WO2023032277A1

WO2023032277A1 - Position measurement device, position measurement method, and program

Info

Publication number: WO2023032277A1
Application number: PCT/JP2022/009867
Authority: WO
Inventors: 真登北; 裕之鎌田; ダニエルマーセルシュナイダー
Original assignee: ソニーグループ株式会社
Priority date: 2021-09-01
Filing date: 2022-03-08
Publication date: 2023-03-09
Also published as: JPWO2023032277A1

Abstract

The present disclosure relates to a position measurement device, a position measurement method, and a program which make it possible to further improve position measurement accuracy. A distance measurement value calculation unit calculates, on the basis of communications for distance measurement that are performed between a communication terminal and a plurality of communication devices, a distance measurement value which indicates the distance between the communication terminal and each of the plurality of communication devices. A reliability calculation unit calculates the reliability of the distance measurement value. A weight control unit performs weight control for changing, in accordance with the reliability, a weight with respect to a first measurement position that is obtained from the distance measurement value. A position measurement calculation unit uses the first measurement position that has been weighted in accordance with the weight control and a second measurement position that is obtained by use of another position measurement technique to perform position measurement calculation for obtaining a third measurement position which is output as a result of measuring the position of the communication terminal. This technique can be applied to, for example, a distance measurement system that uses UWB.

Description

Positioning device, positioning method, and program

The present disclosure relates to a positioning device, a positioning method, and a program, and more particularly to a positioning device, a positioning method, and a program that can further improve positioning accuracy.

Conventionally, development of a positioning system that measures the user's position using distance measurement communication according to the UWB (Ultra Wide Band) standard has progressed, and various technologies have been developed to improve positioning accuracy. Proposed.

For example, Patent Document 1 discloses a technique for estimating a position based on a distance to a peripheral device selected based on total accuracy calculated by position accuracy, which is the accuracy of the position, and distance accuracy, which is the accuracy of the distance. Proposed.

WO2020/003353

By the way, the above-mentioned Patent Document 1 states that the smaller the value of the position accuracy and the distance accuracy, the higher the positioning accuracy. It is considered insufficient to determine if the given position is correct.

The present disclosure has been made in view of such circumstances, and aims to further improve positioning accuracy.

A positioning device according to one aspect of the present disclosure measures distances between each of a plurality of communication devices and the communication terminal based on communication for ranging performed between the plurality of communication devices and the communication terminal. a distance value calculation unit that calculates a distance value; a reliability calculation unit that calculates reliability of the distance measurement value; A weight control unit that performs variable weight control, the first positioning position weighted according to the weight control, and a positioning technique other than the positioning technique using communication for range finding. a positioning calculation unit that performs positioning calculation to determine a third positioned position to be output as a positioning result of the position of the communication terminal, using the second positioned position;

A positioning method or program according to one aspect of the present disclosure determines the distance between each of the plurality of communication devices and the communication terminal based on communication for ranging performed between the plurality of communication devices and the communication terminal. Calculating a measured distance value indicating the distance measured value, calculating a reliability of the measured distance value, and weight control for changing a weight for a first positioning position obtained from the measured distance value according to the reliability. and the first positioning position weighted according to the weight control, and the second positioning position obtained using a positioning technique other than the positioning technique using communication for ranging. and performing positioning calculation for obtaining a third positioned position to be output as a positioning result of the position of the communication terminal.

In one aspect of the present disclosure, a distance measurement value indicating a distance between each of a plurality of communication devices and a communication terminal is calculated based on distance measurement communication performed between the plurality of communication devices and the communication terminal. Then, the reliability of the measured distance value is calculated, weight control is performed to change the weight of the first measured position obtained from the measured distance value according to the reliability, and the first measured position is weighted according to the weight control. A third positioning position output as a positioning result of the position of the communication terminal using the position and a second positioning position obtained using a positioning technology other than the positioning technology using communication for ranging is performed.

1 is a diagram illustrating a configuration example of an embodiment of a positioning system to which the present technology is applied; FIG. It is a figure explaining a direct wave and a reflected wave. 1 is a block diagram showing a configuration example of a mobile terminal; FIG. It is a figure explaining a received signal profile. 6 is a flowchart for explaining positioning processing using a received signal profile; FIG. 11 is a flowchart for explaining positioning processing using dispersion of measured distance values; FIG. FIG. 10 is a flowchart for explaining positioning processing using a communication success rate; FIG. FIG. 10 is a flowchart for explaining positioning processing using an error correction rate; FIG. 1 is a block diagram showing a configuration example of an embodiment of a computer to which the present technology is applied; FIG.

Specific embodiments to which the present technology is applied will be described in detail below with reference to the drawings.

<Configuration example of positioning system>
FIG. 1 is a diagram showing a configuration example of an embodiment of a positioning system to which the present technology is applied.

The positioning system 11 shown in FIG. 1 is configured by connecting UWB anchors 12-1 to 12-4 and a ranging server 13, and is capable of positioning the position of a user possessing a mobile terminal 14.

In FIG. 1, for example, in a room such as an office where UWB anchors 12-1 to 12-4 are installed, positioning in a use case in which enrollment management is performed using location information of a user possessing a mobile terminal 14 is shown. An example use of system 11 is shown. In addition to these use cases, the positioning system 11 can also be used for analyzing customer behavior, presenting real-time advertisements or product information, in-store customer navigation, employee behavior visualization and business improvement, PDCA (Plan-Do- Check-Action) It is expected to be used in use cases such as streamlining the cycle.

