JP2002341020A - Signal processing method of scan type fm-cw radar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To specify the center of a target even when the target is a heavy vehicle to judge, in the reflection of two or more beams, whether they are reflected from the same target or not. SOLUTION: From peaks generated on the basis of radar signals reflected from the target, peaks having substantially the same peak frequency and a receiving level of a prescribed value or more are selected. When the number of selected peaks is 2, the angle of the peak present within a prescribed range angle from the maximum peak is determined, and the central angle between the angle of the peak and the angle of the maximum peak is set as the angle of the target. A pairing is performed for two or more peaks to detect the distance from each reflecting point of the target, relative speed and length of slippage, and when each of these differences between the both is a prescribed value or less, the peaks are judged to be the peaks of the same target.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a scanning FM-
The present invention relates to a method of processing reflected signals reflected from a plurality of locations when a large vehicle such as a truck is a target in a CW radar.

[0002]

2. Description of the Related Art In an inter-vehicle distance control, an on-vehicle radar device that emits a radar beam in front of a host vehicle and detects an object such as a preceding vehicle is used. As a radar device, there is an FM-CW radar using a radio wave such as a millimeter wave or a device using a laser beam. Using these radar devices, the distance to the preceding vehicle, the relative speed with respect to the preceding vehicle, and the accurate position of the preceding vehicle are detected, and the following distance control is performed.
In order to accurately detect the position of the preceding vehicle, it is important to detect the position of the approximate center of the preceding vehicle.

[0003]

However, if the target vehicle ahead is a large vehicle such as a truck,
Looking at the reception level of the signal reflected from the plurality of emitted beams, a plurality of peaks may appear. In such a case, it may be difficult to specify which peak represents the center of the target.

[0004] Similarly, when the target is a large vehicle, beams may be reflected from a plurality of portions of the same target but at different distances, and there is a risk that the targets may be erroneously recognized as different targets. Furthermore, when a large vehicle is traveling in an adjacent lane, the angle of the beam reflected from the vicinity of the mirror in front of the vehicle is close to the own lane, and may be mistaken as the preceding vehicle in the own vehicle lane.

[0005] When the target is a large vehicle, the beam is often reflected from a plurality of locations at the same target but at different distances. In such a case, using the distances, relative speeds, and angles obtained from these multiple locations,
It is necessary to obtain a representative value of the vehicle, that is, a distance to the vehicle, a relative speed, a width of the vehicle, a lateral position, and the like.

Further, when a beam is reflected from a plurality of locations of the same target but at different distances, in order to detect the distance and the relative speed to these different locations, the reflected signals of the respective locations are detected. Pairing of the peak frequency between the rising section and the falling section must be performed.

Accordingly, it is an object of the present invention to enable the center of a target to be accurately specified even in the case of a large vehicle.

Another object of the present invention is to determine whether or not a target such as a large vehicle whose beam is reflected from a plurality of places is a reflection from the same target. Another object of the present invention is to prevent a vehicle traveling in a lane adjacent to the front from being mistaken for a vehicle in the own vehicle lane.

Another object of the present invention is to make it possible to accurately obtain representative values of the distance to the target, the relative speed, the width, and the lateral position when the beam is reflected from a plurality of portions of the same target.

Another object of the present invention is to efficiently pair peak signals generated by beams reflected from a plurality of points on the same target. Another object is to effectively process target data obtained by pairing.

[0011]

According to the present invention, there is provided a signal processing method for a scanning type FM-CW radar, wherein a peak frequency of a peak generated based on a radar signal reflected from a target is determined. Are substantially the same and the reception level is equal to or greater than a predetermined value. If the number of the selected peaks is 2, the angle of the peak within a predetermined angle range from the maximum peak is obtained, and the angle of the peak and the maximum peak are determined. The angle of the center between the angles is obtained, and the obtained angle of the center is set as the angle of the target. In that case, the center angle is set as the target angle only when the difference between the reception level of the maximum peak and the peak at a predetermined angle from the maximum peak is equal to or less than a predetermined value, otherwise, the angle of the maximum peak is set as the target angle. And

When the number of peaks is three or more, the angles of these centers are determined from the angles of the leftmost and rightmost peaks, and the obtained center angle is used as the target angle.
In that case, only when the difference in the reception level between the maximum peak and the other peaks among the three or more peaks is equal to or less than a predetermined value,
The center angle is the target angle, otherwise the maximum peak angle is the target angle. Further, when the difference between the maximum peak and the reception level of the plurality of peaks among the other peaks is equal to or less than a predetermined value, the maximum peak and the plurality of peaks are determined from the angles of the leftmost and rightmost peaks. The angle of the center is determined, and the obtained angle of the center is set as the angle of the target.

