WO2022014269A1 - Vehicular radar system and vehicle - Google Patents

Abstract

A vehicular radar system installed in a vehicle (1) comprises: a radar (6) that is configured so as to acquire information indicating the environment around the vehicle by emitting radio waves outward of the vehicle (1); and a radar control unit that is configured so as to control the radar (6) such that an emission direction (K) of the radio waves changes in the vertical direction of the radar (6) in accordance with the inclination of the vehicle (1) with respect to a road surface (R) facing the vehicle (1).

Description

Vehicle radar system and vehicle

This disclosure relates to vehicle radar systems and vehicles.

Currently, research on autonomous driving technology for automobiles is being actively conducted in each country, and legislation has been established to enable vehicles (hereinafter, "vehicles" refers to automobiles) to drive on public roads in automatic driving mode. Is being considered in each country. Here, in the automatic driving mode, the vehicle system automatically controls the running of the vehicle. Specifically, in the automatic driving mode, the vehicle system controls steering based on information indicating the surrounding environment of the vehicle (surrounding environment information) obtained from sensors such as a camera and a radar (for example, a laser radar or a millimeter wave radar). At least one of (control of the traveling direction of the vehicle), brake control and accelerator control (control of vehicle braking and acceleration / deceleration) is automatically performed. On the other hand, in the manual driving mode described below, the driver controls the running of the vehicle, as is the case with many conventional vehicles. Specifically, in the manual driving mode, the running of the vehicle is controlled according to the driver's operation (steering operation, brake operation, accelerator operation), and the vehicle system does not automatically perform steering control, brake control, and accelerator control. The vehicle driving mode is not a concept that exists only in some vehicles, but a concept that exists in all vehicles including conventional vehicles that do not have an automatic driving function. For example, vehicle control. It is classified according to the method and the like.

In this way, in the future, vehicles traveling in the automatic driving mode on public roads (hereinafter, appropriately referred to as "automated driving vehicles") and vehicles traveling in the manual driving mode (hereinafter, appropriately referred to as "manual driving vehicles"). It is expected that) will be mixed.

As an example of the automatic driving technique, Patent Document 1 discloses an automatic following driving system in which a following vehicle automatically follows the preceding vehicle. In the automatic follow-up driving system, each of the preceding vehicle and the following vehicle is equipped with a lighting system, and text information for preventing another vehicle from interrupting between the preceding vehicle and the following vehicle is added to the lighting system of the preceding vehicle. At the same time, text information indicating that the vehicle is automatically following is displayed on the lighting system of the following vehicle.

Japanese Patent Application Laid-Open No. 9-2778787

By the way, with the development of autonomous driving technology, it is necessary to dramatically improve the detection accuracy of the surrounding environment of the vehicle. By mounting a camera, millimeter-wave radar, and LiDAR unit on the vehicle to detect the surrounding environment of the vehicle, it is possible to dramatically improve the detection accuracy of the surrounding environment of the vehicle.

On the other hand, if the vehicle is tilted with respect to the road surface due to changes in the movement of the center of gravity of the vehicle, the radio waves emitted from the millimeter-wave radar may not be emitted toward the vehicle in front of the vehicle, or the radio waves may be emitted. Is assumed to be emitted toward an object such as a signboard in the sky. Specifically, when the beam direction of the radio wave is tilted with respect to the road surface, the signboard in the sky is mistakenly recognized as a vehicle in front from the radar data output from the millimeter-wave radar, or the vehicle in front is the object. It is assumed that the situation is not detected as. In particular, when the long-distance millimeter-wave radar is tilted with respect to the road surface, it is assumed that radio waves will not be emitted toward an object located far from the vehicle. It is expected that the adverse effect on the output radar data will be large. From the above viewpoint, there is room for study on a vehicle radar system capable of suppressing a decrease in reliability of the radar mounted on the vehicle even when the vehicle is tilted with respect to the road surface.

It is an object of the present disclosure to provide a radar system for a vehicle and a vehicle capable of suppressing a decrease in reliability of a radar mounted on the vehicle even when the vehicle is tilted with respect to a road surface.

