JP2010112759A - Mobile body positioning apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To measure the position of a mobile body more reliably and accurately. <P>SOLUTION: The mobile body positioning apparatus includes: a reception means for receiving signals from a plurality of satellites; an observed pseudo range calculating means for calculating an observed pseudo range based on the signals received by the reception means; and a positioning computation means for performing repeated positioning computation based on the observed pseudo range calculated by the observed pseudo range calculating means. The mobile object positioning apparatus further includes an estimated pseudo range calculating means for calculating an estimated pseudo range by adding a variation of ADR (Accumulated Doppler Range) to a distance determined from a last positioning result and the position of the satellite while the positioning computation means is performing repeated positioning computation. Under a predetermined condition, the positioning computation means performs positioning computation by using an estimated pseudo range calculated by the estimated pseudo range calculating means as a substitute for an observed pseudo range calculated by the observed pseudo range calculating means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a moving body position measuring apparatus that measures the position of a moving body based on a signal from a satellite.

  2. Description of the Related Art Conventionally, a device that measures the position of a moving body based on a signal from a satellite has been widely used. One problem with such devices is what is called multipath. This is because the distance (pseudo distance) between the satellite and the receiver is shifted from the actual distance by receiving a signal reflected by a building or the like, and as a result, the current position of the apparatus is erroneously recognized.

In view of such a point, an invention relating to an apparatus using a Doppler frequency that is less affected by multipath has been disclosed (for example, see Patent Document 1). In this device, the signal from the satellite is received by the GPS antenna, the Doppler frequency and the pseudorange are calculated from the received signal, and the pseudorange is estimated by using the Doppler frequency and the previously calculated pseudorange. The positioning calculation is performed by selectively using the pseudo distance and the pseudo distance calculated from the received signal.
JP 2001-4734 A

  However, in the conventional GPS receiver, the pseudorange is estimated by taking the Doppler frequency into consideration with the pseudorange previously calculated using the signal from the satellite as a reference when estimating the pseudorange. . Therefore, when the signal from the satellite is interrupted for a relatively long time or when a multipath occurs, the pseudorange may not be estimated or may be less accurate.

  The present invention is for solving such problems, and a main object of the present invention is to provide a moving body position measuring device capable of positioning the position of the moving body more reliably and with high accuracy.

In order to achieve the above object, the first aspect of the present invention provides:
Receiving means for receiving signals from a plurality of satellites;
Observation pseudorange calculation means for calculating an observation pseudorange based on the signal received by the reception means;
Positioning calculation means for repeatedly performing positioning calculation based on the observation pseudo distance calculated by the observation pseudo distance calculation means;
A mobile body positioning device comprising:
An estimated pseudo-distance that calculates an estimated pseudo-range by adding an amount of change in ADR (Accumulated Doppler Range) to the distance obtained from the positioning result obtained previously and the satellite position while the positioning calculation means repeatedly performs positioning calculations. A calculation means,
The positioning calculation means performs a positioning calculation using the estimated pseudo distance calculated by the estimated pseudo distance calculation means instead of the observation pseudo distance calculated by the observation pseudo distance calculation means in a predetermined case. To do.

  According to the first aspect of the present invention, since the estimated pseudo distance calculating means for calculating the estimated pseudo distance using the ADR change amount that is relatively unaffected by the deterioration of the reception accuracy due to multipath or the like, the observation pseudo distance is provided. It is possible to determine the position of the moving body with higher accuracy as compared with the case where the positioning calculation is performed using only the position. Further, when the “predetermined case” continues for a certain period of time, the positioning result serving as a reference for the estimated pseudo-distance is a positioning result estimated using ADR. For this reason, the position of the moving body can be more reliably determined as compared with the case where the estimated pseudo distance is obtained by simply adding the amount of change in ADR to the observed pseudo distance.

  Therefore, the position of the moving body can be determined more reliably and with high accuracy.

