JP7107660B2 - In-vehicle system, target object recognition method and computer program - Google Patents

Description

The present invention relates to an in-vehicle system, a target object recognition method, and a computer program.

2. Description of the Related Art Conventionally, there have been provided sensors that detect the distance to a target and the direction of the target by using the time from the transmission timing of a transmission wave to the reception timing of a reflected wave. This type of sensor can detect a so-called line-of-sight target to which the transmission wave directly reaches, but cannot detect a so-called non-line-of-sight target to which the transmission wave does not directly reach. For example, Patent Literature 1 discloses a method of estimating the position of a non-line-of-sight target using the principle of triangulation using a plurality of reflection points.

JP 2016-148547 A

However, in the method of estimating the position of a non-line-of-sight target using a reflection point, the position of a projection called a ghost that appears on an extension of a straight line connecting the sensor and the reflection point is used as the position of the target. There is a problem that false detection occurs and the presence of non-line-of-sight targets cannot be detected. Therefore, if the existence of a non-line-of-sight target cannot be detected, the start of vehicle control for avoiding collision with the target will be delayed, and safe driving cannot be sufficiently ensured.

SUMMARY OF THE INVENTION The present invention has been made in view of the circumstances described above, and an object thereof is to provide an in-vehicle system, a target recognition method, and a computer program capable of appropriately detecting the presence of non-line-of-sight targets. be.

According to the first aspect of the invention, the system-side communication unit (3) communicates with a movable target having a position information detection unit (6, 8) and a target-side communication unit (7, 9). wireless communication between The sensor (4) detects the distance to the target and the orientation of the target as detection information by at least one measurement. A reception information storage unit (2a) stores position information received by the system communication unit by transmitting position information including at least the position of the target detected by the position information detection unit from the target communication unit. is stored as received information. A target information detection unit (2b) receives detection information from the sensor a plurality of times and detects target information including the moving speed and moving direction of the target. A sensor information storage unit (2c) stores target information detected by the target information detection unit as sensor information. A comparison unit (2d) compares the received information stored in the received information storage unit and the sensor information stored in the sensor information storage unit. A non-line-of-sight determination unit (2e) determines that a target exists in the non-line-of-sight when the received information and the sensor information do not match as a result of comparison. A position estimating unit (2f) estimates the position of a target existing in the non-line-of-sight when the non-line-of-sight determining unit determines that the target exists in the non-line-of-sight. The position estimator searches for the position of the reflection point where the transmitted wave is reflected and the position of the ghost, calculates the arc cosine of the true speed specified from the received information and the radar observation speed specified from the sensor information, and calculates the arc cosine from the reflection point Calculate the arrival direction of the electromagnetic wave to the position of the target, calculate a straight line that is parallel to the calculated arrival direction of the electromagnetic wave and pass through the reflection point, and calculate the distance from the reflection point to the ghost on the straight line. A point at equal distance is estimated as the position of the target.

That is, the position information received from the target by wireless communication is stored as the reception information, and the target information detected by the sensor is stored as the sensor information, so that the reception information and the sensor information are used together. Then, when the comparison result shows that the two do not match, it is determined that the target exists in the non-line-of-sight. Focusing on the fact that the received information and sensor information do not match for targets that are out of line of sight, by comparing the received information and sensor information, it is possible to determine whether the target is in the line of sight or out of line of sight. can be judged appropriately. As a result, the presence of non-line-of-sight targets can be appropriately detected.

1 is a functional block diagram showing the overall configuration of one embodiment of the present invention; Diagram showing the relationship between radar-observed velocity and true velocity (Part 1) Diagram showing the relationship between radar-observed velocity and true velocity (part 2) Flowchart showing the processing of the microcomputer (Part 1) Flowchart showing the processing of the microcomputer (Part 2) A diagram showing the positional relationship between the target and the ghost Diagram showing the signal output time of the transmitted wave and the signal waveform of the reflected wave for comparison FIG. 4 is a diagram showing the signal output time of the transmitted wave and the signal waveform of the reflected wave according to the present invention;

An embodiment of the present invention will be described below with reference to the drawings.
An in-vehicle system 1 mounted on a vehicle M includes a microcomputer (hereinafter referred to as a microcomputer) 2, a communication unit 3 (corresponding to a system-side communication unit), a sensor 4, and a position information detection unit 5. have. An unspecified number of targets exist around the own vehicle M, and FIG. 1 illustrates a case where other vehicles N1 and N2 exist, for example. The unspecified number of targets are not limited to the other vehicles N1 and N2, but may be pedestrians, bicycles, or the like.

