JP2007010550A - Positioning device and positioning method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein position jump can be prevented by taking a weighted average of a moving velocity of a receiving point and a moving range determined on the basis of the variation of the positioned position by a positioning means, but an extra delay time occurs. <P>SOLUTION: The GPS positioning device 10 comprises a plurality of range measuring sections 14 and a positioning calculating section 21. The range measuring sections 14 have a main part for calculating a range to a GPS satellite and a sub part for providing auxiliary data to the main part. The main part comprises a GPS satellite identification section 42, a following interruption detecting section 46, a navigation data demodulating section 48, a track memory 52, a satellite position calculating section 54, a code false range calculating section 56, an offset estimating section 58, and a corrected false range calculating section 70. The sub part comprises a satellite transmission time calculating section 50, a carrier integration section 62, a carrier integration reset section 68, a carrier integration memory 64, a carrier estimating section 60, a moving velocity reporting apparatus 22, and a range measurement control section 44. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a positioning device that performs positioning by receiving a signal transmitted by a satellite.

  The satellite positioning system (GPS) receives signals transmitted from a plurality of satellites and performs positioning calculation based on the orbit information of each satellite and the pseudo distance to each satellite from the information included in the received signal. There are two types of positioning, and there are two types: single positioning that determines the absolute position of the receiving point alone and relative positioning that determines the relative position of the other point with respect to the reference point whose position has already been determined. Independent positioning is used to determine the position of a moving object that is stationary or moving relative to the Earth, and relative positioning is used to determine the precise position of a stationary point.

  In particular, in the case of a mobile object, a GPS satellite used for positioning may enter a building or some object, and radio waves from the GPS satellite may be interrupted. In addition, when radio waves from GPS satellites are reflected by building streets or some obstacles and received by multiple paths, multipath occurs and positioning results change discontinuously, so-called position jumps occur and accurate positioning occurs. There is a problem that it becomes impossible.

  In order to solve such a problem, as shown in Patent Document 1, a technique for smoothly outputting a change in positioning result associated with movement of a reception point, or as measured by a GPS code as disclosed in Patent Document 2. Techniques relating to the smoothing method are disclosed.

JP 2000-193732 A Japanese Patent No. 3455266

  In the technique disclosed in Patent Document 1, the position jump to the positioning position is performed by weighted averaging of the moving speed of the receiving point based on the carrier Doppler shift frequency and the moving distance obtained from the change of the positioning position by the positioning means. Even if this occurs, it can be reduced by the weight of the moving distance obtained from the moving speed.

  Similarly, the technique disclosed in Patent Document 2 is a technique for smoothing a GPS pseudo code signal with a carrier signal in a relatively long period to reduce multipaths and other errors. There is a problem that time is generated.

  In addition, as described above, the GPS signal is interrupted by some obstacle, so that the moving speed of the receiving point based on the Doppler shift frequency becomes indefinite and initialization by reset is necessary.

  For this reason, even after tracking again, it takes time until a sufficiently smoothed value is obtained. During this time, the effect of the error due to multipath becomes a pseudorange that cannot be sufficiently suppressed, and the satellite is positioned. In the positioning calculation result used for, an error due to multipath occurs.

  In order to solve the above problems, a positioning apparatus according to the present invention includes a receiver that receives signals from a plurality of satellites, a code pseudorange used for positioning from the signals received by the receiver, and a carrier Doppler. A positioning device that detects a frequency and obtains a position of a receiver mounted on a mobile body, a pseudo-range calculation unit that calculates a pseudo-range from the satellite to the receiver, and a carrier Doppler frequency. Carrier accumulating means for accumulating, moving speed calculating means for calculating the moving speed of the receiver from the carrier Doppler frequency, and performing reverse calculation of the positioning calculation using the moving speed of the receiver when the satellite tracking is interrupted, And Doppler frequency estimation means for estimating the Doppler frequency of the carrier of the satellite from the moving speed, and carrier tracking means interrupts tracking of the satellite Characterized by integrating the estimated Doppler frequency when the.

