阅读说明：本技术 雷达信号处理装置、雷达装置及雷达信号处理方法 (Radar signal processing device, radar device, and radar signal processing method ) 是由 古田哲朗 酒卷洋 原照幸 于 2017-12-15 设计创作，主要内容包括：碰撞判定部(404)在车辆(1000)与物体(1001)之间的多普勒速度分量变化了第1基准值为止时、或车辆(1000)移动至与第1基准值对应的距离(R)时,判定车辆(1000)是否相对于物体(1001)发生碰撞。(A collision determination unit (404) determines whether the vehicle (1000) collides with the object (1001) when the Doppler velocity component between the vehicle (1000) and the object (1001) changes by a reference value 1 or when the vehicle (1000) moves to a distance (R) corresponding to the reference value 1.)

1. A radar signal processing apparatus, comprising:

a fourier transform unit that performs fourier transform on a reception signal of a radio wave transmitted to the periphery of a vehicle and reflected from an object, thereby generating an FR map in which a signal level of the reception signal is associated with a relative distance and a relative speed between the vehicle and the object;

a peak detection unit that detects a peak of a signal intensity level based on the FR map generated by the fourier transform unit;

an orientation detection unit that detects an orientation of the object based on detection information of a peak of the signal intensity level detected by the peak detection unit;

an object position determination unit that determines whether or not the object is present at a position in a moving direction of the vehicle based on detection information of the direction detected by the direction detection unit; and

a1 st collision determination unit that determines whether or not the vehicle has collided with the object determined by the object position determination unit to be present at the position in the moving direction of the vehicle, based on data indicating a correspondence relationship between the moving speed of the vehicle and a relative distance between the object present at the position away in the direction perpendicular to the moving direction of the vehicle and the vehicle when a variation amount of a doppler velocity component of the vehicle with respect to the object present at the position away in the direction perpendicular to the moving direction of the vehicle reaches a1 st reference value, or when the vehicle moves to a distance corresponding to the 1 st reference value.

2. The radar signal processing apparatus of claim 1,

the 1 st reference value is a resolution value of a doppler velocity of the vehicle with respect to the object,

the distance corresponding to the 1 st reference value is longer as the resolution of the doppler velocity is higher or the position of the object existing above the moving direction of the vehicle is higher.

3. The radar signal processing apparatus of claim 1,

the 1 st collision determination unit determines that the vehicle does not collide with the object when the variation amount of the doppler velocity component reaches the 1 st reference value and the vehicle does not move to the distance corresponding to the 1 st reference value, and determines that the vehicle collides with the object when the variation amount of the doppler velocity component does not reach the 1 st reference value and the vehicle moves to the distance corresponding to the 1 st reference value.

4. The radar signal processing apparatus of claim 1,

the 1 st collision determination unit determines whether or not the vehicle has collided with an object present at a position distant from the vehicle in a direction perpendicular to a moving direction of the vehicle when a difference is generated between the doppler velocity component and a relative velocity between the object present in the periphery of the vehicle other than the object and the vehicle.

5. The radar signal processing apparatus of claim 4,

when the moving speed of the vehicle is low and the difference between the relative speed between the vehicle and the object and the doppler velocity component is smaller than a threshold value, it is determined that the vehicle collides with the object if the amount of change in the relative distance between the vehicle and the object monotonically decreases over time and the amount of decrease in the relative distance is equal to or greater than a2 nd reference value, and it is determined that the vehicle does not collide with the object if the amount of change in the relative distance does not monotonically decrease or the amount of decrease in the relative distance is smaller than the 2 nd reference value.

6. A radar apparatus, comprising:

an input unit that receives a radio wave transmitted to the periphery of the vehicle and reflected by the object;

an ADC unit that converts the received signal received by the input unit into a digital signal;

the radar signal processing device according to any one of claims 1, 4, and 5, which receives the received signal converted into a digital signal by the ADC unit and determines whether or not the vehicle has collided with the object; and

and an output unit that outputs the determination result obtained by the radar signal processing device.

