JP2010256301A - Multipath determination device and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To highly precisely determine whether a received signal from a GPS satellite is of a multipath, with a simple configuration. <P>SOLUTION: A GPS information acquisition part 20 receives radio waves from the GPS satellite. In addition, the GPS information acquisition part 20 acquires information of the GPS satellite and a phase difference between received signals from GPS antennas 12A, 12B. An incoming wave relative direction estimation part 24 estimates a relative incoming direction of radio waves from each GPS satellite, based on a phase difference between received signals from the GPS satellite. An incoming wave absolute direction estimation part 22 calculates each of absolute incoming directions of radio waves from each GPS satellite, based on information of the GPS satellite. A multipath determination part 26 determines whether or not a received signal from the estimated GPS satellite is a multipath, by wholly comparing a relative incoming direction of radio waves from the estimated GPS satellite with an absolute incoming direction of radio waves from the calculated GPS satellite. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a multipath determination device and a program, and more particularly, to a multipath determination device and a program for determining whether or not a received signal from a GPS satellite is a multipath.

  Conventionally, a signal arrival direction estimation device that estimates an arrival signal direction by a MUSIC method or the like is known (Patent Document 1). This apparatus multiplies the signal from each element antenna by a complex weight to make the directivity pattern of the m array antenna a desired shape, and performs highly accurate positioning based only on the desired wave.

JP-A-2005-77376

  However, the technique described in Patent Document 1 has a problem that the configuration of the apparatus becomes complicated because it is necessary to form an array with an antenna in order to control directivity.

  The present invention has been made in order to solve the above-described problems, and a multipath determination device capable of accurately determining whether or not a received signal from a GPS satellite is a multipath with a simple configuration, and The purpose is to provide a program.

  In order to achieve the above object, a multipath determination device according to a first aspect of the present invention is a GPS reception unit including a plurality of antennas for receiving radio waves from a GPS satellite, and the GPS satellites received by the GPS reception unit. Acquisition means for acquiring the information and the phase difference between the received signals from the GPS satellites received by each of the plurality of antennas for all of the GPS satellites that have received the radio waves, and acquisition for each GPS satellite by the acquisition means Relative direction estimation means for estimating the relative arrival directions of radio waves from the GPS satellites based on the phase difference of the received signals from the GPS satellites, and the GPS acquired by the acquisition means for each GPS satellite Absolute direction calculation means for calculating the absolute direction of arrival of radio waves from the GPS satellite based on the satellite information; By comparing the relative arrival direction of the radio wave from each GPS satellite estimated by the direction estimation unit and the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculation unit as a whole And determining means for determining whether or not the received signal from each GPS satellite is multipath.

  According to a second aspect of the invention, there is provided a program for receiving information on the GPS satellite received by a GPS receiving unit having a plurality of antennas for receiving radio waves from a GPS satellite, and the GPS received by each of the plurality of antennas. The acquisition means for acquiring the phase difference of the received signal from the satellite for all the GPS satellites that have received the radio wave, for each GPS satellite, based on the phase difference of the received signal from the GPS satellite acquired by the acquisition means, Relative direction estimation means for estimating the relative directions of arrival of radio waves from the GPS satellites, and for each GPS satellite, based on the information of the GPS satellites acquired by the acquisition means, the absolute of radio waves from the GPS satellites Each of the GPS satellites estimated by the absolute direction calculating means for calculating the respective arrival directions and the relative direction estimating means. By comparing the relative arrival direction of the radio waves from the GPS and the absolute arrival direction of the radio waves from each GPS satellite calculated by the absolute direction calculation unit as a whole, the received signal from each GPS satellite can be It is a program for functioning as determination means for determining whether or not each path.

  According to the first invention and the second invention, the radio wave from the GPS satellite is received by the GPS receiving means having a plurality of antennas. The acquisition unit acquires the GPS satellite information received by the GPS reception unit and the phase difference between the reception signals from the GPS satellites received by each of the plurality of antennas for all the GPS satellites that have received the radio waves.

  Then, the relative direction estimation means estimates the relative arrival direction of the radio wave from each GPS satellite based on the phase difference of the received signal from the GPS satellite acquired by the acquisition means. Further, the absolute direction calculation means calculates the absolute arrival direction of the radio wave from each GPS satellite based on the information of the GPS satellite acquired by the acquisition means.

  Then, the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation unit and the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculation unit are determined by the determination unit. By comparing as a whole, it is determined whether the received signal from each GPS satellite is multipath or not.

  In this way, each GPS satellite calculated from GPS information by estimating the relative direction of arrival of radio waves from each GPS satellite using the phase difference of the received signals from the GPS satellites received by each of the plurality of antennas. By comparing with the absolute direction of arrival of radio waves from, it is possible to accurately determine whether or not the received signal from the GPS satellite is multipath with a simple configuration.

  According to a third aspect of the present invention, there is provided a multipath determination apparatus comprising: a GPS receiving unit including a plurality of antennas for receiving radio waves from GPS satellites; information on the GPS satellites received by the GPS receiving unit; and the plurality of antennas. Acquisition means for acquiring the phase difference of the received signals from the GPS satellites received by each of all the GPS satellites that have received the radio waves, and the received signals from the GPS satellites acquired by the acquiring means for each GPS satellite Based on the phase difference of the GPS satellite, relative direction estimation means for estimating the relative direction of arrival of radio waves from the GPS satellite, and for each GPS satellite, based on the position information of the GPS satellite acquired by the acquisition means, Absolute direction calculation means for calculating the absolute direction of arrival of radio waves from the GPS satellite, and the absolute reference direction of the host vehicle Vehicle direction estimation means, a relative arrival direction of radio waves from each GPS satellite estimated by the relative direction estimation means, and an absolute reference direction of the vehicle estimated by the vehicle direction estimation means By comparing the absolute arrival direction of the radio wave from each GPS satellite and the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculating unit for each GPS satellite, And determining means for determining whether or not the received signal from each GPS satellite is multipath.

  According to a fourth aspect of the present invention, there is provided a program for receiving information on the GPS satellite received by a GPS receiver having a plurality of antennas for receiving radio waves from a GPS satellite, and the GPS received by each of the plurality of antennas. The acquisition means for acquiring the phase difference of the received signal from the satellite for all the GPS satellites that have received the radio wave, for each GPS satellite, based on the phase difference of the received signal from the GPS satellite acquired by the acquisition means, Relative direction estimation means for estimating the relative direction of arrival of radio waves from the GPS satellites, and for each GPS satellite, based on the positional information of the GPS satellites acquired by the acquisition means, the absolute radio waves from the GPS satellites Absolute direction calculating means for calculating the respective arrival directions, own vehicle direction estimating hand for estimating the absolute reference direction of the own vehicle And each GPS satellite obtained from the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimating means and the absolute reference direction of the own vehicle estimated by the own vehicle direction estimating means. Reception from each GPS satellite by comparing the absolute arrival direction of the radio wave from the GPS and the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculation means. This is a program for functioning as determination means for determining whether or not a signal is multipath.

  According to the third and fourth aspects of the invention, the radio wave from the GPS satellite is received by the GPS receiving means having a plurality of antennas. The acquisition unit acquires the GPS satellite information received by the GPS reception unit and the phase difference between the reception signals from the GPS satellites received by each of the plurality of antennas for all the GPS satellites that have received the radio waves.

  Then, the relative direction estimation means estimates the relative arrival direction of the radio wave from each GPS satellite based on the phase difference of the received signal from the GPS satellite acquired by the acquisition means. The absolute direction calculation means calculates, for each GPS satellite, the absolute arrival direction of the radio wave from the GPS satellite based on the position information of the GPS satellite acquired by the acquisition means. An absolute reference direction of the host vehicle is estimated by the host vehicle direction estimating means.

  Then, the determination means obtains the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation means and the absolute reference direction of the own vehicle estimated by the own vehicle direction estimation means, By comparing the absolute arrival direction of the radio wave from the GPS satellite and the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculating means for each GPS satellite, It is determined whether or not the received signal is multipath.

  In this way, the relative arrival direction of the radio wave from each GPS satellite is estimated using the phase difference of the received signals from the GPS satellites received by each of the plurality of antennas, and the absolute value of the estimated own vehicle is estimated. By estimating the absolute arrival direction of the radio wave from each GPS satellite from the reference direction, and comparing with the absolute arrival direction of the radio wave from each GPS satellite calculated from the GPS information, It is possible to accurately determine whether or not the received signal from the GPS satellite is multipath.

  According to a fifth aspect of the present invention, there is provided a multipath determination device comprising: a GPS receiving unit having a plurality of antennas for receiving radio waves from GPS satellites; position information of the GPS satellites received by the GPS receiving unit; and the plurality of antennas Acquisition means for acquiring the phase difference of the received signals from the GPS satellites received by each of all the GPS satellites that received the radio waves, and reception from the GPS satellites acquired by the acquisition means for each GPS satellite Based on the phase difference of the signal, relative direction estimating means for estimating the relative arrival direction of the radio wave from the GPS satellite, and for each GPS satellite, based on the position information of the GPS satellite acquired by the acquiring means Absolute direction calculation means for calculating the absolute direction of arrival of radio waves from the GPS satellite, and the absolute reference direction of the host vehicle The vehicle direction estimation means to estimate, the relative arrival direction of the radio waves from each GPS satellite estimated by the relative direction estimation means, and the absolute of the radio waves from each GPS satellite calculated by the absolute direction calculation means By comparing each GPS satellite with the relative arrival direction of the radio wave from each GPS satellite, which is obtained from the absolute arrival direction and the absolute reference direction of the own vehicle estimated by the own vehicle direction estimating means. And determining means for determining whether or not the received signal from each GPS satellite is multipath.

  According to a sixth aspect of the present invention, there is provided a program according to a position information of the GPS satellite received by a GPS receiving unit including a plurality of antennas for receiving radio waves from the GPS satellite, and the GPS satellite received by each of the plurality of antennas. Acquisition means for acquiring the phase difference of the received signal for all GPS satellites that have received the radio wave, and for each GPS satellite, based on the phase difference of the received signal from the GPS satellite acquired by the acquisition means, the GPS Relative direction estimation means for estimating the relative arrival directions of radio waves from the satellites, and for each GPS satellite, based on the position information of the GPS satellites acquired by the acquisition means, the absolute radio wave from the GPS satellites Absolute direction calculating means for calculating each direction of arrival, own vehicle direction estimating means for estimating an absolute reference direction of the own vehicle, and Relative arrival direction of radio waves from each GPS satellite estimated by the counter direction estimation means, absolute arrival direction of radio waves from each GPS satellite calculated by the absolute direction calculation means, and estimation of the direction of the own vehicle By comparing the relative arrival directions of the radio waves from the respective GPS satellites obtained from the absolute reference direction of the host vehicle estimated by the means, the received signals from the respective GPS satellites are multiplexed. It is a program for functioning as determination means for determining whether or not each path.

  According to the fifth and sixth aspects of the invention, the radio wave from the GPS satellite is received by the GPS receiving means having a plurality of antennas. The acquisition unit acquires the GPS satellite information received by the GPS reception unit and the phase difference between the reception signals from the GPS satellites received by each of the plurality of antennas for all the GPS satellites that have received the radio waves.

  Then, the relative direction estimation means estimates the relative arrival direction of the radio wave from each GPS satellite based on the phase difference of the received signal from the GPS satellite acquired by the acquisition means. The absolute direction calculation means calculates, for each GPS satellite, the absolute arrival direction of the radio wave from the GPS satellite based on the position information of the GPS satellite acquired by the acquisition means. An absolute reference direction of the host vehicle is estimated by the host vehicle direction estimating means.

