Positioning device, positioning system, and control method for positioning device

Abstract

The present invention makes it possible for a system that comprises a reference station and an observation station to perform high-accuracy positioning in a short amount of time.　According to the present invention, a plurality of antennas convert electromagnetic waves from a satellite to high-frequency signals. A reception unit detects a carrier phase for each of the plurality of antennas on the basis of the high-frequency signals. A correction unit uses a prescribed reference time and vectors from the plurality of antennas to a prescribed reference position to correct each of the carrier phases. A synthesis unit synthesizes the corrected carrier phases.

Description

Positioning device, positioning system, and method for controlling a positioning device

[0001] This technology relates to positioning devices. More specifically, it concerns positioning devices for determining the position of observation stations, positioning systems, and control methods for positioning devices.

[0002] Conventionally, GNSS (Global Navigation Satellite System), exemplified by the US GPS (Global Positioning System), has been widely used in various devices for the purpose of obtaining current location and time. One of the challenges in GNSS positioning is the degradation of positioning accuracy due to multipath. Patent Document 1 proposes a method to suppress the effects of multipath errors on a target station by using GNSS signals and geometric positional relationships of multiple other observation stations. In this proposed method, the double difference of GNSS signals is calculated between the target station and multiple observation stations, and the average value of the deviation from the geometric positional relationship (double difference deviation) is obtained, making it possible to detect outliers due to multipath errors. In addition, high-precision positioning technology using carrier phase, such as RTK (Real-Time Kinematic)-GNSS, requires averaging in the time direction in order to solve integer ambiguity.

[0003] Japanese Patent Publication No. 2014-085204

[0004] Patent Document 1 attempts to improve positioning accuracy by suppressing multipath errors through the use of multiple observation stations. However, due to the influence of noise in the GNSS signal, the accuracy is limited to a few centimeters. Since the GNSS signals from multiple observation stations are uncorrelated with each other, white noise can be reduced by averaging the phases. However, due to the ambiguity problem of the carrier phase, it is necessary to take a double phase difference and average it, and this double phase difference has the problem of increasing the amount of data transmitted between multiple observation stations. For this reason, RTK-GNSS has been performing millimeter-level high-precision positioning by averaging in the time direction rather than in the spatial direction.

[0005] This technology was developed in light of these circumstances, and its purpose is to enable high-precision positioning in a short amount of time in a system that includes a base station and observation stations.

[0006] This technology was developed to solve the aforementioned problems, and its first aspect is a positioning device and control method comprising: multiple antennas that convert electromagnetic waves from a satellite into high-frequency signals; a receiving unit that detects the carrier phase for each of the multiple antennas based on the high-frequency signals; a correction unit that corrects each of the carrier phases using a predetermined reference time and a vector from the multiple antennas to a predetermined reference position; and a combining unit that combines each of the corrected carrier phases. This results in improved distance measurement accuracy.

[0007] Furthermore, in this first aspect, the system may further include a communication unit, the combining unit may combine each of the corrected carrier phases and output them as a first combined carrier phase, and the communication unit may transmit the first combined carrier phase. This results in high-precision positioning being performed on the server side.

[0008] Furthermore, in this first aspect, the system may further include a communication unit and a positioning unit, wherein the combining unit combines each of the corrected carrier phases and outputs it as a first combined carrier phase, the communication unit receives a second combined carrier phase, and the positioning unit generates position information based on the first combined carrier phase and the second combined carrier phase. This eliminates the need for a server.

[0009] Furthermore, in this first aspect, the positioning unit may include a dual phase difference calculation unit that calculates a dual phase difference from the first combined carrier phase and the second combined carrier phase, a baseline vector search unit that searches for a baseline vector based on the dual phase difference, and a position information generation unit that generates the position information from the baseline vector. This results in the position information being generated by the least squares method.

[0010] Furthermore, in this first aspect, the correction unit may include a time correction unit that corrects each of the carrier phases to the phase they would have if received at the reference time, and a position correction unit that corrects each of the carrier phases corrected by the time correction unit to the phase they would have had if received at the reference position using the vector. This results in the ability to combine the carrier phases.

[0011] Furthermore, in this first aspect, the receiving unit may include a mixer that mixes the high-frequency signal and a predetermined local signal to generate a common-mode signal and a quadrature signal, and a carrier phase detection unit that detects the carrier phase from the common-mode signal and the quadrature signal. This results in the detection of the carrier phase.

[0012] Furthermore, a second aspect of this technology is a first positioning device comprising: a plurality of first antennas that convert electromagnetic waves from a satellite into a first high-frequency signal; a first receiving unit that detects a first carrier phase for each of the plurality of first antennas based on the first high-frequency signal; a first correction unit that corrects each of the first carrier phases using a predetermined first reference time and a vector from the plurality of first antennas to a predetermined first reference position; and a first combining unit that combines each of the corrected first carrier phases and outputs it as a first combined carrier phase. The positioning system comprises a second positioning device which includes a plurality of second antennas that convert electromagnetic waves from a satellite into a second high-frequency signal, a second receiving unit that detects a second carrier phase for each of the plurality of second antennas based on the second high-frequency signal, a second correction unit that corrects each of the second carrier phases using a predetermined second reference time and a vector from the plurality of second antennas to a predetermined second reference position, and a second combining unit that combines each of the corrected second carrier phases and outputs it as a second combined carrier phase. This results in improved positioning accuracy.

[0013] Furthermore, in this second aspect, the system may further include a server that generates position information based on the first combined carrier phase and the second combined carrier phase. This results in the server performing high-precision positioning.

[0014] Furthermore, in this second aspect, the second positioning device may further include a positioning unit that generates position information based on the first combined carrier phase and the second combined carrier phase. This eliminates the need for a server.

