JP2009052948A - Position measuring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position measuring method capable of measuring an installation position of a base station having an unknown installation position, even when a radio wave does not reach between a base station having a known installation position and the base station having an unknown installation position. <P>SOLUTION: This method has the first step wherein transmission/reception of a radio ranging signal is performed between each of the base stations R1, R2 having each known installation position and a measuring object base station B1 having an unknown position and a moving station P, which is to be executed respectively when the movable moving station P is on each position P1, P2, and the position of the moving station P is determined based on a plurality of distance information between the base stations R1, R2 and the moving station P, and a distance to the measuring object base station B1 is also determined; and the second step for determining the installation position of the measuring object base station B1 based on a plurality of position information of the moving station P and a plurality of distance information between the moving station P and the measuring object base station B1 determined in a plurality of times in the first step, which is to be executed after executing the first step in a plurality of times. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a radio positioning system for measuring a position of a mobile station by transmitting and receiving a radio ranging signal for measuring a distance between the plurality of base stations and a mobile station by measuring a propagation time. The present invention relates to a position measurement method for measuring the position of a base station whose installation position is unknown.

  Conventionally, as a method for measuring the position of a base station whose installation position is unknown, for example, a radio wave transmitted from an antenna of an unknown position station is transmitted with directional antennas (loop antenna, Adcock antenna, etc.) of two radio direction measurement stations. Each is received, and the received radio waves are output to the direction measuring units of the two radio direction measuring stations. The two direction measuring units respectively measure the arrival directions of the radio waves received by the two antennas, and send the measurement results to the positioning station via the connection line. In the positioning station, a position measurement method is disclosed in which an intersection of radio wave arrival directions transmitted from two direction measurement units is obtained and the intersection is specified as the position of the unknown position station (see Patent Document 1). This position measurement method has a problem in that position measurement cannot be performed because the two radio wave arrival directions do not form an intersection, or a large measurement error occurs and position measurement cannot be performed accurately.

  In addition to the above method of measuring the position of an unknown station from the direction of arrival of radio waves, as shown below, wireless ranging signals are transmitted and received between base stations, and the round-trip propagation required Wireless positioning systems that measure the distance between base stations from time are also known.

  FIG. 14 is a schematic diagram of a wireless positioning system that measures the distance between base stations from the round-trip time of radio waves.

  As shown in FIG. 14, this radio positioning system transmits and receives radio ranging signals between a plurality of base stations R whose positions are fixed and a mobile station P that is movable, and base station R from the time required for the round-trip propagation. Is measured between the plurality of base stations R and the mobile stations P, and the position of the mobile station P is obtained.

In this wireless positioning system, the position of the base station Ri is (Xi, Yi), the position of the mobile station P is (x, y), the number of base stations i is n, and the distance between the base station Ri and the mobile station P is Li. (Xi−x) ² + (Yi−y) ² = Li (i = 1 to n) (1)
The following simultaneous equations are obtained. Here, if n = 2, an exact solution can be obtained, and if n> 2, for example, a least square solution can be obtained.

  In the case of two-dimensional positioning, it is possible to solve the simultaneous equations even when n = 2, but when the mobile station moves to a location far enough not to receive radio waves from the base station, If there are obstacles that block radio waves between the two, the number of base stations may be insufficient. Therefore, it is necessary to measure and initialize the number of base stations necessary for the environmental conditions of the wireless positioning system.

  However, the more base stations that should be initialized, the more complicated it becomes to measure the positions of those base stations. Therefore, it is conceivable to initialize the position of the base station whose position is unknown by the following method.

  FIG. 15 is a diagram illustrating a method of initially setting the position of a base station whose installation position is unknown.

  In FIG. 15, the positions of the base stations B1 and B2 whose installation positions are unknown are measured in addition to the two reference stations R1 and R2 that have been initially set by means such as a measure. An example is shown for attempting to initialize the location of two base stations. In such a case, as shown in FIG. 15, wireless ranging signals are transmitted and received between the reference stations R1 and R2 and the base stations B1 and B2, and each reference station and each base are determined from the round-trip propagation time. By measuring the distance between the stations, that is, R1-B1, R1-B2, R2-B1, R2-B2, and B1-B2, the positions of the base stations B1 and B2 can be obtained and initialized.

  However, as described below, when the radio wave does not reach between the base stations for some reason, the position of the base station cannot be initialized.

  FIG. 16 is a diagram illustrating a state in which radio waves do not reach between a reference station whose installation position is known and a base station whose installation position is unknown.

As shown in FIG. 16A, the reference stations R1 and R2 whose installation positions are known and the base station B1 whose installation position is unknown are far away from each other beyond the range where radio waves reach, or FIG. As shown in b), the position of the base station B1 cannot be specified when there is an obstacle H that blocks radio waves in the middle. For example, when a robot moves to a place where the robot cannot communicate with the reference station due to an obstacle H that blocks radio waves in a robot system that performs various processing by moving the robot freely in a building composed of a plurality of rooms. The position of the robot cannot be specified, and the robot falls into an uncontrollable state.
JP 07-280911 A

  In view of the above circumstances, the present invention measures the installation position of a base station whose installation position is unknown even when radio waves do not reach between the base station whose installation position is known and a base station whose installation position is unknown. An object is to provide a position measurement method that can be used.

  A first position measurement method of the present invention that achieves the above object comprises a plurality of base stations fixedly installed at respective installation positions and a movable mobile station, wherein the plurality of base stations, the mobile station, Measurement target that is a base station whose installation position is unknown in a wireless positioning system that measures the position of the mobile station by transmitting and receiving wireless ranging signals that measure the distance between each other by measuring the time required for propagation In the position measurement method for measuring the installation position of a base station, a plurality of installation positions of the plurality of base stations that are each executed when the mobile station is moved and the mobile station is at each of a plurality of positions. Wireless ranging signals are transmitted and received between each of the reference station and the measurement target base station and the mobile station, and the position of the mobile station is determined based on a plurality of distance information between the plurality of reference stations and the mobile station. The above measurement target base A first step for obtaining a distance between the mobile station, a plurality of position information of the mobile station, and the mobile station obtained after the first step is executed a plurality of times And a second step of obtaining an installation position of the measurement target base station based on a plurality of distance information between the measurement target base station and the measurement target base station.