The vehicle radar system mounted on the vehicle according to one aspect of the present disclosure is
A radar configured to acquire information indicating the surrounding environment of the vehicle by emitting radio waves toward the outside of the vehicle.
The radar control unit is configured to control the radar so as to change the emission direction of the radio wave in the vertical direction of the radar according to the inclination of the vehicle with respect to the road surface facing the vehicle.

According to the above configuration, the emission direction of radio waves in the vertical direction of the radar changes according to the inclination of the vehicle. For this reason, even if the vehicle tilts with respect to the road surface as a result of the movement of the center of gravity of the vehicle, the radio waves emitted from the radar are not emitted toward the vehicle in front of the vehicle, or the radio waves are in the sky. It is possible to suitably prevent a situation in which a radio wave is emitted toward an object such as a signboard. In particular, when the direction of radio wave emission is tilted with respect to the road surface, the signboard in the sky is mistakenly recognized as a vehicle in front from the surrounding environment information acquired by the radar, or the vehicle in front is not detected as an object. Is assumed. On the other hand, the vehicle radar system can prevent these situations. Therefore, even when the vehicle is tilted with respect to the road surface, it is possible to provide a radar system for a vehicle that can suppress a decrease in reliability of a radar mounted on the vehicle.

Further, a vehicle provided with a tilt sensor configured to detect the tilt of the vehicle with respect to the road surface facing the vehicle and the radar system for the vehicle may be provided.

According to the present disclosure, it is possible to provide a radar system for a vehicle and a vehicle capable of suppressing a decrease in reliability of a radar mounted on the vehicle even when the vehicle is tilted with respect to a road surface.

A front view of a vehicle according to an embodiment of the present invention (hereinafter referred to as the present embodiment) is shown. It is a block diagram which shows the vehicle system which concerns on this embodiment. It is a block diagram which shows the structure of a radar. It is a schematic diagram which shows the transmitting antenna, the receiving antenna, and the transmitting side RF circuit. It is a flowchart for demonstrating the process of changing the emission direction of a radio wave according to the inclination of a vehicle with respect to a road surface. The emission direction of radio waves when the vehicle is parallel to the road surface is shown. Indicates the emission direction of radio waves when the vehicle is tilted with respect to the road surface. It is a figure for demonstrating how the emission direction of a radio wave changes from the state which is tilted with respect to a road surface to the state which is parallel to a road surface when a vehicle is tilted with respect to a road surface. A diagram showing how radio waves emitted from a radar mounted on a vehicle (radio waves whose emission direction is tilted with respect to the road surface and radio waves whose emission direction is parallel to the road surface) are emitted toward the vehicle ahead. Is.

Hereinafter, an embodiment of the present disclosure (hereinafter, simply referred to as “the present embodiment”) will be described with reference to the drawings. The dimensions of each member shown in this drawing may differ from the actual dimensions of each member for convenience of explanation.

Further, in the description of the present embodiment, for convenience of explanation, the "left-right direction", "front-back direction", and "vertical direction" of the vehicle 1 may be appropriately referred to. These directions are relative directions set for the vehicle 1 shown in FIG. Here, the "left-right direction" is a direction including the "left direction" and the "right direction". The "vertical direction" is a direction including "upward" and "downward". Although the front-rear direction is not shown in FIG. 1, the front-back direction is a direction orthogonal to the left-right direction and the up-down direction.

Further, the horizontal direction D1 and the vertical direction D2 of the radar 6 mounted on the vehicle 1 may be appropriately referred to. These are the relative directions set for the radar 6 shown in FIG. In the present embodiment, it is assumed that the vertical direction D2 of the radar 6 is parallel to the vertical direction of the vehicle 1. It is assumed that the horizontal direction D1 of the radar 6 is parallel to the left-right direction and the front-back direction of the vehicle 1.

First, the vehicle 1 and the vehicle system 2 according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 shows a front view of a vehicle 1 provided with a vehicle system 2. FIG. 2 is a block diagram showing the vehicle system 2.

As shown in FIG. 1, the vehicle 1 is a vehicle (automobile) capable of traveling in the automatic driving mode. As shown in FIG. 2, the vehicle system 2 includes a vehicle control unit 3, a left side lighting unit 4L, a right side lighting unit 4R, a lighting control unit 20, a tilt sensor 7, and a radar system 10. The vehicle system 2 further includes an HMI (Human Machine Interface) 8, a GPS (Global Positioning System) 9, and a wireless communication module 12.