The second aspect of the present invention is:
Receiving means for receiving signals from a plurality of satellites;
Observation pseudorange calculation means for calculating an observation pseudorange based on the signal received by the reception means;
Positioning calculation means for repeatedly performing positioning calculation based on the observation pseudo distance calculated by the observation pseudo distance calculation means;
A mobile body positioning device comprising:
An estimated pseudo-distance that calculates an estimated pseudo-range by adding an amount of change in ADR (Accumulated Doppler Range) to the distance obtained from the positioning result obtained previously and the satellite position while the positioning calculation means repeatedly performs positioning calculations. A calculation means,
The positioning calculation means determines whether or not the reception accuracy of a satellite capable of receiving a signal is low, and the satellite determined to have low reception accuracy is replaced with the observation pseudorange calculated by the observation pseudorange calculation means. Thus, the positioning calculation is performed using the estimated pseudo distance calculated by the estimated pseudo distance calculating means.

  According to the second aspect of the present invention, since the estimated pseudo distance calculation means for calculating the estimated pseudo distance using the ADR change amount that is relatively unaffected by the deterioration of the reception accuracy due to multipath or the like is provided, the observation pseudo distance It is possible to determine the position of the moving body with higher accuracy as compared with the case where the positioning calculation is performed using only the position. Further, when the “predetermined case” continues for a certain period of time, the positioning result serving as a reference for the estimated pseudo-distance is a positioning result estimated using ADR. For this reason, the position of the moving body can be more reliably determined as compared with the case where the estimated pseudo distance is obtained by simply adding the amount of change in ADR to the observed pseudo distance.

  Therefore, the position of the moving body can be determined more reliably and with high accuracy.

In the first or second aspect of the present invention,
Sub-positioning calculation means for performing positioning calculation based on the vehicle speed vector;
Positioning result selection means for performing accuracy determination between the positioning result measured by the positioning calculation means and the positioning result measured by the sub-positioning calculation means, and selecting any positioning result based on the accuracy determination result When,
May be provided.

In the first or second aspect of the present invention,
A moving amount calculating means for calculating the moving amount of the moving body based on the behavior of the moving body;
The estimated pseudo distance calculation means regards the positioning result using the movement amount calculated by the movement amount calculation means as the positioning result measured last time when there is no positioning result measured last time. It may be a means for calculating the estimated pseudorange.

  In this case, for example, even after the signal from the satellite is completely blocked after passing through the tunnel, the positioning calculation of the moving body position can be resumed promptly.

  ADVANTAGE OF THE INVENTION According to this invention, the moving body position positioning apparatus which can position the position of a moving body more reliably and with high precision can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the accompanying drawings.

<First embodiment>
FIG. 1 is a system configuration diagram showing an overall configuration of a GNSS (Global Navigation System) to which a mobile body positioning apparatus according to the present invention is applied. GNSS is a positioning system in which a positioning device mounted on a moving body uses a signal from a satellite to measure the position of the moving body. A positioning system using satellites such as GPS (Global Positioning System), Galileo, Glonass, etc. Including. In the following description, GPS will be described as a basic configuration, but the present invention is not limited to GPS and can be widely applied to any GNSS.

  As shown in FIG. 1, the GPS has a GPS satellite 10 that orbits the earth and a vehicle 90 that is located on the earth and can move on the earth. The vehicle 90 is merely an example of a moving body, and other moving bodies include motorcycles, railways, ships, airplanes, hawk lifts, robots, information terminals such as mobile phones that move as people move, and the like. There can be.

  The GPS satellite 10 constantly broadcasts navigation messages (satellite signals) toward the earth. The navigation message includes satellite orbit information (ephemeris and almanac) regarding the corresponding GPS satellite 10, a clock correction value, and an ionosphere correction coefficient. The navigation message is spread by the C / A code, is carried on the L1 wave (frequency: 1575.42 MHz), and is constantly broadcast toward the earth. The L1 wave is a combined wave of a Sin wave modulated with a C / A code and a Cos wave modulated with a P code (Precision Code), and is orthogonally modulated. The C / A code and the P code are pseudo noise codes, and are code strings in which -1 and 1 are irregularly arranged periodically.

  Currently, 24 GPS satellites 10 orbit the earth at an altitude of about 20,000 km, and each of the four GPS satellites 10 is evenly arranged on six Earth orbit planes inclined by 55 degrees. ing. Therefore, as long as the sky is open, at least five GPS satellites 10 can be observed at any time on the earth.

  The vehicle 90 is mounted with the mobile body position positioning device 1 as a mobile body position positioning device. The mobile body positioning device 1 measures the position of the vehicle 90 based on the satellite signal from the GPS satellite 10, as will be described in detail below.