[0015] Furthermore, a third aspect of this technology is a positioning system comprising: a first positioning device comprising: a plurality of first antennas that convert electromagnetic waves from a satellite into a first high-frequency signal; a first receiving unit that detects a first carrier phase for each of the plurality of first antennas based on the first high-frequency signal; a first correction unit that corrects each of the first carrier phases using a predetermined first reference time and a vector from the plurality of first antennas to a predetermined first reference position; and a first combining unit that combines each of the corrected first carrier phases and outputs it as a first combined carrier phase; and a second positioning device comprising: a second antenna that receives electromagnetic waves from a satellite and outputs a second high-frequency signal; and a second receiving unit that detects a second carrier phase based on the second high-frequency signal. This results in improved positioning accuracy.

[0016] This is a diagram showing an example configuration of a positioning system in the first embodiment of this technology. This is a block diagram showing an example configuration of a reference station in the first embodiment of this technology. This is a plan view showing an example of a GNSS antenna layout in the first embodiment of this technology. This is a block diagram showing an example configuration of a GNSS receiver in the first embodiment of this technology. This is a block diagram showing an example configuration of a correction unit in the first embodiment of this technology. This is a block diagram showing an example configuration of an observation station in the first embodiment of this technology. This is a block diagram showing an example of a server configuration in the first embodiment of this technology. This is a diagram showing an example of observation data in the first embodiment of this technology. This is a perspective view showing an example of antenna layout in the comparative example and the first embodiment of this technology, respectively. This is a graph showing an example of positioning results in the comparative example. This is a graph showing an example of positioning results in the first embodiment of this technology. This is a sequence diagram showing an example of the operation of the positioning system in the first embodiment of this technology. This is a block diagram showing an example configuration of an observation station in the second embodiment of this technology. This is a block diagram showing an example configuration of a positioning unit in the second embodiment of this technology. This is a plan view showing an example of a GNSS antenna layout in the third embodiment of this technology. This is a block diagram showing an example configuration of an observation station in the third embodiment of this technology.

[0017] The following describes the embodiments for implementing this technology. The description will proceed in the following order: 1. First embodiment (an example in which the carrier phase of each antenna is corrected and combined) 2. Second embodiment (an example in which the carrier phase of each antenna is corrected and combined, and the observation station performs positioning) 3. Third embodiment (an example in which only the reference station corrects and combines the carrier phase of each antenna)

[0018] <1. First Embodiment> [Example of Positioning System Configuration] Figure 1 shows an example of the configuration of a positioning system 120 in the first embodiment of the present technology. This positioning system 120 includes a base station 200, an observation station 300, and a server 400.

[0019] The reference station 200 is a fixed station whose location is known. This reference station 200 receives electromagnetic waves from multiple GNSS satellites, such as GNSS satellites 111 and 112, generates the data necessary for positioning the observation station 300, and transmits it to the server 400.

[0020] Observation station 300 is a mobile station whose location is unknown. For example, a small wireless terminal that a user can carry and move around can be used as observation station 300. Observation station 300 receives electromagnetic waves from multiple GNSS satellites such as GNSS satellites 111 and 112, generates the data necessary for positioning, and transmits it to server 400.

[0021] The server 400 receives data from the reference station 200 and the observation station 300, and generates location information indicating the location of the observation station 300 based on that data. The server 400 then transmits the generated location information to the observation station 300.

[0022] [Example of Base Station Configuration] Figure 2 is a block diagram showing an example configuration of a base station 200 in the first embodiment of this technology. This base station 200 includes GNSS antennas 211, 212, 213 and 214, a receiving unit 220, a correction unit 250, a combining unit 271, and a communication unit 272. The receiving unit 220 includes GNSS receivers 230, 221, 222 and 223.

[0023] The GNSS antenna 211 receives electromagnetic waves from GNSS satellites as high-frequency signals Rf Ａ１ This converts the signal into a high-frequency signal Rf and outputs it to the GNSS receiver 230. The GNSS antenna 212 receives electromagnetic waves from the GNSS satellite as a high-frequency signal Rf Ａ２ The signal is converted to a high-frequency signal Rf and output to the GNSS receiver 221. The GNSS antenna 213 receives electromagnetic waves from the GNSS satellite as a high-frequency signal Rf Ａ３ This converts the signal into a high-frequency signal Rf and outputs it to the GNSS receiver 222. The GNSS antenna 214 receives electromagnetic waves from the GNSS satellite as a high-frequency signal Rf Ａ４ This is converted and output to the GNSS receiver 223. These high-frequency signals are also called RF (Radio Frequency) signals.

[0024] The GNSS receiver 230 detects the carrier phase and the like for each GNSS satellite based on the high-frequency signal Rf. Ａ１ This GNSS receiver 230 generates observation data OBS(A1) including various data such as the carrier phase and navigation message NAV(A1), and supplies them to the correction unit 250.

[0025] The GNSS receiver 221 generates observation data OBS(A2) and navigation message NAV(A2) based on the high-frequency signal Rf, and supplies them to the correction unit 250. The GNSS receiver 222 generates observation data OBS(A3) and navigation message NAV(A3) based on the high-frequency signal Rf, and supplies them to the correction unit 250. The GNSS receiver 223 generates observation data OBS(A4) and navigation message NAV(A4) based on the high-frequency signal Rf, and supplies them to the correction unit 250. Ａ２ Ａ３ Ａ４

[0026] As described above, the receiving unit 220 detects the carrier phase for each GNSS satellite and each GNSS antenna based on the high-frequency signal. When there are 4 GNSS antennas and the number of tracked GNSS satellites is N (N is an integer), 4×N carrier phases are detected.

[0027] The correction unit 250 corrects each of the carrier phases using the reference time and the vector from the GNSS antenna to the known reference position A0. The correction unit 250 supplies the corrected carrier phases φ'' ｎ ｒ＿Ａ１ to φ'' ｎ ｒ＿Ａ４ to the synthesizing unit 271. Here, n is the number assigned to the GNSS satellite and is an integer from 1 to N. These carrier phases are collectively referred to as φ'' ｎ ｒ＿Ａｋ . k is the number assigned to the GNSS antenna and is an integer from 1 to 4.

[0028] The synthesizing unit 271 synthesizes the carrier phases φ'' output from the correction unit 250 ｎ ｒ＿ＡｋThis combines the following. The combining unit 271 combines four carrier phases for each GNSS satellite, for example, using the following formula.