  And the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation unit by the determination unit, the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculation unit, and By comparing the relative arrival direction of the radio wave from each GPS satellite, which is obtained from the absolute reference direction of the own vehicle estimated by the own vehicle direction estimation means, for each GPS satellite, It is determined whether or not the received signal is multipath.

  Thus, using the phase difference of the received signals from the GPS satellites received by each of the plurality of antennas, the relative arrival directions of the radio waves from the respective GPS satellites are estimated, and the absolute value of the estimated own vehicle is estimated. By comparing the reference direction and the relative arrival direction of the radio wave from each GPS satellite obtained from the absolute arrival direction of the radio wave from each GPS satellite calculated from the GPS information, the GPS can be obtained with a simple configuration. It is possible to accurately determine whether the received signal from the satellite is multipath or not.

  The acquisition means according to the third and fifth aspects of the present invention provides the position information of the GPS satellite, the phase difference of the received signal from the GPS satellite, and the Doppler frequency of the received signal from the GPS satellite, of the GPS satellite that has received the radio wave. The vehicle direction estimation means is obtained for all, and includes a relative speed calculation means for calculating a relative speed of the own vehicle with respect to each GPS satellite based on each of the Doppler frequencies acquired by the acquisition means. Using the calculated relative speed, the absolute reference direction of the host vehicle can be estimated.

  The own vehicle direction estimating means including the relative speed calculating means calculates the speed of each GPS satellite from the acquired GPS satellite information, and calculates the relative speed for each GPS satellite calculated by the relative speed calculating means. And the vehicle speed calculation means for calculating the speed of the vehicle in each GPS satellite direction based on the calculated speed of each GPS satellite, and the vehicle speed based on the calculated speed of the vehicle in each GPS satellite direction. A speed vector estimation unit that estimates a speed vector of the vehicle is further provided, and an absolute reference direction of the host vehicle can be estimated based on the speed vector of the host vehicle estimated by the speed vector estimation unit.

  The multipath determination device according to the third and fifth aspects of the present invention further includes a position calculating means for calculating the position of the own vehicle, and the own vehicle direction estimating means is configured to calculate the position from the road map information stored in advance. It is possible to acquire the direction of the road where the position of the host vehicle calculated by (1) exists and to estimate the absolute reference direction of the host vehicle based on the acquired direction of the road. Thus, the absolute reference direction of the host vehicle can be estimated by simple processing.

  The vehicle direction estimation means including the above relative speed calculation means calculates the speed of each GPS satellite from the acquired GPS satellite information, and calculates the relative speed and the relative speed for each GPS satellite calculated by the relative speed calculation means. Based on at least two GPS satellites, the own vehicle speed calculating means for calculating the speed of the own vehicle in the direction of each GPS satellite, the vehicle speed acquiring means for acquiring the vehicle speed of the own vehicle, and the speed of each GPS satellite. Speed vector estimating means for estimating the speed vector of the own vehicle based on the obtained speed of the own vehicle in each GPS satellite direction and the acquired vehicle speed of the own vehicle, and estimated by the speed vector estimating means Based on the speed vector of the host vehicle, the absolute reference direction of the host vehicle can be estimated. This makes it possible to estimate the absolute reference direction of the host vehicle even when the number of GPS satellites that have received radio waves is small.

  The vehicle direction estimation means including the above relative speed calculation means calculates the speed of each GPS satellite from the acquired GPS satellite information, and calculates the relative speed and the relative speed for each GPS satellite calculated by the relative speed calculation means. The vehicle speed calculation means for calculating the speed of the own vehicle in the direction of each GPS satellite, the vehicle speed acquisition means for acquiring the vehicle speed of the own vehicle, and the change of the clock bias with time Clock bias drift calculating means for calculating a clock bias drift indicating the ratio of the vehicle, the speed of the host vehicle in the direction of the GPS satellite calculated for at least one GPS satellite, the obtained vehicle speed of the host vehicle, and the calculated clock bias Speed vector estimating means for estimating the speed vector of the host vehicle based on the drift, and the speed vector estimating means Ri based on the velocity vector of the estimated vehicle, it is possible to estimate the absolute reference direction of the vehicle. This makes it possible to estimate the absolute reference direction of the host vehicle even when the number of GPS satellites that have received radio waves is small.

  The multipath determination device described above receives a received signal from each GPS satellite based on whether or not there is a shield in the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation means. Second determination means for determining whether the path is multipath can be further included. As a result, it is possible to more accurately determine whether or not the received signal from the GPS satellite is multipath.

  The multipath determination device including the second determination unit further includes an imaging unit that images the surroundings of the host vehicle, and a shielding object detection unit that detects the shielding object from the image captured by the imaging unit. 2 determination means can determine whether there is a shield in the relative arrival direction of the radio wave from each estimated GPS satellite based on the detection result of the shield detection means.

  The multipath determination device including the second determination unit further includes a position calculation unit that calculates the position of the host vehicle, and the shielding unit determination unit is calculated by the position calculation unit from road map information stored in advance. It is possible to acquire the presence or absence of a shielding object around the position of the host vehicle and determine whether or not there is a shielding object in the estimated relative arrival direction of the radio wave from each GPS satellite.

  In the multipath determination device described above, whether the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation unit is a predetermined direction in which a shielding object may be present. Based on the above, it is possible to further include second determination means for determining whether or not the received signal from each GPS satellite is multipath. As a result, it is possible to more accurately determine whether or not the received signal from the GPS satellite is multipath.

  Further, the acquisition means described above further calculates the GPS radio wave propagation time from when the radio wave is transmitted from the GPS satellite to the host vehicle, or the pseudo distance to the GPS satellite, for each of the GPS satellites that have received the radio wave. The multipath determination device obtains each GPS satellite by comparing the difference in GPS radio wave propagation time between antennas or the difference in pseudo distance with the phase difference of the received signal from the GPS satellite. Third determination means for determining whether or not the received signal from the satellite is multipath can be further included. As a result, it is possible to more accurately determine whether or not the received signal from the GPS satellite is multipath.

  The acquisition means further acquires the Doppler frequency of the received signal from the GPS satellite for each of the GPS satellites that have received the radio wave, and based on the difference in Doppler frequency between the antennas in each GPS satellite, Fourth determination means for determining whether or not the received signal from each GPS satellite is multipath can be further included. As a result, it is possible to more accurately determine whether or not the received signal from the GPS satellite is multipath.

  The GPS reception means includes three or more antennas, and the relative direction estimation means, for each GPS satellite, based on the phase difference between the antennas of the received signals from the GPS satellites acquired by the acquisition means, The relative arrival directions represented by the elevation angle and the azimuth angle of the radio waves from the GPS satellites are each estimated, and the absolute direction calculation means for each GPS satellite based on the GPS satellite information acquired by the acquisition means, Absolute arrival directions represented by elevation and azimuth of radio waves from the GPS satellites can be calculated. As a result, it is possible to more accurately determine whether or not the received signal from the GPS satellite is multipath.

  The acquisition means further acquires the GPS radio wave propagation time from when the radio wave is transmitted from the GPS satellite until it reaches the host vehicle or the pseudo distance to the GPS satellite for all the GPS satellites that have received the radio wave. The determination device further includes position calculation means for calculating the position of the host vehicle based on the GPS radio wave propagation time or the pseudorange of each GPS satellite other than the GPS satellite determined to be a multipath received signal. Can do. Thereby, the position of the own vehicle can be calculated with high accuracy.

  The program according to the present invention can be provided by being stored in a storage medium.

  As described above, according to the multipath determination device and the program of the present invention, the relative difference of the radio wave from each GPS satellite is obtained using the phase difference of the received signal from the GPS satellite received by each of the plurality of antennas. By estimating the arrival direction and comparing it with the absolute arrival direction or relative arrival direction of the radio wave from each GPS satellite calculated from GPS information, the received signal from the GPS satellite can be multiplexed with a simple configuration. It is possible to determine whether or not the path is accurate.

It is a block diagram which shows the vehicle-mounted measuring apparatus which concerns on the 1st Embodiment of this invention. It is an image figure which shows a mode that the arrival direction of an electromagnetic wave is estimated from the phase difference of the received signal between GPS antennas. It is an image figure which shows a mode that the position of the own vehicle is estimated according to the principle of triangulation. (A) The figure which shows the absolute arrival direction of the electromagnetic wave calculated from the satellite position, (B) The figure which shows the relative arrival direction of the estimated electromagnetic wave. It is a flowchart which shows the content of the multipath determination processing routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the vehicle-mounted measuring apparatus which concerns on the 2nd Embodiment of this invention. It is an image figure which shows a mode that the speed of each GPS satellite of the own vehicle direction is calculated based on the velocity vector of each GPS satellite, and the direction of each GPS satellite. It is a flowchart which shows the content of the multipath determination processing routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the content of the own vehicle direction estimation process routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the vehicle-mounted measuring apparatus which concerns on the 3rd Embodiment of this invention. It is a flowchart which shows the content of the own vehicle direction estimation process routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 3rd Embodiment of this invention. It is a flowchart which shows the content of the own vehicle direction estimation process routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 4th Embodiment of this invention. It is a flowchart which shows the content of the own vehicle direction estimation process routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 5th Embodiment of this invention. It is a block diagram which shows the vehicle-mounted measuring apparatus which concerns on the 6th Embodiment of this invention. It is a flowchart which shows the content of the 2nd multipath determination processing routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 6th Embodiment of this invention. It is a block diagram which shows the vehicle-mounted measuring apparatus which concerns on the 7th Embodiment of this invention. It is a flowchart which shows the content of the 2nd multipath determination processing routine in the computer of the vehicle-mounted measuring device which concerns on the 7th Embodiment of this invention. It is a block diagram which shows the vehicle-mounted measuring apparatus which concerns on the 8th Embodiment of this invention. It is a figure which shows a mode that a direct wave and a reflected wave are received with two GPS antennas. It is a flowchart which shows the content of the 2nd multipath determination processing routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 8th Embodiment of this invention. It is a flowchart which shows the content of the 3rd multipath determination processing routine in the computer of the vehicle-mounted measuring apparatus which concerns on the 8th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the case where this invention is applied to the vehicle-mounted measuring apparatus mounted in a vehicle and measuring the position of the own vehicle is demonstrated to an example.

  As shown in FIG. 1, the in-vehicle measuring apparatus 10 according to the first embodiment includes a GPS receiving unit 12 that receives radio waves from a GPS satellite, and a received signal from the GPS satellite that is received by the GPS receiving unit 12. And a computer 14 that measures the position of the host vehicle and determines whether or not the received signal is multipath.

  The GPS receiving unit 12 includes two or more GPS antennas 12A and 12B that receive radio waves from GPS satellites, and each of the GPS antennas 12A and 12B receives radio waves from the GPS satellites. The GPS receiving unit 12 receives radio waves from a plurality of GPS satellites, and from the received signals from all the received GPS satellites, as GPS satellite information, the satellite number, the carrier phase, and the code pseudo distance of the GPS satellite. The Doppler shift frequency, signal intensity, and orbit information are acquired and output to the computer 14. The received signal is output for each of the GPS antennas 12A and 12B. Further, the distance between the GPS antennas 12A and 12B is known.

  The computer 14 includes a storage device such as a CPU, a ROM that stores a program for realizing a multipath determination processing routine that will be described later, a RAM that temporarily stores data, and an HDD.