The vehicle control unit 3 is configured to control the running of the vehicle 1. The vehicle control unit 3 is composed of, for example, at least one electronic control unit (ECU: Electronic Control Unit). The electronic control unit includes a computer system including one or more processors and one or more memories (for example, SoC (System on a Chip) or the like), and an electronic circuit composed of active elements such as transistors and passive elements. The processor includes, for example, at least one of a CPU (Central Processing Unit), an MPU (Micro Processing Unit), a GPU (Graphics Processing Unit), and a TPU (Tensor Processing Unit). The CPU may be composed of a plurality of CPU cores. The GPU may be composed of a plurality of GPU cores. The memory includes a ROM (Read Only Memory) and a RAM (Random Access Memory). The vehicle control program may be stored in the ROM. For example, the vehicle control program may include an artificial intelligence (AI) program for autonomous driving. An AI program is a program (trained model) constructed by supervised or unsupervised machine learning (particularly deep learning) using a multi-layer neural network. The RAM may temporarily store a vehicle control program, vehicle control data, and / or peripheral environment information indicating the surrounding environment of the vehicle. The processor may be configured to develop a program designated from various vehicle control programs stored in the ROM on the RAM and execute various processes in cooperation with the RAM. Further, the computer system may be configured by a non-Von Neumann computer such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array).

The left side lighting unit 4L is arranged on the left front side of the vehicle 1 and is configured to emit a light distribution pattern toward the front region of the vehicle 1. The right lighting unit 4R is arranged on the right front side of the vehicle 1 and is configured to emit a light distribution pattern toward the front region of the vehicle 1. The lighting control unit 20 is configured to control the drive of each of the left side lighting unit 4L and the right side lighting unit 4R. The lighting control unit 20 is composed of, for example, an electronic control unit.

The tilt sensor 7 is mounted on the vehicle 1 and is configured to detect the tilt of the vehicle 1 with respect to the road surface R (see FIGS. 6A and 6B) facing the vehicle 1. In particular, the tilt sensor 7 detects the tilt of the central axis Ax of the vehicle 1 with respect to the road surface R, as shown in FIGS. 6A and 6B. Here, the central axis Ax of the vehicle 1 is parallel to the front-rear direction of the vehicle 1 and is an axis perpendicular to the vertical direction and the left-right direction of the vehicle 1. For example, as shown in FIG. 6A, when the center of gravity of the vehicle 1 has not changed, the central axis Ax is parallel to the road surface R. On the other hand, as shown in FIG. 6B, when the center of gravity of the vehicle 1 is changed due to the presence of occupants and luggage in the rear seats of the vehicle 1, the central axis Ax has a predetermined angle with respect to the road surface R. Just lean. The tilt sensor 7 is, for example, a vehicle height sensor, an acceleration sensor, or a gyro sensor. The tilt sensor 7 is configured to transmit tilt data indicating the tilt of the vehicle 1 with respect to the road surface R to the vehicle control unit 3.

In the present embodiment, the tilt sensor 7 is directly connected to the vehicle control unit 3, but the tilt sensor 7 is directly connected to the lighting control unit 20 and the radar control unit 5 instead of the vehicle control unit 3. May be good.

The radar system 10 includes a radar 6 and a radar control unit 5. The radar 6 is configured to acquire information (radar data) indicating the surrounding environment of the vehicle 1 by emitting radio waves toward the front of the vehicle 1. The radar 6 may be arranged, for example, behind the front bumper 50 of the vehicle 1. In particular, the radar 6 may be arranged behind the emblem of the vehicle 1 mounted on the front bumper 50. In this respect, the radar 6 is preferably arranged on an axis passing through the center of the vehicle 1 in the left-right direction.

The radar 6 is, for example, a millimeter wave radar or a microwave radar. The radar 6 functions as a medium-range radar or a long-range radar capable of acquiring information on an object (another vehicle, a pedestrian, etc.) existing at a position away from the vehicle 1. The maximum detection distance of the radar 6 is, for example, in the range of 150 m to 250 m. The vertical field of view of the radar 6 is ± 5 °, and the horizontal field of view of the radar 6 is ± 10 °. The specific configuration of the radar 6 will be described later.