FIG. 2 is a system configuration example of the mobile body positioning device 1 mounted on the vehicle 90 of FIG. In FIG. 2, only _one GPS satellite 10 ₁ (subscript is a satellite number) is shown in order to avoid complicated explanation. Accordingly, it will be representatively described signal processing relating satellite signal from the GPS satellite 10 _1. Signal processing relating satellite signal from the GPS satellite 10 ₁ is a signal processing is substantially the same as about the satellite signals from the other GPS satellites ₁₀ 2, 10 _3, etc..

  As shown in FIG. 2, the mobile body positioning device 1 of the present embodiment has a GPS antenna 20 and an information processing device 30 as main components. A vehicle sensor 80 is connected to the information processing apparatus 30.

  The information processing apparatus 30 is, for example, a microcomputer, and functions as a functional block that functions by executing a program stored in a ROM, as an observation pseudorange calculation unit 40, an estimated pseudorange calculation unit 50, and a positioning calculation unit 60. .

  The vehicle sensor 80 may be built in the moving body position positioning device 1 or may be provided outside the moving body position positioning device 1 and connected by a bus or the like. The vehicle sensor 80 is a sensor that acquires information (hereinafter referred to as “vehicle information”) related to the movement amount and direction (azimuth) of the vehicle 90, and may be a combination of a plurality of types of sensors. For example, the vehicle sensor 80 may be a combination of a magnetic impedance sensor (geomagnetic sensor) that detects the orientation of the vehicle 90 and an acceleration sensor that detects the acceleration of the vehicle 90. Alternatively, the vehicle sensor 80 may be a combination (that is, an INS sensor) of an acceleration sensor and a yaw rate sensor (gyro sensor) that detects the velocity (angular velocity) of the vehicle 90 in the yaw direction. Vehicle information from the vehicle sensor 80 is input to the positioning calculation unit 60 at predetermined intervals.

Observation pseudorange calculation portion 40 for a signal GPS antenna 20 receives, performs C / A code synchronization using the replica C / A code is generated internally, it takes out a navigation message, GPS satellite 10 ₁ and the vehicle An observation pseudo-range ρ with 90 (more precisely, the mobile body positioning device 1) is calculated. Observation pseudorange ρ and, unlike the true distance between the GPS satellite 10 ₁ and the vehicle 90, including the error due to clock error (clock bias) and radio wave propagation velocity changes. There are a wide variety of C / A code synchronization methods, and any appropriate method may be employed. For example, a code phase in which the correlation value of the replica C / A code with respect to the received C / A code peaks can be tracked using DDL (Delay-Locked Loop).

Here, the observation pseudorange ρ with respect to the GPS satellite 10 ₁ is calculated, for example, by the following equation (1).

  ρ = N × 300 (1)

Here, N corresponds to the number of bits of the C / A code between the GPS satellite 10 ₁ and the vehicle 90, based on the phase and the mobile positioning device 1 inside the receiver clock of the C / A code replica Calculated. The numerical value 300 is derived from the fact that the C / A code has a 1-bit length of 1 μs and a length corresponding to 1 bit of about 300 m (1 μs × light speed). A signal representing the observation pseudo distance ρ calculated in this way is input to the positioning calculation unit 60. Note that the calculated observation pseudorange ρ may be input to the positioning calculation unit 60 after being subjected to carrier smoothing by a filter (not shown) using, for example, a Doppler frequency change amount Δf described later.

  The estimated pseudo-range calculation unit 50 has a function of measuring the carrier wave phase of the satellite signal, and measures the Doppler frequency change amount Δf of the Doppler-shifted received carrier wave using an internally generated replica carrier. The Doppler frequency change amount Δf is measured as a difference (= fr−fc) between the replica carrier frequency fr and the known carrier frequency fc (1575.42 MHz). Such a function may be realized by a phase-locked loop (PLL) that calculates a carrier correlation value using a replica carrier and tracks a received carrier.

  Further, the estimated pseudo distance calculation unit 50 calculates an ADR (Accumulated Doppler Range) by integrating the Doppler frequency change amount Δf.

Then, the estimated pseudo distance calculation unit 50 changes the ADR to a distance ρ ₋₁ obtained by the following equation (2) from the positioning result and the satellite position previously determined while the positioning calculation unit 60 repeatedly performs the positioning calculation. The amount is added, and the estimated pseudo distance ρ # is calculated by the following equation (3). A signal representing the estimated pseudo distance ρ # is input to the positioning calculation unit 60. Note that “previous” means a value calculated last time during execution of repetitive processing. It is assumed that the previously calculated value is sequentially stored in the RAM or the like of the information processing apparatus 30.

