KR20160081507A - Vehicle radar system - Google Patents

Abstract

The present invention relates to a vehicle radar system comprising: a transmitting/receiving module which radiates frequency modulated continuous wave (FMCW) signals, and receives a plurality of reflective signals returned when the FMCW signals are reflected from multiple targets; and a signal processing module which tracks the target according to a lot of target information extracted by processing the plurality of reflective signals. The signal processing module comprises: a signal processing unit which extracts the target information; a false target estimating unit which confirms whether or not at least one among the multiple targets is a false target based on the target information; and a target tracking unit which tracks a target which is not the false target among the multiple targets.

Description

[0001] The present invention relates to a vehicle radar system,

[0001] The present invention relates to a radar system for a vehicle, and more particularly to a radar system for a vehicle, which is capable of distinguishing a stationary target and a moving target for multiple targets by a reflection signal reflected by an FMCW signal, that is, a chirp signal, And more particularly to a radar system for a vehicle.

A radar is a device that can detect information such as distance, speed and angle of a target.

The electromagnetic wave signal is radiated through the transmission antenna of the radar, and a signal reflected from the target and returned is received from the reception antenna, and the information of the target can be obtained using the received signal.

Radar technology has been developed from the military and aeronautical fields, but has recently been applied to automobiles as a technology for warning and actively preventing and avoiding the risk of vehicle accidents. In automotive radar environments, it is difficult to find information on targets by unwanted continuous clutter signals such as tunnels, guard rails, and buildings.

In recent years, studies are underway to estimate false targets in moving targets in determining whether to stop and move targets on multiple targets based on the reflected signals received by the vehicle radar.

An object of the present invention is to provide a radar system for a vehicle which can distinguish a stationary target and a moving target for multiple targets from an FMCW signal, that is, a reflection signal reflected by a chirp signal, and to easily estimate a false target during a moving target .

A radar system for a vehicle according to the present invention includes a transmission / reception module that emits a Frequency Modulated Continuous Wave (FMCW) signal and receives a plurality of reflection signals that are reflected by the FMCW signal in multiple targets, And a signal processing module for tracking the target according to a plurality of target information extracted by the signal processing module, wherein the signal processing module includes: a signal processing unit for extracting the plurality of target information; A false target estimating unit for determining whether at least one of the targets is a false target, and a target tracking unit for tracking a target that is not the false target among the multiple targets.

The signal processing unit extracts the plurality of target information including the distance, speed, distance, and bit frequency of each of the multiple targets based on the FMCW signal and the plurality of reflection signals.

Wherein the false target estimating unit estimates whether the target is a stationary target or a moving target based on the velocity and the angle of each of the multiple targets and a target estimating unit estimating at least one of the multiple targets in the target estimating unit, And a false estimation unit for estimating a false target according to a bit frequency of each of the multiple targets.

The target estimator estimates the multiple target as a stop target if the velocity and the calculated angle are smaller than a set stop threshold value and estimates the multiple target as the target when the stop target value is greater than the stop threshold.

Wherein the target estimator estimates each of the multiple targets as the stationary target or the moving target according to V / cos θ <stop threshold, backward stop target, V / cos θ ≥ stop threshold, Where V is the velocity of the target and θ is the angle of the target.

Wherein the false estimation section determines that at least one bit frequency among the multiple targets is at least one bit frequency estimated as the stationary target among the multiple targets And estimates at least one of the multiple targets estimated as the moving target as a false target when the number of the FMCW signals is equal to or greater than 50% of the number of the FMCW signals.

The target tracking unit tracks the moving target excluding the false target estimated by the false estimation unit among the multiple targets.

The vehicular radar system according to the present invention has an advantage that the target detection capability can be improved by allowing the fake target to be estimated during multiple targets without increasing the number of FMCW signals, that is, chirp signals.

1 is a control block diagram showing a control configuration of a radar system for a vehicle according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

Hereinafter, embodiments will be described in detail with reference to the drawings.

1 is a control block diagram showing a control configuration of a radar system for a vehicle according to the present invention.

Referring to FIG. 1, a vehicle radar system may include a transmission / reception module 110 and a signal processing module 120.

The transmission / reception module 110 may include a transmission antenna 112, a plurality of reception antennas 114, and a driving module 116.

The transmission antenna 112 may continuously radiate an FMCW signal, that is, a chirp signal, whose frequency is changed linearly according to a chirp profile set from the signal processing module 120. [

The receiving antenna 114 can receive the reflected signal reflected by the multiple targets by the chirp signal radiated from the transmitting antenna 112.

At this time, the reflected signal is a signal in which a time delay is delayed by a distance from a multiple target, and a frequency shift is performed with respect to a state velocity of the multiple target, and the reception antenna 114 may include a plurality of reception antennas.

The driving module 116 converts the reflection signal received by the reception antenna 114 into a low frequency signal through a mixer and obtains a signal having a frequency difference component between the chirp signal and the reflection signal.

The driving module 116 then filters unwanted noise in the signal having the frequency difference component and can convert the analog signal into a digital signal.

The signal processing module 120 may include a signal processing unit 122, a false target estimating unit 124, and a target tracking unit 126.

The signal processing unit 122 may process the digital signal converted by the driving module 116 to extract target information including the distance, speed, angle, and bit frequency of each of the multiple targets.

That is, the signal processing unit 122 performs processing such as Window, Fast Fourier Transform (FFT), Digital Beam Forming (DBF), Constant False Alarm Ratio (CFAR), and distance-speed calculation.