  According to the first position measurement method of the present invention, a mobile station is interposed between a plurality of reference stations whose installation positions are known and a measurement target base station, and the position of the mobile station is measured and measured from the mobile station. Since the operation of measuring the distance to the target base station is repeated a plurality of times, the installation position of the measurement target base station can be measured by interposing the mobile station in the middle.

  Here, the wireless positioning system uses a plurality of mobile stations for measuring the installation position of the measurement target base station, and causes each of the plurality of mobile stations to execute the first step at least once. The second step may determine the installation position of the measurement target base station based on the plurality of position information and the plurality of distance information obtained by the plurality of first steps for the plurality of mobile stations. Good.

  When the first position measurement method of the present invention is configured as described above, the first step and the second step are performed using a plurality of mobile stations, so that the reference station and the measurement target base station Even when communication cannot be performed with the mobile station, the installation position of the measurement target base station can be measured more quickly or with higher accuracy by interposing a plurality of mobile stations in the middle.

  The measurement target base station obtained in the second step has a third step for determining whether or not the position measurement accuracy of the measurement target base station obtained in the second step satisfies a predetermined accuracy. When the position measurement accuracy is determined not to satisfy the predetermined accuracy, the mobile station is moved to another position, the first step is executed, and the second step is executed again. Also good.

  When the first position measurement method of the present invention is configured as described above, when the position cannot be measured with a predetermined accuracy, the mobile station is moved to another position and the first step and the second step are executed. Therefore, the installation position of the measurement target base station can be measured with a predetermined accuracy.

  Further, the mobile station is moved linearly and the first step is repeated, and the third step is performed while the position of the measurement target base station obtained in the second step repeats the first step. Determining that the position measurement accuracy of the measurement target base station does not satisfy the predetermined accuracy when the mobile station exists within a predetermined angle in the forward direction of movement of the mobile station, and in the third step, When it is determined that the position measurement accuracy does not satisfy the predetermined accuracy, the mobile station is moved in a direction that forms an angle with the previous movement direction, and the first step and the second step are executed again. You may do it.

  When the first position measurement method of the present invention is configured as described above, the mobile station is moved linearly and the first step is repeated, and the position measurement accuracy of the measurement target base station satisfies the predetermined accuracy. If it is determined that the mobile station does not move, the mobile station is moved in a direction different from the previous moving direction and the first step and the second step are executed again. The installation position of the base station can be measured.

  The second position measuring method of the present invention that achieves the above object comprises a plurality of base stations fixedly installed at each installation position and a movable mobile station, wherein the plurality of base stations and the mobile It is a base station whose installation position is unknown in a radio positioning system that measures the position of the mobile station by transmitting and receiving radio ranging signals that measure the distance between each other by measuring the time required for propagation with the station In the position measurement method for measuring the installation position of a measurement target base station, the mobile station includes a sensor for measuring a movement direction and a movement distance regardless of transmission / reception of a radio ranging signal, and the plurality of base stations A first step of measuring the position of the mobile station by transmitting and receiving a radio ranging signal between the station and the mobile station, and a plurality of times after the execution of the first step, while operating the sensor Move the above mobile station A second step of measuring a distance between the mobile station and the measurement target base station by transmitting and receiving a radio ranging signal between the mobile station and the measurement target base station; and the first step And a third step of determining the position of the measurement target base station based on the measurement result in the second step.

  According to the second position measurement method of the present invention, since the installation position of the measurement target base station is measured using a mobile station equipped with an autonomous sensor, communication is performed between the reference station and the measurement target base station. Even if it is not possible, the installation position of the measurement target base station can be quickly measured by interposing a mobile station having an autonomous sensor in the middle.

  The third position measuring method of the present invention that achieves the above object comprises a plurality of base stations fixedly installed at each installation position and a movable mobile station, wherein the plurality of base stations and the mobile It is a base station whose installation position is unknown in a radio positioning system that measures the position of the mobile station by transmitting and receiving radio ranging signals that measure the distance between each other by measuring the time required for propagation with the station In the position measurement method for measuring the installation position of the measurement target base station, the mobile station performs constant-velocity linear motion, and the mobile station and the plurality of base stations move while performing constant-velocity linear motion on the mobile station. A first step of determining the position, moving speed, and moving direction of the mobile station by measuring the position of the mobile station a plurality of times by transmitting and receiving radio ranging signals to and from the station; While moving in a straight line, And a second step of measuring a distance between the mobile station and the measurement target base station a plurality of times by transmitting and receiving a radio ranging signal between the station and the measurement target base station. .

  According to the third position measurement method of the present invention, the installation position of the measurement target base station is measured by the first step and the second step while causing the mobile station to perform a constant velocity linear motion. The installation position of the measurement target base station can be measured well and more quickly.

  Moreover, it is preferable to use an impulse signal as the wireless ranging signal.

  When the first and second position measurement methods of the present invention are configured as described above, the installation position of the measurement target base station can be measured with higher accuracy.

  According to the position measurement method of the present invention, even when radio waves do not reach between a base station whose installation position is known and a base station whose installation position is unknown, the position of the base station whose installation position is unknown is measured. It is possible to realize a position measurement method that can

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing the distance measurement principle of the position measurement method of the present invention.

  As shown in FIG. 1, the mobile station P transmits a radio ranging signal 1 to the base station R, and receives a radio ranging signal 2 transmitted from the base station R that has received the radio ranging signal 1. The mobile station P obtains the distance between the mobile station P and the base station R from the round trip time by measuring the round trip time from transmission of the radio ranging signal 1 to reception of the radio ranging signal 2. be able to.

  Instead of obtaining the distance at the mobile station P, the base station R transmits a radio ranging signal to the mobile station P, and receives the radio ranging signal transmitted from the mobile station P that has received the radio ranging signal. The base station R may obtain the distance.

  Usually, the mobile station P and the base station R are not time synchronized. Thus, for example, the radio ranging signal 1 is transmitted from the mobile station P to the base station R at time Tt1, the base station R receives the radio ranging signal 1 at time Tr1, and then the base station R at time Tt2. Transmits the radio ranging signal 2 to the mobile station P, and the mobile station P receives the radio ranging signal 2 at time Tr2.

