand, 6 that the moving tag b of 4 saved in the memory 26 is returned, and the fixed saving is canceled.
Here, 6 is read as the adjacent ID, and then the reading range is expanded and a unique ID reading command of reading range 5 to 8 is transmitted.
On the other hand, only 8 moving tags b respond.
Here, since the response is single, 8 is read as a detection number, and next, 8 is designated and an adjacent ID read command is transmitted.
On the other hand, the 8 moved tag b returns 5 stored in the memory 26 and cancels the confirmed storage.
Here, 5 is read as the adjacent ID, and then the reader / writer 1 expands the reading range, but exceeds the maximum reading range 1 to 8, and thus ends the reading of the unique ID and the adjacent ID.

Finally, referring to the adjacent ID of the moving tag b collected by the detection device 3 via the reader / writer 1, the seat of the examinee holding the examination slip attached with the moving tag b is specified.
That is, since the adjacent ID of one moving tag b is 3, it can be seen that a test taker who has an examination slip attached with one moving tag b is in a seat where three fixed tags a are installed.
Similarly, it can be seen that 2 is in a seat with 7, 4 is 6, and 8 is in a seat with 5 fixed tags a.

The third embodiment of the present invention will be described below.
In this embodiment, the location of a pedestrian in an underground shopping area where radio waves from a satellite do not reach is detected. As shown in FIG. A pedestrian with 2 movement tags b is arbitrarily moved in the underground shopping area.
In the communication area A, the reader / writer 1 and the fixed tag a and the moving tag b perform the first wireless communication with a communication distance of m, and in the communication area B, the fixed tag a and the moving tag b have a communication distance of several tens. A second communication is performed using a probe signal of 1 to 2 m from cm.

FIG. 12 shows a sequence flow of the present embodiment.
Hereinafter, a case where a position table and a moving body table are created in advance and the IDs of the fixed tag a and the moving tag b are known will be described.

The reader / writer 1 first designates 7 and transmits a probe signal transmission command.
On the other hand, the two moving tags b temporarily store 7 as the adjacent ID in the memory 26, and the seven fixed tags a transmit a probe signal.
On the other hand, there is no moving tag b that receives the probe signal.
2 that does not receive the probe signal cancels the temporary storage.
Next, 6 is designated and a probe signal transmission command is transmitted.
On the other hand, the two moving tags b temporarily store 6 as the adjacent ID in the memory 26, and the six fixed tags a transmit a probe signal.
On the other hand, the second moving tag b receives the probe signal, and confirms and stores 6 temporarily stored.
Next, 3 is designated and a probe signal transmission command is transmitted.
On the other hand, the two moving tags b temporarily store 3 as the adjacent ID in the memory 26, and the three fixed tags a transmit a probe signal.
On the other hand, the second moving tag b receives the probe signal, and confirms and saves the temporarily stored 3 in addition to the previous 6.
Next, 5 is designated and a probe signal transmission command is transmitted.
On the other hand, the two moving tags b temporarily store 5 as the adjacent ID in the memory 26, and the five fixed tags a transmit a probe signal.
On the other hand, there is no moving tag b that receives the probe signal.
2 that does not receive the probe signal cancels the temporary storage.

Next, the reader / writer 1 designates 2 for the moving tag b and transmits an adjacent ID read command.
On the other hand, the second moving tag b returns 6 and 3 stored in the memory 26 as the adjacent ID, and cancels the fixed storage.
Here, the reader / writer 1 reads 6 and 3 as adjacent IDs, and the reading of the adjacent ID is completed.

Finally, the location of the pedestrian who attached the moving tag b is specified with reference to the adjacent ID of the moving tag b collected by the detection device 3 via the reader / writer 1.
That is, since the adjacent ID of the second moving tag b is 6, 3, the pedestrian attached with the second moving tag b is the point where the fixed tag a of 6 is installed when priority is given to the adjacent ID that comes first, otherwise It can be seen that is at the boundary of points where the fixed tags a of 6 and 3 are installed.

The fourth embodiment of the present invention will be described below.
In the present embodiment, a pedestrian navigation service is performed in an underground shopping area where radio waves from a satellite do not reach. As shown in FIG. 13, for example, fixed tags a of 7, 6, 3, 5 are provided at latitude and longitude points of the underground shopping center. The pedestrian with the portable navigation 4 installed and attached with the 2 movement tags b in the underground shopping area freely walks around.
In the communication area A, the reader / writer 1 and the fixed tag a and the moving tag b perform the first wireless communication with a communication distance of m, and in the communication area B, the fixed tag a and the moving tag b have a communication distance of several tens. A second communication is performed using a probe signal of 1 to 2 m from cm.

FIG. 14 shows a sequence flow of the present embodiment.
Hereinafter, a case where a position table and a moving body table are created in advance and the IDs of the fixed tag a and the moving tag b are known will be described.