Under the control of the ranging server 13, the UWB anchors 12-1 to 12-4 carry out distance measurement communication (hereinafter referred to as UWB distance measurement communication) with the mobile terminal 14 according to the UWB standard.

The ranging server 13 performs various controls necessary for the UWB anchors 12-1 to 12-4 to perform UWB ranging communication. For example, the ranging server 13 controls the timing at which each of the UWB anchors 12-1 to 12-4 communicates with the mobile terminal 14 in UWB ranging communication.

The mobile terminal 14 performs UWB ranging communication with the UWB anchors 12-1 through 12-4 to obtain ranging values indicating the distances from the UWB anchors 12-1 through 12-4, respectively. Positioning processing for positioning the position of the mobile terminal 14 can be performed from the measured distance values. Hereinafter, the current position of the mobile terminal 14 obtained by calculation based on UWB ranging communication will be referred to as a UWB positioning position.

For example, in the positioning system 11, in UWB ranging communication, transmission and reception of commands and responses for ranging are performed between the UWB anchor 12 and the mobile terminal 14 by electromagnetic waves. Then, the distance measurement value between the UWB anchor 12 and the mobile terminal 14 can be obtained based on the transmission timing and reception timing of the ranging command and the transmission timing and reception timing of the ranging response. Then, when the distance measurement values between at least three or more UWB anchors 12 are obtained, the intersection of circles centered on each UWB anchor 12 and having the distance measurement values as radii is taken as the UWB positioning position of the mobile terminal 14. can be calculated.

At this time, as shown in FIG. 2, the mobile terminal 14 may directly receive the electromagnetic wave output from the UWB anchor 12, or may receive the electromagnetic wave output from the UWB anchor 12 and reflected by metal or the like. Sometimes. Due to the occurrence of such a phenomenon, the received signal of the mobile terminal 14 conflicts, and as a result, it is assumed that it may become difficult to stably obtain the distance measurement value using UWB. A similar phenomenon may also occur when the UWB anchor 12 receives electromagnetic waves output from the mobile terminal 14 . Furthermore, it is assumed that the UWB anchor 12 or the mobile terminal 14 cannot normally receive direct electromagnetic waves due to the influence of radio wave absorption by the human body.

Therefore, the positioning system 11 is configured so as to be able to determine the measured position based on positioning processing using various positioning technologies in addition to the positioning technology using UWB. Then, in the positioning system 11, by controlling the weight for the positioning position obtained based on those positioning technologies, according to the reliability of the distance measurement value using UWB, the positioning result of the position of the mobile terminal 14 is It is possible to improve the positioning accuracy of the positioning position that is finally obtained.

FIG. 3 is a block diagram showing a configuration example of the mobile terminal 14. As shown in FIG.

As shown in FIG. 3, the mobile terminal 14 includes a geomagnetic sensor 21, an acceleration sensor 22, a gyro 23, a UWB communication unit 24, a PDR processing unit 25, a UWB distance measurement value calculation unit 26, a reliability calculation unit 27, a weight control unit 28 and a positioning calculator 29 .

The geomagnetic sensor 21 detects the geomagnetism at the current position of the mobile terminal 14 and supplies it to the positioning calculator 29 . The acceleration sensor 22 detects the acceleration of the mobile terminal 14 and supplies it to the PDR processing section 25 , and the gyro 23 detects the angular velocity of the mobile terminal 14 and supplies it to the PDR processing section 25 .

The UWB communication unit 24 can communicate according to the UWB standard. For example, the UWB communication unit 24 performs UWB ranging communication to transmit and receive ranging commands and responses to and from each of the UWB anchors 12-1 to 12-4. Then, the UWB communication unit 24 acquires the transmission timing and reception timing of each distance measurement command and the transmission timing and reception timing of each distance measurement response, and sends them to the UWB distance measurement value calculation unit 26 supply.

The PDR processing unit 25 uses the acceleration of the mobile terminal 14 supplied from the acceleration sensor 22 and the angular velocity of the mobile terminal 14 supplied from the gyro 23 to perform PDR (Pedestrian Dead Reckoning) processing so that the mobile terminal 14 current positions can be obtained. Then, the PDR processing unit 25 supplies the current position of the mobile terminal 14 obtained by the PDR processing (hereinafter referred to as PDR positioning position) to the positioning calculation unit 29 .

Based on the transmission timing and reception timing of the command for ranging supplied from the UWB communication unit 24 and the transmission timing and reception timing of the response for ranging, the UWB distance measurement value calculation unit 26 calculates the UWB anchor 12- 1 to 12-4 are calculated and supplied to the positioning calculation unit 29 .

The reliability calculation unit 27 calculates the reliability of the distance measurement value calculated by the UWB distance measurement value calculation unit 26 and supplies it to the weight control unit 28 . For example, as will be described later, the reliability calculation unit 27 can calculate the received signal profile, the dispersion of the measured distance value, the communication success rate, or the error correction rate as the reliability of the measured distance value using UWB. .