Here, if the distance between the mobile station P and the base station R is L1, the timer offset between the mobile station P and the base station R is T0, and the speed of light is Vc,
Tr1 + T0 = Tt1 + L1 / Vc,
Tr2-T0 = Tt2 + L1 / Vc (1)
Because
L1 = Vc {(Tr2-Tt1)-(Tt2-Tr1)} / 2 (2)
Thus, the distance L1 between the mobile station P and the base station R is obtained from the equation (2). Note that (Tt2-Tr1) in the equation (2) represents a time difference from the transmission time Tr1 to the reception time Tt2 in the base station R, and the mobile station P transmits the radio ranging signal 1 and transmits the radio signal. When the distance measurement signal 2 is received and the calculation of the expression (2) is performed, the mobile station P is obtained by adding the time difference data (Tt2-Tr1) to the wireless distance measurement signal 2 transmitted from the base station R. To send to.

  Next, a first embodiment will be described.

  The first embodiment corresponds to an example of the first position measuring method of the present invention.

  FIG. 2 is a block diagram illustrating device configurations of the base station and the mobile station in the first embodiment.

  The base station and the mobile station basically have the same device configuration. As shown in FIG. 2, the base station and mobile station include an MPU (Micro Processing Unit) 101 that controls the entire apparatus 100, and PPM data modulation that performs pulse position modulation (PPM) of transmission data output from the MPU 101. Unit 102, an impulse generation unit 103 that generates an impulse sequence having a short time from a PPM-modulated pulse sequence, a bandpass filter 104 that limits a band on the impulse sequence generated by the impulse generation unit 103, and an impulse that has passed through the bandpass filter 104 From a power amplifier 105 that amplifies the power of the column, a transmission antenna 106 that emits the amplified radio wave into the air, a timer 107, a transmission time holding unit 108 that holds the time when the radio wave was transmitted, and other base stations and mobile stations Receiving antenna that receives transmitted impulse radio waves 110, a band-pass filter 111 that filters the impulse train input from the receiving antenna 110, a low-noise amplifier 112 that amplifies the impulse train power, a pulse detection that includes a pulse-detecting envelope detector circuit and a comparator, etc. 113, a PN sequence generator 114 for generating a PN (pseudorandom signal) sequence, a correlation for comparing a pulse detected by the pulse detector 113 and a PN sequence generated by the PN sequence generator 114 by a digital matched filter 115 and PPM data demodulating section 116 for demodulating received data determined by the correlator 115 into received data and inputting the received data to MPU 101. Also provided is a reception time holding unit 117 for holding the reception time when the radio wave is received, which is necessary for calculating the distance from the round trip time of the radio wave.

  In the first embodiment, in order to improve measurement accuracy, an ultra-wideband (UWB) impulse radio wave is used. However, the position measurement method of the present embodiment is not limited to the impulse radio wave, and a spread spectrum signal such as a wireless LAN may be used.

  Next, the operation of the apparatus 100 will be described.

  Transmission data output from the MPU 101 is sent to the PPM data modulation unit 102. The PPM data modulator 102 randomizes the transmission data pulse interval with a unique pseudo-random signal (PN) sequence for each wireless channel, and further changes the pulse position according to 1/0 of the pulse position modulation (PPM). )I do. The PPM-modulated pulse train is converted into an impulse train having a very short ns order by the impulse generator 103, and further filtered by the band-pass filter 104 to a frequency defined by the Radio Law, and then by the power amplifier 105. The power is amplified and emitted as radio waves from the transmitting antenna 106 into the air. The transmission time when the pulse train is transmitted is held in the transmission time holding unit 108.

  On the other hand, an impulse radio wave transmitted from another base station or mobile station is received by the receiving antenna 110, and unnecessary frequency components are removed by the band pass filter (BPF) 111, and then amplified by the low noise amplifier 112. The pulse is detected by the pulse detector 113. The detected pulse is compared with a PN sequence generated by the PN sequence generation unit 114 in the correlator 115 using a digital matched filter, and the data determined by the correlator 115 as a normal pulse train is the PPM data demodulation unit 116. Is demodulated as received data and input to the MPU 101. The reception time when the pulse train is received is held in the reception time holding unit 117.

  Based on the transmission time held in the transmission time holding unit 108 and the reception time held in the reception time holding unit 117, the MPU 101 calculates the distance to the partner station based on the distance measurement principle described with reference to FIG. .

  Next, the position measuring method according to the first embodiment of the present invention will be described.

  FIG. 3 is a schematic diagram showing a position measurement method according to the first embodiment of the present invention.

  As shown in FIG. 3, the position measurement method of the present embodiment is such that the two reference stations R1 and R2 fixedly installed at the respective installation positions and the measurement target base station B1 are far away from each other and cannot be directly measured. Used in any case. That is, by using the mobile station P that is movable, the base station R1, R2 and the mobile station P transmit and receive a radio ranging signal that measures the distance between them by measuring the time required for propagation, thereby transmitting the mobile station P. The position of the measurement target base station B1, which is a base station whose installation position is unknown, is measured by a wireless positioning system that measures the positions P1 and P2, and includes the following two steps.

  That is, in the first step, when the mobile station P is moved and the mobile station P is at the position P1, each of the two reference stations R1 and R2 whose measurement positions are known and the measurement target base station B1 and the mobile station P A wireless ranging signal is transmitted and received between the two reference stations R1, R2 and the mobile station P, the position of the mobile station P is obtained based on the distances 3 and 4, and the distance to the measurement target base station B1 5 is determined. Next, the mobile station P is moved, and when the mobile station P is at the position P2, wireless measurement is performed between each of the two reference stations R1, R2 whose measurement positions are known and the measurement target base station B1 and the mobile station P. A distance signal is transmitted and received, and the position of the mobile station P is obtained based on the distances 6 and 7 between the two reference stations R1 and R2 and the mobile station P, and the distance 8 between the measurement target base station B1 is obtained.

  In the second step, after the first step is executed twice, the position information of the mobile station P at the position P1 and the position P2 obtained in the first two steps, the mobile station P and the measurement target base are obtained. The installation position of the measurement target base station B1 is obtained based on the two distance information 5 and 8 between the station B1.