According to the signal processing method of the scanning type FM-CW radar of the present invention, a plurality of peaks having substantially the same peak frequency are selected from the peaks generated based on the radar signal reflected from the target. Performing pairing on the plurality of peaks, detecting the distance from each reflection point of the target, the relative velocity, and the length of the deviation, and detecting the distance from each reflection point, the relative velocity, and the length of the deviation. Are smaller than a predetermined value, it is determined that the plurality of peaks are peaks of the same target. In this case, the angle of the peak from the reflection point with the shortest distance among the plurality of peaks is defined as the angle of the target. If the length of the deviation is larger than a predetermined value, it is determined that the target is traveling on an adjacent lane. When it is determined that the target is traveling on an adjacent lane while traveling on a curve, the target is corrected so that the position of the target is located at the center of the lane.

According to the signal processing method of the scanning FM-CW radar of the present invention, when it is determined that a plurality of peaks are generated based on a radar signal reflected from the same target, the plurality of peaks are determined. The minimum distance among the distances from the peak to the target is adopted as a representative value of the distance to the target.

Further, a relative speed with respect to the target is obtained from each of the plurality of peaks, and an average value of the obtained plurality of relative speeds is set as a representative value of the relative speed.

Further, the width of the target is determined from the peaks appearing at both ends, and this is used as a representative value of the width of the target. Then, the midpoint of the representative width is set as the representative value of the lateral position of the target.

If it is determined that a plurality of peaks are generated based on radar signals reflected from the same target, only the nearest reflection point and the peak due to the radar signal reflected from the point are selected. The width of the target is determined from the peaks appearing at both ends of the selected peak, and this is used as a representative value of the target width.

Further, according to the signal processing method of the scanning type FM-CW radar of the present invention, the reception level becomes maximum in the rising section and the falling section of the radar signal among the peaks generated based on the radar signal reflected from the target. Is extracted and paired, and then a peak signal having the same angle and frequency difference from the peak signal having the highest reception level is extracted from the rising section and the falling section to perform pairing.

A range R1 defined by a frequency and an angle having a predetermined width including the frequency and the angle of the maximum signal;
A range R2 wider than the range R1 is defined, and peaks having substantially the same angle are defined as ranges R1 of the ascending section and the descending section, respectively.
And from R2, perform pairing when the difference between the peak frequencies is within the predetermined range when searching from the range R1, and perform the pairing when the difference from the peak frequency is smaller than the predetermined range when searching from the range R2. Perform pairing if it is within the range.

Further, according to the signal processing method of the scanning type FM-CW radar of the present invention, it is determined whether or not the target obtained by pairing is a continuous target. If the target is not a continuous target, the data is not updated.

If the target obtained by pairing is not a continuous target, the data of the target is temporarily stored in a separately provided memory.

If the target obtained by the pairing is not a continuous target, it is determined whether the reflected power of the target detected this time is larger than the reflected power of the existing target, and the reflected power of the target detected this time is determined. Is greater than the reflected power of the existing target,
Update the data using the data of this target as the data of the existing target.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing an outline of the configuration of an inter-vehicle distance control device using a scanning radar in which the method of the present invention is used. The radar sensor unit is an FM-CW radar, and includes a radar antenna 1, a scanning mechanism 2, and a signal processing circuit 3. The inter-vehicle distance control ECU 7 receives signals from the steering sensor 4, the yaw rate sensor 5, the vehicle speed sensor 6, and the signal processing circuit 3 of the radar sensor unit, and controls the alarm 8, the brake 9, the throttle 10, and the like. The inter-vehicle distance control ECU 7 also sends a signal to the signal processing circuit 3 of the radar sensor unit.