The radar control unit 5 is configured to control the drive of the radar 6. Further, the radar control unit 5 acquires radar data from the radar 6 and then acquires the surrounding environment information of the vehicle 1 based on the radar data. The surrounding environment information may include, for example, information on the distance and direction of the object with respect to the vehicle 1 and information on the relative speed of the object with respect to the vehicle 1.

The radar control unit 5 is composed of at least one electronic control unit (ECU). The electronic control unit includes a computer system (for example, SoC) including one or more processors and one or more memories, and an electronic circuit composed of active elements such as transistors and passive elements. The processor includes at least one of CPU, MPU, GPU and TPU. The memory includes a ROM and a RAM. Further, the computer system may be configured by a non-Von Neumann computer such as an ASIC or FPGA.

The HMI 8 is composed of an input unit that receives an input operation from the driver and an output unit that outputs driving information and the like to the driver. The input unit includes a steering wheel, an accelerator pedal, a brake pedal, an operation mode changeover switch for switching the operation mode of the vehicle 1, and the like. The output unit is a display (for example, Head Up Display (HUD) or the like) that displays various driving information. The GPS 9 is configured to acquire the current position information of the vehicle 1 and output the acquired current position information to the vehicle control unit 3.

The wireless communication module 12 is configured to receive information about other vehicles in the vicinity from the other vehicle and transmit information about the vehicle 1 to the other vehicle (vehicle-to-vehicle communication). Further, the wireless communication module 12 is configured to receive infrastructure information from traffic infrastructure equipment such as traffic lights and indicator lights and to transmit traveling information of vehicle 1 to the traffic infrastructure equipment (road-to-vehicle communication). Further, the wireless communication module 12 is configured to receive information about the pedestrian from a mobile terminal such as a smartphone carried by the pedestrian and to transmit the traveling information of the vehicle 1 to the mobile terminal (pedestrian-to-vehicle communication). .. Further, the vehicle 1 can receive predetermined information from a server on a communication network such as the Internet via the wireless communication module 12.

In the present embodiment, the vehicle 1 is equipped with a radar 6 that functions as a medium-range radar or a long-range radar as a sensing device that acquires information indicating the surrounding environment of the vehicle 1. On the other hand, the vehicle 1 may further include not only the radar 6 but also a camera, a LiDAR unit and a short-range radar. In this case, the camera, LiDAR unit and short range radar may be located at each of the four corners of vehicle 1.

(Radar configuration)
Next, a specific configuration of the radar 6 will be described below with reference to FIGS. 3 and 4. As shown in FIG. 3, the radar 6 includes a transmitting antenna 65, a receiving antenna 66, a transmitting side RF (radio frequency) circuit 61, a receiving side RF circuit 62, and a signal processing circuit 63. In this embodiment, the radar 6 is configured as a phased array type radar.

The transmitting antenna 65 is configured to radiate millimeter waves, which are radio waves having a wavelength of 1 mm to 10 mm, in the air, for example. The receiving antenna 66 is configured to receive reflected radio waves radiated from the transmitting antenna 65 and reflected by an object (for example, another vehicle or the like) existing outside the vehicle 1.

As shown in FIG. 4, the transmitting antenna 65 may be composed of a plurality of transmitting antenna elements 165 (patch antenna elements) formed on the antenna substrate 67 and arranged in 4 rows × 3 columns. Specifically, the four transmitting antenna elements 165 are arranged in the vertical direction D2, and the three transmitting antenna elements 165 are arranged in the horizontal direction D1. Each transmitting antenna element 165 constituting the transmitting antenna 65 is configured to receive a high frequency signal (TX signal) from the transmitting side RF circuit 61 and then radiate radio waves toward the air.

The receiving antenna 66 may be formed, for example, by a plurality of receiving antenna elements 166 (patch antenna elements) formed on the antenna board 67 and arranged in 4 rows × 4 columns. Specifically, the four receiving antenna elements 166 are arranged in the vertical direction D2, and the four receiving antenna elements 166 are arranged in the horizontal direction D1. Each receiving antenna element 166 constituting the transmitting antenna 65 receives the reflected radio wave reflected by the object and outputs a weak high frequency signal (RX signal) corresponding to the reflected radio wave to the receiving side RF circuit 62. It is configured in.