The weight control unit 28 performs weight control to change the weight for the UWB positioning position used when the positioning calculation unit 29 performs positioning calculation, according to the reliability supplied from the reliability calculation unit 27 . For example, the weight control unit 28 performs weight control so as to increase the weight for the UWB positioning position if the reliability of the distance measurement value using UWB is high, and if the reliability of the distance measurement value using UWB is low , weight control is performed so as to reduce the weight for the UWB positioning position.

The positioning calculation unit 29 obtains the UWB positioning position based on the UWB distance measurement values with each of the UWB anchors 12-1 to 12-4 supplied from the UWB distance measurement value calculation unit 26. The positioning calculation unit 29 also refers to a geomagnetic map acquired in advance to obtain the current position of the mobile terminal 14 according to the geomagnetism supplied from the geomagnetic sensor 21 (hereinafter referred to as the geomagnetic positioning position). Then, the positioning calculation unit 29 uses the UWB positioning position weighted according to the weight control by the weight control unit 28, the PDR positioning position, and the geomagnetic positioning position to obtain the current position of the mobile terminal 14 to be output as the positioning result. do the math.

The mobile terminal 14 is configured as described above, and if the reliability of the distance measurement value using UWB is high, the positioning result is such that the contribution rate of the UWB positioning position to the PDR positioning position and the geomagnetic positioning position is high. is obtained. On the other hand, if the reliability of the distance measurement value using UWB is low, a positioning result is obtained in which the contribution rate of the UWB positioning position to the PDR positioning position and the geomagnetic positioning position is low.

In this way, the mobile terminal 14 performs positioning processing in which the weight for the UWB positioning position is controlled based on the reliability of the distance measurement value using UWB, thereby outputting the positioning result of the position of the mobile terminal 14. It is possible to improve the positioning accuracy of the positioning position.

<Processing example of positioning processing in which weight is controlled>
Positioning processing in which weights are controlled based on the reliability of distance measurement values using UWB will be described with reference to FIGS. 4 to 8. FIG.

FIG. 4 is a diagram explaining the received signal profile used as the reliability of the distance measurement value using UWB.

As described above with reference to FIG. 2 , the mobile terminal 14 receives direct waves and reflected waves when performing UWB ranging communication with the UWB anchor 12 . Then, the average power of the received signal (ranging packet) received by the mobile terminal 14 in UWB ranging communication is normally higher for the direct wave and lower for the reflected wave. Also, the mobile terminal 14 receives the direct wave first and the reflected wave later.

Therefore, when the reception condition is good, as shown in A of FIG. 4, the average power of the received signal of the direct wave that is received first is high, and the average power of the received signal of the reflected wave that is received later is low. A received signal profile is generated as follows.

On the other hand, as shown in FIG. 4B, when the average power of the received signal of the direct wave does not have a large difference with respect to the noise level, the reception condition is not good and the UWB communication unit 24 receives the direct wave. It can be judged that there is a high possibility that it has not been possible. Also, as shown in FIG. 4C, when the average power of the received signal of the direct wave is lower than the average power of the received signal of the reflected wave, the reception condition is not good and the UWB communication unit 24 receives the direct wave. It can be judged that there is a high possibility that it has not been possible.

Therefore, the weight control unit 28, according to the reception signal profile generated by the reliability calculation unit 27, when the reception condition of the reception signal in the UWB ranging communication is good, for example, as shown in A of FIG. If it is a received signal profile, it is determined that the reliability of the distance measurement value using UWB is high, and weight control is performed so that the weight for the UWB positioning position is increased. On the other hand, the weight control unit 28, according to the reception signal profile generated by the reliability calculation unit 27, when the reception condition of the reception signal in the UWB ranging communication is not good, for example, B in FIG. 4 or C in FIG. If the received signal profile is as shown in , it is determined that the reliability of the distance measurement value using UWB is low, and weight control is performed so that the weight for the UWB positioning position is reduced.

FIG. 5 is a flow chart explaining the positioning process using the received signal profile as the reliability of the distance measurement value using UWB.

In step S11, the UWB communication unit 24 performs UWB ranging communication with the UWB anchors 12-1 to 12-4. Then, the UWB communication unit 24 acquires the transmission timing and reception timing of the command for ranging and the transmission timing and reception timing of the response for ranging with each of the UWB anchors 12-1 to 12-4. and supplied to the UWB distance measurement value calculation unit 26 . As a result, the UWB distance measurement value calculation unit 26 calculates the UWB anchors 12-1 to 12-4 based on the transmission timing and reception timing of the distance measurement command and the transmission timing and reception timing of the distance measurement response. Calculate the distance measurement between each.

In step S12, the reliability calculation unit 27 acquires from the UWB communication unit 24 the average power of the reception signal received by the UWB communication unit 24 in the UWB ranging communication in step S11. Then, the reliability calculator 27 calculates a received signal profile (see FIG. 4) represented by the average power of the received signal and the reception time as the reliability of the distance measurement value using UWB.

In step S13, the weight control unit 28 performs weight control to change the weight for weighting the UWB positioning position according to the received signal profile calculated by the reliability calculation unit 27 in step S12.

In step S14, the positioning calculation unit 29 obtains the UWB positioning position based on the distance measurement value calculated by the UWB distance measurement value calculation unit 26 in step S11. 28 performs weighting with weight controlled weights. Further, the positioning calculation unit 29 acquires the PDR positioning position obtained by the PDR processing unit 25 and obtains the geomagnetic positioning position according to the geomagnetism supplied from the geomagnetic sensor 21 . Then, the positioning calculation unit 29 uses the weighted UWB positioning position, the PDR positioning position and the geomagnetic positioning position to perform positioning calculation to obtain the current position of the mobile terminal 14 to be output as the positioning result.