In FIG. 3, the coordinates of the reference stations R1, R2 whose positions are known are (Xr1, Yr1), (Xr2, Yr2), the coordinates of the measurement target base station B1 are (xb1, yb1), and the mobile station position P1, position P2. Are (xp1, yp1), (xp2, yp2), and the distances from the reference stations R1, R2 and the measurement target base station B1 at the position P1 of the mobile station are LrlP1, Lr2P1, Lblp1, and the position at the position P2 of the mobile station When the distances from the reference stations R1, R2 and the measurement target base station B1 are Lrlp2, Lr2p2, Lblp2,
(Xr1-xp1) ² + (Yr1-yp1) ² = Lrlp1 ²
(Xr2-xp1) ² + (Yr2-yp1) ² = Lr2p1 ²
(Xb1-xp1) ² + (yb1-yp1) ² = Lb1P1 ²
(Xr1-xp2) ² + (Yr1-yp2) ² = Lr1P2 ²
(Xr2-xp2) ² + (Yr2-yp2) ² = Lr2p2 ²
(Xb1-xp2) ² + (yb1-yp2) ² = Lb1P2 ² (3)
The following simultaneous equations are obtained.

  This equation (3) can be solved because there are six unknowns xp1, yp1, xp2, yp2, xb1, yb1 and six equations.

  This calculation is executed by the MPU 101 (see FIG. 2) of the mobile station, and the position of the measurement target base station B1 is obtained as coordinates (xb1, yb1). The measurement target base station B1 whose position is specified in this way is a base station for measuring the position of another base station whose position is unknown by initializing the position as one of base stations whose installation positions are known. It can be used as a station.

  Next, an initial setting procedure of the measurement target base station in the first embodiment will be described.

  FIG. 4 is a flowchart illustrating a procedure for initially setting the position of the measurement target base station using the position measurement method according to the first embodiment.

  As shown in FIG. 4, the mobile station P moves to an arbitrary position P1 within the radio wave reach from the reference stations R1 and R2 (step S01), and the mobile station P measures the distance Lrlp1 with the reference station R1 (step S01). Subsequently, the mobile station P measures the distance Lr2p1 from the reference station R2 (step S03). Next, the mobile station P measures the distance Lb1p1 from the measurement target base station B1 (step S04). Next, the coordinates at the position P1 of the mobile station P are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlp1 and Lr2p1 (step S05).

  Next, the mobile station moves to an arbitrary position P2 within the radio wave reach from the reference stations R1 and R2 (step S06), and the mobile station P measures the distance Lrlp2 with the reference station R1 (step S07), and then moves. The station P measures the distance Lr2p2 from the reference station R2 (step S08). Next, the mobile station P measures the distance Lb1p2 from the measurement target base station B1 (step S09). Next, the coordinates at the position 2 of the mobile station P are calculated from the coordinates of the reference stations R1, R2 and the distances Lrlp2, Lr2p2 (step S10).

  Next, the coordinates of the measurement target base station B1 are calculated from the coordinates of the mobile station P at the position P1, the coordinates at the position P2, and the distances Lblp1 and Lb1p2 (step S11), and the initial position is set as the position of the measurement target base station B1. Set (step S12).

  In addition, when initializing the coordinates of a plurality of measurement target base stations, the process according to the flowchart of FIG. 4 may be repeatedly executed for the plurality of measurement target base stations, but the mobile station P is located at the position P1 (see FIG. 3). The distance may be measured sequentially with all the measurement target base stations that can communicate with each other.

  In the above description, the case of two-dimensional positioning on a plane has been described. However, in the case of three-dimensional positioning, coordinates in the height direction can be obtained in the same manner. In the case of three-dimensional positioning, at least three reference stations are necessary, and at least three positions where the mobile station moves are also necessary.

  Further, in the first embodiment, the example in which the reference stations R1 and R2 and the measurement target base station B1 are separated and cannot be directly measured has been described, but the distance measurement of the measurement target base station B1 out of the two reference stations is performed. If there is at least one reference station that can measure the distance from the base station that can measure the distance to the base station to be measured without going through the mobile station, the measurement target from the other reference station that cannot be directly measured The distance to the base station may be measured in the first embodiment.

  In the above description, an example of using this position measurement method at the time of initial setting of the base station has been described. However, for example, the position of the base station may change for some reason. The position of the base station may be initialized at regular intervals with respect to the occurrence of or when an abnormality is detected.

  Next, a second embodiment will be described.

  The second embodiment corresponds to a modification of the first embodiment. In the second embodiment, the wireless positioning system uses a plurality of mobile stations for measuring the installation position of the measurement target base station, and the first step is performed at least once for each of the plurality of mobile stations. In the second step, the installation position of the measurement target base station is obtained based on a plurality of position information and a plurality of distance information obtained by a plurality of first steps for a plurality of mobile stations.

  In the second embodiment, the same base station and mobile station as those having the device configuration described with reference to FIG. 2 are used.

  FIG. 5 is a schematic diagram illustrating a position measurement method according to the second embodiment.

  As shown in FIG. 5, in this second embodiment, two mobile stations P and Q are used, and there are three destination positions to which each mobile station P and Q moves. In addition, the mobile stations P and Q operate simultaneously in parallel.

  First, mobile station P and mobile station Q perform the first step at position P1 and position Q1, respectively, and then mobile station P and mobile station Q move to position P2 and position Q2, respectively, and execute the first step. Then, the mobile station P and the mobile station Q move to the position P3 and the position Q3, respectively, and execute the first step, and then execute the second step.

In the example of FIG. 5, the coordinates of the reference stations R1, R2 whose installation positions are known are (Xr1, Yr1), (Xr2, Yr2), the coordinates of the measurement target base station B1 are (xb1, yb1), and the position Pi of the mobile station P The coordinates at (i = 1 to 3) are (xpi, ypi), the coordinates at the position Qi (i = 1 to 3) of the mobile station Q are (xqi, yqi), and the reference station at the position Pi of the mobile station P When the distances from R1, R2 and the measurement target base station B1 are Lrlpi, Lr2pi, Lblpi, and the distances from the reference stations R1, R2 and the measurement target base station B1 at the position Qi of the mobile station Q are Lr1qi, Lr2qi, Lb1qi,
(Xr1-xpi) ² + (Yr1-ypi) ² = Lrlpi ² (i = 1 to 3)
(Xr2-xpi) ² + (Yr2-ypi) ² = Lr2pi ²
(Xb1-xpi) ² + (Yb1-ypi) ² = Lrlqi ²
(Xr1-xqi) ² + (Yr1-yqi) ² = Lr1qi ²
(Xr2-xqi) ² + (Yr2-yqi) ² = Lr2qi ²
(Xb1-xqi) ² + (Yb1-yqi) ² = Lblqi ² (4)
The following simultaneous equations are obtained.

  This equation (4) has 14 unknowns xpi, ypi, xqi, yqi, xb1, yb1, and is a redundant equation because there are 18 equations. This is because an error is included in the actual distance measurement result, so that the position measurement error of the measurement target base station is reduced by solving this redundant expression using the least square method that minimizes the square error. is there.