The other vehicle N1 has a position information detection unit 6 and a communication unit 7 (corresponding to a target side communication unit). The position information detection unit 6 has, for example, a GNSS receiver, analyzes GNSS signals received from satellites, performs positioning, and detects position information including the position of the other vehicle N1. The position information detection unit 6 may be configured to perform positioning by a method such as WiFi (Wireless Fidelity) or LTE (Long Term Evolution) without being limited to the GNSS positioning method. The communication unit 7 broadcasts the location information detected by the location information detection unit 6 . Similarly, the other vehicle N2 has a position information detection unit 8 and a communication unit 9 (corresponding to a target side communication unit). The position information detection unit 8 detects position information including the position of the other vehicle N2. The communication unit 9 broadcasts the location information detected by the location information detection unit 8 .

The communication unit 3 is a communication module installed in the own vehicle M, a portable terminal with a communication function brought into the own vehicle M by the driver, or the like. The communication unit 3 performs wireless communication with the communication unit 7 in accordance with a predetermined wireless communication standard if the host vehicle M and the other vehicle N1 are in a positional relationship in which wireless communication is possible. The position information of the other vehicle N1 is received. Similarly, the communication unit 3 performs wireless communication with the communication unit 9 according to a predetermined wireless communication standard if the host vehicle M and the other vehicle N2 are in a positional relationship in which wireless communication is possible. The position information of the other vehicle N2 broadcasted is received. Note that the predetermined wireless communication standards are, for example, WiFi, LTE, V2X (Vehicle to Everything), DSRC (Dedicated Short Range Communications), LPWA (Low Power Wide Area), and the like.

The search range in which the communication unit 3 can wirelessly communicate with the target is preferably wider than the search range in which the sensor 4, which will be described later, searches for the target, and is preferably several hundred meters, for example. It should be noted that the position information transmitted from the other vehicles N1 and N2 is not guaranteed to be accurate and may contain errors. It is difficult to do. Services relying only on position information transmitted from the other vehicles N1 and N2 are limited to information provision level services such as simply informing the driver of the presence of the other vehicles N1 and N2.

The sensor 4 is, for example, a LIDAR (Light Detection and Ranging), a milli-rear radar, a sonar, or the like, and has a configuration capable of transmitting and receiving electromagnetic waves. The sensor 4 uses the time from the transmission timing of the transmission wave to the reception timing of the reflected wave to detect the distance to the target and the azimuth of the target as detection information. The sensor 4 can detect the distance to the target and the azimuth of the target with a single measurement. requires multiple measurements.

Accuracy is guaranteed for the distance to the target and the direction of the target detected by the sensor 4, and vehicle control is performed by relying only on the distance to the target and the direction of the target detected by the sensor 4. is possible. However, the sensor 4 can detect a so-called line-of-sight target to which the transmission wave directly reaches, but cannot detect a so-called non-line-of-sight target to which the transmission wave does not directly reach. The search range of the sensor 4 depends on the transmission cycle of the transmission wave. If the transmission cycle of the transmission wave is short, the reflected wave received from a distance cannot be separated. The range is relatively narrow and the maximum detection distance is relatively short. On the other hand, if the transmission period of the transmitted wave is relatively long, the search range is relatively wide and the maximum detection distance is relatively long. The search range of the sensor 4 is, for example, about 100 m to 200 m for LIDAR and milli radar, and 10 m or less for sonar.