  In the positioning apparatus according to the present invention, the Doppler frequency estimation means estimates the Doppler frequency from the moving speed using a direction cosine matrix. Furthermore, in the positioning apparatus according to the present invention, the Doppler frequency estimation means estimates the Doppler frequency based on the moving speed obtained from a sensor or the like that measures the motion state of the moving body.

  Furthermore, a positioning device according to the present invention detects a receiver that receives signals from a plurality of satellites, a code pseudorange used for positioning, a carrier Doppler frequency, and the like from signals received by the receiver, A positioning means for determining a position of a receiver mounted on the carrier, a pseudo-range calculating means for calculating a pseudo-range from the satellite to the receiver, a carrier integrating means for integrating the carrier Doppler frequency, and a carrier Pseudo distance smoothing means for smoothing pseudo distance using carrier integrated value from integrating means, moving speed calculating means for calculating moving speed of receiver from carrier Doppler frequency, received when satellite tracking is interrupted Doppler that reverses the positioning operation using the moving speed of the aircraft and estimates the Doppler frequency of the satellite carrier from the moving speed. A frequency estimation means, the carrier accumulation means, characterized by integrating the Doppler frequency tracking of the satellite is estimated in the case of interruption.

  Utilizing the present invention has the following effects. The first effect is that positioning by other satellites can be performed even if tracking is interrupted, and when the satellite is used for positioning after recovery from tracking interruption, the satellite is smoothed for a long time before tracking interruption and has high multipath suppression effect. The accuracy of positioning can be improved as compared with the prior art by converting the corrected pseudo-range that has been continuously converted into a Doppler frequency and using it for positioning.

  The second effect is that if the moving speed of the receiving device is known by using information from the outside such as a drive sensor, the Doppler frequency is estimated even if the satellite has not been positioned during tracking. Therefore, the same improvement effect can be obtained after recovery from tracking interruption.

  Hereinafter, embodiments of the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings.

  FIG. 1 is a configuration diagram showing an overall configuration of a GPS positioning device 10 according to an embodiment of the present invention. The GPS positioning device 10 includes a GPS antenna 17, a signal receiving unit 18, a plurality of ranging units (14 a, 14 b, 14 c), and a positioning calculation unit 21 including a moving speed notification device 22. A plurality of GPS satellites (12a, 12b, 12c) are arranged in the sky, and sometimes the shadow of the building 19 is lost.

  FIG. 7 is a configuration diagram showing a configuration of the GPS positioning device 100 in a configuration that is a reference of the present invention (hereinafter referred to as a reference configuration). The GPS positioning device 100 includes a plurality of ranging units 14 and a positioning calculation unit 21. Further, the distance measuring unit 14 has a main part for calculating the distance between the GPS satellite and the GPS positioning device 100 and a sub part for providing auxiliary data to the main part.

  The main part includes a GPS satellite identification unit 42, a tracking interruption detection unit 46, a navigation data demodulation unit 48, an orbit memory 52, a satellite position calculation unit 54, a code pseudorange calculation unit 56, and an offset estimation unit 58. And a corrected pseudo distance calculation unit 70.

  The subpart includes a satellite transmission time calculation unit 50, a carrier integration unit 62, a carrier integration reset unit 68, a carrier integration memory 64, and a ranging control unit 44 that controls the ranging unit 14.

  FIG. 6 is a flowchart showing a flow of positioning processing in the reference configuration. Hereinafter, the flow of the positioning process will be described with reference to FIGS. When the process is started, the GPS satellite tracking of step S42 is started through the repetition loop of step S40. The GPS signal transmitted from the GPS satellite is spread by a PN code, and in order to extract information, it is necessary to perform the spectrum despreading by the same PN code as the PN spread code used on the GPS satellite side. is there. A plurality of GPS satellites are assigned different PN codes, and spectrum despreading is performed using the PN codes of GPS satellites whose orbits are known in advance, and signals are sent to the distance measurement control unit 44 as signals representing correlation values with the PN codes. Entered.

