CN104853433A - Indoor positioning method, indoor positioning system and computer readable medium - Google Patents

Abstract

The invention discloses an indoor positioning system, which comprises at least one signal source arranged in an indoor environment with a plurality of training points, and a storage device and a positioning device which are coupled. The signal source has a plurality of power levels and transmits a wireless signal according to one of the power levels. The storage device stores a first signal strength for each training point and a second signal strength for at least one adaptation point in the training points. The first and second signal strengths are associated with first and second ones of the power levels, respectively. The positioning device obtains the current signal strength and the associated current power level at the current position, calculates a third signal strength for each training point according to the first, second and current power levels and the first and second signal strengths, and compares the current and third signal strengths according to the indoor environment to estimate the current position.

Description

Indoor positioning method, indoor positioning system and computer readable medium

technical field

The present invention relates to indoor positioning, in particular to a method and system for providing fingerprint-based positioning services when signal source power is variable.

Background technique

Fingerprint indoor positioning, taking the application of wireless local area network (wireless local area network or Wi-Fi) as an example, after deploying multiple base stations (access points) in an indoor environment, first of all, multiple coordinates in this indoor environment are required Measure the signal strength (received signalstrength) from each base station to build a "radio map" (radio map). Then, when the user enters the indoor environment and wants to know when he is located, he can perform pattern matching with the radio frequency map according to the received signal strength of each base station. The coordinates of those who receive the same or close ones are their locations.

In the operation process of WLAN, the transmission power of each base station often has independent dynamic modulation, no matter it is manually done by the administrator or an automatic mechanism as defined in the IEEE 802.11h standard. Since the modulated power is different from the power used when measuring the radio frequency map, it is obvious that there will be serious mismatch and positioning error when comparing the characteristics of the received signal strength with the radio frequency map. The intuitive solution is to measure the signal strength of all base stations and all possible transmission powers to build a huge radio frequency map, but in a slightly larger building, this will consume a lot of manpower and man-hours, and it is not practical OK.

Contents of the invention

In view of the above problems, the present invention aims to provide an indoor positioning method and system, which can reflect the current power of the positioning signal source by means of a controllable number of measurement adaptive (adapt) radio frequency maps, and reduce the mismatch and positioning error of the fingerprinting method.

The indoor positioning method provided by the present invention is used to provide positioning services for an indoor environment. The indoor environment has multiple training points and is provided with at least one signal source, and the signal source has multiple power levels. The indoor positioning method includes: obtaining the current signal strength in a first period, which is a wireless signal received and transmitted from the aforementioned signal source based on a certain current position of the aforementioned indoor environment; obtaining the signal at the aforementioned power level from the first the current power level according to which the wireless signal is transmitted during the period; obtaining the first signal strength of each of the aforementioned training points, which is associated with the first power level of the aforementioned power levels; obtaining the second signal strength of at least one adaptation point among the aforementioned training points , which is associated with the second power level in the aforementioned power levels; according to the first power level, the second power level, the current power level, the first signal strength and the second signal strength, a third signal strength is calculated for each training point; And comparing the current signal strength with the third signal strength, and estimating the aforementioned current position according to the indoor environment.

The invention provides a computer-readable medium having a computer program for causing a processor to execute a plurality of instructions for processing positioning requirements for an indoor environment having a plurality of training points and having at least A signal source with multiple power levels. The aforementioned instructions include: acquiring the current signal strength, which is based on a wireless signal received and transmitted from the aforementioned signal source at a certain current location in the aforementioned indoor environment; acquiring the current power level of the aforementioned power level by which the signal source transmits the wireless signal; obtaining a first signal strength of each of the aforementioned training points associated with a first power level of the aforementioned power levels; obtaining a second signal strength of at least one adaptation point of the aforementioned training points associated with a second of the aforementioned power levels power level; according to the first power level, the second power level, the current power level, the first signal strength and the second signal strength, calculate the third signal strength for each training point; and compare the current signal strength and the third signal strength , and estimate the aforementioned current location according to the indoor environment.