The position information detection unit 5, like the position information detection unit 6 of the other vehicle N1 and the position information detection unit 8 of the other vehicle N2, has, for example, a GNSS receiver, and analyzes the GNSS signal received from the satellite. Positioning is performed, and position information including the position of the own vehicle M is detected. The position information detection unit 5 is not limited to the GNSS positioning method, and may be configured to perform positioning by the WiFi or LTE method.

The microcomputer 2 has a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory) and I/O (Input/Output), and is stored in a non-transitional physical recording medium. By executing the program, the processing corresponding to the computer program is executed, and the overall operation of the in-vehicle system 1 is controlled. The microcomputer 2 includes, as internal functions realized by software or the like, a reception information storage unit 2a, a target object information detection unit 2b, a sensor information storage unit 2c, a comparison unit 2d, a non-line-of-sight determination unit 2e, a position It has an estimating unit 2f, a driving influence determining unit 2g, and a vehicle control unit 2h.

The reception information storage unit 2a inputs the unspecified number of position information from the communication unit 3 when the communication unit 3 receives the position information transmitted from the unspecified number of targets existing around the own vehicle M. Then, the input unspecified number of position information is stored as received information. That is, the reception information storage unit 2a stores the position information of the other vehicles N1 and N2, which are broadcasted from the communication units 7 and 9 of the other vehicles N1 and N2, respectively, because the other vehicles N1 and N2 exist around the own vehicle M. When received by the communication unit 3, the received positional information of the other vehicles N1 and N2 is stored as received information. The received information storage unit 2a is a cyclic memory, and when the capacity of the received information reaches the storable memory capacity, the stored old received information is erased and new received information is stored.

When the detection information is input from the sensor 4 multiple times, the target information detection unit 2b uses the detection information input multiple times to determine the moving speed and moving direction of an unspecified number of targets existing around the own vehicle M. Detect target information including In this case, the target information detection unit 2b can detect target information only for targets in the line of sight as described above. That is, the target information detection unit 2b detects the target information of the other vehicles N1 and N2 if the other vehicles N1 and N2 are present in the line of sight. The sensor information storage unit 2c stores target information detected by the target information detection unit 2b as sensor information. The sensor information storage unit 2c is also a cyclic memory similar to the received information storage unit 2a, and when the capacity of the sensor information reaches the storable memory capacity, the stored old sensor information is deleted and new sensor information is stored. memorize

The comparison unit 2d reads the reception information stored in the reception information storage unit 2a, reads the sensor information stored in the sensor information storage unit 2c, and compares the read reception information with the sensor information.

The non-line-of-sight determination unit 2e determines that a target exists in the non-line-of-sight when the received information and the sensor information do not match as a result of comparison. When the non-line-of-sight determining unit 2e determines that a target exists in the non-line-of-sight, the position estimating unit 2f estimates the position of the target existing in the non-line-of-sight.

When the position estimating unit 2f estimates the position of a target that is out of line of sight, the traveling influence determination unit 2g determines whether or not there is a possibility that the target will affect the traveling of the own vehicle. In this case, the traveling influence determination unit 2g determines whether or not there is a possibility that the target will affect the traveling of the own vehicle. Use the location information estimated by the method. The traveling influence determination unit 2g estimates the predicted course from the moving directions included in the position information of the own vehicle M and the target, and determines that the estimated predicted courses intersect or approach each other. When it is determined that there is a possibility of affecting the running of the vehicle, a control signal is output to the sensor 4, the communication section 3 and the vehicle control section 2h.

When the sensor 4 receives a control signal from the traveling influence determination unit 2g, the sensor 4 limits the search range according to the appearance point of the target. By limiting the search range, the sensor 4 can more easily detect the target than when searching the entire preset search range. Further, the sensor 4 expands the wavelength bandwidth of the transmission wave when a control signal is input from the second traveling influence determination section 2h. When the control signal is input from the travel influence determination unit 2g, the communication unit 3 transmits a warning signal to the target determined to be affected. That is, the communication unit 3 transmits a warning signal to the communication units 7 and 9 of the other vehicles N1 and N2 when the targets determined to be affected are the other vehicles N1 and N2. The vehicle control unit 2h performs vehicle control to avoid a collision between the target object and the own vehicle M when a control signal is input from the traveling influence determination unit 2g. Vehicle control for avoiding a collision is, for example, brake control and steering control, and is control for evacuating the own vehicle M to a safe place.