In this embodiment, the number of arrangements of the transmitting antenna element 165 and the number of arrangements of the receiving antenna element 166 are merely examples.

The transmitting side RF circuit 61, the receiving side RF circuit 62, and the signal processing circuit 63 are configured as a monolithic microwave integrated circuit (MMIC). The transmitting side RF circuit 61 is electrically connected to the transmitting antenna 65 and is configured to supply a high frequency signal to the transmitting antenna 65. The transmission side RF circuit 61 includes a high frequency generation circuit 160 that generates a high frequency signal, phase detectors 162a to 162d that adjust the phase of the high frequency signal, and amplifiers 163a to 163d. When the radar 6 is a radar that adopts the FMCW method, the high frequency generation circuit 160 generates a chirp signal (FMCW signal) whose frequency changes linearly with the passage of time.

The receiving side RF circuit 62 is electrically connected to the receiving antenna 66 and is configured to receive a weak high frequency signal from the receiving antenna 66. The receiving side RF circuit 62 includes an amplifier, a mixer, a bandpass filter, an AD converter, and a filter circuit. The amplifier is configured to amplify a weak high frequency signal output from the receiving antenna 66. The mixer generates an intermediate frequency (IF) signal by mixing the high frequency signal (RX signal) output from the amplifier and the high frequency signal (TX signal) output from the high frequency generation circuit 160. The AD converter is configured to convert an IF signal that has passed through a bandpass filter from an analog signal to a digital signal. The digital signal is transmitted to the signal processing circuit 63 via the filter circuit.

The signal processing circuit 63 is configured to control the transmitting side RF circuit 61 and the receiving side RF circuit 62 according to the control signal from the radar control unit 5. Further, the signal processing circuit 63 generates radar data by signal processing (for example, fast Fourier transform processing) the digital signal output from the receiving side RF circuit 62, and then radar-controls the generated radar data. It is configured to be transmitted to the unit 5. The signal processing circuit 63 includes, for example, a DSP (Digital Signal Processor) and a microcomputer composed of a processor and a memory.

In the present embodiment, the phase detectors 162a to 162d control the phase of the high frequency signal (TX signal) to control the emission direction K in the vertical direction D2 of the radio wave radiated from the transmission antenna 65. In particular, by controlling the phase of the TX signal, it is possible to change the beam direction in the vertical direction D2 of the synthesized radio wave configured by synthesizing each radio wave radiated from each transmitting antenna element 165. In the present embodiment, the emission direction K of the radio wave radiated from the radar 6 corresponds to the emission direction of the beam central axis of the synthetic radio wave.

In this respect, the phase detector 162a is the phase of the TX signal Sa input to the transmit antenna element group 165a composed of the three transmit antenna elements 165 arranged in the fourth row of the 12 transmit antenna elements 165. To adjust. The phase detector 162b adjusts the phase of the TX signal Sb input to the transmission antenna element group 165b composed of the three transmission antenna elements 165 arranged in the third row. The phase detector 162c adjusts the phase of the TX signal Sc input to the transmission antenna element group 165c composed of the three transmission antenna elements 165 arranged in the second row. The phase detector 162d adjusts the phase of the TX signal Sd input to the transmission antenna element group 165d composed of the three transmission antenna elements 165 arranged in the first row.

In particular, the signal processing circuit 63 adjusts the phases of the TX signals Sa to Sd by controlling the phase devices 162a to 162d. In particular, the signal processing circuit 63 includes a phase difference between the phase of the TX signal Sa and the phase of the TX signal Sb, a phase difference between the phase of the TX signal Sb and the phase of the TX signal Sc, and the TX signal Sc. The phase difference between the phase and the phase of the TX signal Sd is adjusted. In this way, the signal processing circuit 63 can control the emission direction K in the vertical direction D2 of the radio wave radiated from the transmission antenna 65.