The indoor positioning system provided by the present invention is used to provide positioning service for an indoor environment, and the indoor environment has multiple training points. The indoor positioning system includes at least one signal source, a storage device and a positioning device. The signal source is set in the aforementioned indoor environment and has multiple power levels for transmitting wireless signals according to one of the power levels. The storage device is used to store the first signal strength for each training point and store the second signal strength for at least one adjustment point in the training point; the first signal strength is associated with the first power level in the aforementioned power levels, and the second signal strength is associated with The second power level in the preceding power levels. The positioning device is coupled to the storage device, and is used to obtain the current signal strength, which is based on the wireless signal received and transmitted from the aforementioned signal source at a certain current location of the aforementioned indoor environment, and is used to obtain the aforementioned power level based on which the signal source transmits The current power level of the wireless signal is used to calculate the third signal strength for each training point according to the first power level, the second power level, the current power level, the first signal strength and the second signal strength, and to compare The current signal strength and the third signal strength are used to estimate the aforementioned current location according to the indoor environment.

In summary, the indoor positioning method, indoor positioning system and computer-readable media provided by the present invention use a linear relationship between power levels, and the complete radio frequency map under the first power level and the second power level are lower than a few training points. (Adjustment point) The received signal strength can dynamically generate a radio frequency map at any current power level. When there are multiple signal sources in the indoor environment, more features on the radio frequency map can be compared with the current signal strength, increasing the accuracy of estimating the current location.

Description of drawings

FIG. 1 is a high-level block diagram of an embodiment of an indoor positioning system according to the present invention.

FIG. 2 is an illustration of a signal source installed in an indoor environment.

Fig. 3 is a flowchart of an offline stage in an embodiment of an indoor positioning method of the present invention.

Fig. 4 is a flowchart of an online phase in an embodiment of an indoor positioning method of the present invention.

[Description of Reference Signs]

1 Indoor Positioning System

11, 11a, 11b, 11c signal source

13 Management device

15 positioning device

17 storage device

2 Indoor environment

21-26 training points

Detailed ways

The detailed features and advantages of the present invention are described in detail below in the implementation mode, the content is enough to make any person familiar with the related art understand the technical content of the present invention and implement it accordingly, and according to the content disclosed in this specification, the scope of the patent application and the drawings , anyone skilled in the art can easily understand the purpose and advantages of the present invention. The following examples are to further describe aspects of the present invention in detail, but not to limit the scope of the present invention in any way.

See Figure 1. FIG. 1 is a high-level block diagram of an embodiment of an indoor positioning system according to the present invention. In this embodiment, the indoor positioning system 1 is used to provide positioning services for indoor environments, and includes at least one signal source 11 , a management device 13 , a positioning device 15 and a storage device 17 . The indoor environment has multiple training points. The signal source 11 is set in an indoor environment, coupled to the storage device 17 , has multiple power levels, and transmits wireless signals according to one of the multiple power levels. The signal source 11 may be a component of a wireless local loop, such as a base station or a gateway of a wireless local area network or a Worldwide Interoperability for Microwave Access (WiMAX), or may belong to a A wireless sensor network (wireless sensor network), such as a sensor that conforms to standards such as ZigBee or ISA100.11a. The management device 13 is not a necessary component of the indoor positioning system 1 . In one embodiment, the signal source 11 is controlled by the management device 13, including the latter determining the power level at which the former transmits the wireless signal. Formally speaking, the management device 13 sets the signal source 11 such that the signal source 11 transmits wireless signals according to one of the multiple power levels. In other embodiments, the signal source 11 can self-detect and adjust according to the network status. The positioning device 15 processes the positioning requirements of the indoor environment where the signal source 11 is located, and selectively generates or provides the aforementioned adjusted radio frequency map (including the third signal strength, see below). Depending on whether the management device 13 exists or not, the positioning device 15 can directly inquire the signal source 11 of the currently used power level through the management device 13, or the management device 13 can provide this information to the positioning device 15. The storage device 17 is used for storing the first signal strength for each training point, and for storing the second signal strength for at least one adjustment point in these training points, the first signal strength is associated with the first power level in the plurality of power levels , the second signal strength is associated with a second power level of the plurality of power levels. In other words, the storage device 17 is used to store the complete radio frequency map (including the first signal strength) under the first power level, and the adaptation data (including the second signal strength) acquired at a few locations in the indoor environment under the second power level . The management device 13 , the positioning device 15 and the storage device 17 do not have a certain geographical relationship with the indoor environment, unlike the signal source 11 which must be set in the indoor environment. These three can be specialized equipment, and can also partially operate on general-purpose servers or computers.