FIG. 2 shows the configuration of the signal processing circuit 3 of FIG. The signal processing circuit 3 includes a scanning angle control unit 1
1, a radar signal processing unit 12, and a control target recognition unit 13. The radar signal processing unit 12 performs FFT processing on the reflected signal from the radar antenna 1, detects a power spectrum, calculates the distance to the target and the relative speed, and transmits the data to the control target recognition unit 13. The control target recognizing unit 13 receives the distance from the target, the relative speed received from the radar signal processing unit 12, and the vehicle information obtained from the steering sensor 4, the yaw rate sensor 5, the vehicle speed sensor 6, etc. The scan angle is instructed to the scan angle control unit 11 on the basis of this, and the target to be controlled is determined and transmitted to the following distance control ECU. The scanning angle control unit 11 controls a scanning angle or the like when traveling on a curve in the case of a fixed radar, and controls a scanning scanning angle in the case of a scanning radar. The scanning mechanism 2 receives a control signal from the scanning control unit 11 and sequentially emits a beam at a predetermined angle to perform scanning.

The FM-CW radar outputs, for example, a frequency-modulated continuous transmission wave in the form of a triangular wave to determine the distance to a target vehicle ahead. That is, the transmission wave from the radar is reflected by the vehicle ahead, and a beat signal (radar signal) obtained by mixing the reception signal and the transmission signal of the reflected wave is obtained. This beat signal is subjected to fast Fourier transform to perform frequency analysis. The frequency-analyzed beat signal has a peak at which the power becomes large relative to the target. The frequency corresponding to this peak is called a peak frequency.
The peak frequency has information on the distance, and the peak frequency differs between the rising and falling of the triangular-shaped FM-CW wave due to the Doppler effect due to the relative speed with the vehicle ahead. Then, the distance and the relative speed to the vehicle ahead can be obtained from the peak frequencies at the time of ascent and descent. When there are a plurality of vehicles ahead, a pair of peak frequencies when ascending and descending are generated for each vehicle. Forming a pair of peak frequencies at the time of ascending and descending is called pairing.

FIG. 3 is a diagram for explaining the principle of the FM-CW radar when the relative speed with respect to the target is zero. The transmission wave is a triangular wave whose frequency changes as shown by the solid line in FIG. Transmission center frequency fo of transmission wave, FM
The modulation width is Δf, and the repetition period is Tm. This transmission wave is reflected by the target and received by the antenna, and becomes a reception wave indicated by a broken line in FIG. The round-trip time T with the target is T = 2r / C, where r is the distance to the target and C is the propagation speed of the radio wave.

This received wave causes a frequency shift (beat) with the transmission signal in accordance with the distance between the radar and the target.

The frequency component fb of the beat signal can be expressed by the following equation. Note that fr is a distance frequency. fb = fr = (4 ・ Δf / C ・ Tm) r On the other hand, FIG. 4 is a diagram for explaining the principle of the FM-CW radar when the relative speed with respect to the target is v. The frequency of the transmission wave changes as shown by the solid line in FIG. This transmission wave is reflected by the target and received by the antenna, and becomes a reception wave indicated by a broken line in FIG. This received wave causes a frequency shift (beat) with the transmission signal according to the distance between the radar and the target. In this case, since there is a relative velocity v between the target and the target, a Doppler shift occurs, and the beat frequency component fb can be expressed by the following equation. Note that fr is a distance frequency, and fd is a speed frequency.

Fb = fr ± fd = (4 · Δf / C · Tm)
r ± (2 · fo / C) v FIG. 5 shows an example of the configuration of the FM-CW radar. As shown in the figure, the modulation signal is added from the modulation signal generator 21 to the voltage control oscillator 22 to perform FM modulation, and the FM modulation wave is transmitted to the outside via the transmission antenna AT, and a part of the transmission signal is branched. Frequency converter 23 like a mixer
Add to On the other hand, a reflected signal reflected by a target such as a preceding vehicle is received via a receiving antenna AR, and is mixed with an output signal of a voltage controlled oscillator 22 by a frequency converter 23 to generate a beat signal. The beat signal is A / D-converted by an A / D converter 25 via a baseband filter 24, and subjected to signal processing by a fast Fourier transform or the like by a CPU 26 to obtain a distance and a relative speed.