Here, the basic principle of the sensor 4 will be explained. The sensor 4 transmits a transmission wave composed of electromagnetic waves, and uses the propagation time, which is the time from the transmission timing of the transmission wave to the reception timing of the reflected wave, to detect the distance to the target and the orientation of the target as detection information. . Since the electromagnetic wave travels at the speed of light, the sensor 4 calculates the distance to the target according to the following formula.
Distance to target = Propagation time x Speed of light

In addition, since the frequency of the reflected wave received by the sensor 4 changes due to the Doppler effect depending on the moving speed of the target from which the transmitted wave is reflected, the frequency of the target can be determined by analyzing the frequency change between the transmitted wave and the reflected wave. Movement speed can be calculated. As shown in FIG. 2, the observation velocity observed by the sensor 4 (hereinafter referred to as radar observation velocity) is observed after vector decomposition on a straight line connecting the sensor 4 and the target. Assuming that the difference angle between the direction of the straight line connecting the sensor 4 and the target and the moving direction of the target is φ, the following formula holds between the true velocity of the target and the radar observation velocity.
Radar Observed Velocity = True Velocity x cosφ

That is, if the target moves in a straight line connecting the sensor 4 and the target, the radar observation speed is the same as the true speed. If the target moves, the radar-observed velocity slows down relative to its true velocity.

Next, the case where the target exists outside the line of sight will be described. When the target exists within the line of sight of the transmitted wave directly reaching the target, the radar observation velocity is vector-decomposed on the straight line connecting the sensor 4 and the target as shown in FIG. be done. On the other hand, there is an obstacle Z1 between the sensor 4 and the target, and the target exists outside the line of sight where the transmitted wave does not directly reach the target, and the transmitted wave is reflected by the obstacle Z2 and reaches the target. In this case, as shown in FIG. 3, the radar observed velocity is observed after vector decomposition on a straight line connecting the reflection point and the target. Also, a projection called a ghost appears on an extension line of a straight line connecting the sensor and the reflection point. Obstacles Z1 and P2 are buildings, walls, roadside trees, guardrails, parked vehicles, etc., and are synonymous with objects that block the driver's field of vision.

Next, the operation of the above configuration will be described with reference to FIGS. 4 to 8. FIG.
In the in-vehicle system 1, the microcomputer 2 performs target object recognition processing at predetermined intervals, for example, when the ignition is on. The microcomputer 2 starts target object recognition processing, and when the communication unit 3 receives the position information transmitted from an unspecified number of targets existing around the own vehicle M, the position information is transmitted from the communication unit 3. When input (S1), the received position information is stored as reception information (corresponding to S2, reception information storage step, reception information storage procedure).

In addition, when the microcomputer 2 starts target object recognition processing and inputs detection information from the sensor 4 a plurality of times (S3), it uses the detection information that has been input a plurality of times to detect a large number of unspecified objects existing around the host vehicle M. Target information including the moving speed and moving direction of the target is detected (corresponding to S4, target information detection step, target information detection procedure), and the detected target information is stored as sensor information (S5, corresponding to a sensor information storage step and a sensor information storage procedure). The microcomputer 2 performs the processing of storing received information and the processing of storing sensor information in parallel.

The microcomputer 2 reads the stored received information and sensor information, compares the read received information and sensor information (corresponding to S6, comparison step, comparison procedure), and compares the received information and sensor information. Based on the comparison result, it is determined whether or not there is a target in which the received information and sensor information do not match, and it is determined whether or not there is a target in non-line-of-sight (S7, non-line-of-sight determination step, non-line-of-sight determination procedure ). When the microcomputer 2 determines that there is no target for which the received information and the sensor information do not match, and determines that there is no target beyond the line of sight (S7: NO), it terminates the target recognition process. On the other hand, when the microcomputer 2 determines that there is a target whose received information and sensor information do not match, and determines that there is a target in the non-line-of-sight (S7: YES), it shifts to position estimation processing (S8).