As described above, the mobile terminal 14 uses the received signal profile as the reliability of the distance measurement value using UWB, and performs UWB positioning according to whether the reception status of the received signal in UWB distance measurement communication is good. Positioning accuracy can be improved by controlling the weight for the position. For example, when the reception condition of the received signal in UWB ranging communication is not good, the mobile terminal 14 performs weight control so that the weight for the UWB positioning position is reduced, and the contribution rate of the UWB positioning position to the positioning result is reduced. By making it lower, it is possible to avoid a decrease in positioning accuracy.

The reliability calculation unit 27 acquires the reception signal profile from the UWB anchors 12-1 to 12-4 when the UWB anchors 12-1 to 12-4 perform UWB ranging communication with the UWB communication unit 24. may Then, the weight control unit 28 refers not only to the received signal profile of the UWB communication unit 24, but also to the received signal profiles of each of the UWB anchors 12-1 to 12-4, and uses all of them to comprehensively determine the reception status. It can be determined whether it is good or not.

FIG. 6 is a flow chart explaining the positioning process using the variance of the measured distance value as the reliability of the measured distance value using UWB.

In step S21, the UWB communication unit 24 performs UWB ranging communication with the UWB anchors 12-1 to 12-4. Then, the UWB communication unit 24 acquires the transmission timing and reception timing of the command for ranging and the transmission timing and reception timing of the response for ranging with each of the UWB anchors 12-1 to 12-4. and supplied to the UWB distance measurement value calculation unit 26 . As a result, the UWB distance measurement value calculation unit 26 calculates the UWB anchors 12-1 to 12-4 based on the transmission timing and reception timing of the distance measurement command and the transmission timing and reception timing of the distance measurement response. Calculate the distance measurement between each. Then, the reliability calculation unit 27 acquires the distance measurement value calculated by the UWB distance measurement value calculation unit 26 .

In step S22, the reliability calculation unit 27 determines whether or not the distance measurement values have been acquired for a specified number of times. In step S22, when the reliability calculation unit 27 determines that the measured distance values have not been obtained the specified number of times, the process proceeds to step S23.

In step S23, the reliability calculation unit 27 determines whether or not the number of UWB ranging communications in step S21 has exceeded a specified number of communications. In step S23, if the reliability calculation unit 27 determines that the number of UWB ranging communications in step S21 does not exceed the specified number of communications, the process returns to step S21, and the same process is repeated thereafter. .

On the other hand, if it is determined in step S22 that the specified number of distance measurement values have been obtained, or if it is determined in step S23 that the specified number of communications has been exceeded, the process proceeds to step S24. That is, the UWB ranging communication is repeated until the specified number of ranging values are acquired, and even if the specified number of ranging values are not acquired, the UWB ranging communication is repeated until the specified number of communications is reached.

In step S24, the reliability calculation unit 27 calculates the variance of a plurality of distance measurement values obtained by repeated UWB distance measurement communication as the reliability of the distance measurement value using UWB. Also, the UWB distance measurement value calculation unit 26 can obtain an average value of a plurality of distance measurement values and supply the average value to the positioning calculation unit 29 .

In step S25, the weight control unit 28 performs weight control to change the weight for weighting the UWB positioning position according to the dispersion of the distance measurement values calculated by the reliability calculation unit 27 in step S24.

For example, if the variance of the distance measurement values calculated by the reliability calculation unit 27 does not exceed a predetermined threshold, the weight control unit 28 determines that the positioning values using UWB are stably obtained. Weight control is performed so that the weight for the UWB positioning position is increased. On the other hand, if the variance of the distance measurement values calculated by the reliability calculation unit 27 exceeds a predetermined threshold, the weight control unit 28 determines that the positioning values using UWB are not stably obtained. Weight control is performed so that the weight for the UWB positioning position becomes small. Note that the weight control unit 28 may perform weight control by setting a predetermined threshold value, or may perform weight control using, for example, a value corresponding to the dispersion of the measured distance values as a weight.

In step S26, the positioning calculation unit 29 uses the weighted UWB positioning position, the PDR positioning position, and the geomagnetic positioning position as described in step S14 of FIG. Positioning calculation is performed to determine the current position of 14.

As described above, the mobile terminal 14 uses the variance of the measured distance value as the reliability of the measured distance value using UWB, and weights the UWB positioning position according to whether the measured value is stably obtained. By controlling , it is possible to improve the positioning accuracy. For example, when the positioning value is not stably obtained, the mobile terminal 14 performs weight control so that the weight for the UWB positioning position is reduced, thereby reducing the contribution rate of the UWB positioning position to the positioning result. Therefore, it is possible to avoid a decrease in positioning accuracy.

FIG. 7 is a flow chart explaining the positioning process using the communication success rate as the reliability of the distance measurement value using UWB.

