JPH02287178A - On-vehicle radar system - Google Patents

Abstract

PURPOSE:To obtain the speed of a moving body and the distance to a precedent body by one antenna system at the same time by switching the phase shift quantities of phase shifters and directing the beam of an antenna in a downward and a front direction alternately. CONSTITUTION:A phased array antenna is composed of plural antenna elements 1 and plural phase shifters 2. Then the phase shift quantities of the phase shifters 2 are switched by a switching device 4 to switch the beam of the antenna between a ground beam and a front beam alternately. A transmitter receiver 3 inputs a reflected wave received by the antenna 1 to obtain data on the speed of the moving body when the antenna is in the ground beam state or the distance between moving bodies or to an obstacle when in the front beam state. Consequently, the speed of the moving body and the distance and relative speed to the precedent body are easily obtained by one antenna system at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an on-vehicle radar system using a needed array antenna (mounted on a moving object such as an automobile).

[Prior Art] Many conventional vehicle-mounted radar systems use a horn antenna, a waveguide slot antenna, or the like as an antenna.

[Problem to be solved by the invention] In the above radar system, it is necessary to direct the antenna beam downward in order to determine the ground speed, which is the speed of a moving object. To determine the distance or relative velocity between bodies, it is necessary to direct the antenna beam forward. Therefore, two types of antenna systems are required to obtain the above two types of data. In addition, changing the beam of the antenna using a mechanical drive device requires a very large scale.

The present invention has been provided in view of the above-mentioned points, and uses a plurality of antenna elements and a phase shifter to electrically switch antenna beams to adjust the speed of a moving object and the distance between moving objects. The object of the present invention is to provide an on-vehicle radar system that can simultaneously determine relative speed using one antenna system.

In addition, for other purposes, when determining the speed of a moving object,
The purpose is to eliminate as much as possible the effects of road surfaces such as potholes and steps.

[Means for Solving the Problems] The present invention provides a phased array antenna including a plurality of antenna elements and a plurality of phase shifters mounted on a moving body such as a vehicle, and an output of the phased array antenna that receives reflected waves. The transmitting/receiving device detects the speed of moving objects, the distance between moving objects, the distance between moving objects and obstacles, etc., and the phase shift amount of the phase shifter is switched to control the angle of the beam from the antenna element. It is equipped with a switching device that

Furthermore, it is equipped with an arithmetic device that averages a plurality of pieces of speed data outputted from the transmitting/receiving device to detect the speed, etc. of the moving body.

Furthermore, as means for averaging the speed data etc. by the arithmetic unit, a data discrimination device is provided to remove abnormal data.

Further, as a means for detecting the speed of the moving body of the transmitting/receiving device, an antenna beam control device is provided which shapes a plurality of antenna beams having different ground angles obtained by switching the phase shift amount of the phase shifter in multiple stages using the switching device. The arithmetic unit averages a plurality of speed data having different ground angles.

[Function] Accordingly, in the present invention, the amount of phase shift of the phase shifter is switched by a switching device so that the beam of the antenna is directed alternately in two directions, ie, the downward direction and the front direction. The transmitter/receiver uses the transmitted and received signals to obtain data such as the speed of the moving objects, the distance between the moving objects or between the moving objects and the obstacle, and the relative speed.

Further, in claim 2, in order to eliminate the influence of road surfaces such as potholes and steps, a plurality of consecutive speed data and the like are averaged using an arithmetic device.

Furthermore, in claim 3, when abnormal data that is considered to be caused by scattered waves etc. appears, the data is sorted by a data judgment device so as to remove data that has changed by a certain value or more, and then averaged. We are trying to obtain more accurate speed data, etc.

Further, in claim 4, the switching device and the antenna beam control device switch the phase shift amount of the phase shifter into multiple stages, and use speed data obtained from a plurality of antenna beams having different ground speeds, Similarly, the speed data is averaged to obtain highly accurate speed data.

[Example 1] Example 1 of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration diagram of Embodiment 1, in which a 7-aided array antenna is composed of a plurality of antenna elements 1 composed of patch antennas, microstrip line antennas, etc. and a plurality of phase shifters 2. The switching device 4 switches the amount of phase shift of the phase shifter 2, and by switching the amount of phase shift of the phase shifter 2, the antenna beam is alternately switched between a ground beam and a forward beam. . The transmitting/receiving device 3 receives output from a phased array antenna that receives reflected waves from the ground, a moving object, an obstacle, etc. When the antenna is a ground beam, the speed of the moving object is measured, and when the antenna is a forward beam, the moving object is moving. The distance and relative speed between bodies or between a moving body and an obstacle are obtained by calculating data.

Therefore, the amount of phase shift of the phase shifter 2 is switched by the switching device 4, so that the beam of the antenna is directed alternately downward (ground beam) and in front (front beam).
The transmitter/receiver 3 can obtain data such as the speed of the moving objects and the distance and relative speed between the moving objects or between the moving objects and an obstacle using the transmitted and received signals obtained from each beam.

[Example 2] FIG. 2 shows Example 2. In the system configuration of Example 1, the data obtained by the transmitting/receiving device 3 is averaged by a plurality of continuous data in the arithmetic device 5, and the data is calculated as much as possible. We are trying to obtain accurate data. Therefore, by averaging a plurality of consecutive speed data using the arithmetic unit 5, the influence of road surfaces such as potholes and steps can be removed.