[0030]

[Embodiment 1] As shown in FIG. 6, when the preceding vehicle B is a large vehicle such as a truck with respect to the own vehicle A, a plurality of beams are reflected from the preceding vehicle B. For example, when a beam is emitted at an angle θa-θg, a large reflective target such as a truck has a large reception level and a large reflection area, so that a peak generated based on a beam emitted at an angle θa-θg is received. The levels are as shown in FIG. In this case, since the distance to the target is almost the same, the peak frequency is almost the same. But,
As shown in FIG. 7, the distribution of the reception level of a large vehicle sometimes has two peaks (Pc, Pf). Usually, the angle at which the reception level reaches a peak is defined as the angle at which the target exists. However, as shown in the figure, when there are two peaks,
There is a risk of misidentifying that there are two targets.

Therefore, according to the present invention, peaks having substantially the same peak frequency and having a reception level of a predetermined value (threshold)
For the above reflected signal, another peak (Pf) within a predetermined angle range θx from the maximum peak (Pc) is also regarded as one target, and the angle of the center between the peaks is set as the target angle. Things. For example, as shown in FIG. 8, including the additional peak Pf equal to or greater than the threshold value Pth in the maximum peak Pc to a predetermined angular range θx regarded as one target, and the angle of the target central angle theta _o peaks Pc and Pf I do.

However, if the difference between the reception levels of the peaks is too large, the target may not be the same target, or another peak that is not the maximum peak of the same target may not be the main part of the target. Very unlikely to be the center of the target.
Therefore, in the present invention, the difference between the maximum peak and the reception level is equal to or smaller than a predetermined value, that is, only the peak having a small difference in the reception level from the maximum peak is set as the peak of the reflected signal from one target, and the center angle between the peaks is set as the target angle. Angle. Specifically, referring to FIG. 8, only when the difference between the reception level of the maximum peak Pc and another peak Pf is equal to or less than a predetermined value ΔP, that is, when Pc−Pf ≦ ΔP, the target is regarded as one target. Are collectively defined as the angle of the target.

On the other hand, if the difference between the reception level of the maximum peak Pc and the reception level of another peak Pf is larger than the predetermined value ΔP, it is not necessarily regarded as one target, and the angle of the maximum peak is set as the angle of the target.

Next, how to determine the predetermined angle range will be described with reference to FIG. In FIG. 9A, A is the own vehicle, and B is the preceding vehicle. Preceding vehicle B
If the distance to is r and the width of the preceding vehicle is 2a,
Assuming that the angle of the beam with respect to a position left and right a from the center of the preceding vehicle is ax, the following equation is established.

Tan θx = a / r Therefore, θx = tan ⁻¹ a / r, and the angle range changes according to the inter-vehicle distance. This is shown in a graph in FIG.

In the above, the case where there are two peaks has been described. However, when there are three or more peaks having substantially the same peak frequency and the reception level being equal to or more than a predetermined value, for example, as shown in FIG. If there are three, Pd and Pe, the angle of the center between the leftmost peak Pb and the rightmost peak Pe is taken as the target angle.

Further, as shown in FIG.
If the difference between b and another peak Pd and Pf is large and the difference is larger than a predetermined value, that is, if Pb−Pd> ΔP Pb−Pf> ΔP, the angle θb of Pb is set as the target angle.

When the difference between the reception level of the maximum peak Pb and one of the other peaks Pd or Pf is equal to or smaller than a predetermined value, the center angle between the leftmost peak Pb and the rightmost peak Pd or Pf is determined. The angle of the target. In addition, when there are a plurality of peaks and a difference of the reception level from the maximum peak is less than a predetermined value but not all peaks, among the maximum peak and some of the peaks, the leftmost and rightmost peaks The angle at the center of the angle is defined as the angle of the target.

[Embodiment 2] In the case of a large vehicle such as a truck, a beam is reflected from a plurality of places at different distances, and therefore a difference occurs in the frequency of a beat signal based on a reflected signal. Especially in the case of large vehicles such as trucks running in adjacent lanes, reflections from the vicinity of the mirror position in front of the vehicle may be erroneously recognized as preceding vehicles because the measurement angle is closer to the own lane, and vehicles such as inter-vehicle distance control etc. May affect control. Therefore, in such a case, the present invention uses the positional relationship between the reflection from the rear portion of the large vehicle and the reflection from near the position of the front mirror to determine that the large vehicle is traveling on the adjacent lane. Things.