When the microcomputer 2 starts the position estimation process, as shown in FIGS. 5 and 6, it searches for the position P1 of the reflection point where the transmitted wave was reflected by the obstacle Z3 and the position P2 of the ghost (S21). A distance r to the ghost is calculated (S22), and a circle C whose center is the reflection point and whose radius is the calculated distance r is calculated (S23). The microcomputer 2 identifies the true velocity Vt from the received information (S24), identifies the radar observed velocity Vg from the sensor information (S25), and calculates the difference angle φ between the true velocity Vt and the radar observed velocity Vg as follows: Calculate according to the formula (S26).
φ=arccos(Vg/Vt)

The microcomputer 2 calculates the direction rotated by the calculated angle φ from the direction of the true speed Vt at the ghost position P2 as the direction of the radar observation speed Vg, that is, the arrival direction of the electromagnetic wave from the reflection point to the target. (S27), and a straight line L parallel to the calculated direction of arrival of the electromagnetic wave and passing through the reflection point is calculated (S28). The microcomputer 2 calculates the intersection of the circle C and the straight line L, that is, the point on the straight line L at the same distance as the distance from the reflection point to the ghost (S29), and uses the calculated point as the position of the target. It is estimated as P3 (S30), and the position estimation process ends. The microcomputer 2 thus estimates the presence of the target behind the obstacle Z4.

When returning to the target object recognition process, the microcomputer 2 compares the position of the target object estimated in this way with the position of the own vehicle M detected by the position information detection unit 5, (S9). When the microcomputer 2 determines that the target may affect the running of the own vehicle M (S9: YES), it outputs a control signal to the sensor 4, the communication section 3 and the vehicle control section 2h. That is, the microcomputer 2 limits the search range of the sensor 4 (S10), expands the wavelength bandwidth of the transmission wave transmitted from the sensor 4 (S11), causes the communication unit 3 to transmit a warning signal (S12), Vehicle control is performed to avoid a collision between the target and the host vehicle M (S13), and the target recognition process is terminated.

In this way, the conventional method of recognizing a target as a moving object using only the sensor 4 cannot detect the presence of a target beyond the line of sight of the sensor 4. By applying a method of receiving the position information detected by the target object by wireless communication, the above-described problem can be solved. That is, the existence of a target beyond the line of sight of the sensor 4 can be appropriately detected.

Further, when it is determined that the target object may affect the travel of the own vehicle M, the wavelength bandwidth of the transmission wave transmitted from the sensor 4 can be expanded to increase the resolution in the distance direction, and the obstacle can be detected. It is possible to shorten the time required for recognizing a target jumping out of the shadow of a moving object as a moving object. As shown in FIG. 7, when the signal output time of the transmitted wave is relatively long, only one peak appears in the signal waveform of the reflected wave, and the obstacle Z and the pedestrian A are recognized as one target. As a result, the pedestrian A cannot be recognized. On the other hand, as shown in FIG. 8, by expanding the wavelength bandwidth of the transmission wave and relatively shortening the signal output time of the transmission wave, two peaks can appear in the signal waveform of the reflected wave. , the obstacle M and the pedestrian A can be recognized as two targets, and the pedestrian A can be recognized. 7 and 8, the transmission wave has a pulse waveform, but it may be a continuous wave such as FMCW (Frequency Modulated Continuous Wave) modulation.

As described above, according to this embodiment, the following effects can be obtained.
In the in-vehicle system 1, the position information received from the target by wireless communication is stored as the reception information, and the target information detected by the sensor is stored as the sensor information, so that the reception information and the sensor information are used together. . Then, when the comparison result shows that the two do not match, it is determined that the target exists in the non-line-of-sight. Focusing on the fact that the received information and sensor information do not match for targets that are out of line of sight, by comparing the received information and sensor information, it is possible to determine whether the target is in the line of sight or out of line of sight. can be judged appropriately. As a result, the presence of non-line-of-sight targets can be appropriately detected.