[Example 3] Example 3 is shown in FIG. In this embodiment, the transmitting/receiving device 3
Before the data obtained is averaged by the arithmetic unit 5, the data judgment device 6 removes abnormal data, etc., in which the amount of change in the data exceeds a certain value. Therefore,
In this data judgment device 6, when abnormal data that is considered to be caused by scattered waves etc. appears, abnormal data, etc. whose amount of change in data exceeds a certain value is removed, and then a plurality of continuous data are processed in the arithmetic device 5. Since the data are averaged, more accurate data can be obtained.

[Embodiment 4] FIG. 4 shows Embodiment 4, in which the antenna beam control bag W controls the switching device 4 to vary the phase shift amount of the phase shifter 2.
7. This antenna beam control device 7
, the switching device 4 is controlled to switch the phase shift amount of the phase shifter 2 to multiple stages, and the ground angle (θ,
, θ2. ...... A plurality of ground beams with different angles (θn) are formed, and the data obtained from the transmitting/receiving device 3 according to each beam is averaged by the arithmetic device 5 to calculate the speed of the moving object, etc. as much as possible. We are trying to obtain accurate data.

[Embodiment 5] FIG. 5 shows Embodiment 5. In this embodiment, in the system configuration of Embodiment 4, data obtained by the transmitting/receiving device t3 is
Abnormal data is removed by the data judgment device 6 before averaging by the arithmetic device 5. Since the abnormal data is removed and then averaged, even more accurate data can be obtained. It is.

[Effects of the Invention] As described above, the present invention provides a phased array antenna including a plurality of antenna elements and a plurality of phase shifters mounted on a moving object such as a vehicle, and an output of the phased array antenna that receives reflected waves. The transmitting/receiving device detects the speed of moving objects, the distance between moving objects, the distance between moving objects and obstacles, etc., and the phase shift amount of the phase shifter is switched to control the angle of the beam from the antenna element. Since the antenna is equipped with a switching device, the amount of phase shift of the phase shifter is switched by the switching device, so that the beam of the antenna is directed alternately in two directions, downward and forward, so that the gain can be obtained with each beam. The transmitter/receiver can obtain data such as the speed of the moving object and the distance and relative speed between the moving objects or between the moving object and the obstacle using the transmitted and received signals.
This provides the effect that the speed of a moving object and the distance and relative speed between moving objects or between a moving object and an obstacle can be obtained simultaneously and easily using one antenna system.

In addition, since it is equipped with an arithmetic device that averages a plurality of pieces of speed data, etc. output from the above-mentioned transmitting/receiving device and detects the speed, etc. of a moving object, the arithmetic device is used to calculate a plurality of consecutive speed data, etc. By averaging, it is possible to remove the effects of road surfaces such as potholes and steps.

Furthermore, as a means of averaging speed data etc. by the above-mentioned arithmetic unit, a data discrimination device is provided to remove abnormal data, so that when abnormal data that is thought to be caused by scattered waves etc. appears, Data that changes by more than the value is filtered by a data judgment device and then averaged to obtain the most accurate speed data, etc. even if there is an influence from scattered waves, etc. be able to.

Further, as a means for detecting the speed of the moving body of the transmitting/receiving device, an antenna beam control device is provided which shapes a plurality of antenna beams having different ground angles obtained by switching the phase shift amount of the phase shifter in multiple stages using the switching device. Since the arithmetic unit averages multiple pieces of speed data with different ground angles, the switching device and antenna beam control device switch the phase shift amount of the phase shifter into multiple stages to calculate each ground speed. Velocity data obtained from a plurality of different antenna beams can be similarly averaged to obtain highly accurate velocity data.

[Brief explanation of drawings]

FIG. 1 is a system configuration diagram of the first embodiment of the present invention, FIG. 2 is a system configuration diagram of the second embodiment of the above, FIG. 3 is a system configuration diagram of the third embodiment of the same, and FIG. 4 is an implementation of the same. FIG. 5 is a system configuration diagram of Example 4, and FIG. 5 is a system configuration diagram of Example 5. 1 is an antenna element, 2 is a sleeper, 3 is a transmitting/receiving device, 4 is a switching device, 5 is an arithmetic device, 6 is a data determination device, and 7 is an antenna beam control device.

Claims (4)

[Claims] (1) A phased array antenna consisting of multiple antenna elements and multiple phase shifters mounted on a moving object such as a vehicle, and the output of this phased array antenna that receives reflected waves, are used to control the speed of the moving object and the distance between the moving objects. and a switching device that switches the phase shift amount of the phase shifter to switch and control the angle of the beam from the antenna element. An in-vehicle radar system. (2) The in-vehicle radar system according to claim 1, further comprising an arithmetic device that averages a plurality of pieces of speed data outputted from the transmitting/receiving device to detect the speed, etc. of the moving body. (3) The in-vehicle radar system according to claim 2, further comprising a data determination device for removing abnormal data as means for averaging the speed data and the like by the arithmetic device. (4) An antenna beam control device that forms antenna beams with different ground angles obtained by switching the phase shift amount of the phase shifter in multiple stages using the switching device as a means for detecting the speed of the moving object of the transmitting/receiving device. 4. The in-vehicle radar system according to claim 2, wherein the arithmetic unit averages a plurality of speed data having different ground angles.