FIG. 12 shows a case where a large vehicle B is traveling ahead of a lane adjacent to the lane on which the vehicle A is traveling on a straight road. In this case, a beam is emitted from the own vehicle A to the large vehicle B, one of which is reflected from a point P1 near a mirror of the target vehicle B, and the other is reflected from a rear point P2 of the vehicle B. Suppose. in this case,
Although the peak frequencies based on the beams reflected from P1 and P2 are different, they are almost the same because the distance is short. Therefore, a peak having substantially the same peak frequency is selected from each of the ascending section and the descending section, and a plurality of peaks at the time of ascending and descending are paired. Then, the distance from each of the points P1 and P2, the relative speed, and the length of the deviation are detected. The distance between the detected points P1 and P2 in the traveling direction of the vehicle A is represented by r1,
r2, the relative velocities of the points P1 and P2 with respect to the own vehicle A are denoted by v1 and v2, respectively, and the length of a perpendicular line drawn from the points P1 and P2 with respect to the line Ls extended along the traveling direction of the own vehicle A ( Hereinafter, "the length of the deviation" is referred to as l1,
l2. In the present invention, (1) the distance difference (r1−r2) is within a predetermined range, for example, within the range of the track length, that is, r1−r2 ≦ Δr, and (2) the relative speed The difference (v1−v2) is within a predetermined range, that is, v1−v2 ≦ ΔV (ΔV ≒ 0). (3) The difference (11−12) in the length of the perpendicular is within a predetermined range, for example, the width of the track. If they are within the range, ie, l1-l2 ≦ Δl, it is determined that these two peaks are reflections from the same target. Then, without outputting detection data from the farther point, for example, the peak of the reflected signal from P1, the angle of the beam at the other peak is used as the target position. In other words, the angle of the peak from the reflection point at the shortest distance is defined as the angle of the target. By doing so, the position of the target to be controlled can be specified.

On the other hand, it is unclear whether the vehicle B is running on the adjacent lane or the own vehicle lane only under the conditions (1) to (3). Therefore, (4) l
If the value of 1 or 12 is larger than a predetermined value (for example, the width of a lane), it is determined that the target is traveling on an adjacent lane.

Here, how to determine l1, l2 and r1, r2 will be described. The angle of the beam b1 to the point P1 of the vehicle B with respect to the traveling direction Ls of the own vehicle A is θ1, the distance to the point P1 is R1, and the angle of the beam b2 to the point P2 with respect to the traveling direction Ls of the own vehicle A is θ2. Assuming that the distance to P2 is R2, sin θ1 = 11 / R1, therefore, 11 = R1sin
θ1 sin θ2 = l2 / R2, therefore l2 = R2sin
θ2 Also, cos θ1 = r1 / R1, therefore, r1 = R1cos
θ1 cos θ2 = r2 / R2, therefore, r2 = R2cos
θ2.

FIG. 13 shows a case where a large vehicle B is traveling ahead of a lane adjacent to the lane on which the vehicle A is traveling on a curve. In the case of this figure, similarly to the case of FIG. 12, a beam is emitted from the own vehicle A to the large vehicle B.
It is assumed that one is reflected from a point P1 near the mirror of the vehicle B, which is the target, and the other is reflected from a point P2 at the rear of the vehicle B. In this case, the extension line Ls in the traveling direction of the vehicle A
The distances between points P1 and P2 in the directions are r1 and r2, respectively.
And the relative velocities of the points P1 and P2 with respect to the own vehicle A are v1 and v2, respectively, and the lengths of the perpendiculars drawn from the points P1 and P2 with respect to the line Ls extending along the traveling direction of the own vehicle A are respectively Let l1 and l2 be the lengths extending from the intersection with Ls to the line Lc where the vehicle travels along the curve along the curve, respectively x1 and x2. In the present invention, FIG.
As in the case shown by (1), the distance difference (r1-r2) is within a predetermined range,
That is, r1−r2 ≦ Δr, and (2) the relative speed difference (v1-v2) is within a predetermined range, that is, V1−V2 ≦ ΔV, and (3) the length of the perpendicular (“the deviation Length ") If the difference between (l1 + x1) and (l2 + x2) is within a predetermined range, that is, | (l1 + x1)-(l2 + x2) | ≦ ΔL, these two peaks are reflections from the same target. Judge. And P1 for P2
Is inside the curve, P1 is not cut and output, P2
Is output, and the angle of P2 is set as the target position to be controlled.