[0029] In the above equation, tan －１ is the inverse function of the tangent function. sin is the sine function, and cos is the cosine function.

[0030] Also, φ ｎ Ａ０ teeth 、 This is the value after synthesis, and this value is called the "synthesized carrier phase". The synthesis unit 271 is the synthesized carrier phase φ ｎ Ａ０ This is supplied to the communications unit 272.

[0031] The communication unit 272 communicates the combined carrier phase φ via wired or wireless connection. ｎ Ａ０ This will be sent to server 400.

[0032] The reference station 200 is an example of the first positioning device described in the claims. The GNSS antennas 211, 212, 213, and 214 are examples of the first antennas described in the claims. The receiving unit 220 is an example of the first receiving unit described in the claims. The correction unit 250 is an example of the first correction unit described in the claims, and the combining unit 271 is an example of the first combining unit described in the claims.

[0033] [GNSS Antenna Layout] Figure 3 is a plan view showing an example of a GNSS antenna layout in the first embodiment of this technology. In the figure, a shows an example of the layout of GNSS antennas 211 to 214 of the reference station 200. In the figure, b shows an example of the layout of GNSS antennas 311 to 314 of the observation station 300.

[0034] As illustrated in figure a, the base station 200 has a plate 210 on which GNSS antennas 211 to 214 are arranged in a cross shape. The center position of these antennas is defined as the base position A0 of the base station 200. The base position A0 is known in positioning calculations, and its coordinates are stored in advance in a server 400 or the like. The distance D between the base position A0 and each of the GNSS antennas 211 to 214 is constant.

[0035] Furthermore, the vector from the GNSS antenna 211 to the reference position A0 is r Ａ１ The vector from the GNSS antenna 212 to the reference position A0 is r Ａ２ Let's assume that the vector from the GNSS antenna 213 to the reference position A0 is r. Ａ３ The vector from the GNSS antenna 214 to the reference position A0 is r Ａ４ Let's assume these vectors r Ａ１ kara r Ａ４ This is known and is pre-stored within the base station 200.

[0036] As illustrated in figure b, the observation station 300 has a plate 310 on which GNSS antennas 311 to 314 are arranged in a cross shape. The center position of these antennas is defined as the reference position B0 of the observation station 300. The reference position B0 is unknown in the positioning calculation and is the target of positioning.

[0037] Furthermore, the vector from the GNSS antenna 311 to the reference position B0 is r Ｂ１ The vector from the GNSS antenna 312 to the reference position B0 is r Ｂ２ Let's assume that the vector from the GNSS antenna 313 to the reference position B0 is r. Ｂ３ The vector from the GNSS antenna 314 to the reference position B0 is r Ｂ４ Let's assume these vectors r Ｂ１ kara r Ｂ４ This is known and is stored in advance within observation station 300.

[0038] The number and layout of GNSS antennas are not limited to those exemplified in figures a and b. While it is preferable to have the same number and layout of GNSS antennas at both the base station 200 and the observation station 300, this configuration is not required. The number of GNSS antennas or the layouts may differ between the base station 200 and the observation station 300.

[0039] [Example of GNSS receiver configuration] Figure 4 is a block diagram showing an example configuration of a GNSS receiver 230 in the first embodiment of this technology. This GNSS receiver 230 includes a bandpass filter 231, a local oscillator 232, a mixer 233, a Gold code generation unit 234, a despreader processing unit 235, a carrier phase detection unit 236, a code information decoding unit 237, a parameter calculation unit 238, and an interface 239. The configurations of GNSS receivers 221, 222, and 223 are the same as those of GNSS receiver 230.

[0040] The bandpass filter 231 receives the high-frequency signal Rf from the GNSS antenna 211. Ａ１ This filter allows a specific frequency band to pass through and is supplied to the mixer 233. This filter extracts a signal centered around the carrier frequency of the satellite radio waves (e.g., 1.57 gigahertz). For example, a SAW (Surface Acoustic Wave) filter is used as the bandpass filter 231.

[0041] The local oscillator 232 generates a predetermined local signal and supplies it to the mixer 233. For example, a crystal oscillator is used as the local oscillator 232.

[0042] Mixer 233 receives the high-frequency signal Rf from the bandpass filter 231. Ａ１ The local signal is mixed with the I (In-phase) signal and the Q (Quadrature) signal to generate an in-phase signal and a quadrature signal. These I and Q signals are supplied to the despreading processing unit 235 and the carrier phase detection unit 236. A quadrature phase modulator, for example, is used as the mixer 233.

[0043] The carrier phase detection unit 236 determines the carrier phase φ based on the I signal and the Q signal. ｎ ｒ＿Ａ１ It detects this and supplies it to interface 239.

[0044] The Gold code generation unit 234 generates a pseudo-random number sequence corresponding to the Gold code and supplies it to the despreading processing unit 235.

[0045] The despreading processing unit 235 performs a despreading process by multiplying the pseudo-random number sequence from the Gold code generation unit 234 by the I signal and the Q signal, and then integrating the result. This recovers the signals superimposed on the I signal and the Q signal. The despreading processing unit 235 then supplies the recovered code information to the parameter calculation unit 238 and the code information decoding unit 237.

[0046] The code information decoding unit 237 decodes the code information to obtain the navigation message NAV(A1). This navigation message NAV(A1) includes the orbital information of the GNSS satellite and the time correction data of the GNSS satellite.

[0047] The parameter calculation unit 238 calculates various parameters, such as reception timing, using code information. This parameter calculation unit 238 obtains the positions and transmission timings of four or more GNSS satellites from the code information and calculates the reception timing from them.

[0048] Furthermore, the parameter calculation unit 238 calculates a pseudo-distance for each GNSS satellite, which is the difference between the reception timing and the transmission timing multiplied by the speed of light. The parameter calculation unit 238 also calculates the approximate distance to each GNSS satellite by single-point positioning using code information. The parameter calculation unit 238 also calculates a direction vector from the position of the GNSS receiver, obtained by single-point positioning, to the position of the satellite for each GNSS satellite. The parameter calculation unit 238 also calculates the difference between the satellite's transmission frequency and reception frequency as a Doppler shift. The parameter calculation unit 238 supplies the calculated parameters to the interface 239.