  Note that the number of mobile stations to be used and the number of positions at which the mobile stations perform distance measurement are not limited to two and three, respectively. Increasing the number increases the time. However, the position of the base station can be measured with higher accuracy.

  FIG. 6 is a flowchart illustrating a procedure for initially setting the position of the measurement target base station using the position measurement method according to the second embodiment.

  As shown in FIG. 6, the mobile station P moves to an arbitrary position P1 within the radio wave reach from the reference stations R1 and R2 (step S21), and the mobile station P has distances Lrlp1 and Lr2p1 from the reference stations R1 and R2, and The distance Lb1p1 with the measurement target base station B1 is measured (step S22), and then the coordinates at the position P1 of the mobile station P are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlp1 and Lr2p1 (step S23).

  Next, the mobile station P moves to an arbitrary position P2 within the radio wave arrival range from the reference stations R1 and R2 (step S24), and the mobile station P has distances Lrlp2 and Lr2p2 from the reference stations R1 and R2 and the measurement target base station B1. The distance Lb1p2 is measured (step S25), and then the coordinates at the position P2 of the mobile station P are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlp2 and Lr2p2 (step S26).

  Next, the mobile station P moves to an arbitrary position P3 within the radio wave arrival range from the reference stations R1 and R2 (step S27), and the mobile station P has distances Lrlp3 and Lr2p3 from the reference stations R1 and R2 and the measurement target base station B1. The distance Lb1p3 is measured (step S28), and then the coordinates at the position P3 of the mobile station P are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlp3 and Lr2p3 (step S29).

  On the other hand, the mobile station Q moves to an arbitrary position Q1 within the radio wave reachable range from the reference stations R1 and R2 (step S31), and the mobile station Q is separated from the reference stations R1 and R2 by the distances Lrlq1 and Lr2q1 and the measurement target base station B1. Distance Lb1q1 is measured (step S32), and then the coordinates at the position Q1 of the mobile station Q are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlq1 and Lr2q1 (step S33).

  Next, the mobile station Q moves to an arbitrary position Q2 within the radio wave reach from the reference stations R1 and R2 (step S34), and the mobile station Q has distances Lrlq2 and Lr2q2 from the reference stations R1 and R2 and the measurement target base station B1. The distance Lb1p2 is measured (step S35), and then the coordinates at the position Q2 of the mobile station Q are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlq2 and Lr2q2 (step S36).

  Next, the mobile station Q moves to an arbitrary position Q3 within the radio wave reach from the reference stations R1 and R2 (step S37), and the mobile station Q has distances Lrlq3 and Lr2q3 from the reference stations R1 and R2 and the measurement target base station B1. The distance Lb1q3 is measured (step S38), and then the coordinates of the mobile station Q at the position Q3 are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlq3 and Lr2q3 (step S39).

  Next, the coordinates of the measurement target base station B1 are calculated from the coordinates of the positions P1, P2, P3, Q1, Q2, Q3 and the distances Lblp1, Lb1p2, Lblp3, Lblq1, Lb1q2, Lblq3 (step S40). Initially set as the position of the measurement target base station B1 (step S41).

  As described above, according to the present embodiment, the first step is executed at least once for each of the plurality of mobile stations, and in the second step, the first step is performed for the plurality of mobile stations. The installation position of the measurement target base station B1 can be accurately measured based on the obtained plurality of position information and the plurality of distance information.

  Next, a third embodiment will be described.

  The third embodiment corresponds to a modification of the first embodiment. The third embodiment has a third step of determining whether or not the position measurement accuracy of the measurement target base station obtained in the second step satisfies a predetermined accuracy, and is obtained in the second step. When it is determined that the position measurement accuracy of the measurement target base station does not satisfy a predetermined accuracy, the mobile station is moved to another position, the first step is performed, and then the second step is performed again. To do.

  In the third embodiment, the same base station and mobile station as those described with reference to FIG. 2 are used.

  FIG. 7 is a schematic diagram illustrating a position measurement method according to the third embodiment.

  In the third embodiment, the mobile station is not moved arbitrarily, but is moved to a position where the position measurement error becomes small. For example, in FIG. 7, after measuring the distance between the mobile station P and the measurement target base station B1 at the position P1, the user moves to the position P2 and measures the distance between the mobile station P and the measurement target base station B1 at the position P2. And At this time, if the measurement target base station B1 happens to be in the vicinity of an extension line of the straight line connecting the position P1 and the position P2, the measurement error may increase and the position of the measurement target base station B1 may not be accurately measured.

  That is, when the distance between the mobile station P and the measurement target base station B1 at the position P1 is obtained as r1, it can be seen that the measurement target base station B1 is on the arc A1 with the radius r1 centered on the position P1. Further, when the distance between the mobile station P and the measurement target base station B1 at the position P2 is obtained as r2, it can be seen that the measurement target base station B1 is on the arc A2 with the radius r2 centered on the position P2. Therefore, the intersection of these two arcs A1 and A2 is obtained as the position of the measurement target base station B1. However, if there is a distance measurement error, the arc has a width, and the two arcs A1 and A2 do not become points but a wide area.

  FIG. 8 is a diagram illustrating the effect of the position measurement method according to the third embodiment.

  When the position P1, the position P2, and the measurement target base station B1 after the movement of the mobile station P are arranged substantially in a straight line as shown in FIG. 7, due to the ranging error, FIG. As shown, the arc A1 becomes two arcs 11 and 12, and the arc A2 becomes two arcs 21 and 22. As a result, these four arcs 11, 12, 21, 22 form an elongated crescent-shaped region D. The longer the area D is, the more difficult it is to specify the position of the measurement target base station B1.

  Therefore, in such a case, the third step is measured when the position of the measurement target base station obtained in the second step is within a predetermined angle in the forward direction of the mobile station during the repetition of the first step. When it is determined that the position measurement accuracy of the target base station does not satisfy the predetermined accuracy, and it is determined in the third step that the position measurement accuracy of the measurement target base station does not satisfy the predetermined accuracy, The mobile station is moved in a direction that forms an angle with the previous moving direction, and the first step and the second step are executed again.

  For example, the predetermined angle may be set to about 15 degrees. When the position of the measurement target base station is within this predetermined angle, as shown in FIG. 8A, the length of the region D becomes long, and it becomes difficult to specify the position of the measurement target base station. In the embodiment, the position measurement accuracy of the measurement target base station is estimated by determining whether or not the angle is within the predetermined angle.