The positioning device 15 is coupled to the storage device. The positioning device 15 obtains the current signal strength, which is based on the current wireless signal received and transmitted from the signal source 11 at the current location of the indoor environment. And the positioning device 15 obtains the current power level according to which the signal source 11 transmits the current wireless signal among the multiple power levels. The positioning device 15 calculates a third signal strength for each training point according to the first power level, the second power level, the current power level, the first signal strength and the second signal strength. And the positioning device 15 compares the current signal strength with the third signal strength, and estimates the current position according to the indoor environment. In this embodiment, the positioning device 15 obtains the current power level from or through the management device 13 .

See Figure 2. FIG. 2 is an illustration of a signal source installed in an indoor environment. In this embodiment, training points 21 to 26 are distributed in the indoor environment 2, and a plurality of signal sources 11a to 11c are provided. At the same time training points 23 and 25 were selected as adaptation points. Each signal source 11a, 11b or 11c transmits its own wireless signal. For example, if a wireless signal from the signal source 11b is received at the training point 21, the signal strength of the wireless signal is recorded for the training point 21; if no wireless signal from the signal source 11a is received at the training point 26, The intensity of the signal source 11a can then be recorded for the training point 26 as zero. As mentioned earlier, RFMap records the signal strength at each training point for each source in the indoor environment. The indoor environment 2 is set with six training points 21 to 26 and three signal sources 11a to 11c, so there should be 18 values in the entire radio frequency map. Since the signal sources 11a to 11c are independent of each other in the adjustment calculation of the present invention, for the sake of brevity, the following only takes the signal source 11a as an example to illustrate the technical content of the present invention, and those with ordinary knowledge in the field of the present invention should be able to easily deduce And how to complete indoor positioning under multiple signal sources. In addition, the signal source 11a can transmit wireless signals according to multiple power levels, so that the received strengths are different. For example, the signal source 11a can have seven power levels from 1 to 7, and two adjacent power levels correspond to a power difference of 3 decibel milliwatts (dBm). For example, power level 1 represents -1dBm, and power level 2 represents 2dBm, to power level 7 represents 17dBm, equivalent to a transmit power of 0.78 milliwatts (mW) to 50 mW.

Please match Figure 1 and Figure 2, and refer to Figure 3. Fig. 3 is a flowchart of an offline stage in an embodiment of an indoor positioning method of the present invention. Step S301 receives wireless signals at the plurality of training points during the second period, so as to record the first signal strength for each of the training points. The wireless signals are transmitted from the second period according to the first power level, and the second period earlier than the first period (see below). Step S303 is to set the signal source in the third time period, so that the signal originates from the third time period to transmit the wireless signal according to the second power level, and the third time period is later than the second time period and earlier than the first time period. Step S305 is to receive a wireless signal at at least one adjustment point during a third time period, so as to record a second signal strength for the adjustment point. The second period is distinguished from the third period and the first period to indicate the time relationship of the above steps.