  When the correlation value input to the distance measurement control unit 44 exceeds a predetermined value, the received signal is recognized as having been assigned the stored PN code. Further, the distance measurement control unit 44 controls the GPS satellite identification unit 42 so as to acquire data transmitted from the GPS satellite.

  In step S44, it is determined whether tracking is possible. The signal from the GPS satellite identified in step S42 is determined that the signal is not received by the tracking interruption detection unit 46 when the signal intensity is a predetermined value or less, and a signal is sent to the carrier integration reset unit 68, The carrier integration reset unit 68 resets the carrier integration memory 64 (step S48), and proceeds to step S52.

  If it is determined in step S44 that tracking is in progress, the process proceeds to step S46. The signal from the GPS satellite identified in step S42 is input to the navigation data demodulator 48 and the carrier integrator 62.

  The navigation data demodulator 48 extracts navigation data including GPS satellite orbit information, stores the data in the orbit memory 52, and inputs the data to the satellite transmission time calculator 50 (part of step S46). The carrier integration unit 62 stores the signal information from the GPS satellite in the carrier integration memory 64, and acquires the integration value (step S50).

  The satellite transmission time calculation unit 50 extracts data representing the time at which the GPS satellite transmitted a signal from the received signal, and inputs the data to the satellite position calculation unit 54 and the code pseudo distance calculation unit 56. The satellite position calculation unit 54 calculates the position on the satellite orbit related to the GPS satellite that transmitted the signal based on the orbit information of the satellite including the navigation data read from the orbit memory 52 and the time when the GPS satellite transmitted the signal. The position data is input to the positioning calculation unit 21. The code pseudo-range calculation unit 56 subtracts the time when the GPS satellite transmits the signal from the time of the clock provided in the GPS positioning device 100, so that the time required for the signal to reach the GPS positioning device 100 from the GPS satellite, That is, the propagation time is calculated (part of step S46).

  Then, the distance from the GPS positioning device 100 to the GPS satellite is calculated by multiplying the propagation time by the propagation speed of the electromagnetic wave to obtain the GPS satellite distance. The code pseudo distance calculation unit 56 inputs data in which the GPS satellite and the GPS satellite distance are associated with each other to the offset estimation unit 58 (end of step S46).

  Since the GPS satellite is an orbiting satellite that makes one orbit in 12 hours, a Doppler frequency shift of about ± 5 kHz occurs in the signal from the satellite. The correction pseudorange calculation unit 70 measures the Doppler frequency shift amount observed in the carrier of the received signal, and calculates the time change rate of the GPS satellite distance based on the measured amount.

  The time change rate of the GPS satellite distance is an apparent approach speed of the GPS satellite observed from the GPS positioning device 100. Therefore, if the integration calculation is performed with the time change rate of the GPS satellite distance as the lower limit of the integration range and the current time as the upper limit of the integration range, the time from the time when the integration range is adjusted to the current time is calculated. The amount of change in the GPS satellite distance at is calculated (step S50).

  This amount of change is caused by the movement of the GPS satellite and the movement of the GPS positioning device 100. Hereinafter, the time when the lower limit of the integration range is set is the initial time, and the change amount of the GPS satellite distance is the distance change amount. Note that the amount of change in distance from the initial time to the current time plus the GPS satellite distance at the initial time matches the GPS satellite distance at the current time if there is no error in the value. The carrier integrating unit 62 calculates the distance change amount by the integral calculation as described above, and inputs the data to the offset estimating unit 58.

  The offset estimation unit 58 calculates an offset distance obtained by subtracting a distance change amount by the data input by the carrier integration unit 62 from the GPS satellite distance by the data input by the code pseudo distance calculation unit 56 (step S52). However, the GPS satellite distance and the distance change amount related to the calculation of the offset distance must be at the same time on the basis of the time indicated by the clock included in the GPS positioning device 100.