  When the computer 14 is represented by functional blocks in accordance with a multipath determination processing routine described below, as shown in FIG. 1, GPS satellite information is acquired from the GPS receiver 12 for all GPS satellites that have received radio waves. Based on the GPS information acquisition unit 20 that acquires the phase difference of the received signals between the GPS antennas 12A and 12B, and the calculated position of the own vehicle and the position coordinates of each GPS satellite, the absolute radio wave from each GPS satellite is obtained. Based on the obtained phase difference between the GPS antennas 12A and 12B of each GPS satellite, the arrival direction for estimating the relative direction of arrival of the radio wave from each GPS satellite based on the obtained phase difference between the GPS antennas 12A and 12B. The relative wave direction estimation unit 24, the estimated relative arrival direction of the radio waves from each GPS satellite, and the absolute radio wave from each GPS satellite calculated A multipath determination unit 26 that determines whether or not a received signal from each GPS satellite is a multipath by comparing the incoming directions as a whole, and a GPS pseudo distance of a received signal other than a GPS satellite that is determined to be a multipath A host vehicle position calculation unit 28 that calculates the position of the host vehicle based on the data is provided.

  The GPS information acquisition unit 20 acquires GPS satellite information for all GPS satellites that have received radio waves from the GPS reception unit 12, and based on reception signals received by the GPS antennas 12A and 12B, The phase difference between 12A and 12B is calculated. Further, the position of the GPS satellite and the transmission time at which the GPS satellite transmits radio waves are estimated and acquired based on the GPS satellite information acquired from the received signal. For example, the GPS position is a function of time, and a coefficient that determines the function is acquired as “orbit information”, and the GPS position is estimated and acquired based on the orbit information. Needless to say, GPS satellite information and the phase difference between the GPS antennas 12A and 12B are not acquired for GPS satellites whose received radio waves have a low input level, a low SN signal, or the like.

The incoming wave absolute direction calculation unit 22 is based on the position of the own vehicle calculated by the own vehicle position calculation unit 28 and the position coordinates of each GPS satellite, and the angular relationship between the position of each GPS satellite j and the position of the own vehicle. (Elevation angle θ _j with respect to the horizontal plane and azimuth angle φ _{j with} respect to the north direction on the horizontal plane) are estimated as absolute directions of arrival of radio waves from the respective GPS satellites.

  As shown in FIG. 2, the incoming wave relative direction estimation unit 24 is based on the phase difference of the received signal between the GPS antennas 12A and 12B calculated for each GPS satellite and the distance L between the GPS antennas 12A and 12B. The relative arrival direction of the radio wave from each GPS satellite with respect to the antenna installation direction (reference direction) is estimated. The arrival wave relative direction estimation unit 24 corrects the elevation angle of the absolute arrival direction estimated by the arrival wave absolute direction calculation unit 22 and estimates the relative arrival direction as an azimuth angle on the horizontal plane. To do.

  Next, the principle of the present invention will be described.

  In the positioning using GPS, as shown in FIG. 3, the position of the host vehicle is estimated by the principle of triangulation from the known GPS satellite position and the pseudo distance that is the propagation distance of the signal received from each satellite. .

  The pseudorange is calculated from the propagation time. The propagation time includes errors due to tropospheric delay, ionospheric delay, clock bias, and the like, and the pseudorange is expressed by the following equation (1).

However, ^{t R} is the reception time of the GPS receiver including an error, ^{t r} is the received time for a precise GPS ^{time, t} _{t j} is transmitted from a GPS satellite j at the exact GPS time It's time. R _j is a true distance from the GPS satellite j, B _j is a distance error due to a clock error of the GPS satellite j, and S is a distance error due to a clock error (clock bias) of the GPS receiver. Further, I _j is a distance error from the GPS satellite j due to ionospheric delay, t _j is a distance error from the GPs satellite j due to tropospheric delay, and ξ _j is other errors such as multipath.

  Further, since the GPS satellite position is also a function of time, when the propagation time includes an error, the GPS satellite position is also calculated including the error. Here, the optimal estimation using pseudorange described in non-patent literature (Takayasu Sakai, “Practical programming for GPS”, Tokyo Denki University Press, 2007.) is generally used for positioning. It is.

  In this optimal estimation, a signal from a GPS satellite having a large pseudorange residual is removed as a multipath to improve estimation accuracy. In general, signal strength and the like are used in addition to pseudoranges for multipath determination, and the position and velocity are estimated relatively stably under a situation where the number of visible satellites is large.

  However, when many signals including not only direct waves but also reflected waves and diffracted waves are received as in the central area, the pseudorange may include a large error. When there is a large error in the pseudorange, the positioning error becomes large. In this case, the estimation error of the propagation time is also large, and an error occurs even in the calculation of the GPS satellite position. At this time, since the GPS satellite position also includes an error, the multipath determination using the pseudorange residual cannot be determined with sufficient accuracy. In addition, when the reflection point of the signal in the multipath is close to the GPS receiver, a path difference due to the multipath hardly occurs, and it is difficult to determine the multipath with the pseudorange residual.

  Therefore, in the present embodiment, the estimated arrival direction of the radio wave from each GPS satellite is compared with the original arrival direction, and if they do not match, it is determined as multipath.

  Here, since the satellite direction is known when estimating the original arrival wave direction, the direction in which the satellite exists can be calculated, but the satellite direction is predicted based on the antenna installation direction on which the GPS receiver is mounted. In order to do so, it is necessary to estimate the direction of the moving object.

  When there are two or more GPS antennas whose distance between the antennas is known, the direction can be determined from the difference between the positioning results and the distance between the antennas. Further, in a method generally used in a GPS compass or the like, the direction of the moving body can be determined with the incoming wave direction estimated from the phase difference between the antennas as the satellite direction as it is. However, in an environment with many multipaths, it is not easy to determine the azimuth of a moving object only from the phase and positioning position.

  Therefore, in the present embodiment, the multipath determination unit 26 does not directly estimate the azimuth of the moving body, and as shown in FIGS. Comparing the entire absolute arrival direction calculated from the satellite positional relationship with the entire relative arrival wave direction estimated by the arrival wave relative direction estimation unit 24 as a whole, the satellites whose arrival directions do not match (see FIG. Multipaths are determined by estimating 4 SN4).

  The vehicle position calculation unit 28 will be described below using the GPS pseudorange data of each GPS satellite acquired by the GPS information acquisition unit 20 and the determination result of the multipath determination unit 26 as follows. Next, the position of the host vehicle is calculated.

First, the true distance r _j to the GPS satellite is expressed by the following equation (2), and the pseudo distance ρ _j observed by GPS is expressed by the following equation (3).

However, (X _j , Y _j , Z _j ) is the position coordinate of the GPS satellite j, and (x, y, z) is the position coordinate of the host vehicle. s is a distance error due to a clock error (clock bias) of the GPS receiver.

  From the above equations (2) and (3), by solving the simultaneous equations of the following equation (4) obtained from the GPS pseudorange data of four or more GPS satellites, the position of the host vehicle (x, y, z ) Is calculated.

  The own vehicle position calculation unit 28 excludes the pseudorange data of the GPS satellites for which the received signal is determined to be multipath from the pseudorange data obtained for all GPS satellites that have received radio waves, and the remaining GPS. The position (x, y, z) of the host vehicle is calculated by solving the simultaneous equations of the above formula (4) obtained by using the pseudorange data of the satellite, and the calculated position of the host vehicle is set to an external device (for example, , Navigation system and driving support system). However, since the GPS pseudo distance data and the determination result acquired by the GPS information acquisition unit 20 can be used not only for position estimation but also for two-dimensional positioning, it is not necessarily required to be data for four or more GPS satellites. No. Depending on the application, data about one GPS satellite may be used, and the usage destination is not limited to position estimation.

  Next, the operation of the in-vehicle measurement device 10 according to the first embodiment will be described.

  When the radio waves are received from a plurality of GPS satellites by the GPS antennas 12A and 12B of the GPS receiver 12, the multipath determination processing routine shown in FIG.

  First, in step 100, the information of a plurality of GPS satellites is acquired from the GPS receiver 12, and the phase difference of the received signals of the plurality of GPS satellites between the GPS antennas 12A and 12B is acquired.

  Then, in step 102, based on the position coordinates of each GPS satellite calculated based on the information of each GPS satellite acquired in step 100, and the vehicle position previously calculated in step 110 or step 112 described later. The direction of each GPS satellite is calculated as the absolute direction of arrival of radio waves from each GPS satellite.

  In the next step 104, based on the phase difference of the received signals from the GPS satellites between the GPS antennas 12A and 12B acquired in the above step 100, the radio wave from each GPS satellite based on the traveling direction of the host vehicle is used. Estimate the relative direction of arrival.

  In step 106, the absolute arrival direction of the radio wave from each GPS satellite calculated in step 102 and the relative arrival direction of the radio wave from each GPS satellite estimated in step 104 are taken as a whole. In comparison, it is determined whether or not the received signal from each GPS satellite is multipath based on whether or not the arrival directions match, and the determination result is output to the external device. The number of satellites used for the determination may be at least three.

  In the next step 108, it is determined whether or not there is a received signal from the GPS satellite determined to be multipath in step 106. If there are GPS satellites whose arrival directions of radio waves do not match when compared as a whole in step 106, except for the pseudorange data of the GPS satellites in which the received signal is determined to be multipath in step 110. Based on the pseudorange data of other GPS satellites acquired in step 100, the vehicle position is calculated and output to the external device, and the multipath determination processing routine is terminated.

  On the other hand, if the arrival directions of radio waves coincide for all GPS satellites when compared as a whole in step 106, there is no reception signal from the GPS satellites determined to be multipath in step 108. In step 112, based on the pseudorange data of each GPS satellite acquired in step 100, the vehicle position is calculated and output to the external device, and the multipath determination processing routine is terminated.

  As described above, according to the in-vehicle measurement device according to the first embodiment, the phase difference of the received signals from the GPS satellites received by each of the plurality of GPS antennas is used to Estimate the relative direction of arrival. By comparing with the original absolute arrival direction of the radio wave from each GPS satellite calculated using the known satellite position, the received signal from the GPS satellite is multipath with a simple configuration. It can be accurately determined whether or not there is.

  In addition, if the pseudo-range data of the signal from the wrong direction due to multipath is used, the positioning accuracy is reduced. Signals with errors can be removed, and positioning accuracy can be improved.

  Next, a second embodiment will be described. In addition, about the part which becomes the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the second embodiment, the traveling direction of the host vehicle is estimated, the absolute arrival directions of the radio waves from the respective GPS satellites are estimated, and the absolute arrival directions of the radio waves are compared with each other. This is mainly different from the first embodiment.

  As shown in FIG. 6, the computer 214 of the in-vehicle measurement device 210 according to the second embodiment acquires GPS satellite information for all GPS satellites that have received radio waves from the GPS receiver 12, and GPS A GPS information acquisition unit 220 that acquires a phase difference of received signals between the antennas 12A and 12B, an incoming wave absolute direction calculation unit 22, an incoming wave relative direction estimation unit 24, and the acquired Doppler shift frequency of each GPS satellite are used. The vehicle direction estimation unit 222 that estimates the absolute traveling direction (azimuth angle with respect to the north direction) as the reference direction of the host vehicle, the estimated absolute traveling direction of the host vehicle, and each estimated GPS Based on the relative arrival directions of the radio waves from the satellites, the arrival wave absolute direction estimation unit 224 that estimates the absolute arrival directions of the radio waves from the GPS satellites, The absolute arrival direction of the radio wave from the S satellite and the calculated absolute arrival direction of the radio wave from each GPS satellite are compared for each GPS satellite, and whether the received signal from each GPS satellite is multipath A multi-path determination unit 226 for determining whether or not the vehicle and a vehicle position calculation unit 28 are provided.