On the other hand, it is unclear whether the vehicle B is traveling on the adjacent lane or the own vehicle lane only under the conditions (1) to (3). Therefore, (4)
If the value of (l1 + x1) or (l2 + x2) is larger than a predetermined value (for example, the width of a lane), it is determined that the target is traveling on an adjacent lane.

Since the method for obtaining l1, l2 and r1, r2 has been described above, the method for obtaining x1, x2 will now be described with reference to FIG. The radius of curvature of the curvature of the road and R, the line extension of perpendicular line in the traveling direction of extension Ls from point P1 connecting the P _R and the vehicle A point of intersection with the circumferential line Lc of the radius R and the line Ls Assuming that the angle formed by the vehicle is θ, the vehicle A
Since DOO point distance of a line connecting the P _R is approximately equal to r1, the following equation holds.

Sin θ = (r1 / 2) / R = r1 / 2R On the other hand, sin θ = x1 / r1, x1 = r1 sin θ = r1 × r1 / 2R = r1 ² / 2R
≒ R1 ² / 2R (r1 ≒ R1) Similarly, x2 can be obtained.

FIG. 15 is a diagram showing a case where a large vehicle such as a truck is traveling ahead of the lane adjacent to the own vehicle.
(A) is a case where the vehicle is traveling on a straight road, and (b) is a case where the vehicle is traveling on a curve. When the vehicle is traveling on a curve as shown in (b), the vehicle tends to be closer to the inside of the lane as shown in the figure than in the case of traveling on a straight line as shown in FIG. is there. Therefore, in the present invention, when the target is a large vehicle or the like, the correction is performed so that the position of the target is located at the center of the lane on the curve. This correction corrects the angle θ indicating the position of the target, and the correction angle θ increases as the distance between the host vehicle A and the preceding vehicle B decreases.

FIG. 16 is a diagram showing how the correction is made. FIG. 16A shows the peak P of the reflected signal from the target.
Is corrected to the center of the lane by Δθ to obtain the position of P ′. Δθ is changed as shown in FIG. 16B according to the distance from the preceding vehicle. That is,
The correction angle Δθ decreases as the distance increases.

[Embodiment 3] Even if there is only one target, since the beam has a length and a width, a beam is often reflected from a plurality of different places. In particular, this tendency becomes stronger in a large vehicle. . FIG. 17 shows a case where a beam is emitted from the vehicle A to the vehicle B ahead, and different places Pa, Pb and Pc of the vehicle B are emitted.
Shows a case in which the beam is reflected by. In such a case, the representative value of the target, ie, the distance to this vehicle,
It is necessary to determine the relative speed, the width of the vehicle, the lateral position that is the center point of the vehicle, and the like.

According to the present invention, the representative value is determined as follows. As shown in FIG. 17, beams reflected from different portions Pa, Pb, and Pc of the same target, that is, peaks generated based on radar signals are signal-processed. Then, values such as the distance from the own vehicle, the relative speed, the lateral position of the target, the width of the target, and the like are obtained from the plurality of signals obtained from the plurality of peaks, and a representative value is obtained from the obtained plurality of values.

More specifically, a representative value is obtained as follows. Regarding the distance from the own vehicle, a minimum distance among a plurality of distances obtained from a plurality of radar signals is adopted as a representative value. In FIG. 17, the distance from Pa is adopted as a representative value. When performing inter-vehicle distance control, the distance from the vehicle ahead is important, and accurate inter-vehicle distance control can be performed by employing the minimum distance as a representative value.

As for the relative speed, an average value of a plurality of relative speeds obtained from a plurality of radar signals is adopted as a representative value. Although the relative velocities originally obtained from the same target are the same, there are some errors in the relative velocities. Therefore, by taking the average value, a value with little error can be obtained.