[0049] Interface 239 generates observation data OBS(A1) and outputs it to the correction unit 250 along with the navigation message NAV(A1). This data is converted, for example, into a UART (Universal Asynchronous Receiver Transmitter) signal. The observation data OBS(A1) includes parameters such as reception timing calculated by the parameter calculation unit 238 and the carrier phase detected by the carrier phase detection unit 236.

[0050] [Example of Correction Unit Configuration] Figure 5 is a block diagram showing an example of the configuration of the correction unit 250 in the first embodiment of this technology. This correction unit 250 comprises time correction units 251, 252, 253 and 254, position correction units 255, 256, 257 and 258, a system time setting unit 259, and a vector storage unit 260.

[0051] The reception timings of the GNSS receivers 230, 221, 222, and 223 are different, and their positions are also different. Therefore, the carrier phase before correction cannot be used for the averaging process described later. Thus, the correction unit 250 corrects the carrier phase to match the phase received at the reference time and reference position A0.

[0052] The system time setting unit 259 sets the system time Ts as a reference time based on the reception timing of each GNSS receiver and supplies it to the time correction units 251, 252, 253, and 254. The reception timing in the observation data OBS(Ak) is input to this system time setting unit 259. The system time setting unit 259 sets a predetermined time near those reception timings as the system time Ts. For example, let's assume there are only two GNSS receivers, and the reception timing of one of them is "6:14:59.966" and the reception timing of the other is "6:14:59.964". In this case, a round time such as "6:15:00" will be set as the system time Ts.

[0053] The time correction unit 251 adjusts the carrier wave phase φ ｎ ｒ＿Ａ１This corrects the phase to that of the time received at the reference system time Ts. The observation data OBS(A1) and navigation message NAV(A1) from the GNSS receiver 230 are input to this time correction unit 251.

[0054] The time correction unit 251 performs correction using, for example, the following formula, and the corrected carrier phase φ' ｎ ｒ＿Ａ１ The calculation is performed and supplied to the position correction unit 255 along with the observation data OBS(A1). If the number of GNSS satellites is N, then N φ' values ​​are calculated. ｎ ｒ＿Ａ１ The following calculation is performed: σ(n) = Ts - T ｒ＿Ａ１ -{Range(n)-PR(n)} / Cv -SDelay(n) ...Formula 2 φ' ｎ ｒ＿Ａ１ = φ ｎ ｒ＿Ａ１ -σ(n)Dp(n) ...Formula 3

[0055] In equation 2, T ｒ＿Ａ１ This indicates the reception timing of the GNSS receiver 230. Range(n) indicates the approximate distance from the nth (where n is an integer from 1 to N)th GNSS satellite to the GNSS receiver 230. PR(n) indicates the pseudo-distance to the nth GNSS satellite. Cv indicates the speed of light. SDelay(n) indicates the time delay of the nth GNSS satellite. In equation 3, Dp(n) indicates the Doppler shift of the nth GNSS satellite. T ｒ＿Ａ１ Range(n), PR(n), and Dp(n) are included in the observation data OBS(A1). SDeay(n) is included in the navigation message NAV(A1).

[0056] The time correction unit 252 adjusts the carrier wave phase φ ｎ ｒ＿Ａ２ This corrects the phase to that of the signal received at system time Ts. The observation data OBS(A2) and navigation message NAV(A2) from the GNSS receiver 221 are input to this time correction unit 252. The time correction unit 252 performs the same calculation as the time correction unit 251 to correct the carrier phase φ'. ｎ ｒ＿Ａ２This is calculated and supplied to the position correction unit 256 along with the observation data OBS(A2).

[0057] The time correction unit 253 adjusts the carrier wave phase φ ｎ ｒ＿Ａ３ This corrects the phase to that of the signal received at system time Ts. The observation data OBS(A3) and navigation message NAV(A3) from the GNSS receiver 222 are input to this time correction unit 253. The time correction unit 253 performs the same calculation as the time correction unit 251 to correct the carrier phase φ'. ｎ ｒ＿Ａ３ This is calculated and supplied to the position correction unit 257 along with the observation data OBS(A3).

[0058] The time correction unit 254 adjusts the carrier wave phase φ ｎ ｒ＿Ａ４ This corrects the phase to that of the signal received at system time Ts. Observation data OBS(A4) and navigation message NAV(A4) from the GNSS receiver 223 are input to this time correction unit 254. The time correction unit 254 performs the same calculation as the time correction unit 251 to correct the carrier phase φ'. ｎ ｒ＿Ａ４ This is calculated and supplied to the position correction unit 258 along with the observation data OBS(A4).

[0059] The vector storage unit 260 stores a vector r from the four GNSS antennas to the reference position A0. Ａ１ ,r Ａ２ ,r Ａ３ and r Ａ４ It stores the vector r. Ａ１ The position correction unit 255 reads out the vector r Ａ２ The vector r is read out by the position correction unit 256. Ａ３ The position correction unit 257 reads out the vector r Ａ４ This is read out by the position correction unit 258.

[0060] The position correction unit 255 generates a vector r to the reference position A0. Ａ１ Using the carrier phase φ' ｎ ｒ＿Ａ１ This corrects the phase to that of the carrier wave received at the reference position A0. This position correction unit 255 corrects the carrier wave phase φ'' after correction using, for example, the following formula.ｎ ｒ＿Ａ１ are calculated and supplied to the combining unit 271. When the number of GNSS satellites is N, N φ'' ｎ ｒ＿Ａ１ are calculated. φ'' ｎ ｒ＿Ａ１ = φ' ｎ ｒ＿Ａ１ + I ｎ ・r Ａ１ ... Equation 4 In the above equation, I ｎ indicates the direction vector to the nth GNSS satellite. This I ｎ is included in the observation data OBS(A1).

[0061] The position correction unit 256 uses the vector r Ａ２ to the reference position A0 to correct the carrier phase φ' ｎ ｒ＿Ａ２ to the phase when received at the reference position A0. This position correction unit 256 obtains the carrier phase φ'' ｎ ｒ＿Ａ２ by the same operation as the position correction unit 255 and supplies it to the combining unit 271.