  As a result of the determination as to whether or not the angle is within the predetermined angle, if the angle is within the predetermined angle, the position measurement of the measurement target base station B1 using the distance r1 obtained at the position P1 and the distance r2 obtained at the position P2 is stopped. The mobile station P is moved in a direction perpendicular to the moving direction from the position P1 to the position P2 so that the length of the region D formed by one arc is shortened. In other words, the mobile station P is moved to the position P3 on the tangent line G1 at B1 of the arc A1. The distance r3 between the mobile station P and the measurement target base station B1 is measured at the position P3, and the position of the measurement target base station B1 can be obtained from the distance r3 and the distance r1 obtained at the position P1. In this case, as shown in FIG. 8B, since the arcs A2 and A3 intersect with each other in a substantially vertical state, the length of the region D is shortened, and the position measurement deviation of the measurement target base station B1 is , It becomes extremely small as compared with the case of measurement at the position P2.

  FIG. 9 is a flowchart illustrating a procedure for initially setting the position of the measurement target base station using the position measurement method according to the third embodiment.

  As shown in FIG. 9, the mobile station P moves to an arbitrary position P1 within the radio wave reach from the reference stations R1 and R2 (step S51), and the mobile station P has distances Lrlp1 and Lr2p1 from the reference stations R1 and R2, and The distance Lb1p1 with the measurement target base station B1 is measured (step S52), and then the coordinates at the position P1 of the mobile station P are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlp1 and Lr2p1 (step S53).

  Next, the mobile station P moves to an arbitrary position P2 within the radio wave reachable range from the reference stations R1 and R2 (step S54), and the mobile station P has distances Lrlp2 and Lr2p2 from the reference stations R1 and R2 and the measurement target base station B1. The distance Lb1p2 is measured (step S55), and then the coordinates at the position P2 of the mobile station P are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlp2 and Lr2p2 (step S56). Next, the coordinates of the measurement target base station B1 are calculated from the coordinates of the mobile station P and the distances Lblp1 and Lb1p2 (step S57).

  Next, it is determined whether or not the coordinates of the measurement target base station B1 are within a predetermined angle from the extension line of the straight line connecting the position P1 and the position P2 (step S58). Here, the predetermined angle may be set to about 15 degrees, for example.

  As a result of the determination in step S58, if the coordinates of the measurement target base station B1 are in the vicinity of the straight line connecting the position P1 and the position P2, the mobile station P is connected to the tangent line G1 (within the radio wave arrival range from the reference stations R1 and R2). The mobile station P measures the distances Lrlp3 and Lr2p3 with the reference stations R1 and R2 and the distance Lb1p3 with the measurement target base station B1 (step S60). Then, the coordinates at the position P3 of the mobile station P are calculated from the coordinates of the reference stations R1 and R2 and the distances Lrlp3 and Lr2p3 (step S61). Next, the coordinates of the measurement target base station B1 are calculated from the coordinates of the positions P2 and P3 and the distances Lblp2 and Lb1p3 (step S62). Next, the coordinates are initialized as the position of the measurement target base station B1 (step S63). ) End all processing.

  On the other hand, as a result of the determination in step S58, if the coordinates of the measurement target base station B1 are not in the vicinity of the straight line connecting the position P1 and the position P2, the measurement target base is determined from the coordinates of the positions P1, P2 and the distances Lblp1, Lb1p2. The coordinates of the station B1 are calculated (step S64). Next, the coordinates are initialized as the position of the measurement target base station B1 (step S63), and all the processes are terminated.

  Thus, even when the measurement target base station B1 is near the extension of the straight line connecting the position P1 and the position P2, the measurement error is large, and the position of the measurement target base station B1 cannot be measured with high accuracy. Thus, the position of the measurement target base station B1 can be accurately measured.

  Next, a fourth embodiment will be described.

  The fourth embodiment corresponds to an example of the second position measuring method of the present invention.

  The fourth embodiment includes a plurality of base stations fixedly installed at each installation position and a mobile station that can move freely, and the propagation time required between the plurality of base stations and the mobile station is In a wireless positioning system that measures the position of the mobile station by transmitting and receiving wireless ranging signals that measure the distance between each other by measurement, the installation position of the measurement target base station that is a base station whose installation position is unknown is measured In the position measurement method, the mobile station includes a sensor for measuring a moving direction and a moving distance irrespective of transmission / reception of a radio ranging signal, and the radio ranging signal is transmitted between a plurality of base stations and the mobile station. A first step of measuring the position of the mobile station by transmitting and receiving, and a plurality of times after the execution of the first step, moving the mobile station and the sensor while acting, Wireless ranging signal between A second step of measuring the distance between the mobile station and the measurement target base station by communicating, and a position of the measurement target base station based on the measurement results in the first step and the second step 3 steps.

  In addition, in this 4th Embodiment, although the mobile station provided with the autonomous sensor is used, the thing similar to the base station of the apparatus structure demonstrated with reference to FIG. 2 and a mobile station other than that is used. .

  FIG. 10 is a schematic diagram illustrating a position measurement method according to the fourth embodiment.

  In the fourth embodiment, when the mobile station P cannot communicate with the measurement target base station B1 at the position P1, the position measurement is performed using an autonomous sensor provided in a moving body such as a robot or a car. is there. As an autonomous sensor, a sensor that measures a travel distance and a travel speed by a wheel speed sensor and a gyro sensor that detects a change in its own moving direction are widely used. By using these autonomous sensors, the mobile station P can obtain the relative movement amount of its own position.

  Therefore, as shown in FIG. 10, when the mobile station P is at the position P1 where the radio wave does not reach the measurement target base station B1, first, the position P1 is obtained by measuring the distance with the reference stations R1 and R2, and then The mobile station P moves from position P1 to position P2. During the movement, the relative movement amount of the mobile station P from the position P1 to the position P2 is obtained by an autonomous sensor. By doing this, the coordinates of the mobile station P at the position P2 are obtained, and the distance from the position P2 to the measurement target base station B1 is measured. Next, it further moves to position P3. During the movement, the relative movement amount of the mobile station P from the position P2 to the position P3 is obtained by an autonomous sensor. By doing this, the coordinates of the mobile station P at the position P3 are obtained, and the distance from the position P3 to the measurement target base station B1 is measured. The position of the measurement target base station B1 can be obtained based on the distance from the position P2 and the position P3 thus obtained to the measurement target base station B1, and the position can be initialized.