In step S31, the UWB communication unit 24 performs UWB ranging communication with the UWB anchors 12-1 to 12-4. Then, when the UWB distance measurement communication is successful, the UWB communication unit 24 transmits and receives commands for distance measurement with each of the UWB anchors 12-1 to 12-4, and responds for distance measurement. The transmission timing and the reception timing are acquired and supplied to the UWB distance measurement value calculation unit 26 . As a result, the UWB distance measurement value calculation unit 26 calculates the UWB anchors 12-1 to 12-4 based on the transmission timing and reception timing of the distance measurement command and the transmission timing and reception timing of the distance measurement response. Calculate the distance measurement between each. Note that, if the UWB ranging communication is not successful, the UWB communication unit 24 can repeatedly attempt the UWB ranging communication.

In step S32, the UWB communication unit 24 determines whether or not the number of successful UWB ranging communications in step S31 has exceeded a specified number of communications. If the UWB communication unit 24 determines in step S32 that the number of successful UWB ranging communications has not exceeded the specified number of communications in step S31, the process returns to step S31, and the same process is repeated thereafter. will be

On the other hand, if the UWB communication unit 24 determines in step S32 that the number of successful UWB ranging communications in step S31 exceeds the specified number of communications, the process proceeds to step S33.

In step S33, the UWB communication unit 24 supplies the reliability calculation unit 27 with the number of attempts of UWB ranging communication and the number of successful UWB ranging communications in step S31. Then, the reliability calculation unit 27 calculates the communication success rate of successful UWB distance measurement communication as the reliability of the distance measurement value using UWB.

In step S34, the weight control unit 28 performs weight control to change the weight for weighting the UWB positioning position according to the communication success rate calculated by the reliability calculation unit 27 in step S33.

For example, if the communication success rate calculated by the reliability calculation unit 27 exceeds a predetermined threshold, the weight control unit 28 can determine that UWB ranging communication is being performed stably. Weight control is performed so that the weight for the positioning position is increased. On the other hand, if the communication success rate calculated by the reliability calculation unit 27 does not exceed a predetermined threshold, the weight control unit 28 can determine that the UWB ranging communication is not stably performed. Weight control is performed so that the weight for the positioning position becomes small. Note that the weight control unit 28 may perform weight control by setting a predetermined threshold value, or may perform weight control using, for example, a value corresponding to the communication success rate as a weight.

In step S35, the positioning calculation unit 29 uses the weighted UWB positioning position, the PDR positioning position, and the geomagnetic positioning position as described in step S14 of FIG. Positioning calculation is performed to determine the current position of 14.

As described above, the mobile terminal 14 uses the communication success rate as the reliability of the distance measurement value using UWB, and weights the UWB positioning position according to whether the UWB distance measurement communication is performed stably. By controlling , it is possible to improve the positioning accuracy. For example, when the UWB ranging communication is not stably performed, the mobile terminal 14 performs weight control so that the weight for the UWB positioning position is reduced, and the contribution rate of the UWB positioning position to the positioning result is reduced. By doing so, it is possible to avoid a decrease in positioning accuracy.

FIG. 8 is a flow chart explaining the positioning process using the error correction rate as the reliability of the distance measurement value using UWB.

In step S41, the UWB communication unit 24 performs UWB ranging communication with the UWB anchors 12-1 to 12-4 with data communication packets added. At this time, the UWB communication unit 24 demodulates the data communication packets transmitted from the UWB anchors 12-1 to 12-4 in the UWB ranging communication, and an error occurs in the data stored in the packets. If so, the error in the data can be corrected by applying an error correction code.

Then, the UWB communication unit 24 acquires the transmission timing and reception timing of the command for ranging and the transmission timing and reception timing of the response for ranging with each of the UWB anchors 12-1 to 12-4. and supplied to the UWB distance measurement value calculation unit 26 . As a result, the UWB distance measurement value calculation unit 26 calculates the UWB anchors 12-1 to 12-4 based on the transmission timing and reception timing of the distance measurement command and the transmission timing and reception timing of the distance measurement response. Calculate the distance measurement between each.

In step S42, the UWB communication unit 24 determines whether or not the number of UWB ranging communications in step S41 has exceeded a specified number of communications. In step S42, when the UWB communication unit 24 determines that the number of UWB ranging communications in step S41 has not exceeded the specified number of communications, the process returns to step S41, and the same process is repeated thereafter.

On the other hand, if the UWB communication unit 24 determines in step S42 that the number of UWB ranging communications in step S41 has exceeded the specified number of communications, the process proceeds to step S43.

In step S43, the UWB communication unit 24 compares the amount of data stored in all data communication packets received in the UWB ranging communication in step S41 and the amount of data in which an error occurred. It is supplied to the reliability calculation unit 27 . Then, the reliability calculation unit 27 calculates the data error correction rate (how much error has occurred in the data stored in the packet for data communication) as the reliability of the distance measurement value using UWB. percentage) is calculated.

In step S44, the weight control unit 28 performs weight control to change the weight for weighting the UWB positioning position according to the error correction rate calculated by the reliability calculation unit 27 in step S43.

For example, if the error correction rate calculated by the reliability calculation unit 27 exceeds a predetermined threshold, the weight control unit 28 can determine that the communication status of UWB ranging communication is not good. Weight control is performed so that the weight for is small. On the other hand, if the error correction rate calculated by the reliability calculation unit 27 does not exceed a predetermined threshold, the weight control unit 28 can determine that the communication status of UWB ranging communication is good, and UWB positioning is performed. Weight control is performed so that the weight for the position is increased. Note that the weight control unit 28 may perform weight control by setting a predetermined threshold value, or, for example, weight control using a value corresponding to the error correction rate as a weight.