Next, the process of changing the radio wave emission direction K in the vertical direction D2 of the radar 6 according to the inclination of the vehicle 1 with respect to the road surface R will be described with reference to FIGS. 5 to 8. FIG. 5 is a flowchart for explaining a process of changing the emission direction K of the radio wave according to the inclination of the vehicle 1 with respect to the road surface R. As described above, it is assumed that the vertical direction D2 of the radar 6 is parallel to the vertical direction of the vehicle 1 and the horizontal direction D1 of the radar 6 is parallel to the horizontal direction and the front-rear direction of the vehicle 1.

As shown in FIG. 5, in step S1, the radar control unit 5 acquires inclination information indicating the inclination angle θ of the vehicle 1 with respect to the road surface R from the vehicle control unit 3. Specifically, first, the vehicle control unit 3 acquires tilt data indicating the tilt of the central axis Ax (see FIGS. 6A and 6B) of the vehicle 1 with respect to the road surface R from the tilt sensor 7, and then acquires the tilt data. Based on the inclination data, the inclination angle θ of the central axis Ax of the vehicle 1 with respect to the road surface R is specified. After that, the vehicle control unit 3 transmits the inclination information indicating the inclination angle θ to the radar control unit 5.

Further, it is assumed that the emission direction K of the radio wave radiated from the radar 6 is parallel to the central axis Ax of the vehicle 1. Therefore, as shown in FIG. 6A, when the central axis Ax of the vehicle 1 is parallel to the road surface R, the emission direction K of the radio wave radiated from the radar 6 is also parallel to the road surface R. Will be. On the other hand, as shown in FIG. 6B, when the central axis Ax of the vehicle 1 is tilted with respect to the road surface R, the emission direction K of the radio wave radiated from the radar 6 is also tilted with respect to the road surface R. .. Therefore, when the vehicle 1 is tilted with respect to the road surface R, the radio wave emission direction K is also tilted, so that the radar 6 accurately detects an object such as a vehicle in front that exists at a position away from the vehicle 1. It is assumed that the situation cannot be achieved.

Next, in step S2, the radar control unit 5 radars so that the emission direction K of the radio wave radiated from the radar 6 is parallel to the road surface R based on the inclination angle θ of the central axis Ax with respect to the road surface R. 6 is controlled. At this point, when the central axis Ax is tilted by an angle θ with respect to the road surface R, the emission direction K of the radio wave radiated from the radar 6 is also tilted by an angle θ with respect to the road surface R. Therefore, the radar control unit 5 controls the radar 6 so that the radio wave emission direction K is parallel to the road surface R and the radio wave emission direction K in the vertical direction D2 is tilted by an angle θ. Specifically, the radar control unit 5 transmits to the radar 6 a control signal instructing the emission direction K of the radio wave in the vertical direction D2 to be tilted by an angle θ. The signal processing circuit 63 of the radar 6 controls each phase device 162a to 162d so that the emission direction K of the radio wave in the vertical direction D2 is tilted by an angle θ based on the control signal received from the radar control unit 5. As described above, as shown in FIG. 7, the radio wave emission direction K in the vertical direction D2 is tilted by the angle θ, so that the radio wave emission direction K is parallel to the road surface R.

According to this embodiment, the emission direction K in the vertical direction D2 of the radio wave radiated from the radar 6 changes according to the inclination of the vehicle 1 with respect to the road surface R. Therefore, as a result of the movement of the center of gravity of the vehicle 1, even if the vehicle 1 is tilted with respect to the road surface R, the radio waves radiated from the radar 6 irradiate the object existing at a position away from the vehicle 1. It is possible to suitably prevent a situation in which the radio wave is not performed or a situation in which the radio wave is irradiated to a guide plate or a signboard existing in the sky. In particular, when the radio wave emission direction K is tilted with respect to the road surface R, the signboard in the sky is erroneously recognized as a vehicle in front based on the radar data generated from the radar 6, and the vehicle in front is It is possible to suitably prevent a situation where the object cannot be detected. As described above, it is possible to provide the radar system 10 capable of suppressing the deterioration of the reliability of the radar 6 even when the vehicle 1 is tilted with respect to the road surface R.