  Since the GPS satellite distance includes a noise-free fluctuation having a high frequency component, the offset distance calculated based on the fluctuation also includes the fluctuation. Therefore, after subtracting the distance change amount from the GPS satellite distance, the offset estimation unit 58 calculates the offset distance after removing the fluctuation with a low-pass filter (step S54).

  The offset estimation unit 58 inputs the offset distance data calculated in this way to the corrected pseudo distance calculation unit 70 together with the GPS satellite position data, the GPS satellite distance data, and the distance change data. . The corrected pseudo distance calculation unit 70 newly calculates the GPS satellite distance by adding the offset distance to the distance change amount. This newly calculated GPS satellite distance is referred to as a corrected pseudo distance to distinguish it from the previous GPS satellite distance, and this data is output to the positioning calculation unit 21. The positioning calculation unit 21 obtains pseudo correction distances from the plurality of ranging units 14 and calculates the position of the three-dimensional space (step S56), and returns to the first loop (step S40).

  FIG. 5 is an explanatory diagram showing a change in pseudorange from the satellite to the receiver according to the reference configuration. 5A is a result obtained by the processing of the offset estimation unit 58 in FIG. 7, and similarly, FIG. 5B is a result obtained by the processing of the corrected pseudo distance calculation unit 70.

As described above, the code pseudo distance R (t) is calculated by the code pseudo distance calculation (step S46) shown in FIG. Next, the carrier Doppler frequency integration value D (t) is calculated by carrier integration (step S50). Next, a temporary offset E (t) = R (t) −D (t) is obtained by offset estimation (step S52), and E (t) is smoothed by a low-pass filter (hereinafter referred to as LPF). Thus, the estimated offset value R _E (t) = LPF (E (t)) is obtained.

Then, the corrected pseudo distance R _C (t) = R _E (t) + D (t) is obtained by the corrected pseudo distance calculation (step S54). Further, a correction pseudorange R _E (t) is obtained by positioning calculation (step S56), and a three-dimensional position is determined from a plurality of pseudoranges. However, when the satellite used for positioning enters the shadow of a building or the like and the tracking of the satellite is interrupted, the Doppler frequency integrated value D (t) of the satellite must be reset to 0 in the carrier integrated reset process. (Step S48).

For this reason, even if tracking is performed again, it takes time until a sufficiently smoothed offset estimated value R _E (t) is obtained. During this time, correction that cannot sufficiently suppress the influence of multipath errors The pseudo-range R _E (t) is obtained, and an error due to multipath may occur in the positioning calculation result using the satellite for positioning. Therefore, in the present embodiment, an inverse matrix H ⁻¹ of the direction cosine matrix H is used for positioning calculation as a configuration shown below.

FIG. 2 is a configuration diagram showing the configuration of the GPS positioning device 10 according to the first embodiment of the present invention. The difference from the reference configuration of FIG. 7 is that a carrier estimation unit 60 and a moving speed notification device 22 are added. The tracking satellite calculates the corrected pseudorange R _e (t) as in the reference configuration, and performs positioning calculation. Usually, the positioning calculation unit 21 calculates the position of the GPS positioning device 10 from the pseudo distance, and also calculates the moving speed V (t) of the GPS positioning device 10 from the carrier Doppler frequency. The positioning calculation is performed using an inverse matrix H ⁻¹ of the direction cosine matrix H indicating the relative positional relationship between the satellite and the GPS positioning device 10 (general user) using a Taylor series linear model. The matrix H is well known in the art.

  FIG. 3 is a flowchart showing a flow of positioning processing in the embodiment of the present invention. Hereinafter, a description will be given with reference to FIGS. 2 and 3. When the process is started, the GPS satellite tracking of step S12 is started through the repetition loop of step S10. The GPS signal transmitted from the GPS satellite is subjected to spectrum despreading using the PN code of the GPS satellite whose orbit is known in advance, and is input to the distance measurement control unit 44 as a signal representing a correlation value with the PN code.