[0062] The position correction unit 257 uses the vector r Ａ３ to the reference position A0 to correct the carrier phase φ' ｎ ｒ＿Ａ３ to the phase when received at the reference position A0. This position correction unit 257 obtains the carrier phase φ'' ｎ ｒ＿Ａ３ by the same operation as the position correction unit 255 and supplies it to the combining unit 271.

[0063] The position correction unit 258 uses the vector r Ａ４ to the reference position A0 to correct the carrier phase φ' ｎ ｒ＿Ａ４ to the phase when received at the reference position A0. This position correction unit 258 obtains the carrier phase φ'' ｎ ｒ＿Ａ４ by the same operation as the position correction unit 255 and supplies it to the combining unit 271.

[0064] [Example of Observation Station Configuration] Figure 6 is a block diagram showing an example configuration of an observation station 300 in the first embodiment of this technology. This observation station 300 comprises GNSS antennas 311, 312, 313 and 314, a receiving unit 320, a correction unit 350, a combining unit 371, and a communication unit 372. The receiving unit 320 comprises GNSS receivers 321, 322, 323 and 324.

[0065] The GNSS antenna 311 receives electromagnetic waves from GNSS satellites as high-frequency signals Rf Ｂ１ The signal is converted to a high-frequency signal Rf and output to the GNSS receiver 321. The GNSS antenna 312 receives electromagnetic waves from the GNSS satellite as a high-frequency signal Rf. Ｂ２ The signal is converted to a high-frequency signal Rf and output to the GNSS receiver 322. The GNSS antenna 313 receives electromagnetic waves from the GNSS satellite as a high-frequency signal Rf Ｂ３ The signal is converted to a high-frequency signal Rf and output to the GNSS receiver 323. The GNSS antenna 314 receives electromagnetic waves from the GNSS satellite as a high-frequency signal Rf. Ｂ４ It is converted to and output to the GNSS receiver 324.

[0066] The GNSS receiver 321 receives a high-frequency signal Rf Ｂ１ Based on this, observation data OBS(B1) and navigation message NAV(B1) are generated and supplied to the correction unit 350. The GNSS receiver 322 receives the high-frequency signal Rf Ｂ２ Based on this, observation data OBS(B2) and navigation message NAV(B2) are generated and supplied to the correction unit 350. The GNSS receiver 323 receives the high-frequency signal Rf Ｂ３ Based on this, observation data OBS(B3) and navigation message NAV(B3) are generated and supplied to the correction unit 350. The GNSS receiver 324 receives the high-frequency signal Rf Ｂ４ Based on this, observation data OBS(B4) and navigation message NAV(B4) are generated and supplied to the correction unit 350. The configurations of the GNSS receivers 321, 322, 323, and 324 are the same as those of the GNSS receiver 230 in the base station 200.

[0067] The correction unit 350 corrects the carrier phase using the reference time and a vector from each GNSS antenna to an unknown reference position B0. The correction unit 350 then corrects the carrier phase φ''. ｎ ｒ＿Ｂ１ from φ'' ｎ ｒ＿Ｂ４ This is supplied to the synthesis unit 371.

[0068] However, in the correction unit 350, the following equation is used instead of equations 2 to 4: σ(n) = Ts - T ｒ＿Ｂ１ -{Range(n)-PR(n)} / Cv -SDelay(n) ...Formula 5 φ' ｎ ｒ＿Ｂ１ = φ ｎ ｒ＿Ｂ１ -σ(n)Dp(n) ...Formula 6 φ'' ｎ ｒ＿Ｂ１ = φ' ｎ ｒ＿Ｂ１ +I ｎ r Ｂ１ ...Formula 7

[0069] The combining unit 371 receives the carrier wave phase φ'' output from the correction unit 250. ｎ ｒ＿Ｂｋ This combines the following. The combining unit 371 combines four carrier phases for each GNSS satellite, for example, using the following formula, to form the combined carrier phase φ ｎ Ｂ０ This is supplied to the communications unit 272.

[0070]

[0071] The communication unit 372 wirelessly transmits the combined carrier phase φ ｎ Ｂ０ This is transmitted to the server 400. The communication unit 372 also receives location information of the reference position B0 from the server 400.

[0072] The observation station 300 is an example of the second positioning device described in the claims. The GNSS antennas 311, 312, 313, and 314 are examples of the second antenna described in the claims. The receiving unit 320 is an example of the second receiving unit described in the claims. The correction unit 350 is an example of the second correction unit described in the claims, and the combining unit 371 is an example of the second combining unit described in the claims.

[0073] [Example of Server Configuration] Figure 7 is a block diagram showing an example configuration of a server 400 in the first embodiment of this technology. This server 400 includes a communication unit 410, a dual phase difference calculation unit 420, an optimal baseline vector search unit 430, and a position information generation unit 440.

[0074] The communication unit 410 transmits and receives data between the base station 200 and the observation station 300 by wire or wireless connection. The communication unit 410 receives the combined carrier phase φ from the base station 200 and the observation station 300. ｎ Ａ０ and φ ｎ Ｂ０ The signal is received and supplied to the dual phase difference calculation unit 420.

[0075] The dual phase difference calculation unit 420 calculates the combined carrier phase φ ｎ Ａ０ and φ ｎ Ｂ０ Therefore, the double phase difference Δφ ｎ This unit calculates the double phase difference Δφ. ｎ This is supplied to the optimal baseline vector search unit 430.

[0076] The optimal baseline vector search unit 430 uses a dual phase difference Δφ ｎ Based on this, the optimal baseline vector P from reference position A0 to reference position B0 is searched. For example, the baseline vector P is searched using the FCP (Fractional Carrier Phase) method, which uses only the fractional part of the carrier phase. The optimal baseline vector search unit 430 supplies the obtained baseline vector P to the position information generation unit 440.