ρ＃＝ρ_−１＋（ＡＤＲの今回算出値−ＡＤＲの前回算出値） …（３）

ρ # = ρ ₋₁ + (currently calculated value of ADR−previous calculated value of ADR) (3)

Positioning operation unit 60, the position of the GPS satellite 10 ₁ (hereinafter, referred to as "satellite position") is calculated. Specifically, the positioning calculation unit 60, based on the satellite orbit information and the current time of the navigation message, the GPS satellite 10 ₁ calculates the current position (X1, Y1, Z1) in the world coordinate system. Since the GPS satellite 101 is _one of artificial satellites, its movement is limited to a certain plane (orbital plane) including the center of gravity of the earth. Further, the trajectory of the GPS satellites 10 ₁ are elliptic motion to one focus global centroid, by sequentially numerical equations of Kepler, can be calculated GPS satellite 10 ₁ in position on the track surface. The position of the GPS satellite 10 ₁ (X1, Y1, Z1), in consideration of the fact that the equatorial plane of the GPS satellites 10 ₁ of the raceway surface and the world coordinate system is in rotational relationship, GPS satellites 10 in orbit plane It is obtained by converting the position of ₁ to a three-dimensional rotational coordinate. As shown in FIG. 3, the world coordinate system is defined by an X axis and a Y axis that are orthogonal to each other in the equator plane, and a Z axis that is orthogonal to both axes with the center of gravity of the earth as the origin.

  Further, the positioning calculation unit 60 basically determines the position (Xu, Yu, Zu) of the vehicle 90 based on the calculation result of the satellite position and the observation pseudo distance ρ supplied from the observation pseudo distance calculation unit 40. Measure. The position of the vehicle 90 is derived on the principle of triangulation using the observed pseudoranges ρ and the satellite positions obtained for the three GPS satellites 10. In this case, since the observation pseudorange ρ includes a clock error as described above, the clock error component is removed using the observation pseudorange ρ and the satellite position obtained for the fourth GPS satellite 10. Hereinafter, this positioning method is referred to as normal positioning. The positioning cycle for normal positioning may be, for example, an observation cycle (for example, 1 ms) or a predetermined number of observation cycles (for example, 50 ms or 100 ms). The positioning results (satellite position and vehicle position) are output to the estimated pseudo-range calculator 50 and also provided to an in-vehicle navigation system or the like.

  The positioning method of the position of the vehicle 90 is not limited to the single positioning as described above, but may be interference positioning (a method in which received data at a fixed station installed at a known point is used in combination). In the case of interference positioning, the position of the vehicle 90 is measured using the single phase difference or double phase difference of the observation pseudo distance ρ obtained by the fixed station and the vehicle 90 as described above.

  In addition, the positioning calculation unit 60 performs a positioning calculation using the estimated pseudo distance ρ # calculated by the estimated pseudo distance calculation unit 50 in place of the observation pseudo distance ρ calculated by the observation pseudo distance calculation unit 40 in a predetermined case. To do. As a result, the positioning result supplied to the estimated pseudo distance calculation unit 50 is calculated using the estimated pseudo distance ρ #.

  Here, the predetermined case is, for example, when the reception accuracy of any of the receivable satellites is deteriorated and the number of satellites for which the estimated pseudorange ρ # can be calculated is equal to or greater than the predetermined number. It is. Here, the case where the estimated pseudorange ρ # cannot be calculated is a scene where the satellite can be received for the first time this time as a specific scene when there is no previously calculated value of ADR. Further, the predetermined number is the number of satellites necessary for performing the positioning calculation, and is generally four. However, it can be increased or decreased by a positioning calculation method.

  Whether or not the reception accuracy is deteriorated, more specifically, whether a multipath has occurred or not is determined when the observation pseudorange ρ calculated by the observation pseudorange calculation unit 40 jumps by a predetermined value or more (or multipath has occurred). This can be determined by setting a flag indicating that the pass has been completed. Since such determination does not form the core of the present invention, detailed description thereof is omitted. The determination may be made by any method exemplified above.