In step S45, the positioning calculation unit 29 uses the weighted UWB positioning position, the PDR positioning position, and the geomagnetic positioning position as described in step S14 of FIG. Positioning calculation is performed to determine the current position of 14.

As described above, the mobile terminal 14 uses the error correction rate as the reliability of the distance measurement value using UWB, and weights the UWB positioning position according to whether the UWB distance measurement communication is performed stably. By controlling , it is possible to improve the positioning accuracy. For example, when the communication status of UWB ranging communication is not good, the mobile terminal 14 performs weight control so that the weight of the UWB positioning position is reduced, thereby reducing the contribution of the UWB positioning position to the positioning result. Therefore, it is possible to avoid a decrease in positioning accuracy.

The reliability calculation unit 27 acquires the error correction rate from the UWB anchors 12-1 to 12-4 when the UWB anchors 12-1 to 12-4 perform UWB ranging communication with the UWB communication unit 24. may Then, the weight control unit 28 refers not only to the error correction rate of the UWB communication unit 24, but also to the error correction rate of each of the UWB anchors 12-1 to 12-4, and comprehensively performs UWB ranging using all of them. It can be determined whether or not the communication status of communication is good.

As described above, in the positioning system 11, weight control is performed using the received signal profile, the dispersion of the measured distance value, the communication success rate, or the error correction rate as the reliability of the measured distance value using UWB. It is possible to improve the positioning accuracy of the positioning position and the stability of the positioning. In addition, the received signal profile, the dispersion of the measured distance value, the communication success rate, or the error correction rate may be used individually, or may be used in combination for weight control. In addition to weighting the UWB positioning position, it is also possible to perform weight control such as weighting the PDR positioning position or the geomagnetic positioning position.

Further, in the positioning system 11, for example, if at least three or more of the plurality of distance measurement values have high reliability, that is, three or more highly reliable distance measurement values are determined using UWB. If it can be obtained, weight control may be performed so that the weight for the UWB positioning position is increased. In other words, in this case, it can be determined that the intersection of circles with three highly reliable distance measurement values as radii is sufficiently reliable as the UWB positioning position of the mobile terminal 14. Positioning processing can be performed without using values. Of course, if three or more highly reliable distance measurement values cannot be obtained using UWB, weight control is performed so that the weight for the UWB positioning position is reduced.

Note that this technology can be applied not only to positioning processing using 2-way ranging as described above, but also to positioning processing using, for example, a 1-way ranging method (TDoA: Time Difference of Arrival). can.

For example, in positioning processing using TDoA, the received signal profile, dispersion of ranging values, communication success rate, or error correction rate are used as methods of detecting unreliable ranging values or positioning results. , whether the UWB positioning position of the mobile terminal 14 is within the area surrounded by the UWB anchors 12-1 to 12-4. That is, when the UWB positioning position of the mobile terminal 14 is not within the area surrounded by the UWB anchors 12-1 to 12-4 (outside the area), the reliability of the UWB positioning position may be low. Proven in principle.

Therefore, when the UWB positioning position of the mobile terminal 14 is not within the area surrounded by the UWB anchors 12-1 to 12-4, weight control is performed so that the weight for the UWB positioning position is reduced. Note that the weight control for the UWB positioning position obtained by the positioning processing using TDoA is not performed in the weight control unit 28 as described with reference to FIG. 29 inside. That is, the positioning calculation unit 29 weights the UWB positioning position based on whether the UWB positioning position of the mobile terminal 14 is within the area surrounded by the UWB anchors 12-1 to 12-4, A positioning calculation can be performed to obtain the current position of the mobile terminal 14 to be output as a positioning result.

Further, in the positioning system 11, in addition to performing the above-described positioning processing in the mobile terminal 14, the positioning processing is performed in the ranging server 13 that controls UWB ranging communication by the UWB anchors 12-1 to 12-4. can be In this case, the received signal profile, communication success rate, and error correction rate obtained by the mobile terminal 14 may be supplied from the mobile terminal 14 to the ranging server 13 . Also, the geomagnetism detected by the geomagnetic sensor 21, the acceleration detected by the acceleration sensor 22, and the angular velocity detected by the gyro 23 are supplied from the mobile terminal 14 to the ranging server 13, and the ranging server 13 performs positioning processing. can be

<Computer configuration example>
Next, the series of processes (positioning method) described above can be performed by hardware or by software. When a series of processes is performed by software, a program that constitutes the software is installed in a general-purpose computer or the like.

FIG. 9 is a block diagram showing a configuration example of one embodiment of a computer in which a program for executing the series of processes described above is installed.

The program can be recorded in advance in the hard disk 105 or ROM 103 as a recording medium built into the computer.

Alternatively, the program can be stored (recorded) in a removable recording medium 111 driven by the drive 109. Such a removable recording medium 111 can be provided as so-called package software. Here, the removable recording medium 111 includes, for example, a flexible disk, CD-ROM (Compact Disc Read Only Memory), MO (Magneto Optical) disk, DVD (Digital Versatile Disc), magnetic disk, semiconductor memory, and the like.