[0077] The location information generation unit 440 determines an unknown reference position B0 from a known reference position A0 and a baseline vector P. The server 400 acquires and stores the reference position A0 in advance before positioning. The location information generation unit 440 generates location information indicating the determined reference position B0 and supplies it to the communication unit 410. The communication unit 410 transmits the location information to the observation station 300.

[0078] As described above, the positioning method that determines the position of a moving observation station 300 from dual phase difference is called the kinematic method. Furthermore, the kinematic method performed in real time is called RTK.

[0079] Figure 8 shows an example of observation data in the first embodiment of this technology. In the figure, a shows an example of observation data OBS(Ak) from a GNSS receiver in the reference station 200. In the figure, b shows an example of observation data OBS(Bk) from a GNSS receiver in the observation station 300.

[0080] As illustrated in figure a, the observation data OBS(Ak) is received at the reception timing T of the kth GNSS receiver. ｒ＿Ａｋ Includes.

[0081] Furthermore, "G02" and "G04" indicate the identification information of the GNSS satellite. The observation data OBS(Ak) for each GNSS satellite includes the pseudo-distance PR(n) and carrier phase φ ｎ ｒ＿Ａｋ This includes data such as the Doppler shift Dp(n).

[0082] As illustrated in figure b, the observation data OBS(Bk) is received at the reception timing T of the kth GNSS receiver. ｒ＿Ｂｋ This includes, for each GNSS satellite, pseudo-distance PR(n), carrier phase φ ｎ ｒ＿Ｂｋ This includes data such as the Doppler shift Dp(n).

[0083] Each of the reference station 200 and the observation station 300 performs the corrections illustrated in Figure 5 using the data described above.

[0084] Here, as illustrated in Figure 9a, we consider a configuration in which only one GNSS antenna is placed in each of the base station 200 and the observation station 300 as a comparative example. In the comparative example, the GNSS antenna 211 is placed on the plate 210 inside the base station 200, and the GNSS antenna 311 is placed on the plate 310 inside the observation station 300.

[0085] In the figure, b is a perspective view showing an example of the antenna layout in the first embodiment. In the first embodiment, GNSS antennas 211, 212, 213 and 214 are arranged on plate 210 in base station 200, and GNSS antennas 311, 312, 313 and 314 are arranged on plate 310 in observation station 300.

[0086] In the figure, we conducted an experiment to determine the baseline vector P at points a and b, and to position the reference location B0.

[0087] Figure 10 is a graph showing an example of positioning results in a comparative example. The vertical axis in this figure represents the distance in the north-south, east-west, and up-down directions, and the horizontal axis represents the time when the positioning was performed.

[0088] Figure 11 is a graph showing an example of the positioning results in the first embodiment. The vertical axis in the figure represents the distance in the north-south, east-west, and up-down directions, and the horizontal axis represents the time when the positioning was performed.

[0089] As illustrated in Figure 10, the comparative example exhibits significant variation in positioning results. In contrast, the first embodiment significantly reduces spatial noise by combining (in other words, averaging) the carrier phases of each antenna. As a result, as illustrated in Figure 11, the variation in positioning results is reduced to half that of the comparative example.

[0090] In the comparative example, spatial noise can be reduced by receiving signals multiple times and performing temporal averaging. However, in that case, measurements would need to be taken for more than one hour, which is not practical when setting up a mobile observation station 300.

[0091] [Example of Positioning System Operation] Figure 12 is a sequence diagram showing an example of the operation of the positioning system 120 in the first embodiment of this technology. The base station 200 receives electromagnetic waves from GNSS satellites with multiple GNSS antennas (step S901). The observation station 300 receives electromagnetic waves from GNSS satellites with multiple GNSS antennas (step S902).

[0092] Then, the reference station 200 determines the carrier phase for each GNSS antenna and each GNSS satellite, and corrects these phases based on the reference time and reference position A0 (step S903). The observation station 300 determines the carrier phase for each GNSS antenna and each GNSS satellite, and corrects these phases based on the reference time and reference position B0 (step S904).

[0093] The reference station 200 combines each of the corrected carrier phases (step S905), and the observation station 300 combines each of the corrected carrier phases (step S906). Then, the reference station 200 transmits the combined carrier phase to the server 400 (step S907), and the observation station 300 transmits the combined carrier phase to the server 400 (step S908).

[0094] The server 400 determines the reference position B0 of the observation station 300 from the combined carrier phases (step S909) and transmits the position information of the reference position B0 to the observation station 300 (step S910).

[0095] As described above, according to the first embodiment of this technology, multiple antennas are provided at each of the reference station 200 and the observation station 300, and at each station, the carrier phase of each antenna is corrected and combined based on the reference time and reference position. As a result, the server 400 can perform high-precision positioning in a short time using the combined carrier phases.

[0096] <2. Second Embodiment> In the first embodiment described above, the server 400 performed the positioning, but the configuration is not limited to this. The positioning system 120 in this second embodiment differs from the first embodiment in that the observation station 300 performs the positioning.

[0097] Figure 13 is a block diagram showing an example configuration of an observation station 300 in a second embodiment of the present technology. The observation station 300 in this second embodiment differs from the first embodiment in that it further includes a positioning unit 380.

[0098] Furthermore, in the second embodiment, the communication unit 372 receives the combined carrier phase φ from the reference station 200. ｎ Ａ０ The signal is received and supplied to the positioning unit 380. The combining unit 371 combines the carrier phase φ ｎ Ｂ０ This is supplied to the positioning unit 380.

[0099] The positioning unit 380 controls the combined carrier phase φ ｎ Ａ０ and φ ｎ Ｂ０ This generates and outputs position information for reference position B based on the given data.

[0100] Figure 14 is a block diagram showing an example configuration of a positioning unit 380 in a second embodiment of the present technology. This positioning unit 380 includes a dual phase difference calculation unit 381, an optimal baseline vector search unit 382, ​​and a position information generation unit 383. The processing contents of the dual phase difference calculation unit 381, the optimal baseline vector search unit 382, ​​and the position information generation unit 383 are the same as those of the dual phase difference calculation unit 420, the optimal baseline vector search unit 430, and the position information generation unit 440 in the first embodiment. The optimal baseline vector search unit 382 is an example of a baseline vector search unit described in the claims.