  The GPS information acquisition unit 220 acquires GPS satellite information for all GPS satellites that have received radio waves from the GPS reception unit 12, and calculates the phase difference between the GPS antennas 12A and 12B. The Doppler shift frequency included in the GPS satellite information is acquired based on the known frequency of the signal transmitted from each GPS satellite and the frequency of the received signal received from each GPS satellite. The Doppler shift frequency is obtained by observing the Doppler shift amount of the carrier frequency based on the relative speed between the GPS satellite and the own vehicle.

  The own vehicle direction estimation unit 222 estimates the absolute traveling direction of the own vehicle as described below.

  First, the relative speed of the host vehicle with respect to each GPS satellite is calculated from the Doppler shift frequency of the received signal from each GPS satellite according to the following equation (5) representing the relationship between the Doppler shift frequency and the relative speed with respect to the GPS satellite.

Here, v _j is a relative velocity with respect to the GPS satellite j, and D1 _j is a Doppler shift frequency (Doppler shift amount) obtained from the GPS satellite j. C is the speed of light, and F ₁ is a known L1 frequency of a signal transmitted from a GPS satellite.

Next, velocity vectors (three-dimensional velocities VX _j , VY _j , VZ _j ) of the respective GPS satellites are calculated from the obtained time series data of the position coordinates of the respective GPS satellites using differentiation of Kepler's equations. For example, using the method described in a non-patent document (Pratap Misra and Per Eng, the original Japanese Navigational Society GPS Study Group translation: “Sophisticated GPS Basic Concept / Positioning Principle / Signal and Receiver”, Shoyo Bunko, 2004.) The velocity vector of each GPS satellite can be calculated.

Further, as shown in FIG. 7, based on the calculated velocity vector (VX _j , VY _j , VZ _j ) of each GPS satellite and the direction (θ _j , φ _j ) of each GPS satellite, then calculate the velocity Vs _j of the GPS satellites, based on the speed Vs _j of the relative velocity _{v j} and each GPS satellite j of the vehicle direction of the vehicle with respect to each GPS satellite j, in accordance with the following equation (6), each calculate the velocity Vv _j direction of the vehicle of the GPS satellites j.

However, v _j is a relative speed of the own vehicle with respect to the GPS satellite j (relative speed with respect to the GPS satellite in the satellite direction), and Vs _j is a speed of the GPS satellite j in the direction of the own vehicle. Vv _j is the own vehicle speed in the direction of the GPS satellite j, and the dot Cb is clock bias drift.

  As described above, the own vehicle speed in the direction of the GPS satellite is calculated not only by the three-dimensional position of the GPS satellite position but only by the orientation relationship with the GPS satellite. The GPS satellite is far away, and the angle change per minute is 0.5 degrees because it makes two rounds of the earth in one day. Usually, since the clock error between the GPS satellite and the GPS receiver is at most several seconds, there is no significant influence on the orientation relationship with the GPS satellite. Similarly, since the GPS satellite is far away, even if an error of about several hundred meters occurs in determining the position of the own vehicle, the orientation relationship with the GPS satellite is not greatly affected. For this reason, even if it is a situation where an error is likely to ride on the pseudo distance, the vehicle speed in the direction of the GPS satellite can be accurately calculated as compared with the pseudo distance.

  Then, as described below, optimal estimation of the speed vector of the host vehicle is performed.

First, when the velocity vector of the vehicle and (Vx, Vy, Vz), the vehicle relationship between the speed Vv _j of the following equation (7) of the GPS satellite direction is expressed by equation (8).

  From the above equations (7) and (8) obtained for each GPS satellite j, simultaneous equations represented by the following equation (9) using the dots of Vx, Vy, Vz, and Cb as estimated values are obtained.

  For each combination of four GPS satellites, the speed vector (Vx, Vy, Vz) of the host vehicle is calculated by solving the simultaneous equations of the above formula (9), and the calculated speed vector of the host vehicle ( The optimum value of the speed vector of the host vehicle is estimated by obtaining a least square solution of (Vx, Vy, Vz).

  Then, the absolute traveling direction of the host vehicle is estimated based on the estimated direction of the speed vector of the host vehicle.

  Of the four unknowns, if the velocity vector in the vertical direction is set to “0”, the absolute traveling direction of the host vehicle can be estimated even with three or more GPS satellites. As the number of satellites increases, there is a possibility that a correct direction can be estimated. However, if there are at least three, the direction necessary for multipath determination can be estimated.

  As described above, the host vehicle direction estimation unit 222 calculates the speed of the host vehicle with respect to each GPS satellite direction using the Doppler shift frequency, and calculates the absolute speed of the host vehicle from the speed of the host vehicle with respect to each GPS satellite direction. Estimate the direction of travel.

  The arrival wave absolute direction estimation unit 224 uses the estimated absolute traveling direction of the host vehicle to estimate the relative arrival direction of the radio wave from each GPS satellite with respect to the estimated traveling direction of the host vehicle. It converts into the absolute arrival direction of the radio wave from a GPS satellite, and it is set as the estimated value of the absolute arrival direction of the radio wave from each GPS satellite.

  The multipath determination unit 226 compares the absolute arrival direction calculated from the satellite position and the estimated absolute arrival direction for each GPS satellite, and estimates a satellite that does not match the arrival direction. Determine multipath.

  Next, a multipath determination processing routine according to the second embodiment will be described with reference to FIG. In addition, about the process similar to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  First, in step 250, information on a plurality of GPS satellites is acquired from the GPS receiver 12, and the phase difference of received signals between the GPS antennas 12A and 12B is acquired.

  In step 102, the direction of each GPS satellite is calculated as the absolute direction of arrival of radio waves from each GPS satellite. In the next step 104, the direction from each GPS satellite is calculated based on the traveling direction of the host vehicle. Calculate the relative direction of arrival of radio waves.

  In step 252, the absolute traveling direction of the host vehicle is estimated using the Doppler shift frequency acquired in step 250.

  In the next step 254, each GPS satellite is based on the relative arrival direction of the radio wave from each GPS satellite estimated in step 104 and the absolute traveling direction of the vehicle estimated in step 252. Estimate the absolute direction of arrival of radio waves from. Then, in step 256, the absolute arrival direction of the radio wave from each GPS satellite calculated in step 102 and the absolute arrival direction of the radio wave from each GPS satellite estimated in step 254 are determined as GPS. Based on whether or not the arrival directions coincide with each other, it is determined whether or not the received signal from each GPS satellite is multipath, and the determination result is output to an external device.

  In the next step 108, it is determined whether there is a reception signal from the GPS satellite determined to be multipath in step 256. If there is a GPS satellite whose arrival direction of radio waves does not match when compared for each GPS satellite in step 256, the pseudo-range data of the GPS satellite determined in step 110 that the received signal is multipath. Except for the above, based on the pseudorange data of other GPS satellites acquired in step 100 above, the vehicle position is calculated and output to the external device, and the multipath determination processing routine is terminated.

  On the other hand, when the arrival directions of the radio waves coincide for all GPS satellites in step 256, it is determined in step 108 that there is no received signal from the GPS satellite determined to be multipath. Based on the pseudorange data of each GPS satellite acquired in step 100, the vehicle position is calculated and output to the external device, and the multipath determination processing routine is terminated.

  Step 252 is realized by the vehicle direction estimation processing routine shown in FIG. First, in step 270, based on the Doppler shift frequency in each GPS satellite acquired in step 250, the relative speed of the host vehicle with respect to each GPS satellite is calculated.

  In the next step 272, the velocity vector of each GPS satellite is calculated based on the GPS satellite position coordinates calculated based on the GPS satellite information acquired in step 250. In step 274, the above step 110 or In step 112, the vehicle position calculated last time is acquired.

  In step 276, the position of each GPS satellite is calculated based on the position coordinates of each GPS satellite calculated based on the information of each GPS satellite acquired in step 250 and the own vehicle position acquired in step 274. Calculate the direction. In step 278, based on the velocity vector of each GPS satellite calculated in step 272 and the direction of each GPS satellite calculated in step 276, for each GPS satellite, the velocity of the GPS satellite in the direction of the vehicle is calculated. Calculate each.

  In the next step 280, the vehicle speed in each GPS satellite direction is calculated based on the relative speed for each GPS satellite calculated in step 270 and the speed of each GPS satellite in the vehicle direction calculated in step 278. calculate.

  In step 282, the vehicle's speed vector is optimally estimated using the vehicle speed in each GPS satellite direction calculated in step 280. In step 284, the absolute traveling direction of the host vehicle is estimated based on the direction of the speed vector of the host vehicle estimated in step 282, and the host vehicle direction estimation processing routine is terminated.

  As described above, according to the in-vehicle measurement device according to the second embodiment, the phase difference of the received signals from the GPS satellites received by each of the plurality of GPS antennas is used to The relative arrival direction is estimated, and the absolute arrival direction of the radio wave from each GPS satellite is estimated from the estimated absolute reference direction of the own vehicle. By comparing the absolute arrival direction of the radio wave from each GPS satellite calculated using the known satellite position with each GPS satellite, the received signal from the GPS satellite is multipath with a simple configuration. It can be accurately determined whether or not there is.

  Next, a third embodiment will be described. In addition, about the part which becomes the same structure as 1st Embodiment and 2nd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The third embodiment is different from the second embodiment in that the absolute traveling direction of the host vehicle is estimated based on the direction of the road where the host vehicle position exists.

  As shown in FIG. 10, the computer 314 of the in-vehicle measurement device 310 according to the third embodiment includes a GPS information acquisition unit 20, an incoming wave absolute direction calculation unit 22, an incoming wave relative direction estimation unit 24, and a calculation. A host vehicle direction estimation unit 322 that estimates an absolute travel direction (azimuth angle) of the host vehicle based on the position of the host vehicle and road map data stored in a navigation system (not shown); An arrival wave absolute direction estimation unit 224, a multipath determination unit 226, and the position of the host vehicle are calculated based on GPS pseudorange data of a received signal other than a GPS satellite determined to be multipath, and a navigation system (illustrated) A vehicle position calculation unit 328 that performs map matching using the road map data stored in (omitted) and corrects the calculated position of the vehicle.

  The own vehicle position calculation unit 328 uses the information of each GPS satellite acquired by the GPS information acquisition unit 20 and the determination result of the multipath determination unit 226 in the same manner as in the first embodiment. The position of is calculated. The own vehicle position calculation unit 328 acquires road map data from the navigation system mounted on the own vehicle, determines whether or not the calculated position of the own vehicle is a position on the road, When the calculated position of the own vehicle is not on the road, map matching is performed so that the calculated position of the own vehicle becomes a position on the road, and the calculated position of the own vehicle is corrected. Thereby, even if the positioning position is largely deviated, display on the road can be appropriately performed by map matching. Note that a conventionally known method may be used as the map matching method, and detailed description thereof is omitted in the present embodiment.

  The host vehicle direction estimation unit 322 acquires road map data storing information including the position of the road from the navigation system mounted on the host vehicle, and the host vehicle position calculated by the host vehicle position calculation unit 328 Is estimated as the absolute traveling direction of the host vehicle. Note that which direction of the road on which the position of the host vehicle exists is set as the travel direction may be determined based on the time-series change of the position of the host vehicle calculated up to the previous time.

  The effect | action of the vehicle-mounted measuring apparatus 310 which concerns on 3rd Embodiment is demonstrated.

  In the multipath determination processing routine according to the third embodiment, the information of a plurality of GPS satellites is acquired from the GPS receiver 12, and the phase difference of the received signals between the GPS antennas 12A and 12B is acquired. Then, the direction of each GPS satellite is calculated as the absolute arrival direction of the radio wave from each GPS satellite, and then the relative arrival direction of the radio wave from each GPS satellite based on the traveling direction of the host vehicle. Is calculated.