  At this time, it is necessary to select a location where radio waves reach between the measurement target base station B1 as the position P2 and the position P3.

  FIG. 11 is a flowchart illustrating a procedure for initially setting the position of the measurement target base station using the position measurement method according to the fourth embodiment.

  As shown in FIG. 11, the mobile station P moves to an arbitrary position P1 within the radio wave arrival range from the reference stations R1 and R2 (step S71), and the mobile station P measures distances Lr1p1 and Lr2p1 with the reference stations R1 and R2. (Step S72), the coordinates of the position P1 of the mobile station P are calculated from the coordinates of the reference stations R1 and R2 and the distances Lr1p1 and Lr2p1 (Step S73).

  Next, the mobile station P moves by itself to the position P2 within the radio wave reachable range with the measurement target base station B1 while positioning by the autonomous sensor (step S74), and the mobile station P sets the distance Lb1p2 with the measurement target base station B1. Measure (Step S75).

  Next, the mobile station P moves by itself from the position P2 to the position P3 within the radio wave reachable range of the measurement target base station B1 while positioning by the autonomous sensor (step S76), and the mobile station P contacts the measurement target base station B1. The distance Lb1p3 is measured (step S77).

  Next, the coordinates of the measurement target base station B1 are calculated from the coordinates of the positions P2 and P3 and the distances Lblp2 and Lb1p3 (step S78). Next, the coordinates are initialized as the position of the measurement target base station B1 (step S79). ) End all processing.

  Thus, according to the present embodiment, even when the mobile station P cannot communicate with the measurement target base station B1 at the position P1, it uses the autonomous sensor by using the mobile station P equipped with the autonomous sensor. Thus, the position of the measurement target base station B1 can be measured.

  Next, a fifth embodiment will be described.

  The fifth embodiment corresponds to an example of the second position measuring method of the present invention.

  The fifth embodiment includes a plurality of base stations fixedly installed at each installation position and a mobile station that can move freely, and a propagation time required between the plurality of base stations and the mobile station. In a wireless positioning system that measures the position of the mobile station by transmitting and receiving wireless ranging signals that measure the distance between each other by measurement, the installation position of the measurement target base station that is a base station whose installation position is unknown is measured In the position measurement method, the mobile station performs a linear motion at a constant velocity, and transmits a radio ranging signal between the plurality of base stations and the mobile station while causing the mobile station to perform a linear motion at a constant velocity. A first step of determining a position, a moving speed, and a moving direction of the mobile station by measuring the position of the mobile station a plurality of times by transmitting and receiving, and the mobile station while continuing a constant velocity linear motion in the mobile station And the above measurement target base station And a second step multiple times measure the distance between the mobile station and the measurement target base station by transmitting and receiving lines ranging signal.

  The fifth embodiment should also be referred to as an improved example of the fourth embodiment. That is, some of the autonomous sensors used in the fourth embodiment, such as a wheel rotation sensor and a gyro, are likely to accumulate errors. For example, when acceleration such as acceleration / deceleration or direction change occurs, an error occurs in the distance sensor due to slipping of the wheel. Therefore, when driving a long distance while measuring with an autonomous sensor, the autonomous positioning accuracy after traveling decreases. There are things to do.

  Therefore, in the fifth embodiment, position measurement including the first step and the second step as described above is performed.

  In the fifth embodiment, the same base station and mobile station as those described with reference to FIG. 2 are used.

  FIG. 12 is a schematic diagram illustrating a position measurement method according to the fifth embodiment.

  As shown in FIG. 12, in the fifth embodiment, the moving body P performs a constant velocity linear motion so as not to generate acceleration. First, the moving body P starts constant linear motion so that it passes through the radio wave range of the reference stations R1 and R2 and reaches the radio wave reach of the measurement target base station B1, and after the constant linear motion, the reference stations R1, R2 Ranging with reference stations R1 and R2 is performed at position P1 within the radio wave range. In this case, it is assumed that the approximate position of the measurement target base station B1 is known.

  The constant velocity linear motion is continued after obtaining the distances from the reference stations R1 and R2 at the position P1 at time T1, and then the distances from the reference stations R1 and R2 at the position P2 at time T2. Further, when the moving body P continues the constant-velocity linear motion and falls within the radio wave range of the measurement target base station B1, the distance measurement is performed between the measurement target base station B1 at time T3 and the measurement target is further measured at time T4. Ranging with the base station B1 is performed. Since the coordinates of the positions P1 and P2 are known and the velocity vector of the moving body P is known, the positions P3 and P4 are obtained from the times T3 and T4. Thereby, the position of the measurement target base station B1 is obtained.

  FIG. 13 is a flowchart illustrating a procedure for initially setting the position of the measurement target base station using the position measurement method according to the fifth embodiment.

  As shown in FIG. 13, the mobile station P starts constant-velocity linear motion (step S81), and at time T1, the mobile station P is at the reference station R1, R1 at a specific position P1 within the radio wave reach from the reference stations R1, R2. The distances Lr1p1 and Lr2p1 with respect to R2 are measured (step S82), and at time T2, the mobile station P has distances Lr1p2 and Lr2p2 with the reference stations R1 and R2 at a specific position P2 within the radio wave reach from the reference stations R1 and R2. (Step S83), and at time T3, the mobile station P measures the distance Lb1p3 to the measurement target base station B1 at a specific position P3 within the radio wave reach from the measurement target base station B1 (step S84). At time T4, the mobile station P measures the distance Lb1p4 from the measurement target base station B1 at a specific position P4 within the radio wave reach from the measurement target base station B1 ( Step S85).

  Next, the coordinates of the positions P1, P2 of the mobile station P are calculated from the coordinates of the reference stations R1, R2 and the distances Lr1p1, Lr2p1, Lr1p2, Lr2p2 (step S86).

  Next, the coordinates of the positions P3 and P4 of the mobile station P are calculated from the coordinates of the positions P1 and P2 and the times T1, T2, T3 and T4 (step S87). Next, the coordinates of the positions P3 and P4 and the distance Lb1p3 The coordinates of the measurement target base station B1 are calculated from Lb1p4 (step S88). Next, the coordinates are initialized as the position of the measurement target base station B1 (step S89), and all the processes are terminated.