It should be noted that the program can be installed in the computer from the removable recording medium 111 as described above, or can be downloaded to the computer via a communication network or broadcasting network and installed in the hard disk 105 incorporated therein. That is, for example, the program is transferred from the download site to the computer wirelessly via an artificial satellite for digital satellite broadcasting, or transferred to the computer by wire via a network such as a LAN (Local Area Network) or the Internet. be able to.

The computer incorporates a CPU (Central Processing Unit) 102 , and an input/output interface 110 is connected to the CPU 102 via a bus 101 .

The CPU 102 executes a program stored in a ROM (Read Only Memory) 103 according to a command input by the user through the input/output interface 110 by operating the input unit 107 or the like. . Alternatively, the CPU 102 loads a program stored in the hard disk 105 into a RAM (Random Access Memory) 104 and executes it.

As a result, the CPU 102 performs the processing according to the above-described flowchart or the processing performed by the configuration of the above-described block diagram. Then, the CPU 102 outputs the processing result from the output unit 106 via the input/output interface 110, transmits it from the communication unit 108, or records it in the hard disk 105 as necessary.

The input unit 107 is composed of a keyboard, mouse, microphone, and the like. Also, the output unit 106 is configured by an LCD (Liquid Crystal Display), a speaker, and the like.

Here, in this specification, the processing performed by the computer according to the program does not necessarily have to be performed in chronological order according to the order described as the flowchart. In other words, processing performed by a computer according to a program includes processing that is executed in parallel or individually (for example, parallel processing or processing by objects).

Also, the program may be processed by one computer (processor), or may be processed by a plurality of computers in a distributed manner. Furthermore, the program may be transferred to a remote computer and executed.

Furthermore, in this specification, a system means a set of multiple components (devices, modules (parts), etc.), and it does not matter whether all the components are in the same housing. Therefore, a plurality of devices housed in separate housings and connected via a network, and a single device housing a plurality of modules in one housing, are both systems. .

Also, for example, the configuration described as one device (or processing unit) may be divided and configured as a plurality of devices (or processing units). Conversely, the configuration described above as a plurality of devices (or processing units) may be collectively configured as one device (or processing unit). Further, it is of course possible to add a configuration other than the above to the configuration of each device (or each processing unit). Furthermore, part of the configuration of one device (or processing unit) may be included in the configuration of another device (or other processing unit) as long as the configuration and operation of the system as a whole are substantially the same. .

In addition, for example, this technology can take a configuration of cloud computing in which a single function is shared and processed jointly by multiple devices via a network.

Also, for example, the above-described program can be executed on any device. In that case, the device should have the necessary functions (functional blocks, etc.) and be able to obtain the necessary information.

Also, for example, each step described in the flowchart above can be executed by a single device, or can be shared and executed by a plurality of devices. Furthermore, when one step includes a plurality of processes, the plurality of processes included in the one step can be executed by one device or shared by a plurality of devices. In other words, a plurality of processes included in one step can also be executed as processes of a plurality of steps. Conversely, the processing described as multiple steps can also be collectively executed as one step.

It should be noted that the program executed by the computer may be such that the processing of the steps described in the program is executed in chronological order according to the order described herein, or in parallel, or when the call is made. They may be executed individually at necessary timings such as occasions. That is, as long as there is no contradiction, the processing of each step may be executed in an order different from the order described above. Furthermore, the processing of the steps describing this program may be executed in parallel with the processing of other programs, or may be executed in combination with the processing of other programs.

It should be noted that the multiple techniques described in this specification can be implemented independently as long as there is no contradiction. Of course, it is also possible to use any number of the present technologies in combination. For example, part or all of the present technology described in any embodiment can be combined with part or all of the present technology described in other embodiments. Also, part or all of any of the techniques described above may be implemented in conjunction with other techniques not described above.

<Configuration example combination>
Note that the present technology can also take the following configuration.
(1)
A distance measurement value calculation unit that calculates a distance measurement value indicating a distance between each of the plurality of communication devices and the communication terminal based on communication for distance measurement performed between the plurality of communication devices and the communication terminal. and,
a reliability calculation unit that calculates the reliability of the distance measurement value;
a weight control unit that performs weight control to change the weight for the first positioning position obtained from the measured distance value according to the reliability;
Using the first positioning position weighted according to the weight control and the second positioning position obtained using a positioning technique other than the positioning technique using communication for ranging, the communication A positioning device, comprising: a positioning calculation unit that performs positioning calculation for obtaining a third positioning position to be output as a positioning result of the position of the terminal.
(2)
The positioning device according to (1) above, wherein the reliability calculation unit calculates, as the reliability, a received signal profile represented by average power and reception time when the ranging signal is received.
(3)
According to (1) or (2) above, the reliability calculation unit calculates, as the reliability, a variance of the plurality of distance measurement values obtained by performing the plurality of distance measurement communications. Positioning device.
(4)
According to any one of (1) to (3) above, the reliability calculation unit calculates, as the reliability, a communication success rate indicating a success rate when a plurality of communications for distance measurement are performed. positioning device.
(5)
The communication for distance measurement is performed with the packet for data communication added,
The reliability calculation unit calculates, as the reliability, a ratio indicating how much error occurred in the data stored in the packet for data communication. ), the positioning device according to any one of
(6)
When the reliability of at least three or more of the measured distance values is high, the weight control unit performs the weight control so that the weight for the first positioning position is increased. Above (1) to (5) ), the positioning device according to any one of
(7)
When the first measured position is not within a range surrounded by the plurality of communication devices, the positioning calculation unit weights the first measured position so as to reduce the weight to calculate the third measured position. The positioning device according to any one of (1) to (6) above, which performs a desired positioning calculation.
(8)
The positioning technology uses the communication for ranging according to the UWB (Ultra Wide Band) standard,
The positioning device according to any one of (1) to (7) above, wherein the other positioning technique uses geomagnetism, or uses acceleration and angular velocity.
(9)
A positioning device that performs positioning processing
calculating a distance measurement value indicating a distance between each of the plurality of communication devices and the communication terminal based on communication for ranging performed between the plurality of communication devices and the communication terminal;
calculating a reliability for the measured distance value;
performing weight control for changing the weight for the first positioning position obtained from the measured distance value according to the reliability;
Using the first positioning position weighted according to the weight control and the second positioning position obtained using a positioning technique other than the positioning technique using communication for ranging, the communication A positioning method comprising: performing a positioning calculation for obtaining a third positioning position to be output as a positioning result of the position of the terminal.
(10)
In the computer of the positioning device that performs positioning processing,
calculating a distance measurement value indicating a distance between each of the plurality of communication devices and the communication terminal based on communication for ranging performed between the plurality of communication devices and the communication terminal;
calculating a reliability for the measured distance value;
performing weight control for changing the weight for the first positioning position obtained from the measured distance value according to the reliability;
Using the first positioning position weighted according to the weight control and the second positioning position obtained using a positioning technique other than the positioning technique using communication for ranging, the communication A program for executing positioning processing including: performing positioning calculation for obtaining a third positioning position to be output as a positioning result of the position of the terminal.