  And the own vehicle direction estimation process routine mentioned later is performed and the absolute traveling direction of the own vehicle is estimated. Next, based on the estimated relative arrival direction of the radio waves from each GPS satellite and the estimated absolute traveling direction of the host vehicle, the absolute arrival direction of the radio waves from each GPS satellite is estimated. To do. Then, the calculated absolute arrival direction of the radio wave from each GPS satellite and the estimated absolute arrival direction of the radio wave from each GPS satellite are compared for each GPS satellite, and It is determined whether or not the received signal is multipath, and the determination result is output to an external device.

  Next, when there is a received signal from a GPS satellite determined to be multipath, the other GPS satellites acquired except for the pseudorange data of the GPS satellite determined to be multipath. Based on the pseudo distance data, the vehicle position is calculated, map matching is performed, the vehicle position is corrected and output to the external device, and the multipath determination processing routine is terminated. If there is no received signal from a GPS satellite determined to be multipath, the vehicle position is calculated based on the acquired pseudorange data of each GPS satellite and map matching is performed. The vehicle position is corrected and output to the external device, and the multipath determination processing routine is terminated.

  The own vehicle direction estimation processing routine according to the third embodiment will be described with reference to FIG. First, in step 350, the position of the host vehicle calculated previously as described above is acquired. In step 352, the road map data is read from the navigation system, and the position of the host vehicle acquired in step 350 is present. Get direction.

  In step 354, the absolute traveling direction of the host vehicle is estimated based on the road direction acquired in step 352, and the host vehicle direction estimation processing routine is terminated.

  As described above, according to the in-vehicle measurement device according to the third embodiment, the phase difference of the received signals from the GPS satellites received by each of the plurality of GPS antennas is used to The relative arrival direction is estimated, and the absolute arrival direction of the radio wave from each GPS satellite is estimated from the estimated absolute reference direction of the own vehicle. By comparing the absolute arrival direction of the radio wave from each GPS satellite calculated using the known satellite position with each GPS satellite, the received signal from the GPS satellite is multipath with a simple configuration. It can be accurately determined whether or not there is.

  In addition, by estimating the absolute traveling direction of the host vehicle from the direction of the road where the host vehicle is located, the direction of the host vehicle can be determined even if the direction cannot be determined only by information from GPS satellites due to the insufficient number of satellites. Since the azimuth can be estimated, the absolute direction of a robust incoming wave can be estimated, and the multipath determination accuracy can be improved.

  Next, a fourth embodiment will be described. In addition, since the structure of the vehicle-mounted measuring apparatus which concerns on 4th Embodiment becomes a structure similar to 2nd Embodiment, it attaches | subjects the same code | symbol and abbreviate | omits description.

  The fourth embodiment is mainly different from the second embodiment in that the absolute traveling direction of the host vehicle is estimated using the value of the vehicle speed pulse.

  In the in-vehicle measurement device according to the fourth embodiment, the own vehicle direction estimation unit 222 estimates the absolute traveling direction of the own vehicle as follows.

  First, a vehicle speed pulse from a vehicle speed sensor used for display of a navigation system or a speedometer is acquired, and the host vehicle speed is acquired from the value of the vehicle speed pulse.

Similarly to the second embodiment, the relative speed of the host vehicle with respect to each GPS satellite is calculated from the Doppler shift frequency of the received signal from each GPS satellite. Then, based on the relative speed v _{j of} the own vehicle with respect to each GPS satellite j and the speed Vs _j of each GPS satellite j in the direction of the own vehicle calculated in the same manner as in the second embodiment, the direction of each GPS satellite j to the calculated speed Vv _j of the vehicle.

  Next, when the number of GPS satellites that have received radio waves is 2, simultaneous equations represented by the following equation (10) are obtained using Vx, Vy, Vz, and Cb dots as estimated values.

  Further, the following equation (11) is obtained from the acquired own vehicle speed V.

  Here, Vx is approximated to Vz = 0, and Vx and Vy are obtained by solving the simultaneous equations of the above equation (10) using the above equation (11), and the absolute value of the host vehicle is determined by the ratio of Vx and Vy. The typical driving direction.

  Next, the operation of the in-vehicle measurement device according to the fourth embodiment will be described. In addition, about the process similar to 2nd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As in the second embodiment, the computer 214 executes a multipath determination processing routine. Further, as shown in FIG. 12, the vehicle direction estimation processing routine is executed.

  First, in step 400, the value of the vehicle speed pulse is acquired from the vehicle speed sensor, and the vehicle speed is acquired. In step 270, the relative speed of the host vehicle with respect to each GPS satellite is calculated based on the Doppler shift frequency in each GPS satellite acquired in the multipath determination processing routine.

  In the next step 272, the velocity vector of each GPS satellite is calculated. In step 274, the vehicle position previously calculated in the multipath determination processing routine is acquired.

  Then, in step 276, based on the position coordinates of each GPS satellite calculated based on the information of each GPS satellite acquired in the multipath determination processing routine and the vehicle position acquired in step 274, The direction of each GPS satellite is calculated, and in step 278, for each GPS satellite based on the velocity vector of each GPS satellite calculated in step 272 and the direction of each GPS satellite calculated in step 276, The speed of the GPS satellite in the direction of the vehicle is calculated.

  In the next step 280, the vehicle speed in each GPS satellite direction is calculated based on the relative speed for each GPS satellite calculated in step 270 and the speed of each GPS satellite in the vehicle direction calculated in step 278. calculate.

  In step 402, the own vehicle speed in each GPS satellite direction calculated in step 280 and the own vehicle speed obtained in step 400 are used to estimate the speed vector of the own vehicle. Based on the direction of the speed vector, the absolute traveling direction of the host vehicle is estimated, and the host vehicle direction estimation processing routine is terminated.

  As described above, according to the in-vehicle measuring device according to the fourth embodiment, the absolute traveling direction of the host vehicle is estimated using the value of the vehicle speed pulse of the host vehicle, and so on. This makes it possible to estimate the heading of the host vehicle even when the heading of the host vehicle cannot be determined by only the information from the GPS satellites, thus making it possible to estimate the absolute direction of the robust incoming wave and improving the multipath determination accuracy. To do.

  In the above embodiment, the case where the number of GPS satellites that have received radio waves is two has been described as an example. However, the present invention is not limited to this, and the number of GPS satellites that have received radio waves is three or more. There may be. In this case, the absolute traveling direction of the host vehicle is estimated using each pair of two GPS satellites, and the absolute traveling direction of the host vehicle is estimated by combining these estimation results. do it.

  Next, a fifth embodiment will be described. In addition, since the structure of the vehicle-mounted measuring apparatus which concerns on 5th Embodiment becomes a structure similar to 2nd Embodiment, it attaches | subjects the same code | symbol and abbreviate | omits description.

  The fifth embodiment is mainly different from the second embodiment in that the absolute traveling direction of the host vehicle is estimated using the value of the vehicle speed pulse and the drift of the clock bias. Yes.

  In the in-vehicle measurement device according to the fifth embodiment, the vehicle position calculation unit 28 determines that the received signal is multipath among the pseudorange data obtained for all GPS satellites that have received radio waves. By excluding the GPS satellite pseudorange data and solving the simultaneous equations of the above equation (4) obtained using the remaining GPS satellite pseudorange data, the position (x, y, z) of the host vehicle and the clock bias are obtained. The distance error s is calculated, and the clock bias is calculated from the distance error s and stored in the memory.

  The own vehicle direction estimation unit 222 estimates the absolute traveling direction of the own vehicle as follows. A case where the number of GPS satellites that have received radio waves is 1 will be described.

  First, the time series data of the clock bias calculated in the past as described above is acquired from the memory, and the clock bias drift (the drift component of the clock bias that changes with time) is predicted from the time series data of the clock bias.

  Further, the vehicle speed pulse from the vehicle speed sensor is acquired, and the host vehicle speed is acquired from the value of the vehicle speed pulse.

  Similarly to the second embodiment, the relative speed of the host vehicle with respect to the GPS satellite is calculated from the Doppler shift frequency of the received signal from the GPS satellite.

Also, the vehicle in the direction of the GPS satellite j based on the relative speed v _{j of} the vehicle with respect to the GPS satellite j and the velocity Vs _j of the GPS satellite j in the direction of the vehicle calculated in the same manner as in the second embodiment. to calculate the speed Vv _j.

  An equation represented by the following expression (12) is obtained using the dots of Vx, Vy, Vz, and Cb as estimated values.

  Here, while approximating Vz = 0, the equation of the above equation (12) is solved by using the above equation (11) obtained by using the acquired own vehicle speed v and the dot of the calculated clock bias drift Cb. Thus, Vx and Vy are obtained, and the absolute traveling direction of the host vehicle is estimated from the ratio of Vx and Vy.

  Next, the operation of the in-vehicle measurement device according to the fifth embodiment will be described. In addition, about the process similar to 2nd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As in the second embodiment, the computer 214 executes a multipath determination processing routine. Further, as shown in FIG. 13, a host vehicle direction estimation processing routine is executed. In the following, a case where the number of GPS satellites that have received radio waves is 1 will be described as an example.

  First, in step 500, the clock bias time-series data obtained in the previous position calculation is acquired from the memory, and in step 502, the clock bias drift is calculated from the clock bias time-series data acquired in step 500 above. To do.

  In step 400, the value of the vehicle speed pulse is acquired from the vehicle speed sensor, and the vehicle speed is acquired. In step 270, the relative speed of the host vehicle with respect to the GPS satellite is calculated based on the Doppler shift frequency in the GPS satellite acquired in the multipath determination processing routine.

  In the next step 272, the velocity vector of the GPS satellite is calculated, and in step 274, the vehicle position previously calculated in the multipath determination processing routine is acquired.

  In step 276, the GPS satellite is calculated based on the position coordinates of the GPS satellite calculated based on the GPS satellite information acquired in the multipath determination processing routine and the own vehicle position acquired in step 274. In step 278, based on the GPS satellite velocity vector calculated in step 272 and the GPS satellite direction calculated in step 276, the GPS satellite in the direction of the vehicle is calculated. Calculate the speed of.

  In the next step 280, the vehicle speed in the GPS satellite direction is calculated based on the relative speed with respect to the GPS satellite calculated in step 270 and the speed of the GPS satellite in the vehicle direction calculated in step 278.

  In step 504, the vehicle speed in the GPS satellite direction calculated in step 280, the vehicle speed obtained in step 400, and the clock bias drift value calculated in step 502 are used. The speed vector of the vehicle is estimated, the absolute traveling direction of the host vehicle is estimated based on the estimated direction of the speed vector of the host vehicle, and the host vehicle direction estimation processing routine is terminated.

  Thus, by estimating the absolute traveling direction of the host vehicle using the clock bias drift calculated from the clock drift obtained at the time of position calculation and the value of the vehicle speed pulse of the host vehicle, the number of satellites is estimated. Even when the direction of the subject vehicle cannot be determined by GPS satellite information alone due to lack of information, the orientation of the subject vehicle can be estimated, so the absolute direction of the incoming wave can be estimated robustly and the multipath determination accuracy is improved. To do.

  In the above embodiment, the case where the clock bias drift is calculated when estimating the traveling direction of the host vehicle has been described as an example. However, the present invention is not limited to this. Since the value of the clock bias drift is basically considered to be a constant value for a short time and does not vary greatly, the clock bias drift value calculated in the past may be used for about several minutes.

  In the above embodiment, the case where the number of GPS satellites that have received radio waves is 1 has been described as an example. However, the present invention is not limited to this, and the number of GPS satellites that have received radio waves is 2 or more. There may be. In this case, the absolute traveling direction of the host vehicle is estimated using the information of each GPS satellite that has received the radio wave, and the absolute traveling direction of the host vehicle is estimated by combining these estimation results. You just have to do it.