  FIG. 4 is a flowchart showing a flow of characteristic processing executed by the estimated pseudo distance calculation unit 50 according to the first embodiment of the present invention. This flow is repeatedly executed with a predetermined period.

The estimated pseudorange calculation unit 50 executes the following processes of S100 and S102 for each satellite. First, a distance ρ ₋₁ is calculated from the previous positioning result and satellite coordinates according to the above equation (2) (S100).

Then, according to the above equation (3), the estimated pseudo distance ρ # is calculated by adding the amount of change in ADR to the calculated distance ρ− ₁ (S102).

  FIG. 5 is a flowchart showing a flow of characteristic processing executed by the positioning calculation unit 60 according to the first embodiment of the present invention. This flow is repeatedly executed in synchronization with a predetermined period in the flowchart of FIG.

  First, the positioning calculation unit 60 determines whether or not the reception accuracy of all satellites is good (S200).

  If the reception accuracy of all the satellites is good, the positioning calculation is executed using the observation pseudorange ρ (S202).

  On the other hand, when the reception accuracy of all the satellites is not good, it is determined whether or not the number of satellites for which the estimated pseudorange ρ # can be calculated is less than a predetermined number (S204).

  If the number of satellites for which the estimated pseudorange ρ # can be calculated is less than the predetermined number, the positioning calculation is executed using the observation pseudorange ρ (S202). At this time, the observation pseudorange ρ for a satellite whose reception accuracy is deteriorated may be excluded.

  On the other hand, if the number of satellites for which the estimated pseudorange ρ # can be calculated is equal to or greater than the predetermined number, the positioning calculation is executed using the estimated pseudorange ρ # (S206).

  As a result of such processing, when the reception accuracy is deteriorated due to multipath or the like for any satellite in an urban area or the like, the estimated pseudorange ρ # is used. As a result, the position of the vehicle 90 can be measured with higher accuracy than when the positioning calculation is performed using the observation pseudo distance ρ.

In addition, when a state in which reception accuracy deteriorates due to multipath or the like continues for a certain period of time for any of the satellites as described above, the distance ρ _{−1 serving as} a reference for the estimated pseudorange ρ # is estimated using ADR. It is based on the obtained positioning result. For this reason, the position of the vehicle 90 can be more reliably determined as compared with the case where the estimated pseudo distance ρ # is obtained simply by adding the amount of change in ADR to the observed pseudo distance ρ.

  According to the mobile body positioning device 1 of the present embodiment described above, the position of the mobile body can be measured more reliably and with high accuracy.

<Second embodiment>
Hereinafter, the mobile body positioning device 2 according to the second embodiment of the present invention will be described. The mobile body positioning device 2 is identical to the mobile body positioning device 1 of the first embodiment except for the processing contents of the positioning calculation unit 60 differing from the mobile body positioning device 1 of the first embodiment. Since it is common regarding the contents, FIG. 1 to FIG. 4 and the description thereof are used, and the description of the common components is omitted.

  The positioning calculation unit 60 according to the present embodiment determines whether or not a multipath has occurred for a satellite that can receive a signal, and the satellite that has determined that a multipath has occurred is calculated by the observation pseudorange calculation unit 40. The positioning calculation is performed using the estimated pseudo distance calculated by the estimated pseudo distance calculating unit 50 instead of the observed pseudo distance.

  FIG. 6 is a flowchart showing a flow of characteristic processing executed by the positioning calculation unit 60 according to the second embodiment of the present invention. This flow is repeatedly executed in synchronization with a predetermined period in the flowchart of FIG.

  The positioning calculation unit 60 executes the following processes of S300 to S304 for each satellite. First, it is determined whether the reception accuracy of the selected satellite is good (for example, no multipath has occurred) (S300).

  When the reception accuracy of the selected satellite is good, the observation pseudorange ρ is adopted for the satellite (S302).

  On the other hand, when the reception accuracy of the selected satellite is poor, the estimated pseudorange ρ # is adopted for the satellite (S304).

  When it is determined which pseudorange is to be adopted for each satellite, positioning calculation is performed using the pseudoranges adopted for each satellite (S306).

  At this time, the observed pseudo distance ρ and the estimated pseudo distance ρ # may be mixed. Therefore, the positioning calculation unit 60 of the present embodiment solves the following equations using the least square method and the Newton method, and calculates the clock error Δt when calculating the observed pseudorange ρ and the estimated pseudorange ρ #. The clock error Δt # is derived.