7. A radar signal processing method, comprising:

a step in which a Fourier transform unit performs Fourier transform on a received signal of a radio wave transmitted to the periphery of a vehicle and reflected from an object, thereby generating an FR map in which the signal intensity level of the received signal is associated with the relative distance and relative speed between the vehicle and the object;

a peak detection unit that detects a peak of a signal intensity level based on the FR map generated by the fourier transform unit;

an orientation detection unit that detects an orientation of the object based on detection information of a peak of the signal intensity level detected by the peak detection unit;

an object position determination unit configured to determine whether or not the object is present at a position in a moving direction of the vehicle based on detection information of the direction detected by the direction detection unit; and

a step of determining whether or not the vehicle collides with the object determined to be present at the position in the moving direction of the vehicle by the object position determination unit, based on data indicating a correspondence relationship between the moving speed of the vehicle and a relative distance between the object present at the position away in the direction perpendicular to the moving direction of the vehicle and the vehicle when the amount of change in the doppler velocity component of the vehicle with respect to the object present at the position away in the direction perpendicular to the moving direction of the vehicle reaches a1 st reference value or when the vehicle moves to a distance corresponding to the 1 st reference value.

8. The radar signal processing method of claim 7,

the 1 st collision determination unit determines whether or not the vehicle has collided with an object present at a position distant from the vehicle in a direction perpendicular to a moving direction of the vehicle when a difference is generated between the doppler velocity component and a relative velocity between the object present in the periphery of the vehicle other than the object and the vehicle.

9. The radar signal processing method of claim 8,

when the moving speed of the vehicle is low and the difference between the relative speed between the vehicle and the object and the doppler velocity component is smaller than a threshold value, the 2 nd collision determination unit determines that the vehicle collides with the object if the amount of change in the relative distance between the vehicle and the object monotonically decreases over time and the amount of decrease in the relative distance is equal to or greater than a2 nd reference value, and determines that the vehicle does not collide with the object if the amount of change in the relative distance does not monotonically decrease or the amount of decrease in the relative distance is smaller than the 2 nd reference value.

Technical Field

The present invention relates to a radar signal processing device, and a radar device and a radar signal processing method using the same.

Background

Since the conventional vehicle-mounted radar has low accuracy in angle measurement in the height direction, an upper structure (e.g., a sign, a viaduct, a roadside tree, etc.) located at a position sufficiently higher than the vehicle height (4.5m or more) may be erroneously detected as an object on a lane. In contrast, in the radar device described in patent document 1, for example, the upper structure is determined with reference to the 1 st zero point of the directivity pattern of the antenna. The 1 st null is an elevation angle at which the reception sensitivity of the antenna is 0 between the main lobe and the 1 st side lobe of the antenna. The radar device described in patent document 1 estimates the height of the object to be detected by using: the distance from the vehicle to the occurrence of the 1 st zero point in the directivity pattern of the antenna has a proportional relationship with the height of the object to be detected.

Disclosure of Invention

Technical problem to be solved by the invention

However, in the radar device described in patent document 1, since it is necessary to approach an object to be detected until the 1 st zero point occurs in the directivity pattern of the antenna, there is a problem as follows: it takes time to determine whether or not the object to be detected is an upper structure.

For example, when the height of the object to be detected is low, if the radar device is not close enough to the object, the 1 st null is not generated in the directivity pattern of the antenna. Therefore, the radar device described in patent document 1 cannot estimate the height of the object until the 1 st zero point occurs in the directivity pattern of the antenna.

The radar device described in patent document 1 determines the 1 st zero point by a simulation assuming that the number of objects to be detected is 1.

However, in an actual environment, waveforms of signal waves reflected from a plurality of objects overlap, and therefore, it may be difficult to accurately determine the 1 st zero point.

In this case, the accuracy of estimating the height of the upper structure in the radar device described in patent document 1 is degraded.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a radar signal processing device, a radar device, and a radar signal processing method that can accurately and quickly determine a collision between a vehicle and an object existing above.

Technical scheme for solving technical problem

A radar signal processing device according to the present invention includes a Fourier transform unit, a peak detection unit, an orientation detection unit, an object position determination unit, and a1 st collision determination unit. The fourier transform unit performs fourier transform on a received signal of a radio wave transmitted to the periphery of the vehicle and reflected from an object, thereby generating an FR map in which the signal intensity level of the received signal is associated with the relative distance and the relative speed between the vehicle and the object. The peak detection unit detects a peak of the signal intensity level based on the FR map generated by the fourier transform unit. The direction detection unit detects the direction of the object based on the detection information of the peak value of the signal level detected by the peak value detection unit. The object position determination unit determines whether or not the object is present at a position in the moving direction of the vehicle based on the detection information of the direction detected by the direction detection unit. The 1 st collision determination unit determines whether the vehicle has collided with the object determined to be present at the position in the moving direction of the vehicle by the object position determination unit, based on data indicating a correspondence relationship between a moving vehicle speed of the vehicle and a relative distance between the object present at the position away in the direction perpendicular to the moving direction of the vehicle and the vehicle when a variation amount of a doppler velocity component of the vehicle with respect to the object present at the position away in the direction perpendicular to the moving direction of the vehicle reaches a1 st reference value or when the vehicle moves to a distance corresponding to the 1 st reference value.