The false target estimating unit 124 may include a target estimating unit 132 and a false estimation unit 134. [

The target estimating unit 132 may estimate whether each of the multiple targets is a stationary target or a moving target based on the target information of each of the multiple targets.

That is, if the velocity included in the target information and the value calculated by the angle are smaller than a set stop threshold value, the target estimating unit 132 estimates the multiple target as a stop target, and if the stop target value is greater than the stop threshold value, The target can be estimated as the moving target.

The target tracking unit 132 can estimate whether each of the multiple targets is the stationary target or the moving target according to the following Equations (1) and (2).

Where V is the velocity of the target and θ is the angle of the target.

That is, the target estimating unit 132 estimates the stop target if the value calculated by the velocity and angle of each of the multiple targets is smaller than the set stop threshold value, and calculates the target value by the velocity and angle of each of the multiple targets Is greater than or equal to the stop threshold value.

The false estimation unit 134 may estimate false targets for at least one target estimated by the moving target among the multiple targets in the target tracking unit 132. [

That is, the false estimation unit 134 determines that at least one bit frequency estimated by the moving target among the multiple targets is equal to at least one bit frequency estimated by the stationary target among the multiple targets, and the number of FMCW signals Or the same FMCW

 If the number of signals is more than 50% of the number of signals, at least one of the multiple targets estimated by the moving target may be estimated as the false target.

For example,

Target
number R (distance) / V (speed) / A (angle) Bit frequency of 1st FMCW signal Bit frequency of 2nd FMCW signal Bit frequency of 3rd FMCW signal Bit frequency of 4th FMCW signal One R (1) /
V (1) /
A (1) F (1, 1) F (1, 2) F (1, 3) F (1, 4) 2 R (2) /
V (2) /
A (2) F (2, 1) F (3, 2) F (2, 3) F (3, 4) 3 R (3) /
V (3) /
A (3) F (3, 1) F (3, 2) F (4, 3) F (1, 4) 4 R (4) /
V (4) /
A (4) F (3, 1) F (4, 2) F (3, 3) F (4, 4) 5 R (5) /
V (5) /
A (5) F (4, 1) F (2, 2) F (5, 3) F (2, 4)

The target estimating unit 132 uses the speed of each of the multiple targets calculated by the signal processing unit 122 for the multiple targets and the vehicle speed of the vehicle on the multiple targets as shown in Table 1 to calculate the stop target and the moving target .

In Table 1, it is assumed that target numbers 1, 2 and 4 are stationary targets and target numbers 3 and 5 are estimated as moving targets.

At this time, the false estimation unit 134 can know that the bit frequency of the target number 3 is overlapped with the target frequencies 1, 2 and 4 for the first to fourth FMCW signals, Target number 3 of target numbers 3 and 5 can be estimated as a false target.

As described above, the false estimation unit 134 can know that the bit frequency of the target number 5 overlaps the bit frequencies for the first through fourth FMCW signals once at the target numbers 1, 2, and 4, The target number 5 of the target numbers 3 and 5 can be estimated as a moving target.

The target tracking unit 126 may track the moving target except for the false target estimated by the false estimation unit 134 in the multiple target.

It is to be understood that the terms "comprises", "comprising", or "having" as used in the foregoing description mean that the constituent element can be implanted unless specifically stated to the contrary, But should be construed as further including other elements.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It should be understood that various modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention.

Claims (7)

A transmission / reception module that emits a Frequency Modulated Continuous Wave (FMCW) signal, and receives a plurality of reflection signals from which the FMCW signal is reflected and reflected by multiple targets; And
And a signal processing module for tracking the target according to a plurality of target information extracted by signal processing the plurality of reflection signals,
Wherein the signal processing module comprises:
A signal processing unit for extracting the plurality of target information;
A false target estimating unit that determines, based on the plurality of target information, whether at least one target among the multiple targets is a false target; And
And a target tracking unit for tracking a target that is not the false target among the multiple targets. The method according to claim 1,
The signal processing unit,
And extracts the plurality of target information including the distance, velocity, distance, and bit frequency of each of the multiple targets based on the FMCW signal and the plurality of reflected signals. 3. The method of claim 2,
The false target estimating unit estimates,
A target estimator for estimating whether the target is a stationary target or a moving target based on the speed and angle of each of the multiple targets; And
And a false estimation unit for estimating a false target according to a bit frequency of each of the multiple targets if at least one of the multiple targets is estimated as the moving target in the target estimating unit. The method of claim 3,
Wherein the target estimator comprises:
Estimates the multiple target as a stop target if the velocity and the calculated angle are smaller than the set stop threshold value and estimates the multiple target as the move target if the stop and target velocity are greater than the stop threshold. The method of claim 3,
Wherein the target estimator comprises:
A vehicle radar system for estimating each of the multiple targets as the stationary target or the moving target according to the following equation;
[Mathematical Expression]
V / cos? &Lt; stop threshold, back stop target,
V / cos?? Stop threshold, backward moving target,
Where V is the velocity of the target and θ is the angle of the target. 5. The method of claim 4,
The false estimation unit may include:
Wherein at least one bit frequency of the multiple targets is equal to at least one bit frequency estimated as the stationary target among the multiple targets when at least one of the multiple targets is determined as the mobile target in the target estimation unit, Signal is equal to or greater than 50% of the number of the FMCW signals, estimates at least one of the multiple targets estimated as the moving target as a false target. The method according to claim 6,
The target-
And tracking the moving target excluding the false target estimated by the false estimation unit among the multiple targets.

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