  When the correlation value input to the distance measurement control unit 44 exceeds a predetermined value, the received signal is recognized as having been assigned the stored PN code. Further, the distance measurement control unit 44 controls the GPS satellite identification unit 42 so as to acquire data transmitted from the GPS satellite.

  In step S14, the distance measurement unit 14 that is determined to have the tracking interruption by the tracking interruption detection unit 46 obtains the moving speed V (t) of the receiver from the positioning calculation unit 21 (step S18), and provides it to the carrier estimation unit 60. The carrier estimation unit 60 estimates the Doppler frequency f (t) of the GPS satellite carrier from the moving velocity V (t) using the direction cosine matrix H obtained from the positioning calculation unit 21 (step S20). The carrier integration unit 62 acquires the estimated topler frequency f (t), stores it in the carrier integration memory 64, and integrates the estimated Doppler frequency as the Doppler frequency integration value D (t) (step S22). .

  If it is determined in step S14 that tracking is in progress, the process proceeds to step S16. The signal from the GPS satellite identified in step S42 is input to the navigation data demodulator 48, the satellite transmission time calculator 50, and the carrier integrator 62.

  The navigation data demodulator 48 extracts navigation data including GPS satellite orbit information, stores the data in the orbit memory 52, and the orbit memory 52 inputs the data to the satellite position calculator 54 (one in step S16). Part). The carrier integrating unit 62 stores the signal from the GPS satellite in the carrier integrating memory 64 and acquires the integrated value (step S22).

  The satellite transmission time calculation unit 50 extracts data representing the time at which the GPS satellite transmitted a signal from the received signal, and inputs the data to the satellite position calculation unit 54 and the code pseudo distance calculation unit 56. The satellite position calculation unit 54 calculates the position of the GPS satellite that transmitted the signal on the satellite orbit based on the orbit information of the satellite including the navigation data and the time when the GPS satellite transmitted the signal, and the position data is code-simulated. Input to the distance calculator 56. The code pseudo-range calculation unit 56 subtracts the time at which the GPS satellite transmits the signal from the time from the clock provided in the GPS positioning device 100, so that the time required for the signal to reach the GPS positioning device 100 from the GPS satellite. That is, the propagation time is calculated (part of step S24).

  Then, the distance from the GPS positioning device 100 to the GPS satellite is calculated by multiplying the propagation time by the propagation speed of the electromagnetic wave to obtain the GPS satellite distance. The code pseudo distance calculation unit 56 inputs data in which the GPS satellite and the GPS satellite distance are associated with each other to the offset estimation unit 58.

  Since the GPS satellite is an orbiting satellite, a Doppler frequency shift of about ± 5 kHz occurs in the signal from the satellite. The correction pseudorange calculation unit 70 measures the Doppler frequency shift amount observed in the carrier of the received signal, and calculates the time change rate of the GPS satellite distance based on the measured amount.

  The time change rate of the GPS satellite distance is an apparent approach speed of the GPS satellite observed from the GPS positioning device 100. Therefore, if the integration calculation is performed with the time change rate of the GPS satellite distance as the lower limit of the integration range and the current time as the upper limit of the integration range, the time from the time when the integration range is adjusted to the current time is calculated. The amount of change in the GPS satellite distance at is calculated.

  This amount of change is caused by the movement of the GPS satellite and the movement of the GPS positioning device 100. Hereinafter, the time when the lower limit of the integration range is set is the initial time, and the change amount of the GPS satellite distance is the distance change amount. Note that the amount of change in distance from the initial time to the current time plus the GPS satellite distance at the initial time matches the GPS satellite distance at the current time if there is no error in the value. The carrier integrating unit 62 calculates the distance change amount by the integral calculation as described above, and inputs the data to the offset estimating unit 58 (end of step S24).