It should be noted that the present embodiment is not limited to the embodiment described above, and various modifications are possible without departing from the gist of the present disclosure. Moreover, the effects described in this specification are merely examples and are not limited, and other effects may be provided.

11 positioning system, 12 UWB anchor, 13 ranging server, 14 mobile terminal, 21 geomagnetic sensor, 22 acceleration sensor, 23 gyro, 24 UWB communication unit, 25 PDR processing unit, 26 UWB distance measurement calculation unit, 27 reliability calculation unit , 28 weight control unit, 29 positioning calculation unit

Claims

A distance measurement value calculation unit that calculates a distance measurement value indicating a distance between each of the plurality of communication devices and the communication terminal based on communication for distance measurement performed between the plurality of communication devices and the communication terminal. and,
a reliability calculation unit that calculates the reliability of the distance measurement value;
a weight control unit that performs weight control to change the weight for the first positioning position obtained from the measured distance value according to the reliability;
Using the first positioning position weighted according to the weight control and the second positioning position obtained using a positioning technique other than the positioning technique using communication for ranging, the communication A positioning device, comprising: a positioning calculation unit that performs positioning calculation for obtaining a third positioning position to be output as a positioning result of the position of the terminal.
The positioning device according to claim 1, wherein the reliability calculation unit calculates a received signal profile represented by average power and reception time when the ranging signal is received as the reliability.
The positioning device according to claim 1, wherein the reliability calculation unit calculates, as the reliability, a variance of the plurality of distance measurement values obtained by performing a plurality of communication for distance measurement.
The positioning device according to claim 1, wherein the reliability calculation unit calculates, as the reliability, a communication success rate indicating a success rate when a plurality of communications for distance measurement are performed.
The communication for distance measurement is performed with the packet for data communication added,
The positioning according to claim 1, wherein the reliability calculation unit calculates, as the reliability, a ratio indicating how much error occurred in data stored in the packet for data communication. Device.
2. The positioning according to claim 1, wherein when the reliability of at least three or more of the measured distance values is high, the weight control unit performs the weight control so that the weight for the first positioning position is increased. Device.
When the first measured position is not within a range surrounded by the plurality of communication devices, the positioning calculation unit weights the first measured position so as to reduce the weight to calculate the third measured position. The positioning device according to claim 1, which performs a desired positioning calculation.
The positioning technology uses the communication for ranging according to the UWB (Ultra Wide Band) standard,
The positioning device according to claim 1, wherein the other positioning technique is one that uses geomagnetism or one that uses acceleration and angular velocity.
A positioning device that performs positioning processing
calculating a distance measurement value indicating a distance between each of the plurality of communication devices and the communication terminal based on communication for ranging performed between the plurality of communication devices and the communication terminal;
calculating a reliability for the measured distance value;
performing weight control for changing the weight for the first positioning position obtained from the measured distance value according to the reliability;
Using the first positioning position weighted according to the weight control and the second positioning position obtained using a positioning technique other than the positioning technique using communication for ranging, the communication A positioning method comprising: performing a positioning calculation for obtaining a third positioning position to be output as a positioning result of the position of the terminal.
In the computer of the positioning device that performs positioning processing,
calculating a distance measurement value indicating a distance between each of the plurality of communication devices and the communication terminal based on communication for ranging performed between the plurality of communication devices and the communication terminal;
calculating a reliability for the measured distance value;
performing weight control for changing the weight for the first positioning position obtained from the measured distance value according to the reliability;
Using the first positioning position weighted according to the weight control and the second positioning position obtained using a positioning technique other than the positioning technique using communication for ranging, the communication A program for executing positioning processing including: performing positioning calculation for obtaining a third positioning position to be output as a positioning result of the position of the terminal.