  In the second to fifth embodiments, the absolute arrival of radio waves is determined from the estimated absolute traveling direction of the host vehicle and the estimated relative arrival direction of the radio waves. Although the case where multipath is determined by estimating the direction and comparing the absolute arrival directions is described as an example, the present invention is not limited to this. By calculating the relative arrival direction of the radio wave from the estimated absolute traveling direction of the vehicle and the calculated absolute arrival direction of the radio wave, and comparing the relative arrival directions, The path may be determined.

  Moreover, you may make it estimate the absolute traveling direction of the own vehicle combining the estimation method of the traveling direction of the own vehicle in 2nd Embodiment-5th Embodiment. Moreover, you may further combine the method of estimating the absolute running direction of the own vehicle from the phase difference and positioning difference of a received signal.

  Next, a sixth embodiment will be described. In addition, about the part which becomes the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the sixth embodiment, the received signal from the GPS satellite is based on the fact that there are three GPS antennas and whether there is a shield in the relative arrival direction of the estimated radio wave. It is mainly different from the first embodiment in that it is determined whether or not it is multipath and a plurality of types of multipath determination methods are used.

  As shown in FIG. 14, the GPS receiver 612 of the in-vehicle measuring apparatus 610 according to the sixth embodiment includes three GPS antennas 612A, 612B, and 612C that receive radio waves from GPS satellites. The GPS antennas 612A, 612B, and 612C receive radio waves from GPS satellites. The distances between the GPS antennas 612A, 612B, and 612C are known.

  The computer 614 acquires GPS satellite information for all GPS satellites that have received radio waves from the GPS receiver 612, and calculates and acquires the phase difference of each received signal between the GPS antennas 612A, 612B, and 612C. Based on the phase differences between the GPS antennas 612A, 612B, and 612C of the GPS satellites acquired, the GPS wave information acquisition unit 620, the incoming wave absolute direction calculation unit 22, and the acquired GPS satellites. An arrival wave relative direction estimation unit 624 that estimates an arrival direction (an elevation angle with respect to the horizontal plane and an azimuth angle on the horizontal plane), an estimated relative arrival direction of the radio wave from each GPS satellite, and an absolute radio wave from each GPS satellite Multipath determination unit 6 that compares the total arrival directions and determines whether or not the received signal from each GPS satellite is a multipath. 6 and based on the road map data obtained from the vehicle position calculation unit 28 and the navigation system, it is determined whether or not there is an obstruction in the relative arrival direction of the radio wave from each GPS satellite estimated. And a second multipath determination unit 640 that determines whether or not the received signal from each GPS satellite is a multipath.

  The GPS information acquisition unit 620 acquires GPS satellite information for all GPS satellites that have received radio waves from the GPS reception unit 612, and GPS antennas 612A, 612B, and 613B for all GPS satellites that have received radio waves. Based on each received signal, the phase difference of each received signal between the GPS antennas 612A, 612B, 612C is calculated.

  The incoming wave relative direction estimation unit 624 is based on the phase difference of the received signals between the GPS antennas 612A, 612B, and 612C calculated for each GPS satellite and the distance L between the GPS antennas 612A, 612B, and 612C. Thus, the relative arrival directions of radio waves from each GPS satellite (the elevation angle with respect to the horizontal plane and the azimuth angle on the horizontal plane) with respect to the traveling direction of the host vehicle are estimated.

  The multipath determination unit 626 includes a relative arrival direction of radio waves from each GPS satellite estimated by the arrival wave relative direction estimation unit 624 (an elevation angle with respect to the horizontal plane and an azimuth angle on the horizontal plane), and an arrival wave absolute direction calculation unit 22. Comparing the absolute arrival directions (elevation angle with respect to the horizontal plane and the azimuth angle with respect to the north direction) of the radio waves from each GPS satellite calculated as described above, the satellites that do not match both the elevation angle and the azimuth angle as the arrival direction are compared. Multipath is determined by estimation.

  The second multipath determination unit 640 acquires road map data including building information along the road from the navigation system, and from the road map data, around the own vehicle position calculated by the own vehicle position calculation unit 28 (the own vehicle Acquire building information (information including the position and height of the building) along the road where the position exists. Based on the acquired building information, the second multipath determination unit 640 determines the relative arrival direction of radio waves from each GPS satellite estimated by the arrival wave relative direction estimation unit 624 (the elevation angle with respect to the horizontal plane and the azimuth angle on the horizontal plane). ), It is determined whether there is a building that becomes a shielding object, and multipath is determined by estimating a GPS satellite in which the shielding object exists in the relative arrival direction of radio waves.

  The own vehicle position calculation unit 28 determines that the received signal is multipath by the multipath determination unit 626 or the second multipath determination unit 640 out of the pseudo distance data obtained for all GPS satellites that have received radio waves. The position (x, y, z) of the host vehicle is calculated by excluding the pseudorange data of the GPS satellites and solving the simultaneous equation (4) obtained using the pseudorange data of the remaining GPS satellites. To do.

  Next, the operation of the in-vehicle measurement device 610 according to the sixth embodiment will be described.

  When the GPS receiving unit 612 receives radio waves from a plurality of GPS satellites, the computer 614 executes a multipath determination processing routine as follows.

  First, the information of a plurality of GPS satellites is acquired from the GPS receiving unit 612, and the phase difference of each received signal between the GPS antennas 612A, 612B, 612C of the plurality of GPS satellites is acquired and acquired.

  Then, based on the position coordinates of each GPS satellite included in the acquired information of each GPS satellite and the calculated own vehicle position, the direction of each GPS satellite is determined as the absolute arrival direction of the radio wave from each GPS satellite. Calculate as Next, based on the phase difference of the received signal from each GPS satellite for each of the acquired GPS antennas 612A, 612B, 612C, the relative radio wave from each GPS satellite based on the traveling direction of the host vehicle The direction of arrival (elevation angle relative to the horizontal plane and azimuth angle on the horizontal plane) is estimated.

  Then, the calculated absolute arrival direction of the radio wave from each GPS satellite is compared with the estimated relative arrival direction of the radio wave from each GPS satellite as a whole, and the elevation angle and azimuth angle in the arrival direction are Based on whether or not they match, it is determined whether or not the received signal from each GPS satellite is multipath, and the determination result is output to an external device.

  Next, when there is a received signal from a GPS satellite determined to be multipath in the above determination processing or a second multipath determination processing routine described later, the GPS in which the reception signal is determined to be multipath. Except for the satellite pseudorange data, based on the obtained pseudorange data of other GPS satellites, the vehicle position is calculated and output to the external device, and the multipath determination processing routine is terminated. On the other hand, when there is no received signal from a GPS satellite determined to be multipath, based on the acquired pseudorange data of each GPS satellite, the vehicle position is calculated and output to an external device, The multipath determination processing routine is terminated.

  Further, in the computer 614, a second multipath determination processing routine shown in FIG. 15 is executed in parallel with the above-described multipath determination processing routine.

  First, in step 650, the relative arrival directions (elevation angle and azimuth angle) of radio waves from each GPS satellite estimated by the multipath determination processing routine are acquired. In step 652, road map data is acquired from the navigation system, and peripheral building information is acquired from the road map data for the position of the host vehicle most recently calculated by the multipath determination processing routine.

  In the next step 654, based on the surrounding building information acquired in step 652, the GPS satellites become shields in the relative arrival direction (elevation angle and azimuth angle) of the radio wave acquired in step 650. It is determined whether a building exists, it is determined whether the received signal from each GPS satellite is multipath, the determination result is output to an external device, and the second multipath determination processing routine is terminated.

  As described above, according to the in-vehicle measurement device according to the sixth embodiment, the estimated direction of arrival of radio waves is compared to determine multipath, and the shielding object is located in the estimated direction of arrival of radio waves. By determining whether or not it exists, determining the multipath, and combining the determination results, it is possible to more accurately determine whether or not the received signal from the GPS satellite is a multipath.

  Next, a seventh embodiment will be described. In addition, about the part which becomes the structure similar to 1st Embodiment and 6th Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the seventh embodiment, the sixth embodiment is that it is determined whether or not there is a shield in the relative arrival direction of the estimated radio wave using an image obtained by imaging the periphery. And mainly different.

  As shown in FIG. 16, the on-vehicle measuring device 710 according to the seventh embodiment includes an imaging device 712 that is installed so as to image the periphery (particularly the side) of the host vehicle, and the imaging device 712 is a computer. 714.

  The computer 714 of the in-vehicle measuring device 710 includes a GPS information acquisition unit 620, an incoming wave absolute direction calculation unit 22, an incoming wave relative direction estimation unit 624, a multipath determination unit 626, an own vehicle position calculation unit 28, and an imaging. Based on the detection result of the shielding object detection unit 738 that detects the shielding object from the peripheral image captured by the device 712, and the detection result of the shielding object detection unit 738, in the relative arrival direction of the radio wave from each GPS satellite, A second multipath determination unit 740 that determines whether or not a received signal from each GPS satellite is a multipath by determining whether or not a shield is present.

  The shielding object detection unit 738 performs image recognition processing on a peripheral image captured by the imaging device 712 to detect a shielding object such as a building, and also detects the position and height of the shielding object present in the vicinity. To do.

  The second multipath determination unit 740 acquires the detection result by the shielding object detection unit 738. The second multipath determination unit 740 uses the relative position of the radio wave from each GPS satellite estimated by the arrival wave relative direction estimation unit 624 based on the position and height of the shielding object present in the periphery represented by the acquired detection result. Multipath is determined by determining whether there is a building that becomes a shielding object in a certain direction of arrival (elevation angle and azimuth angle), and estimating a GPS satellite that has a shielding object in the relative direction of arrival of radio waves. judge.

  Next, the operation of the in-vehicle measurement device 710 according to the seventh embodiment will be described.

  When the GPS receiver 612 is receiving radio waves from a plurality of GPS satellites, the computer 714 executes a multipath determination processing routine in the same manner as in the sixth embodiment.

  In addition, when images around the host vehicle are continuously captured by the imaging device 712, the computer 714 performs the second multipath determination processing routine shown in FIG. 17 in parallel with the multipath determination processing routine described above. Is executed. Note that the same processes as those of the sixth embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  First, in step 750, a peripheral image is acquired from the imaging device 712, and in step 752, a building that becomes a shield is detected from the peripheral image acquired in step 750, and the position where the building exists and the height of the building are determined. To detect.

  In step 650, the relative arrival directions (elevation angle and azimuth angle) of radio waves from each GPS satellite estimated by the multipath determination processing routine are acquired. In step 756, the relative arrival direction (elevation angle and azimuth angle) of the radio wave acquired in step 650 is obtained for each GPS satellite based on the position and height of the building existing in the vicinity detected in step 752. In addition, it is determined whether there is a building that becomes a shielding object, it is determined whether the received signal from each GPS satellite is multipath, the determination result is output to an external device, and a second multipath determination process is performed. End the routine.

  In this way, the estimated arrival directions are compared to determine the multipath, and whether or not there is an obstacle in the direction of arrival of the radio wave, and the multipath is determined, thereby determining the multipath. Whether or not the received signal is multipath can be determined with higher accuracy.