  By such processing, when the reception accuracy of some satellites deteriorates due to multipath or the like, positioning calculation is performed using both the observation pseudorange ρ and the estimated pseudorange ρ #. As a result, the position of the vehicle 90 can be measured with higher accuracy than when the positioning calculation is performed using the observation pseudo distance ρ.

Further, when the reception accuracy deteriorates due to multipath or the like for some satellites for a certain period of time, the distance ρ _{−1 serving as} the reference of the estimated pseudorange ρ # uses the ADR for the satellite. It is based on the positioning result estimated in the above. For this reason, the position of the vehicle 90 can be more reliably determined as compared with the case where the estimated pseudo distance ρ # is obtained simply by adding the amount of change in ADR to the observed pseudo distance ρ.

  According to the moving body position measuring apparatus 2 of the present embodiment described above, the position of the moving body can be determined more reliably and with high accuracy.

<Third embodiment>
Hereinafter, the mobile body positioning device 3 according to the third embodiment of the present invention will be described. FIG. 7 is a system configuration example of the mobile body positioning device 3 according to the third embodiment of the present invention. In addition to the configuration of the mobile body positioning device 1 of the first embodiment or the mobile body positioning device 2 of the second embodiment, the mobile body positioning device 3 includes a sub-positioning calculation unit 70 and a positioning result selection unit 72. And having. A description of other components is omitted.

Secondary positioning operation unit 70 on the basis of the Doppler frequency change amount Δf and GPS satellite 10 ₁ of the velocity vector V1, and calculates the velocity vector V of the vehicle 90. Specifically, first, based on the Doppler frequency change Delta] f, the relative velocity vector of the vehicle 90 as viewed from the GPS satellite 10 ₁ (V-V1), for example, calculated using the following equation (4). Wherein, V1 represents the velocity vector of the GPS satellites 10 _one.

Then, a relative velocity vector of the vehicle 90 as viewed from the GPS satellite 10 ₁ (V-V1), based on the velocity vector V1 of the GPS satellites 10 ₁ calculates the velocity vector V of the vehicle 90. That is, the difference vector of the relative velocity vector of the GPS satellite 10 ₁ and (V-V1) and GPS satellite 10 ₁ of the velocity vector V1, is calculated as the velocity vector V of the vehicle 90. Velocity vector V1 of the GPS satellites 10 ₁ is calculated in accordance with the time of calculating the position of the GPS satellite 10 _1.

  When the speed vector V of the vehicle 90 is calculated in this way, the sub-positioning calculation unit 70 performs a positioning calculation using a movement amount based on the speed vector V (a value obtained by multiplying the speed vector V by a positioning calculation period). Such positioning calculation adds the amount of movement based on the velocity vector V to the previous position (Xu (i-1), Yu (i-1), Zu (i-1)) of the vehicle 90 to determine the vehicle 90 of this time. The position (Xu (i), Yu (i), Zu (i)) is obtained.

  The positioning result selection unit 72 determines which one of the positioning result by the positioning calculation unit 60 described in the first embodiment or the second embodiment and the positioning result by the sub-positioning calculation unit 70 is highly accurate. Then, the positioning result determined to have higher accuracy is output as the current positioning result.

  Since various methods are already known for the accuracy determination method, detailed description thereof is omitted. For example, determination based on the residual of the least square method is performed.

  FIG. 8 is a flowchart showing a flow of characteristic processing executed by the positioning result selection unit 72 according to the third embodiment of the present invention. This flow is repeatedly executed with a predetermined cycle (synchronized with the positioning cycle of the positioning calculation unit 60 and the sub-positioning calculation unit 70).

  First, the positioning result selection unit 72 determines which one of the positioning result by the positioning calculation unit 60 and the positioning result by the sub-positioning calculation unit 70 is highly accurate (S400).

  When it is determined that the positioning result by the positioning calculation unit 60 is highly accurate, the positioning result by the positioning calculation unit 60 is selected and output (S402).

  On the other hand, when it is determined that the positioning result by the sub-positioning calculation unit 70 is highly accurate, the positioning result by the sub-positioning calculation unit 70 is selected and output (S404).

  The effect obtained by such processing is the same as that of the first embodiment or the second embodiment.

  According to the mobile body positioning device 3 of the present embodiment described above, the position of the mobile body can be measured more reliably and with high accuracy.