The offline phase is the steps required to build a radio map and adapt the data. As shown in FIG. 3 , first in step S301 , all training points 21 to 26 receive wireless signals transmitted by the signal source 11 a at a first power level. The first power level may be a default value of the signal source 11a, or a value commonly used or currently used by the indoor environment 2 set manually or by the management device 13 . For all training points 21 to 26 the first signal strengths recorded at their locations can form a radio frequency map at the first power level. Next, in step S303, the signal source 11a is set to transmit wireless signals according to the second power level. Finally, in step S305, wireless signals are received again at the training points (adaptation points) 23 and 25 to record the second signal strength, which is used to adapt the radio frequency map based on the first signal strength to generate adaptation data. Both the radio frequency map and the adaptation data mentioned above can be stored by the storage device 17 . Please note that the present invention does not limit how to select the number and specific locations of the adaptation points; some selection methods may be better than others in the accuracy of subsequent positioning. Importantly, the freedom to choose the adaptation point makes the present invention applicable to indoor environments of various scales, making fingerprint positioning spatially scalable.

Please cooperate with Figure 1 and Figure 2, and refer to Figure 4. Fig. 4 is a flowchart of an online phase in an embodiment of an indoor positioning method of the present invention. The online phase is a number of steps to generate an adapted RF map in response to a positioning requirement. When a mobile device (such as a mobile phone, a tablet computer or a notebook computer) entering the indoor environment 2 may wish to know its current position in the indoor environment 2 and send a positioning request, the positioning request is received and processed by the positioning device 15, and the positioning device 15 In step S401, obtain the current signal strength received by the mobile device from the signal source 11a at the current location (in the first period, the first period is later than the second period and the third period of the offline phase). In step S403, the positioning device 15 obtains the current power level among the plurality of power levels by which the signal source 11a currently transmits wireless signals from the management device 13 or the signal source 11a itself. In step S405, the positioning device 15 obtains the first signal strength of each training point. The first signal strength is associated with a first power level of the plurality of power levels. In other words, in step S405 , the positioning device 15 obtains the radio frequency map based on the first power level from the storage device 17 . In step S407, the positioning device 15 judges whether the current power level obtained through the query in step S403 is the same as the first power level; if they are the same, the basic radio frequency map including the first signal strength is directly compared with the current signal strength in step S408 Yes, and the positioning device 15 estimates the current location according to the indoor environment 2, such as an indoor map. If not, step S409 is executed to obtain the adaptation data including the second signal strength from the storage device 17 . The second signal strength is associated with the second power level and the adaptation points 23 and 25 of the training points 21-26. In step S411, the positioning device 15 is based on the first power level, the second power level, the current power level, the first signal strength and the second signal strength, or in other words, based on the basic radio frequency map, the adaptation data and the current power level , calculate the adjusted radio frequency map (including the third signal strength of the training points 21 to 26) for step S413. In step S413 , the positioning device 15 compares the current signal strength with the third signal strength, and estimates the current position according to the indoor environment 2 .

Since the power levels of the signal sources 11a to 11c are limited, different "third power levels" can be assumed in the offline phase to automatically generate signal strengths for all power levels for all training points 21 to 26, and the positioning device 15 is then According to the current power level, the corresponding value is used to generate the radio frequency map.

The adjusted radio frequency map includes the third signal strengths of the training points 21 to 26, and simulates the values that can be measured at the training points 21 to 26 respectively if the wireless signal is transmitted at the current power level in the offline phase. In one embodiment, the third signal strength is the first signal strength plus an adaptation term. In yet another embodiment, this adaptation item can be expressed as:

$<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; o</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span>\frac{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; ,</span>$

Where w is a weight between 0 and 1, s is the power difference corresponding to two adjacent power levels in the power level, l ₃ is the current power level, l ₁ is the first power level, a ₂ is the second signal strength , o ₁ is the first signal strength, l ₂ is the second power level. Taking the specification example of the aforementioned signal source 11a as an example, assuming that the first power level is 1, the second power level is 7, and the current power level is 6, then s=3dBm, l ₃ =6, l ₁ =1, l ₂ = 7. The units of a ₂ and o ₁ can also be converted into dBm. From the above expression, it can be found that the adjustment item includes the theoretical value (related to s) and the measured value (related to a ₂ , o ₁ ), and the two are added in a ratio determined by .