[0101] As illustrated in Figures 13 and 14, since the observation station 300 itself performs positioning and generates location information, communication between the observation station and the server 400 becomes unnecessary.

[0102] Thus, according to the second embodiment of this technology, since the observation station 300 generates the location information, communication between the observation station and the server 400 can be reduced.

[0103] <3. Third Embodiment> In the first embodiment described above, multiple GNSS antennas were placed at both the base station 200 and the observation station 300, but the number of antennas can also be reduced. The positioning system 120 in this third embodiment differs from the first embodiment in that only one GNSS antenna is placed at the observation station 300.

[0104] Figure 15 is a plan view showing an example of a GNSS antenna layout in a third embodiment of the present technology. In the figure, a shows an example of the layout of GNSS antennas 211 to 214 of the reference station 200. In the figure, b shows an example of the layout of GNSS antennas 311 to 314 of the observation station 300.

[0105] As illustrated in figure a, in the third embodiment, the plate 210 of the reference station 200 has multiple GNSS antennas such as GNSS antennas 211, 212, 213, and 214 arranged on it, similar to the first embodiment.

[0106] On the other hand, as illustrated in figure b, only the GNSS antenna 311 is placed on the plate 310 of the observation station 300 in the third embodiment.

[0107] Figure 16 is a block diagram showing one example configuration of an observation station 300 in a third embodiment of the present technology. The observation station 300 in this third embodiment includes a GNSS antenna 311, a GNSS receiver 321, and a communication unit 372.

[0108] The GNSS antenna 311 receives electromagnetic waves from GNSS satellites as high-frequency signals Rf Ｂ１ It is converted to and output to the GNSS receiver 321. The GNSS receiver 321 receives the high-frequency signal Rf Ｂ１ Based on this, the carrier phase φ ｎ ｒ＿Ｂ１ It detects this and supplies it to the communication unit 372.

[0109] Server 400 receives the combined carrier phase φ from the base station 200. ｎ Ａ０ And the carrier phase φ from observation station 300 ｎ ｒ＿Ｂ１ Location information is generated based on this.

[0110] As illustrated in Figures 15 and 16, by using only one GNSS antenna at observation station 300, the number of GNSS receivers 322, 323, and 324, as well as the correction unit 350 and the combining unit 371, can be reduced at observation station 300.

[0111] Alternatively, the base station 200 can be equipped with only one GNSS antenna, while the observation station 300 can be equipped with multiple GNSS antennas.

[0112] Furthermore, the second embodiment, in which positioning is performed at the observation station 300, can also be applied to the third embodiment.

[0113] Thus, according to the third embodiment of this technology, since only one GNSS antenna is installed in the observation station 300, the GNSS receiver within the observation station 300, as well as the correction and synthesis processes, can be reduced.

[0114] The embodiments described above are merely examples of how to realize this technology, and there is a corresponding relationship between the matters in the embodiments and the inventive features in the claims. Similarly, there is a corresponding relationship between the inventive features in the claims and the matters in the embodiments of this technology that bear the same name. However, this technology is not limited to the embodiments and can be realized by making various modifications to the embodiments without departing from the gist of the technology.

[0115] The effects described herein are merely illustrative and not limited to those described herein, and other effects may also occur.

[0116] Furthermore, this technology can also be configured as follows: (1) A positioning device comprising: a plurality of antennas that convert electromagnetic waves from a satellite into high-frequency signals; a receiving unit that detects the carrier phase for each of the plurality of antennas based on the high-frequency signals; a correction unit that corrects each of the carrier phases using a predetermined reference time and a vector from the plurality of antennas to a predetermined reference position; and a combining unit that combines each of the corrected carrier phases. (2) The positioning device according to (1), further comprising a communication unit, wherein the combining unit combines each of the corrected carrier phases and outputs it as a first combined carrier phase, and the communication unit transmits the first combined carrier phase. (3) The positioning device according to (1), further comprising a communication unit and a positioning unit, wherein the combining unit combines each of the corrected carrier phases and outputs it as a first combined carrier phase, the communication unit receives a second combined carrier phase, and the positioning unit generates position information based on the first combined carrier phase and the second combined carrier phase. (4) The positioning device according to (3), wherein the positioning unit comprises a double phase difference calculation unit that calculates a double phase difference from the first combined carrier phase and the second combined carrier phase, a baseline vector search unit that searches for a baseline vector based on the double phase difference, and a position information generation unit that generates the position information from the baseline vector. (5) The positioning device according to any one of (1) to (4), wherein the correction unit comprises a time correction unit that corrects each of the carrier phases to the phase when received at the reference time, and a position correction unit that corrects each of the carrier phases corrected by the time correction unit to the phase when received at the reference position using the vector. (6) The positioning device according to any one of (1) to (5), wherein the receiving unit comprises a mixer that mixes the high-frequency signal and a predetermined local signal to generate an in-phase signal and an orthogonal signal, and a carrier phase detection unit that detects the carrier phase from the in-phase signal and the orthogonal signal.(7) A positioning device comprising: a first positioning device comprising: a plurality of first antennas that convert electromagnetic waves from a satellite into a first high-frequency signal; a first receiving unit that detects a first carrier phase for each of the plurality of first antennas based on the first high-frequency signal; a first correction unit that corrects each of the first carrier phases using a predetermined first reference time and a vector from the plurality of first antennas to a predetermined first reference position; and a first combining unit that combines each of the corrected first carrier phases and outputs it as a first combined carrier phase; and a second positioning device comprising: a plurality of second antennas that convert electromagnetic waves from a satellite into a second high-frequency signal; a second receiving unit that detects a second carrier phase for each of the plurality of second antennas based on the second high-frequency signal; a second correction unit that corrects each of the second carrier phases using a predetermined second reference time and a vector from the plurality of second antennas to a predetermined second reference position; and a second combining unit that combines each of the corrected second carrier phases and outputs it as a second combined carrier phase. (8) The positioning system according to (7), further comprising a server that generates position information based on the first combined carrier phase and the second combined carrier phase. (9) The positioning system according to (7), further comprising a second positioning device that generates position information based on the first combined carrier phase and the second combined carrier phase. (10) A positioning system comprising: a first positioning device comprising: a plurality of first antennas that convert electromagnetic waves from a satellite into a first high-frequency signal; a first receiving unit that detects a first carrier phase for each of the plurality of first antennas based on the first high-frequency signal; a first correction unit that corrects each of the first carrier phases using a predetermined first reference time and a vector from the plurality of first antennas to a predetermined first reference position; and a first combining unit that combines each of the corrected first carrier phases and outputs it as a first combined carrier phase; and a second positioning device comprising: a second antenna that receives electromagnetic waves from a satellite and outputs a second high-frequency signal; and a second receiving unit that detects a second carrier phase based on the second high-frequency signal.(11) A control method for a positioning device comprising: a receiving procedure for detecting the carrier phase based on the high-frequency signal for each of a plurality of antennas that convert electromagnetic waves from a satellite into a high-frequency signal; a correction procedure for correcting each of the carrier phases using a predetermined reference time and a vector from the plurality of antennas to a predetermined reference position; and a synthesis procedure for synthesizing each of the corrected carrier phases.