  The best mode for carrying out the present invention has been described above with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the present invention. And substitutions can be added.

  For example, in the first to third embodiments, when there is no previous positioning result used by the estimated pseudo-range calculation unit 50 or the sub-positioning calculation unit 70 (the situation is that the signal from the satellite travels completely in the tunnel). May occur after the power is shut off), the result of the vehicle position calculation based on the output of the vehicle sensor 80 may be regarded as the previous positioning result. In this way, the positioning of the moving body position can be resumed promptly.

  The present invention can be used in the automobile manufacturing industry, the automobile parts manufacturing industry, and the like.

1 is a system configuration diagram showing an overall configuration of a GNSS (Global Navigation System) to which a mobile body positioning device according to the present invention is applied. 1 is a system configuration example of a mobile body positioning device 1 according to a first embodiment of the present invention. It is a figure which shows a mode that a world coordinate system is defined. It is a flowchart which shows the flow of the characteristic process performed by the estimation pseudo distance calculation part 50 which concerns on 1st Example of this invention. It is a flowchart which shows the flow of the characteristic process performed by the positioning calculating part 60 which concerns on 1st Example of this invention. It is a flowchart which shows the flow of the characteristic process performed by the positioning calculating part 60 which concerns on 2nd Example of this invention. It is an example of a system configuration | structure of the mobile body positioning device 3 which concerns on 3rd Example of this invention. It is a flowchart which shows the flow of the characteristic process performed by the positioning result selection part 72 which concerns on 3rd Example of this invention.

Explanation of symbols

1, 2, 3 Mobile positioning device 10 GPS satellite 20 GPS antenna 30 Information processing device 40 Observation pseudorange calculation unit 50 Estimated pseudorange calculation unit 60 Positioning calculation unit 70 Sub-positioning calculation unit 72 Positioning result selection unit 80 Vehicle sensor 90 vehicle

Claims (4)

Receiving means for receiving signals from a plurality of satellites;
Observation pseudorange calculation means for calculating an observation pseudorange based on the signal received by the reception means;
Positioning calculation means for repeatedly performing positioning calculation based on the observation pseudo distance calculated by the observation pseudo distance calculation means;
A mobile body positioning device comprising:
An estimated pseudo-distance that calculates an estimated pseudo-range by adding an amount of change in ADR (Accumulated Doppler Range) to the distance obtained from the positioning result obtained previously and the satellite position while the positioning calculation means repeatedly performs positioning calculations. A calculation means,
The positioning calculation means performs a positioning calculation using the estimated pseudo distance calculated by the estimated pseudo distance calculation means instead of the observation pseudo distance calculated by the observation pseudo distance calculation means in a predetermined case. To
Mobile positioning device. Receiving means for receiving signals from a plurality of satellites;
Observation pseudorange calculation means for calculating an observation pseudorange based on the signal received by the reception means;
Positioning calculation means for repeatedly performing positioning calculation based on the observation pseudo distance calculated by the observation pseudo distance calculation means;
A mobile body positioning device comprising:
An estimated pseudo-distance that calculates an estimated pseudo-range by adding an amount of change in ADR (Accumulated Doppler Range) to the distance obtained from the positioning result obtained previously and the satellite position while the positioning calculation means repeatedly performs positioning calculations. A calculation means,
The positioning calculation means determines whether or not the reception accuracy of a satellite capable of receiving a signal is low, and the satellite determined to have low reception accuracy is replaced with the observation pseudorange calculated by the observation pseudorange calculation means. The positioning calculation is performed using the estimated pseudo distance calculated by the estimated pseudo distance calculating means,
Mobile positioning device. Sub-positioning calculation means for performing positioning calculation based on the vehicle speed vector;
Positioning result selection means for performing accuracy determination between the positioning result measured by the positioning calculation means and the positioning result measured by the sub-positioning calculation means, and selecting any positioning result based on the accuracy determination result When,
A mobile body positioning device according to claim 1 or 2, comprising: A moving amount calculating means for calculating the moving amount of the moving body based on the behavior of the moving body;
The estimated pseudo distance calculation means regards the positioning result using the movement amount calculated by the movement amount calculation means as the positioning result measured last time when there is no positioning result measured last time. Is a means for calculating the estimated pseudorange,
The mobile body positioning device according to any one of claims 1 to 3.

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