  In the sixth embodiment and the seventh embodiment described above, multipath is determined by determining whether there is an obstruction in the direction of arrival of radio waves based on road map data and surrounding images. Although the case has been described as an example, the present invention is not limited to this, and multipath may be determined based only on the estimated arrival direction of radio waves. The received signal from the GPS satellite is multipath depending on whether or not the estimated relative arrival direction of the radio wave from the GPS satellite is a predetermined direction in which there is a high possibility that a shielding object exists. It may be determined whether or not. For example, if the relative arrival direction of radio waves from a GPS satellite is a direction orthogonal to the traveling direction, a direction along a road, or the elevation angle of the arrival direction is low, there is a possibility of multipath. May be determined to be high.

  Next, an eighth embodiment will be described. In addition, about the part which becomes the same structure as 1st Embodiment and 2nd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The eighth embodiment is mainly different from the first embodiment in that it is determined whether or not a received signal from a GPS satellite is a multipath using a plurality of types of multipath determination methods. Is different.

  As shown in FIG. 18, the GPS receiver 12 of the in-vehicle measuring device 810 according to the eighth embodiment receives radio waves from a plurality of GPS satellites, and receives received signals from all the received GPS satellites. As the GPS satellite information, the satellite number, carrier phase, code pseudorange, Doppler shift frequency, signal intensity, and orbit information of the GPS satellite are acquired and output to the computer 814. GPS satellite information is acquired for each of the antennas 12A and 12B and output to the computer 814.

  The computer 814 obtains GPS satellite information for each antenna for all GPS satellites that have received radio waves from the GPS receiver 12 and obtains the phase difference of the received signals between the GPS antennas 12A and 12B. Unit 820, arrival wave absolute direction calculation unit 22, arrival wave relative direction estimation unit 24, multipath determination unit 26, own vehicle position calculation unit 28, and GPS information acquisition unit 220. Based on the GPS pseudorange data and the phase difference between the received signals, the second multipath determining unit 824 that determines whether or not the received signal from each GPS satellite is a multipath, and the GPS information acquiring unit 220 Based on the Doppler shift frequency of each GPS satellite, a third marker for determining whether or not the received signal from each GPS satellite is multipath. And a-path determination unit 826. The second multipath determination unit 824 is an example of a third determination unit, and the third multipath determination unit 826 is an example of a fourth determination unit.

  The GPS information acquisition unit 820 acquires GPS satellite information for each GPS antenna 12A and 12B for all GPS satellites that have received radio waves from the GPS reception unit 12, and calculates the phase difference between the GPS antennas 12A and 12B. To do. Further, the position of the GPS satellite and the transmission time at which the GPS satellite transmits radio waves are estimated and acquired based on the GPS satellite information acquired from the received signal.

  For each GPS satellite, the second multipath determination unit 824 determines the difference between the GPS pseudorange data of the GPS satellite between the GPS antennas 12A and 12B and the phase difference between the received signals of the GPS satellites between the GPS antennas 12A and 12B. If these differences are equal to or greater than the threshold, it is determined that the received signal from the GPS satellite is multipath. If these differences are less than the threshold, the received signal from the GPS satellite is not multipath. Judge that there is no.

  For example, as shown in FIG. 19, when the path of the radio wave received between the GPS antennas 12A and 12B is greatly different, the difference in the GPS pseudorange data obtained between the GPS antennas 12A and 12B becomes large. However, exceeding the maximum value (2π) of the phase difference of the received signal reduces the phase difference of the received signal. Therefore, the difference between the difference in the GPS pseudorange data and the phase difference of the received signal becomes large, and it is determined that the received signal from the GPS satellite is multipath. As for the threshold used in the above determination, the difference between the GPS pseudorange data between the antennas and the received signal between the antennas when the multipath received signal is received only by one of the GPS antennas experimentally or statistically. What is necessary is just to obtain a difference from the phase difference in advance, and to set a threshold based on the obtained difference.

  For each GPS satellite, the third multipath determination unit 826 determines that the received signal from the GPS satellite is multipath if the difference in Doppler shift frequency between the GPS antennas 12A and 12B is equal to or greater than a threshold value. If this difference is less than the threshold, it is determined that the received signal from the GPS satellite is not multipath. Normally, a difference in Doppler shift frequency between the GPS antennas 12A and 12B occurs in a range corresponding to vehicle motion (yaw rate) that can occur in the host vehicle. For example, as shown in FIG. When the path of the radio wave received at 1 is greatly different, the difference in the Doppler shift frequency obtained between the GPS antennas 12A and 12B is increased, and the received signal from the GPS satellite is determined to be multipath.

  Note that the threshold value used in the above determination is obtained by experimentally or statistically obtaining in advance a difference in Doppler shift frequency between antennas when a multipath received signal is received by only one GPS antenna. A threshold may be set based on the difference.

  Next, the effect | action of the vehicle-mounted measuring apparatus 810 which concerns on 8th Embodiment is demonstrated.

  When the GPS receiver 12 receives radio waves from a plurality of GPS satellites, the computer 814 executes a multipath determination processing routine as follows.

  First, information on a plurality of GPS satellites is acquired from the GPS receiving unit 12, and a phase difference between reception signals between the GPS antennas 12A and 12B of the plurality of GPS satellites is acquired.

  Then, based on the position coordinates of each GPS satellite calculated based on the acquired information of each GPS satellite and the calculated position of the own vehicle, the direction of each GPS satellite is determined based on the absolute radio wave from each GPS satellite. It is calculated as the correct direction of arrival. Next, based on the phase difference of the received signal from each GPS satellite between the acquired GPS antennas 12A and 12B, the relative arrival direction of the radio wave from each GPS satellite is estimated based on the antenna installation direction.

  Then, the absolute arrival direction of the radio wave from each GPS satellite and the estimated relative arrival direction of the radio wave from each GPS satellite are compared as a whole, and a received signal from each GPS satellite is obtained. It is determined whether the path is multipath, and the determination result is output to an external device.

  Next, if there is a received signal from a GPS satellite determined to be multipath in the above determination, the second multipath determination processing routine described later, or the third multipath determination processing routine described later, a reception is performed. Based on the pseudorange data of other GPS satellites acquired, except for the GPS satellite pseudorange data for which the signal is determined to be multipath, the vehicle position is calculated and output to an external device, and multipath determination is made. The processing routine ends. On the other hand, when there is no received signal from a GPS satellite determined to be multipath, based on the acquired pseudorange data of each GPS satellite, the vehicle position is calculated and output to an external device, The multipath determination processing routine is terminated.

  Further, in the computer 814, a second multipath determination processing routine shown in FIG. 20 is executed in parallel with the above-described multipath determination processing routine.

  First, in step 850, for each GPS satellite, the GPS pseudorange data for each GPS antenna 12A, 12B is calculated based on the output from the GPS receiver 12, and the GPS pseudorange data between the GPS antennas 12A, 12B is calculated. Calculate and obtain the difference.

  In step 852, for each GPS satellite, the difference between the GPS pseudorange data between the GPS antennas 12A and 12B acquired in step 850 and the reception between the GPS antennas 12A and 12B acquired in the multipath determination processing routine. The difference from the phase difference of the signal is calculated.

  In the next step 854, it is determined whether or not the received signal from each GPS satellite is multipath by determining whether or not the difference calculated in step 852 is greater than or equal to a threshold value for each GPS satellite. Determine, output the determination result to the external device, and terminate the second multipath determination processing routine.

  Further, in the computer 814, a third multipath determination processing routine shown in FIG. 21 is executed in parallel with the multipath determination processing routine and the second multipath determination processing routine.

  First, in step 860, for each GPS satellite, the Doppler shift frequency for each of the GPS antennas 12A and 12B is acquired based on the output from the GPS receiver 12, and the difference in Doppler shift frequency between the GPS antennas 12A and 12B is obtained. Calculate and get.

  In step 862, for each GPS satellite, it is determined whether the difference in Doppler shift frequency calculated in step 860 is greater than or equal to a threshold value, so that the received signal from each GPS satellite is multipath. Whether or not, the determination result is output to the external device, and the third multipath determination processing routine is terminated.

  As described above, according to the in-vehicle measurement device according to the eighth embodiment, whether or not the received signal from each GPS satellite is a multipath by combining a plurality of types of multipath determination methods. It can be determined with high accuracy.

  In the above embodiment, the case where multipath is determined using the difference in pseudo distance between antennas has been described as an example. However, the present invention is not limited to this, and the difference in GPS radio wave propagation time between antennas is described. And the difference between the received signal and the phase difference of the received signal may be used to determine whether the received signal is multipath or not. In this case, the GPS radio wave propagation time may be calculated based on the time when the GPS satellite transmits the radio wave and the time when the vehicle receives the radio wave.

  In the sixth to eighth embodiments, the multipath determination method for determining the multipath by comparing the arrival directions as a whole and the other multipath determination method are combined. Although described as an example, the present invention is not limited to this, and the multipath determination methods in the second to fifth embodiments are the same as those in the sixth to eighth embodiments. The determination methods of the second multipath determination unit or the third multipath determination unit may be combined.

  Also, the determination method by the second multipath determination unit 640 in the sixth embodiment, the determination method by the second multipath determination unit 740 in the seventh embodiment, and the second multipath determination in the eighth embodiment An arbitrary combination of the determination method by the unit 824 and the determination method by the third multipath determination unit 826 is combined with the multipath determination method in the first to fifth embodiments, It may be determined whether the received signal is multipath.

  Moreover, although the case where the received signal from the GPS satellite determined to be multipath by any one of the determination methods is finally determined to be multipath has been described as an example, it is not limited to this. A received signal from a GPS satellite determined to be multipath by all the determination methods may be finally determined to be multipath, and it is determined to be multipath by at least two determination methods. The received signal from the GPS satellite may be finally determined as multipath.

  In addition, in the first to eighth embodiments described above, a multipath determination method using a conventionally known pseudorange residual or the like is combined, so that a received signal from each GPS satellite is a multipath. You may make it determine whether it exists. In this case, the procedure and combination may be arbitrary.

  Moreover, you may make it calculate the position of the own vehicle using GPS radio wave propagation time instead of pseudorange data.

  Moreover, although the case where the value of position calculation using pseudorange data was used as an example of the position of the host vehicle used when calculating the direction of the GPS satellite was described, it is not limited to this. When obtaining the direction of the GPS satellite, it is only necessary to know the rough position of the own vehicle. Therefore, the position of the own vehicle obtained from map data or the like may be used.

  In addition, the case where the position of the host vehicle is calculated using the multipath determination result has been described as an example, but the present invention is not limited to this. When estimating, the reflection point may be predicted using the determination result of multipath. Further, the speed of the host vehicle may be calculated and output to an external device. In this case, the speed of the host vehicle can be calculated using the multipath determination result.