When there are multiple adjustment points, calculating the third signal strength for each training point is based on the second signal strength of one of the adjustment points closest to the training point. In an embodiment, the weight w is set according to the distance between the adjustment point and the training point, or the variation of the second signal strength over time.

More specifically, when calculating the third signal strength for a certain training point, it is first necessary to select the second signal strength of the most suitable adjustment point. Generally speaking, the so-called most suitable refers to the shortest distance; if the training point itself is the adjustment point, it is obvious that the second signal strength of itself is the most suitable. According to the distance relationship between the training point and the most suitable adjustment point, simple optimization can be used to solve the weight w in the offline stage or the online stage. In the optimization process, the objective function may be the average positioning error after cross-validation. If the weights are calculated in the offline stage, gradient descent, Newton's method, or even heuristic search can be used to gradually approximate to find the optimal solution. The weight can also be any reasonable value between 0 and 1. When w is large, it means that more trust is given to the actual measured second signal strength during adjustment; this may simply mean that the distance between the training point and the selected adjustment point is relatively close, or it may mean that there are unpredictable factors in the indoor environment that make the difference There is no linear relationship between the signal strength at the power level. When w is small, in addition to the reasons contrary to the above, it may also indicate that the second signal strength is not stable when measured in the offline stage, and should not be overly trusted. For example, in the indoor environment 2 , the training point 23 may be the coordinated adaptation point of the training points 22 and 24 . If the third signal strength of the training point 24 is calculated as 0.6, then w may be 0.4 for the training point 22, reflecting its relatively long distance from the adjustment point.

The present invention also provides a computer readable medium having computer program code for causing a processor to execute instructions for processing positioning requirements for an indoor environment. The indoor environment has multiple training points and is provided with at least one signal source. This source has several power levels. The aforementioned instructions include: obtaining the current signal strength, which is based on the wireless signal received and transmitted from the aforementioned signal source at a certain current location of the aforementioned indoor environment; obtaining the current power level of the aforementioned signal source according to which the signal source transmits the wireless signal; obtaining the aforementioned a first signal strength of each of the training points, which is associated with a first power level of the aforementioned power levels; obtaining a second signal strength of at least one adaptation point of the aforementioned training points, which is associated with a second power level of the aforementioned power levels ; According to the first power level, the second power level, the current power level, the first signal strength and the second signal strength, calculate the third signal strength for each training point; and compare the current signal strength and the third signal strength, and The aforementioned current location is estimated according to the indoor environment.

In an embodiment, after obtaining the first signal strength of each training point, the instructions further include determining whether the current power level is the same as the first power level. Wherein, when the current power level is different from the first power level, the second signal strength of at least one adjustment point is obtained. Wherein when the current power level is the same as the first power level, compare the current signal strength with the first signal strength.

In one embodiment, the third signal strength is the first signal strength plus an adaptation term. In an embodiment, this adaptation item can be expressed as:

$<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; o</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\frac{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; ,</span>$

Where w is a weight between 0 and 1, s is the power difference corresponding to two adjacent power levels in the power level, l ₃ is the current power level, l ₁ is the first power level, a ₂ is the second signal strength , o ₁ is the first signal strength, o ₁ is the second power level.

When there are multiple adjustment points, calculating the third signal strength for each training point is based on the second signal strength of one of the plurality of adjustment points closest to the training point. In an embodiment, the weight w is set according to the distance between the adjustment point and the training point, or the variation of the second signal strength over time.