  As described above, according to the present embodiment, even when the mobile station P cannot communicate with the measurement target base station B1 simultaneously with the reference stations R1 and R2, the first step and the first step are performed while causing the mobile station P to perform a uniform linear motion. By performing the two steps, the position of the measurement target base station B1 can be measured with high accuracy.

It is a figure which shows the distance measurement principle of the position measuring method of this invention. It is a block diagram which shows the apparatus structure of the base station and mobile station in 1st Embodiment. It is a schematic diagram which shows the position measuring method of the 1st Embodiment of this invention. It is a flowchart which shows the procedure which initializes the position of a measuring object base station using the position measuring method of 1st Embodiment. It is a schematic diagram which shows the position measuring method in 2nd Embodiment. It is a flowchart which shows the procedure which initializes the position of a measuring object base station using the position measuring method of 2nd Embodiment. It is a schematic diagram which shows the position measuring method in 3rd Embodiment. It is a figure which shows the effect of the position measuring method of 3rd Embodiment. It is a flowchart which shows the procedure which initializes the position of a measuring object base station using the position measuring method of 3rd Embodiment. It is a schematic diagram which shows the position measuring method in 4th Embodiment. It is a flowchart which shows the procedure which initializes the position of a measuring object base station using the position measuring method of 4th Embodiment. It is a schematic diagram which shows the position measuring method in 5th Embodiment. It is a flowchart which shows the procedure which initializes the position of a measuring object base station using the position measuring method of 5th Embodiment. It is a schematic diagram of the radio positioning system which measures the distance between base stations from the round-trip time of a radio wave. It is a figure which shows the method of initial-setting the position of the base station whose installation position is unknown. It is a figure which shows the state which an electromagnetic wave does not reach between the base station with a known installation position, and a base station with an unknown installation position.

Explanation of symbols

1, 2 Wireless ranging signal 3, 4, 5, 6, 7, 8 Distance 11, 12, 21, 22, 31, 32 Arc 100 Device 101 MPU
DESCRIPTION OF SYMBOLS 102 PPM data modulation part 103 Impulse generation part 104 Band pass filter 105 Power amplifier 106 Transmission antenna 107 Timer 108 Transmission time holding part 110 Reception antenna 111 Band pass filter 112 Low noise amplifier 113 Pulse detection part 114 PN sequence generation part 115 Correlator 116 PPM data demodulator 117 Reception time holding unit

Claims (7)

Provided with a plurality of base stations fixedly installed at each installation position and mobile stations that are movable,
Installation in a wireless positioning system that measures the position of the mobile station by transmitting and receiving wireless ranging signals that measure the distance between the plurality of base stations and the mobile station by measuring the time required for propagation In the position measurement method for measuring the installation position of the measurement target base station which is a base station whose position is unknown,
Each of the plurality of reference stations and measurement target base stations whose installation positions are known among the plurality of base stations and the mobile station, which are executed when the mobile station is moved and the mobile station is at each of a plurality of positions. A wireless ranging signal between the plurality of reference stations and the mobile station to obtain a position of the mobile station based on a plurality of distance information, and a distance to the measurement target base station A first step for determining
A plurality of position information of the mobile station and a plurality of positions between the mobile station and the measurement target base station, which are obtained in a plurality of first steps, are executed after the first step is executed a plurality of times. And a second step of obtaining an installation position of the measurement target base station based on distance information. The wireless positioning system uses a plurality of mobile stations for installation position measurement of the measurement target base station, and causes each of the plurality of mobile stations to execute the first step at least once,
The second step is to obtain an installation position of the measurement target base station based on a plurality of position information and a plurality of distance information obtained by a plurality of first steps for the plurality of mobile stations. The position measuring method according to claim 1. A third step of determining whether or not the position measurement accuracy of the measurement target base station obtained in the second step satisfies a predetermined accuracy;
When it is determined that the position measurement accuracy of the measurement target base station obtained in the second step does not satisfy a predetermined accuracy, the mobile station is moved to another position and the first step is executed. The position measuring method according to claim 1, wherein the second step is performed again after that. Moving the mobile station linearly, repeating the first step,
In the third step, when the position of the measurement target base station obtained in the second step is within a predetermined angle in the moving direction of the mobile station while repeating the first step, the measurement target base station The position measurement accuracy is determined not to satisfy a predetermined accuracy, and when it is determined in the third step that the position measurement accuracy of the measurement target base station does not satisfy a predetermined accuracy, the movement 4. The position measuring method according to claim 3, wherein the station is moved in a direction that forms an angle with the moving direction so far, and the first step and the second step are performed again. Provided with a plurality of base stations fixedly installed at each installation position and mobile stations that are movable,
Installation in a wireless positioning system that measures the position of the mobile station by transmitting and receiving wireless ranging signals that measure the distance between the plurality of base stations and the mobile station by measuring the time required for propagation In the position measurement method for measuring the installation position of the measurement target base station which is a base station whose position is unknown,
The mobile station includes a sensor for measuring a moving direction and a moving distance regardless of transmission / reception of a radio ranging signal,
A first step of measuring the position of the mobile station by transmitting and receiving radio ranging signals between the plurality of base stations and the mobile station;
After the execution of the first step, the movement is performed a plurality of times by moving the mobile station while operating the sensor and transmitting / receiving a radio ranging signal between the mobile station and the measurement target base station. A second step of measuring a distance between the station and the base station to be measured;
And a third step of determining a position of the measurement target base station based on measurement results in the first step and the second step. Provided with a plurality of base stations fixedly installed at each installation position and mobile stations that are movable,
Installation in a wireless positioning system that measures the position of the mobile station by transmitting and receiving wireless ranging signals that measure the distance between the plurality of base stations and the mobile station by measuring the time required for propagation In the position measurement method for measuring the installation position of the measurement target base station which is a base station whose position is unknown,
The mobile station performs a uniform linear motion,
The position of the mobile station by measuring the position of the mobile station a plurality of times by transmitting and receiving radio ranging signals between the plurality of base stations and the mobile station while causing the mobile station to perform a linear motion at a constant speed A first step for determining a moving speed and a moving direction;
A plurality of distances between the mobile station and the measurement target base station can be obtained by transmitting and receiving a radio ranging signal between the mobile station and the measurement target base station while continuing the constant velocity linear motion of the mobile station. And a second step of measuring the number of times.   The position measuring method according to claim 1, wherein an impulse signal is used as the wireless ranging signal.

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