10, 210, 310, 610, 710, 810 On-vehicle measuring device 12A, 12B, 612A, 612B, 612C GPS antenna 12, 612 GPS receiver 14, 214, 314, 614, 714, 814 Computer 20, 220, 620, 820 GPS information acquisition unit 22 Arrival wave absolute direction calculation unit 24, 624 Arrival wave relative direction estimation unit 26, 226, 626 Multipath determination unit 28, 328 Own vehicle position calculation unit 222 Own vehicle direction estimation unit 224 Arrival wave absolute direction estimation unit 322 Self-vehicle direction estimation unit 640, 740, 824 Second multipath determination unit 712 Imaging device 738 Shielding object detection unit 826 Third multipath determination unit

Claims (19)

GPS receiving means having a plurality of antennas for receiving radio waves from GPS satellites;
Acquisition means for acquiring the information on the GPS satellites received by the GPS receiving means and the phase difference of the received signals from the GPS satellites received by each of the plurality of antennas for all of the GPS satellites that have received the radio waves; ,
For each GPS satellite, relative direction estimation means for estimating the relative arrival directions of radio waves from the GPS satellite based on the phase difference of the received signals from the GPS satellite acquired by the acquisition means;
For each GPS satellite, based on the information of the GPS satellite acquired by the acquisition unit, an absolute direction calculation unit that calculates an absolute arrival direction of radio waves from the GPS satellite;
The relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation unit and the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculation unit are compared as a whole. A determination means for determining whether the received signal from each GPS satellite is multipath,
Multipath determination device including GPS receiving means having a plurality of antennas for receiving radio waves from GPS satellites;
Acquisition means for acquiring the information on the GPS satellites received by the GPS receiving means and the phase difference of the received signals from the GPS satellites received by each of the plurality of antennas for all of the GPS satellites that have received the radio waves; ,
For each GPS satellite, relative direction estimation means for estimating the relative arrival directions of radio waves from the GPS satellite based on the phase difference of the received signals from the GPS satellite acquired by the acquisition means;
For each GPS satellite, based on the position information of the GPS satellite acquired by the acquisition means, absolute direction calculation means for calculating the absolute arrival direction of the radio wave from the GPS satellite,
Own vehicle direction estimating means for estimating an absolute reference direction of the own vehicle;
From the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimating means and the absolute reference direction of the own vehicle estimated by the own vehicle direction estimating means, By comparing the absolute arrival direction of the radio wave with the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculating unit, the received signal from each GPS satellite is obtained. Determining means for respectively determining whether or not multipath,
Multipath determination device including GPS receiving means having a plurality of antennas for receiving radio waves from GPS satellites;
Acquisition means for acquiring the position information of the GPS satellites received by the GPS receiving means and the phase difference of the received signals from the GPS satellites received by each of the plurality of antennas for all the GPS satellites that have received the radio waves. When,
For each GPS satellite, relative direction estimation means for estimating the relative arrival directions of radio waves from the GPS satellite based on the phase difference of the received signals from the GPS satellite acquired by the acquisition means;
For each GPS satellite, based on the position information of the GPS satellite acquired by the acquisition means, absolute direction calculation means for calculating the absolute arrival direction of the radio wave from the GPS satellite,
Own vehicle direction estimating means for estimating an absolute reference direction of the own vehicle;
The relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation unit, the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculation unit, and the own vehicle direction By comparing the relative arrival direction of the radio wave from each GPS satellite, which is obtained from the absolute reference direction of the host vehicle estimated by the estimation means, for each GPS satellite, the received signal from each GPS satellite is obtained. Determining means for respectively determining whether or not multipath,
Multipath determination device including The acquisition means acquires the position information of the GPS satellite, the phase difference of the received signal from the GPS satellite, and the Doppler frequency of the received signal from the GPS satellite for all the GPS satellites that have received the radio waves,
The own vehicle direction estimating means includes a relative speed calculating means for calculating a relative speed of the own vehicle with respect to each GPS satellite based on each of the Doppler frequencies acquired by the acquiring means, and is calculated by the relative speed calculating means. 4. The multipath determination device according to claim 2, wherein an absolute reference direction of the host vehicle is estimated using the relative speed that has been set.   The own vehicle direction estimation means calculates the speed of each GPS satellite from the acquired GPS satellite information, and calculates the relative speed for each GPS satellite calculated by the relative speed calculation means and each calculated GPS Based on the speed of the satellite, the vehicle speed calculation means for calculating the speed of the vehicle in each GPS satellite direction, and the speed vector of the host vehicle is estimated based on the calculated speed of the vehicle in each GPS satellite direction The multipath determination device according to claim 4, further comprising: a speed vector estimation unit configured to estimate an absolute reference direction of the host vehicle based on the speed vector of the host vehicle estimated by the speed vector estimation unit. It further includes position calculation means for calculating the position of the host vehicle,
The own vehicle direction estimating means acquires the direction of the road where the position of the own vehicle calculated by the position calculating means exists from road map information stored in advance, and based on the acquired road direction, The multipath determination device according to claim 2, wherein the absolute reference direction is estimated.   The own vehicle direction estimation means calculates the speed of each GPS satellite from the acquired GPS satellite information, and calculates the relative speed for each GPS satellite calculated by the relative speed calculation means and each calculated GPS Based on the speed of the satellite, own vehicle speed calculating means for calculating the speed of the own vehicle in each GPS satellite direction, vehicle speed acquiring means for acquiring the vehicle speed of the own vehicle, and each GPS calculated for at least two GPS satellites The vehicle further comprises speed vector estimation means for estimating the speed vector of the host vehicle based on the speed of the host vehicle in the satellite direction and the acquired vehicle speed of the host vehicle, and the host vehicle estimated by the speed vector estimation unit The multipath determination device according to claim 4, wherein an absolute reference direction of the host vehicle is estimated based on the speed vector.   The own vehicle direction estimation means calculates the speed of each GPS satellite from the acquired GPS satellite information, and calculates the relative speed for each GPS satellite calculated by the relative speed calculation means and each calculated GPS Based on the speed of the satellite, the own vehicle speed calculating means for calculating the speed of the own vehicle in each GPS satellite direction, the vehicle speed acquiring means for acquiring the vehicle speed of the own vehicle, and the rate of change with time of the clock bias are shown. Clock bias drift calculating means for calculating clock bias drift, the speed of the host vehicle in the direction of the GPS satellite calculated for at least one GPS satellite, the obtained vehicle speed of the host vehicle, and the calculated clock bias drift Speed vector estimation means for estimating the speed vector of the host vehicle based on the speed vector estimation means, Based on the velocity vector of the vehicle which is more estimated multipath determination apparatus according to claim 4, wherein estimating the absolute reference direction of the vehicle.   Whether the received signal from each GPS satellite is multipath based on whether there is a shield in the relative arrival direction of the radio waves from each GPS satellite estimated by the relative direction estimating means The multipath determination device according to any one of claims 1 to 8, further comprising a second determination unit that determines whether or not. Imaging means for imaging the surroundings of the host vehicle;
A shielding object detecting means for detecting the shielding object from the image captured by the imaging means,
The second determination unit determines whether there is a shield in the relative arrival direction of the radio waves from the estimated GPS satellites based on a detection result of the shield detection unit. The multipath determination device according to 9. It further includes position calculation means for calculating the position of the host vehicle,
The shielding object determination means obtains presence / absence of an obstacle present around the position of the host vehicle calculated by the position calculation means from road map information stored in advance, and obtains from each estimated GPS satellite. The multipath determination device according to claim 9, wherein it is determined whether or not a shielding object exists in a relative arrival direction of radio waves.   Each GPS satellite is based on whether or not the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation means is a predetermined direction in which there is a possibility that a shielding object exists. The multipath determination device according to any one of claims 1 to 8, further comprising second determination means for determining whether or not a received signal from the multipath is multipath. The acquisition means further determines the GPS radio wave propagation time from when the radio wave is transmitted from the GPS satellite until it reaches the host vehicle or the pseudo distance to the GPS satellite for all the GPS satellites that have received the radio wave. Get every
For each GPS satellite, by comparing the difference in the GPS radio wave propagation time between the antennas or the difference in the pseudo distance with the phase difference of the received signal from the GPS satellite, the received signal from each GPS satellite is The multipath determination device according to any one of claims 1 to 12, further comprising third determination means for determining whether or not each path is a path. The acquisition means further acquires the Doppler frequency of the reception signal from the GPS satellite for each of the antennas for all the GPS satellites that have received the radio waves,
14. The fourth determination unit according to claim 1, further comprising fourth determination means for determining whether or not a received signal from each GPS satellite is multipath based on a difference in Doppler frequency between the antennas in each GPS satellite. The multipath determination device according to any one of the preceding claims. The GPS receiving means includes three or more antennas,
The relative direction estimation means, for each GPS satellite, based on the phase difference between the antennas of the received signal from the GPS satellite acquired by the acquisition means, the elevation angle and azimuth angle of the radio wave from the GPS satellite Estimate the relative directions of arrival represented by
The absolute direction calculation means calculates, for each GPS satellite, an absolute arrival direction represented by an elevation angle and an azimuth angle of the radio wave from the GPS satellite based on the information of the GPS satellite acquired by the acquisition means. The multipath determination device according to any one of claims 1 to 14. The acquisition means further acquires the GPS radio wave propagation time from when the radio wave is transmitted from the GPS satellite to reach the host vehicle or the pseudo distance to the GPS satellite for all the GPS satellites that have received the radio wave,
The position calculation means which calculates the position of the own vehicle further based on the GPS radio wave propagation time or the pseudo distance of each GPS satellite other than the GPS satellite determined that the received signal is multipath. 16. The multipath determination device according to any one of items 15. Computer
The information of the GPS satellite received by the GPS receiving means having a plurality of antennas for receiving radio waves from the GPS satellites, and the phase difference of the received signals from the GPS satellites received by each of the plurality of antennas, Acquisition means for acquiring all of the GPS satellites that received
For each GPS satellite, relative direction estimation means for estimating the relative arrival directions of radio waves from the GPS satellite based on the phase difference of the received signals from the GPS satellite acquired by the acquisition means,
For each GPS satellite, the absolute direction calculation means for calculating the absolute arrival direction of the radio wave from the GPS satellite based on the information of the GPS satellite acquired by the acquisition means, and the relative direction estimation means By comparing the relative arrival direction of the radio waves from each GPS satellite and the absolute arrival direction of the radio waves from each GPS satellite calculated by the absolute direction calculation means as a whole, A program for functioning as a determination means for determining whether a received signal is multipath or not. Computer
The information of the GPS satellite received by the GPS receiving means having a plurality of antennas for receiving radio waves from the GPS satellites, and the phase difference of the received signals from the GPS satellites received by each of the plurality of antennas, Acquisition means for acquiring all of the GPS satellites that received
For each GPS satellite, relative direction estimation means for estimating the relative arrival directions of radio waves from the GPS satellite based on the phase difference of the received signals from the GPS satellite acquired by the acquisition means,
For each GPS satellite, based on the position information of the GPS satellite acquired by the acquisition unit, an absolute direction calculation unit that calculates an absolute arrival direction of radio waves from the GPS satellite,
A vehicle direction estimation unit that estimates an absolute reference direction of the vehicle, a relative arrival direction of radio waves from each GPS satellite estimated by the relative direction estimation unit, and the vehicle direction estimation unit The absolute arrival direction of the radio wave from each GPS satellite obtained from the absolute reference direction of the own vehicle and the absolute arrival direction of the radio wave from each GPS satellite calculated by the absolute direction calculation means A program for causing each GPS satellite to function as a determination means for determining whether or not a received signal from each GPS satellite is multipath by comparing each GPS satellite. Position information of the GPS satellites received by GPS receiving means having a plurality of antennas for receiving radio waves from GPS satellites, and a phase difference of received signals from the GPS satellites received by each of the plurality of antennas, Acquisition means for acquiring all GPS satellites that have received radio waves;
For each GPS satellite, relative direction estimation means for estimating the relative arrival directions of radio waves from the GPS satellite based on the phase difference of the received signals from the GPS satellite acquired by the acquisition means,
For each GPS satellite, based on the position information of the GPS satellite acquired by the acquisition unit, an absolute direction calculation unit that calculates an absolute arrival direction of radio waves from the GPS satellite,
The vehicle direction estimation means for estimating the absolute reference direction of the vehicle, the relative arrival direction of the radio wave from each GPS satellite estimated by the relative direction estimation means, and the absolute direction calculation means The relative arrival direction of the radio wave from each GPS satellite, which is obtained from the absolute arrival direction of the radio wave from each GPS satellite and the absolute reference direction of the own vehicle estimated by the own vehicle direction estimating means. A program for causing each GPS satellite to function as a determination means for determining whether or not a received signal from each GPS satellite is multipath by comparing each GPS satellite.

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