To sum up, the indoor positioning system provided by the present invention includes a signal source, a positioning device, a storage device and an optional management device, and the indoor positioning method can be divided into an offline stage and an online stage. Taking the complete radio frequency map under the first power level and the received signal strength at a few training points under the second power level, the main steps of adjusting the radio frequency map can be performed in the offline stage or the online stage by using the linear relationship between the power levels. Reflecting the current power of the signal source used for positioning is sufficient to achieve the purpose of reducing the mismatch and positioning error of the fingerprint method. In terms of adjustment details, the third signal strength is calculated from the first signal strength for the training points one by one. The calculation process considers the distance relationship between the training point and the adjustment point, the stability of the second signal strength at the adjustment point, and the overall effect on the second signal strength. Strength of trust.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (19)

1. An indoor positioning method for providing positioning services to an indoor environment, the indoor environment has a plurality of training points and is provided with at least one signal source, the signal source has multiple power levels, it is characterized in that the indoor positioning Methods include: Obtaining a current signal strength during a first time period, the current signal strength is based on a wireless signal transmitted from the signal source received at a current location of the indoor environment; Obtaining a current power level at which the wireless signal is transmitted from among the plurality of power levels at which the signal originates from the first time period; obtaining a first signal strength of each of the training points, the first signal strength being associated with a first power level in the plurality of power levels; obtaining a second signal strength of at least one adaptation point among the plurality of training points, the second signal strength being associated with a second power level among the plurality of power levels; calculating a third signal strength for each training point according to the first power level, the second power level, the current power level, the first signal strength and the second signal strength; and Comparing the current signal strength with the third signal strength, and estimating the current location according to the indoor environment. 2. The indoor positioning method according to claim 1, wherein the third signal strength is the first signal strength plus an adjustment term. 3. The indoor positioning method according to claim 2, wherein the adaptation item is obtained according to an expression, and the expression is: $<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; o</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\frac{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; ;</span>$ Wherein, w is a weight, the weight is between 0 and 1, s is the power difference corresponding to two adjacent power levels among the plurality of power levels, l ₃ is the current power level, l ₁ is the first power level, a ₂ is the second signal strength, o ₁ is the first signal strength, l ₂ is the second power level. 4. The indoor positioning method according to claim 3, wherein when there are a plurality of adjustment points, calculating the third signal strength for each training point is based on one of the plurality of adjustment points closest to the training point The second signal strength of one. 5. The indoor positioning method as claimed in claim 4, wherein the weight is set according to the distance between the adjustment point and the training point, or a variation of the second signal strength over time. 6. The indoor positioning method according to claim 1, further comprising: after the step of obtaining the first signal strength of each training point: judging whether the current signal level is the same as the first power level; wherein when the current signal level is different from the first power level, obtaining the second signal strength of at least one of the adaptation points; Wherein when the current signal level is the same as the first power level, the current signal strength is compared with the first signal strength, and the current position is estimated according to the indoor environment. 7. The indoor positioning method according to claim 1, further comprising: receiving the wireless signal at the plurality of training points during a second time period to record the first signal strength for each of the training points, the wireless signal being the signal originating from the second time period according to the first power level transmitting, the second time period is earlier than the first time period; setting the signal source in a third time period so that the signal originates from the third time period to transmit the wireless signal according to the second power level, the third time period is later than the second time period and earlier than the first time period; and The wireless signal is received at at least one of the adjustment points during the third time period to record the second signal strength for the adjustment point. 