Effects of the invention

According to the present invention, the radar signal processing device determines whether the vehicle collides with the object until the doppler velocity component between the vehicle and the object changes by the 1 st reference value or until the vehicle moves to a distance corresponding to the 1 st reference value. Thus, the radar signal processing device can accurately and quickly determine a collision between the vehicle and an object present above.

Drawings

Fig. 1 is a block diagram showing a configuration of a radar device according to embodiment 1 of the present invention.

Fig. 2A is a block diagram showing a hardware configuration for realizing the functions of the radar signal processing device according to embodiment 1. Fig. 2B is a block diagram showing a hardware configuration of software for executing functions of the radar signal processing device according to embodiment 1.

Fig. 3 is a flowchart illustrating a radar signal processing method according to embodiment 1.

Fig. 4 is a diagram showing a positional relationship between a vehicle mounted with the radar device according to embodiment 1 and an object.

Fig. 5A is a diagram showing a positional relationship between a vehicle mounted with the radar device according to embodiment 1 and an object existing above the vehicle in the traveling direction. Fig. 5B is a diagram showing a positional relationship between a vehicle mounted with the radar device according to embodiment 1 and an object present on a side of the vehicle in the traveling direction.

Fig. 6 is a graph showing a correspondence relationship between a vehicle speed of a vehicle mounted with the radar device according to embodiment 1 and a relative distance between the vehicle and an object.

Fig. 7 is a diagram showing a relationship between a position of a vehicle on which the radar device according to embodiment 1 is mounted and a position located above the vehicle in the traveling direction at a lower limit distance from a horizontal plane through which the vehicle can travel.

Fig. 8 is a flowchart showing the collision determination process in embodiment 1.

Fig. 9 is a diagram showing a positional relationship between a vehicle mounted with the radar device according to embodiment 1 and an object present at a position higher than a position of a lower limit distance from a horizontal plane through which the vehicle can pass in a traveling direction of the vehicle.

Fig. 10 is a graph showing a correspondence relationship between a vehicle speed of a vehicle and a relative distance between the vehicle and an object when a reference value of a change amount of a doppler velocity component of the vehicle mounted with the radar device according to embodiment 1 is different from that of the object.

Fig. 11 is a graph showing a correspondence relationship between a vehicle speed of a vehicle mounted with the radar device according to embodiment 1 and a relative distance between the vehicle and an object.

Fig. 12 is a block diagram showing a configuration of a radar device according to embodiment 2 of the present invention.

Fig. 13 is a diagram showing a positional relationship among a vehicle mounted with the radar device according to embodiment 2, an object existing above the vehicle in the traveling direction, and a vehicle ahead of the vehicle.

Fig. 14 is a flowchart showing a collision determination process in embodiment 2.

Fig. 15 is a graph showing a correspondence relationship between a vehicle speed, a doppler velocity with respect to an object, and a relative velocity between the vehicle and a preceding vehicle of a vehicle mounted with the radar device according to embodiment 2.

Fig. 16 is a block diagram showing a configuration of a radar device according to embodiment 3 of the present invention.

Fig. 17 is a diagram showing a positional relationship among a vehicle mounted with the radar device according to embodiment 3, an object existing above the vehicle in the traveling direction, and a vehicle ahead of the vehicle.

Fig. 18 is a diagram showing a correspondence relationship between a vehicle speed of a vehicle mounted with the radar device according to embodiment 3, a doppler velocity component of an object existing above the vehicle in a traveling direction of the vehicle, and a relative velocity between the vehicle and a preceding vehicle.

Fig. 19 is a flowchart showing a collision determination process in embodiment 3.

Fig. 20 is a graph showing a correspondence relationship between a relative distance between the vehicle and an object existing above the vehicle in the traveling direction, a relative distance between the vehicle and a preceding vehicle, and time, assuming that the vehicle speed of the vehicle on which the radar device according to embodiment 3 is mounted is constant.

Detailed Description

In the following, embodiments for carrying out the present invention will be described with reference to the accompanying drawings in order to explain the present invention in more detail.