For example, as shown in FIG. 8, when the emission direction K of the radio wave radiated from the radar 6 is tilted with respect to the road surface R (emission direction K shown by the broken line), the radio wave exists at a position away from the vehicle 1. As a result of not irradiating the front vehicle 1A with radio waves, it is assumed that the radar 6 cannot detect the front vehicle 1A. On the other hand, when the emission direction K is parallel to the road surface R (the emission direction K shown by the solid line), the front vehicle 1A can be irradiated with radio waves, so that the radar 6 can reliably detect the front vehicle 1A. Is possible.

Further, in the present embodiment, the emission direction K in the vertical direction D2 of the radio wave radiated from the radar 6 is adjusted by adjusting the phase of the TX signal input to each of the transmitting antenna element groups 165a to 165d constituting the transmitting antenna 65. Can be controlled. Therefore, it is not necessary to separately provide a mechanical drive mechanism in the radar system 10 for changing the emission direction K in the vertical direction D2 of the radio wave. In this way, the radar system 10 can be miniaturized, and the overall manufacturing cost of the radar system 10 can be reduced.

Although the embodiments of the present invention have been described above, it goes without saying that the technical scope of the present invention should not be construed in a limited manner by the description of the present embodiments. It is understood by those skilled in the art that the present embodiment is merely an example, and various embodiments can be modified within the scope of the invention described in the claims. The technical scope of the present invention should be determined based on the scope of the invention described in the claims and the scope thereof.

In the present embodiment, the radar control unit 5 controls the radar 6 so that the emission direction K of the radio wave radiated from the radar 6 is parallel to the road surface R, but the emission direction K of the radio wave is. It does not have to be completely parallel to the road surface R. In this respect, the radar control unit 5 may control the radar 6 so that the inclination angle θ of the radio wave emission direction K with respect to the road surface R is within the range of 0 ° ≦ θ ≦ 5 °. As described above, the "state in which the emission direction K of the radio wave is parallel to the road surface R" is not only a state in which the emission direction K is completely parallel to the road surface R, but also the emission direction K with respect to the road surface R. Also includes a state in which the inclination angle θ of is within the range of 0 ° ≦ θ ≦ 5 °.

Further, in the present embodiment, the radar control unit 5 and the vehicle control unit 3 are configured by separate electronic control units, but the present embodiment is not limited to this. In this respect, the radar control unit 5 and the vehicle control unit 3 may be configured by one electronic control unit.

This application appropriately incorporates the contents disclosed in the Japanese patent application (Japanese Patent Application No. 2020-121503) filed on July 15, 2020.

Claims (4)

It is a vehicle radar system installed in a vehicle.
A radar configured to acquire information indicating the surrounding environment of the vehicle by emitting radio waves toward the outside of the vehicle.
The radar control unit is configured to control the radar so as to change the emission direction of the radio wave in the vertical direction of the radar according to the inclination of the vehicle with respect to the road surface facing the vehicle. , Vehicle radar system. The radar is
A transmitting antenna having a plurality of transmitting antenna elements in the vertical direction and emitting the radio wave toward the outside of the vehicle, and a transmitting antenna.
A receiving antenna having a plurality of receiving antenna elements in the vertical direction and receiving the radio wave reflected by an object existing outside the vehicle, and a receiving antenna.
A transmission side RF circuit that is electrically connected to the transmission antenna and supplies a first high frequency signal to each of the plurality of transmission antenna elements.
A receiving-side RF circuit that is electrically connected to the receiving antenna, receives a second high-frequency signal from each of the plurality of receiving antenna elements, and then converts the second high-frequency signal into a digital signal.
A signal processing circuit that processes the digital signal output from the receiving side RF circuit, and
Equipped with
The radar control unit
The first aspect of the present invention is configured to change the emission direction of the radio wave emitted from the transmission antenna by controlling the phase of the first high frequency signal supplied to each of the plurality of transmission antenna elements. The vehicle radar system described. The vehicle radar system according to claim 1 or 2, wherein the radar control unit is configured to control the radar so that the emission direction of the radio wave in the vertical direction is parallel to the road surface. A tilt sensor configured to detect the tilt of the vehicle with respect to the road surface facing the vehicle, and
The vehicle radar system according to any one of claims 1 to 3.
A vehicle equipped with.

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