As for the horizontal width and the horizontal position of the target, that is, the center position, a representative value is obtained and employed as follows. FIG. 18 is an enlarged view of a vehicle B portion in FIG. The representative value of the target width is obtained as follows.
First, the angle of the peak from the left end Pb and the right end Pc is determined. In other words, peaks are formed by the beams reflected from Pa, Pb, and Pc, respectively. The angles of the peaks located at both ends of these peaks are obtained, and the width Wbc is obtained from the angles. That is, the width of the target is determined from the interval between the peaks at both ends, and this is adopted as a representative value. Also, regarding the lateral position of the target, that is, the center position,
The angle of the middle point Pbc of the interval Wbc between the peaks at both ends is defined as a lateral position which is the center position in the width direction of the preceding vehicle.

However, when the representative value is obtained as described above, an accurate value may not always be obtained. In the present invention, the following method is employed in order to more accurately obtain the representative value. FIG. 19 is a diagram for explaining such a case. FIG. 19 is also an enlarged view of the portion of the vehicle B in FIG. When the center angle of the preceding vehicle B, that is, the center point in the width direction is obtained, the width W of the left end Pb and the right end Pc is calculated by the above-described method.
bc is set as the width of the target, and the angle of the intermediate point Pbc is set as the center point in the width direction of the preceding vehicle. However, as can be seen from FIG. 19, more precisely, the width Wab between Pb and Pa is the width of the target, and the midpoint Pab of the width Wab is the vehicle B ahead.
Is the center point in the width direction. Therefore, in order to obtain a more accurate value in the present invention, when a plurality of peaks are determined to be peaks from the same target, the beam reflected from the nearest reflection point and a point within a predetermined range from the point, that is, The representative value is determined using the peak generated from the radar signal.

In FIG. 19, the beam reflection point is Pa
, Pb, and Pc, the representative value is determined using the nearest reflection point Pa and the peak generated from the beam reflected from the point Pb within a predetermined range from the nearest reflection point Pa. Here, “within a predetermined range” means a dotted line d.
As shown by l, it is a predetermined distance from the closest reflection point Pa, and this distance is preferably equal to or less than the assumed maximum width of the detection target vehicle, and can be, for example, 5 m from Pa. Also, of the beams reflected from a point within an interval Δrp from the nearest reflection point Pa to the farthest reflection point Pc as a predetermined range, the closest reflection point P
A representative value is determined by using a peak generated by a beam reflected from a point in a range of a predetermined ratio from a, for example, 40%.

When the representative value is determined as described above,
The width of the front vehicle B, which is the target, is the distance Wab between the reflection points Pa and Pb, and the center position of this target is P
ab. Further, the distance between the own vehicle and the intermediate position Rab between the reflection points Pa and Pb can be obtained as the distance from the own vehicle. By obtaining the representative values of the lateral width and lateral position of the target as described above, more accurate values can be obtained.

In the above embodiment, the case where the number of reflection points of the beam is three is shown. However, the representative value can be determined in the same manner when the beam is reflected from four or five points. In that case, the number of peaks used to determine the representative value is Pa
, Pb may be three or more instead of two.

[Embodiment 4] The FM-CW radar outputs a triangular frequency-modulated continuous transmission wave to determine the distance to a target vehicle ahead. That is, the transmission wave from the radar is reflected by the vehicle ahead, and a beat signal (radar signal) between the reception signal and the transmission signal of the reflected wave is obtained. The beat signal is subjected to fast Fourier transform to perform frequency analysis. The frequency-analyzed beat signal has a peak at which the power becomes large relative to the target. A frequency corresponding to this peak is called a peak frequency. The peak frequency has information on the distance, and because of the Doppler effect due to the relative speed with respect to the preceding vehicle, the FM-CW having the triangular wave shape is used.
This peak frequency is different when the wave rises and when the wave falls.
Then, the distance and the relative speed with respect to the vehicle ahead can be obtained from the peak frequencies at the time of ascent and descent. Also, when there are a plurality of vehicles ahead, a pair of peak frequencies at the time of ascending and at the time of descending are generated for each vehicle. Forming a pair of peak frequencies at the time of ascending and descending is called pairing.