  The offset estimation unit 58 calculates an offset distance obtained by subtracting the distance change amount by the data input by the carrier integration unit 62 from the GPS satellite distance by the data input by the code pseudo distance calculation unit 56 (step S26). However, the GPS satellite distance and the distance change amount related to the calculation of the offset distance must be at the same time on the basis of the time indicated by the clock included in the GPS positioning device 100.

  Since the GPS satellite distance includes a noise-free fluctuation having a high frequency component, the offset distance calculated based on the fluctuation also includes the fluctuation. Therefore, the offset estimation unit 58 calculates the offset distance after subtracting the distance change amount from the GPS satellite distance and then removing the fluctuation by the low-pass filter.

  The offset estimation unit 58 inputs the offset distance data calculated in this way to the corrected pseudo distance calculation unit 70 together with the GPS satellite position data, the GPS satellite distance data, and the distance change data. . The corrected pseudo distance calculation unit 70 newly calculates the GPS satellite distance by adding the offset distance to the distance change amount. This newly calculated GPS satellite distance is called a corrected pseudo distance to distinguish it from the previous GPS satellite distance, and this data is output to the positioning calculation unit 21 (step S28). The positioning calculation unit 21 obtains pseudo correction distances from the plurality of ranging units 14, calculates the position of the three-dimensional space, further executes the movement speed calculation (step S30), and the first loop (step S10). Return to.

Thus, during positioning, even if tracking of the satellite is interrupted, it is not necessary to reset the Doppler integrated value D (t), and the integration can be continued. For this reason, even if the satellite whose tracking is interrupted is used for positioning, it is possible to obtain the corrected pseudorange R _e (t) while maintaining the enhanced smoothing result.

FIG. 4 is a configuration diagram showing the configuration of the GPS control device according to the second embodiment of the present invention. The difference from the first embodiment is obtained from the outside such as a drive sensor (DR sensor) instead of the method of estimating the Doppler frequency f (t) from the moving speed V (t) obtained from the positioning calculation unit 21. Conversely, the Doppler frequency f (t) is estimated from the moving speed V (t). The processing flow obtains the Doppler frequency f _s (t) for the satellite movement from the satellite position calculation unit 54.

Next, it obtains its own moving speed from an external DR sensor. And the Doppler frequency f _r (t) for its own movement is calculated from the moving speed V (t) by performing the reverse operation of the normal positioning calculation. Further, by calculating the frequency offset ft (t) of the internal clock of the watch from the time the error obtained from the positioning calculation unit _21, by _{f (t) = f s (} t) + f r (t) -f t (t) Estimate the Doppler frequency f (t) of the satellite.

  As described above, by using this embodiment, positioning by other satellites can be performed even when tracking is interrupted, and when the satellite is used for positioning after recovery from tracking interrupts, the satellite has not been used for a long time since the tracking was interrupted. The correction pseudorange that has been smoothed and continues to have a high effect of multipath suppression is used for positioning, and the positioning accuracy can be improved as compared with the prior art.

  In addition, if the moving speed of the receiving device is known from outside information such as a drive sensor, the Doppler frequency can be estimated even if the satellite has not been positioned during tracking, The same improvement effect can be obtained after recovery from tracking interruption.

  In the present embodiment, the position data after the positioning calculation is not corrected, but it is also preferable to perform a process such as smoothing.

It is a lineblock diagram showing the whole positioning device composition in an embodiment of the present invention. It is a block diagram which shows the structure of the GPS control apparatus in the 1st Embodiment of this invention. It is a flowchart figure which shows the flow of the positioning process in embodiment of this invention. It is a block diagram which shows the structure of the GPS control apparatus in the 2nd Embodiment of this invention. It is explanatory drawing which shows the change of the pseudo distance between the satellite and receiver by a reference structure. It is a flowchart figure which shows the flow of the positioning process in a reference structure. It is a block diagram which shows the structure of the GPS positioning apparatus in a reference structure.