[0117] 111, 112 GNSS satellite 120 Positioning system 200 Reference station 210, 310 Plate 211, 212, 213, 214, 311, 312, 313, 314 GNSS antenna 220, 320 Receiving unit 221, 222, 223, 230, 321, 322, 323, 324 GNSS receiver 231 Bandpass filter 232 Local oscillator 233 Mixer 234 Gold code generation unit 235 Despreader processing unit 236 Carrier phase detection unit 237 Code information decoding unit 238 Parameter calculation unit 239 Interface 250, 350 Correction unit 251, 252, 253, 254 Time correction unit 255, 256, 257, 258 Position correction unit 259 System time setting unit 260 Vector storage unit 271, 371 Synthesis unit 272, 372, 410 Communication unit 300 Observation station 380 Positioning unit 381, 420 Dual phase difference calculation unit 382, ​​430 Optimal baseline vector search unit 383, 440 Position information generation unit 400 Server

Claims

1. A positioning device comprising: a plurality of antennas that convert electromagnetic waves from a satellite into high-frequency signals; a receiving unit that detects the carrier phase for each of the plurality of antennas based on the high-frequency signals; a correction unit that corrects each of the carrier phases using a predetermined reference time and a vector from the plurality of antennas to a predetermined reference position; and a combining unit that combines each of the corrected carrier phases.

2. The positioning device according to claim 1, further comprising a communication unit, wherein the combining unit combines each of the corrected carrier phases and outputs them as a first combined carrier phase, and the communication unit transmits the first combined carrier phase.

3. The positioning device according to claim 1, further comprising a communication unit and a positioning unit, wherein the combining unit combines each of the corrected carrier phases and outputs it as a first combined carrier phase, the communication unit receives a second combined carrier phase, and the positioning unit generates position information based on the first combined carrier phase and the second combined carrier phase.

4. The positioning device according to claim 3, comprising: a dual phase difference calculation unit that calculates a dual phase difference from the first combined carrier phase and the second combined carrier phase; a baseline vector search unit that searches for a baseline vector based on the dual phase difference; and a position information generation unit that generates the position information from the baseline vector.

5. The positioning device according to claim 1, wherein the correction unit comprises a time correction unit that corrects each of the carrier phases to the phase when received at the reference time, and a position correction unit that corrects each of the carrier phases corrected by the time correction unit to the phase when received at the reference position using the vector.

6. The positioning device according to claim 1, wherein the receiving unit comprises a mixer that mixes the high-frequency signal and a predetermined local signal to generate an in-phase signal and a quadrature signal, and a carrier phase detection unit that detects the carrier phase from the in-phase signal and the quadrature signal.

7. A positioning system comprising: a first positioning device comprising: a plurality of first antennas that convert electromagnetic waves from a satellite into a first high-frequency signal; a first receiving unit that detects a first carrier phase for each of the plurality of first antennas based on the first high-frequency signal; a first correction unit that corrects each of the first carrier phases using a predetermined first reference time and a vector from the plurality of first antennas to a predetermined first reference position; and a first combining unit that combines each of the corrected first carrier phases and outputs it as a first combined carrier phase; and a second positioning device comprising: a plurality of second antennas that convert electromagnetic waves from a satellite into a second high-frequency signal; a second receiving unit that detects a second carrier phase for each of the plurality of second antennas based on the second high-frequency signal; a second correction unit that corrects each of the second carrier phases using a predetermined second reference time and a vector from the plurality of second antennas to a predetermined second reference position; and a second combining unit that combines each of the corrected second carrier phases and outputs it as a second combined carrier phase.

8. The positioning system according to claim 7, further comprising a server that generates position information based on the first combined carrier phase and the second combined carrier phase.

9. The positioning system according to claim 7, further comprising a positioning unit that generates position information based on the first combined carrier phase and the second combined carrier phase, the second positioning device.

10. A positioning system comprising: a first positioning device comprising: a plurality of first antennas that convert electromagnetic waves from a satellite into a first high-frequency signal; a first receiving unit that detects a first carrier phase for each of the plurality of first antennas based on the first high-frequency signal; a first correction unit that corrects each of the first carrier phases using a predetermined first reference time and a vector from the plurality of first antennas to a predetermined first reference position; and a first combining unit that combines each of the corrected first carrier phases and outputs it as a first combined carrier phase; and a second positioning device comprising: a second antenna that receives electromagnetic waves from a satellite and outputs a second high-frequency signal; and a second receiving unit that detects a second carrier phase based on the second high-frequency signal.

11. A control method for a positioning device comprising: a receiving procedure for detecting the carrier phase based on the high-frequency signal for each of a plurality of antennas that convert electromagnetic waves from a satellite into a high-frequency signal; a correction procedure for correcting each of the carrier phases using a predetermined reference time and a vector from the plurality of antennas to a predetermined reference position; and a synthesis procedure for synthesizing each of the corrected carrier phases.

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