8. A computer readable medium having a computer program for causing a processor to execute instructions for processing positioning requirements for an indoor environment having a plurality of training points and At least one signal source is provided, the signal source has multiple power levels, and the multiple instructions include: obtaining a current signal strength, the current signal strength being a wireless signal received and transmitted from the signal source based on a current location of the indoor environment; obtaining a current power level at which the signal source transmits the wireless signal among the plurality of power levels; obtaining a first signal strength of each of the training points, the first signal strength being associated with a first power level in the plurality of power levels; obtaining a second signal strength of at least one adaptation point among the plurality of training points, the second signal strength being associated with a second power level among the plurality of power levels; calculating a third signal strength for each training point according to the first power level, the second power level, the current power level, the first signal strength and the second signal strength; and Comparing the current signal strength with the third signal strength, and estimating the current location according to the indoor environment. 9. The computer-readable medium of claim 8, wherein the third signal strength is the first signal strength plus an adjustment term. 10. The computer-readable medium according to claim 9, wherein the adaptation item is obtained according to an expression, the expression is: $<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; o</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\frac{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; ;</span>$ Wherein, w is a weight, the weight is between 0 and 1, s is the power difference corresponding to two adjacent power levels among the plurality of power levels, l ₃ is the current power level, l ₁ is the first power level, a ₂ is the second signal strength, o ₁ is the first signal strength, l ₂ is the second power level. 11. The computer-readable medium of claim 10, wherein when there are a plurality of adjustment points, calculating the third signal strength for each training point is based on the plurality of adjustment points closest to the training point One of the second signal strengths. 12. The computer-readable medium of claim 11, wherein the weight is set according to a distance between the adaptation point and the training point, or a variation of the second signal strength over time. 13. The computer-readable medium of claim 8, wherein after obtaining the first signal strength of each training point, the plurality of instructions further comprise: judging whether the current power level is the same as the first power level; wherein when the current power level is different from the first power level, obtaining the second signal strength of at least one of the adaptation points; Wherein when the current power level is the same as the first power level, the current signal strength is compared with the first signal strength, and the current position is estimated according to the indoor environment. 14. An indoor positioning system for providing positioning services to an indoor environment, the indoor environment has multiple training points, the indoor positioning system comprising: at least one signal source, disposed in the indoor environment, has a plurality of power levels, and is used to transmit a wireless signal according to one of the plurality of power levels; a storage device for storing a first signal strength for each of the training points, and for storing a second signal strength for at least one adaptation point in the plurality of training points, the first signal strength is associated with the plurality of training points a first power level of the power levels, the second signal strength associated with a second power level of the plurality of power levels; and a positioning device coupled to the storage device; Wherein the positioning device obtains a current signal strength, the current signal strength is a current wireless signal received and transmitted from the signal source based on a current position of the indoor environment; Wherein the positioning device obtains a current power level according to which the signal source transmits the current wireless signal among the plurality of power levels; Wherein the positioning device calculates a third signal strength for each training point according to the first power level, the second power level, the current power level, the first signal strength and the second signal strength; Wherein the positioning device compares the current signal strength with the third signal strength, and estimates the current position according to the indoor environment. 15. The indoor positioning system of claim 14, wherein the third signal strength is the first signal strength plus an adjustment term. 16. The indoor positioning system according to claim 15, wherein the positioning device obtains the adaptation item according to an expression, the expression is: $<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; o</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span>\frac{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; ;</span>$ Wherein, w is a weight, the weight is between 0 and 1, s is the power difference corresponding to two adjacent power levels among the plurality of power levels, l ₃ is the current power level, l ₁ is the first power level, a ₂ is the second signal strength, o ₁ is the first signal strength, l ₂ is the second power level. 17. The indoor positioning system according to claim 16, wherein when there are a plurality of adjustment points, the positioning device calculates the third signal strength for each training point based on the plurality of adjustment points closest to the training point Click on one of them for this second signal strength. 18. The indoor positioning system as claimed in claim 17, wherein the positioning device sets the weight according to the distance between the adjustment points and the training points or a variation of the second signal strength over time . 19. The indoor positioning system as claimed in claim 14, further comprising: a management device for setting the signal source so that the signal source transmits the wireless signal according to one of the multiple power levels; Wherein the positioning device obtains the current power level from or through the management device.