The reader / writer 1 first designates 7 and transmits a probe signal transmission command.
On the other hand, the two moving tags b temporarily store 7 as the adjacent ID in the memory 26, and the seven fixed tags a transmit a probe signal.
On the other hand, there is no moving tag b that receives the probe signal.
2 that does not receive the probe signal cancels the temporary storage.
Next, 6 is designated and a probe signal transmission command is transmitted.
On the other hand, the two moving tags b temporarily store 6 as the adjacent ID in the memory 26, and the six fixed tags a transmit a probe signal.
On the other hand, the two moving tags b receive the probe signal and output 6 temporarily stored in the memory 26 via the interface circuit 29 to the portable navigation 4.
The portable navigation 4 recognizes the latitude / longitude point where the fixed tag a of 6 is installed as GPS position information, and updates the navigation screen.
Next, 3 is designated and a probe signal transmission command is transmitted.
On the other hand, the two moving tags b temporarily store 3 as the adjacent ID in the memory 26, and the three fixed tags a transmit a probe signal.
On the other hand, the second moving tag b receives the probe signal, and outputs 3 temporarily stored in the memory 26 via the interface circuit 29 to the portable navigation 4 following the previous 6.
The portable navigation 4 recognizes the latitude / longitude point where the three fixed tags a are installed as new GPS position information, and updates the navigation screen.
Next, 5 is designated and a probe signal transmission command is transmitted.
On the other hand, the two moving tags b temporarily store 5 as the adjacent ID in the memory 26, and the five fixed tags a transmit a probe signal.
On the other hand, there is no moving tag b that receives the probe signal.
2 that does not receive the probe signal cancels the temporary storage.
The above processing is repeated to continuously output the latest position information to the portable navigation 4.
As a result, positioning is possible even in a place where radio waves from the satellite do not reach, and services such as location information transmission and pedestrian navigation in an emergency can be seamlessly performed both indoors and outdoors.
Moreover, since the power required for positioning is supplied from the reader / writer 1, the power consumption of the portable navigation 4 can be greatly reduced as compared with the prior art.

It is a block diagram of the position detection system using the IC tag which implemented this invention. It is a block diagram of the IC tag which implemented this invention. It is a figure which shows the change of the receiving voltage E by the distance d. It is a sequence flow of position detection. It is a flowchart explaining operation | movement of a reader / writer. It is a flowchart explaining operation | movement of an IC tag. It is a block diagram of 1st Example. It is a sequence flow of 1st Example. It is a block diagram of 2nd Example. It is a sequence flow of 2nd Example. It is a block diagram of 3rd Example. It is a sequence flow of 3rd Example. It is a block diagram of 4th Example. It is a sequence flow of 4th Example.

DESCRIPTION OF SYMBOLS 1 Reader / writer 2 IC tag 20 Circulator 21 Rectifier circuit 22 Demodulator circuit 23 Modulator circuit 24 Clock circuit 25 CPU
26 memory 27 receiving circuit 28 transmitting circuit 29 interface circuit 3 detection device 4 portable navigation T antenna a fixed tag b moving tag

Claims (7)

In the communication area A, the reader / writer and the IC tag communicate with each other over a long distance wirelessly,
In the communication area B (<A), the IC tags perform a second communication with a probe signal having a relatively short distance,
In the first communication,
Probe signal transmission command processing for commanding the probe signal from the reader / writer to the IC tag;
Reader / writer
A first ID reading process for reading own ID information from the IC tag;
A second ID reading process for reading the ID information of the other party receiving the probe signal stored in the memory from the IC tag ;
At the same time ,
In the second communication,
Probe signal transmission processing for transmitting a probe signal from an IC tag to another IC tag;
An ID storage process for storing, in a memory, ID information of the IC tag of the other party that the IC tag has received the probe signal;
In the configuration to perform
A fixed tag for installing the IC tag at a fixed point;
A moving tag to be attached to the moving body;
Divided into
Furthermore, to the detection device that commands the reader / writer,
A position table storing ID information of fixed tags in association with coordinate addresses;
A mobile body table storing ID information of mobile tags in association with mobile body numbers;
Create
With reference to these tables, the mobile body number to which the corresponding movement tag is attached is identified from the ID information of the movement tag itself read from the movement tag in the first ID reading process,
In the second ID reading process, the coordinate address where the fixed tag corresponding to the partner (fixed tag) that received the probe signal is stored is identified from the ID information stored in the memory of the moving tag ,
A position detection system using an IC tag that detects the position of a moving object from the coordinate number . Hold the reader / writer in advance and set the coordinate address to the fixed tag.
The moving body number on the moving tag,
Write
From this, the moving body number is directly read from the moving tag to identify the moving body to which the moving tag is attached,
The position detection system using an IC tag according to claim 1, wherein the coordinate address is directly read from the fixed tag to identify the coordinate address where the fixed tag is installed. The moving tag comprises a connection circuit of a portable navigation,
2. The IC according to claim 1, wherein the ID information of the fixed tag of the other party receiving the probe signal is transmitted to a portable navigation system and the latitude / longitude point where the fixed tag is installed is recognized as GPS position information. Position detection system using tags. The reach of the probe signal is adjustable ,
2. The position detection system using an IC tag according to claim 1, wherein the position is adjusted to substantially the same length as a fixed point interval where the fixed tag is installed. Positioning system using IC tags according to claim 1, wherein the distance between the fixed points installed the fixed tag is set to different lengths depending on the size of the movable body. 2. The position detection using an IC tag according to claim 1, wherein the probe signal uses a non-directional radio wave, magnetism, sound, or light that attenuates in proportion to a distance as a propagation medium. system. In the first and second ID reading processes, the coordinate address where the fixed tag is installed is identified from its own ID information read from the fixed tag,
2. The position detection system using an IC tag according to claim 1, wherein a moving body to which a moving tag is attached is identified by referring to ID information of a partner who has received a probe signal and stored in a memory.

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