Explanation of symbols

  10 GPS positioning devices, 12 GPS satellites, 14 ranging units, 17 antennas, 18 signal receiving units, 19 buildings, 21 positioning calculation units, 22 moving speed notification units, 42 satellite identification units, 44 ranging control units, 46 tracking interruption Detection unit, 48 Navigation data demodulation unit, 50 Satellite transmission time calculation unit, 52 Orbit memory, 54 Satellite position calculation unit, 56 Code pseudorange calculation unit, 58 Offset estimation unit, 60 Carrier estimation unit, 68 Carrier integration reset unit, 62 Carrier integration unit, 64 carrier integration memory, 70 correction pseudorange calculation unit, 100 GPS positioning device.

Claims (7)

A receiver that receives signals from multiple satellites, and a positioning that obtains the position of the receiver mounted on the moving object by detecting the code pseudorange and carrier Doppler frequency used for positioning from the signals received by the receiver A positioning device comprising:
A pseudo distance calculating means for calculating a pseudo distance from the satellite to the receiver;
Carrier integration means for integrating the carrier Doppler frequency;
A moving speed calculating means for calculating the moving speed of the receiver from the carrier Doppler frequency;
Doppler frequency estimation means for estimating the Doppler frequency of the carrier of the satellite from the moving speed by performing the reverse calculation of the positioning calculation using the moving speed of the receiver when the satellite tracking is interrupted,
Have
The positioning device characterized in that the carrier integration means integrates the Doppler frequency estimated when the tracking of the satellite is interrupted. The positioning device according to claim 1,
The Doppler frequency estimation means is
A positioning apparatus that estimates a Doppler frequency from a moving speed using a direction cosine matrix. The positioning device according to claim 1 or 2,
The Doppler frequency estimation means is
A positioning apparatus that estimates a Doppler frequency based on a moving speed obtained from a sensor or the like that measures a motion state of a moving body. A receiver that receives signals from multiple satellites, and a positioning that obtains the position of the receiver mounted on the moving object by detecting the code pseudorange and carrier Doppler frequency used for positioning from the signals received by the receiver A positioning device comprising:
A pseudo distance calculating means for calculating a pseudo distance from the satellite to the receiver;
Carrier integration means for integrating the carrier Doppler frequency;
Pseudo distance smoothing means for smoothing the pseudo distance using the carrier integrated value from the carrier integrating means;
A moving speed calculating means for calculating the moving speed of the receiver from the carrier Doppler frequency;
Doppler frequency estimation means for estimating the Doppler frequency of the carrier of the satellite from the moving speed by performing the reverse calculation of the positioning calculation using the moving speed of the receiver when the satellite tracking is interrupted,
Have
The positioning device characterized in that the carrier integration means integrates the Doppler frequency estimated when the tracking of the satellite is interrupted. A positioning process including a receiving process for receiving signals from a plurality of satellites and a positioning process for detecting a Doppler frequency of a code or a carrier used for positioning from the received signals to obtain a position of a receiver mounted on a moving body. In the method
A pseudo-range calculating step for calculating a corrected pseudo-range from the satellite;
A carrier integration process for integrating the carrier Doppler frequency;
A moving speed calculating step of calculating the moving speed of the receiver from the carrier Doppler frequency;
Doppler frequency estimation step of performing reverse calculation of positioning calculation using the moving speed of the receiver when satellite tracking is interrupted, and estimating the Doppler frequency of the carrier of the satellite from the moving speed;
Including
The carrier integration calculation step integrates the Doppler frequency estimated when the tracking of the satellite is interrupted. The positioning method according to claim 5, wherein
The Doppler frequency estimation method is
A positioning method characterized by estimating a Doppler frequency from a moving speed using a direction cosine matrix. In the positioning method according to claim 5 or 6,
The Doppler frequency estimation method is
A positioning method characterized by estimating a Doppler frequency based on a moving speed obtained from a sensor or the like for measuring a moving state of a moving body.

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