Further, in the in-vehicle system 1, when it is determined from the estimated position of the target that there is a possibility that the target may affect the traveling of the own vehicle M, the search range is limited according to the appearance point of the target. made it By limiting the search range of the sensor 4, the existence of the target can be detected immediately, and the time required to specify the position of the target can be shortened.

Further, in the in-vehicle system 1, when it is determined that there is a possibility that the target may affect the travel of the own vehicle M based on the estimated position of the target, the wavelength bandwidth of the transmission wave is expanded. By expanding the wavelength bandwidth of the transmitted wave and shortening the signal output time of the transmitted wave relatively, two peaks can appear in the signal waveform of the reflected wave, and obstacles and targets can be separated. They can be recognized as two targets, and the targets can be appropriately recognized.

Further, in the in-vehicle system 1, when it is determined from the estimated position of the target that there is a possibility that the target may affect the travel of the own vehicle M, a warning signal is transmitted. It is possible to notify the outside of the vehicle that there is a possibility that the running of the own vehicle M will be affected.

Further, when the in-vehicle system 1 determines from the estimated position of the target that there is a possibility that the target may affect the travel of the vehicle M, vehicle control is performed to avoid a collision between the target and the vehicle M. I made it to do A collision between the target and the own vehicle M can be appropriately avoided, and safe driving can be appropriately ensured.

Although the present disclosure has been described with reference to examples, it is understood that it is not limited to such examples or structures. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and configurations, as well as other combinations and configurations including single elements, more, or less, are within the scope and spirit of this disclosure.
When it is determined that the target may affect the running of the own vehicle M, and when performing vehicle control to avoid a collision between the target and the own vehicle M, the driver of the own vehicle M informs the driver of the fact. may be configured to notify to.
When it is determined that the target may affect the running of the own vehicle M, the history may be recorded and the recorded history may be transmitted to a server or the like.

In the drawing, 1 is an in-vehicle system, 1 is an in-vehicle system, 2 is a microcomputer, 2a is a reception information storage unit, 2b is a target object information detection unit, 2c is a sensor information storage unit, 2d is a comparison unit, and 2e is a non-line-of-sight determination unit. , 2f is a position estimation unit, 2g is a driving influence determination unit, 2h is a vehicle control unit, 3 is a communication unit (system side communication unit), 4 is a sensor, 6 and 8 are position information detection units, and 7 and 9 are communication units. (Target side communication unit).

Claims (8)

a system-side communication unit (3) that performs wireless communication with a movable target having a position information detection unit (6, 8) and a target-side communication unit (7, 9);
a sensor (4) that detects the distance to the target and the orientation of the target as detection information by at least one measurement;
By transmitting position information including at least the position of the target detected by the position information detection unit from the target side communication unit, the position information received by the system side communication unit is stored as received information. a received information storage unit (2a);
a target information detection unit (2b) that receives detection information from the sensor a plurality of times and detects target information including a moving speed and a moving direction of the target;
a sensor information storage unit (2c) that stores target information detected by the target information detection unit as sensor information;
a comparison unit (2d) for comparing received information stored in the received information storage unit and sensor information stored in the sensor information storage unit;
a non-line-of-sight determination unit (2e) that determines that a target exists in the non-line-of-sight when the received information and the sensor information do not match as a result of comparison;
a position estimating unit (2f) for estimating the position of the target existing in the non-line-of-sight when the non-line-of-sight determining unit determines that the target exists in the non-line-of-sight;
The position estimating unit searches for the position of the reflection point where the transmitted wave is reflected and the position of the ghost, calculates the arc cosine of the true velocity specified from the received information and the radar observation velocity specified from the sensor information, and calculates the reflection point Calculate the arrival direction of the electromagnetic wave from the target position to the position of the target, calculate a straight line that is parallel to the calculated arrival direction of the electromagnetic wave and pass through the reflection point, and the distance from the reflection point to the ghost on that straight line An in-vehicle system that estimates the position of a target as a point at a distance equal to . a travel effect determination unit (2g) that determines whether or not there is a possibility that the target that is out of line of sight will affect travel of the own vehicle when the position of the target is estimated by the position estimation unit; The in-vehicle system according to claim 1, comprising: 3. The sensor limits the search range according to the appearance point of the target when the travel effect determination unit determines that the target may affect the travel of the vehicle. In-vehicle system described in . The sensor detects the distance to the target by transmitting a transmission wave and receiving a reflected wave. 4. The in-vehicle system according to claim 2 or 3, wherein, when determined, the wavelength bandwidth of the transmission wave is expanded and the signal output time of the transmission wave is shortened. The system-side communication unit transmits a warning signal to the target-side communication unit when the running effect determination unit determines that the target may affect the running of the vehicle. 5. The in-vehicle system according to any one of items 2 to 4. Vehicle control unit (2h 6. The in-vehicle system according to any one of claims 2 to 5, comprising: In the microcomputer (2) of the in-vehicle system (1),
a received information storage step of storing the received position information as received information by transmitting position information including at least the position of the target from the target;
A target that detects target information including the moving speed and moving direction of the target by inputting detection information multiple times from a sensor that detects the distance to the target and the direction of the target as detection information by at least one measurement. an information detection step;
a sensor information storage step of storing target information detected by the target information detection step as sensor information;
a comparing step of comparing the received information stored by the received information storing step and the sensor information stored by the sensor information storing step;
a non-line-of-sight determination step of determining that a target exists in the non-line-of-sight when the received information and the sensor information do not match as a result of comparing the received information and the sensor information;
a position estimation step of estimating the position of the target existing in the non-line-of-sight when the non-line-of-sight determination step determines that the target exists in the non-line-of-sight;
The position estimating step searches for the position of the reflection point where the transmitted wave is reflected and the position of the ghost, calculates the arc cosine of the true speed specified from the received information and the radar observation speed specified from the sensor information, and calculates the reflection point Calculate the arrival direction of the electromagnetic wave from the target position to the position of the target, calculate a straight line that is parallel to the calculated arrival direction of the electromagnetic wave and pass through the reflection point, and the distance from the reflection point to the ghost on that straight line A target recognition method that estimates a point at a distance equal to , as the position of the target. A system-side communication unit (3) that performs wireless communication with a movable target having a position information detection unit (6, 8) and a target-side communication unit (7, 9), and at least one measurement In the microcomputer (2) of the in-vehicle system (1) equipped with a sensor (4) that detects the distance to the target and the direction of the target as detection information by
By transmitting position information including at least the position of the target detected by the position information detection unit from the target side communication unit, the position information received by the system side communication unit is stored as received information. a received information storage procedure;
a target information detection procedure for inputting detection information from the sensor a plurality of times and detecting target information including a moving speed and a moving direction of the target;
a sensor information storage procedure for storing target information detected by the target information detection procedure as sensor information;
a comparing procedure for comparing the received information stored by the received information storing procedure and the sensor information stored by the sensor information storing procedure;
a non-line-of-sight determination procedure for determining that a target exists in the non-line-of-sight when the received information and the sensor information do not match as a result of comparison;
a position estimation procedure for estimating the position of the target existing in the non-line-of-sight when the non-line-of-sight determination procedure determines that the target exists in the non-line-of-sight;
The position estimation procedure searches for the position of the reflection point where the transmitted wave is reflected and the position of the ghost, calculates the arc cosine of the true speed specified from the received information and the radar observation speed specified from the sensor information, and calculates the reflection point Calculate the arrival direction of the electromagnetic wave from the target position to the position of the target, calculate a straight line that is parallel to the calculated arrival direction of the electromagnetic wave and pass through the reflection point, and the distance from the reflection point to the ghost on that straight line A computer program that estimates the position of a target as a point at a distance equal to .

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