A plurality of beams are reflected from a large vehicle such as a truck, and even the same vehicle has different distances to the reflection point as shown in FIGS. Therefore, the signals in the ascending section and the descending section must be paired based on the beam reflected from the same reflection point, and the distance and the relative speed must be detected for each reflection point. Therefore, in the present invention, how to perform pairing will be described with reference to FIG. FIG. 20 is a graph in which the horizontal axis represents the angle of the peak of the signal reflected from the target, and the vertical axis represents the peak frequency. (1) First, of signals generated based on the beam reflected from the same target, a signal (Pmax) having the highest reception level in an ascending section and a descending section is extracted and paired. That is, the signal Pu-max of the maximum level among the signals in the rising section shown in FIG.
As shown in FIG. 0 (b), the signal Pd-max at the maximum level in the falling section is extracted. Then, Pu-max and Pd-max are paired. (2) Next, a peak signal in which the difference between the angle and the frequency from Pmax is substantially the same is extracted from the rising section and the falling section. For example, a vector from Pu-max to the peak P _C and α in rising section, Pd in falling section
The vector to peak P _F When a from -max, alpha ≒ a
If so, P _C and P _F perform pairing as a signal based on the beam reflected from the same point. (3) For P _D and P _G , if β ≒ b, P _D and P _G are paired as a signal based on the beam reflected from the same point. (4) For P _E and P _H , since γ ≠ c, pairing by this method is not performed, and normal pairing processing is performed.

Next, in the pairing process described with reference to FIG. 20, a more accurate pairing process will be described.
This will be described with reference to the graph of FIG. 21 and the flowchart of FIG.

In FIG. 21, the horizontal axis is the angle, and the vertical axis is the frequency. Then, the signal Pu-max of the maximum level among the signals in the ascending section shown in (a) and the signal Pd-max of the maximum level in the descending section shown in (b) are extracted and paired.

In FIG. 21, a range R1 and a range R2 wider than R1 are defined based on Pu-max and Pd-max. First, whether or not a peak exists in the range R1 in the rising section is searched. If the peak frequency f _up1
And the angle theta _up1 determined (S1), which is plotted as P _C as shown in FIG. 21 (a).

The ranges R1 and R2 are defined as appropriate.

[0064] Then in the range R1 of the falling section, to determine whether a peak having approximately the same angle as P _C is present (S
2), if present (Yes) frequency f of the peak P _{F
Find dw1} . Then, it is determined whether the difference between f _up1 and f _dw1 is in the following range (S3).

ΔF−x ≦ | f _up1 −f _dw1 | ≦ ΔF + x In the above equation, ΔF is the difference between the frequencies of Pu-max and Pd-max, and x is a preset value. This equation is f _up1 and f _dw1
Is larger than the difference between the frequencies of Pu-max and Pd-max. That is, when the peaks present in the range R1 is because it can be the difference between f _{Stay up-1} and f _dw1 taking slightly wider than ΔF to the correct pairing, the value of x in the above formula Is appropriately set within a range where accurate pairing can be performed.

[0066] Then, the conditions shown in the above equation if satisfied (Yes), to pair P _C and P _F (S4).

Next, the case of No in S2 or S3, searches whether a peak other than the search range R1 in the range R2 of rising section peaks are present, if present frequency f _up2
And the angle theta _up2 determined (S5), which is plotted as P _D as shown in FIG. 21 (a).

Next, it is determined whether a peak having approximately the same angle in the range R2 and P _D of falling portion is present (S
6) If present (Yes), the frequency f of the peak P _{G
Find dw2} . The difference between f _up2 and f _dw2 it is determined whether the range of the following (S7).

[0069] _{ΔF-y ≦ | f up2 -f} dw2 | ≦ ΔF + y y is a value set in advance as with x. But,
In this case, since the peaks existing in the range R2 wider than the range R1 are combined and paired, the conditions are stricter than in the case where the peaks in the range R1 are combined, and y <x
And This makes it possible to avoid erroneous pairing even when peaks existing in a wide range R2 are combined.

If the condition shown by the above equation is satisfied (Yes), P _D and P _G are paired (S8).

In the case of No in S6 or S7, the process ends without performing pairing.

In the above description of the embodiment, the case where a large vehicle is the target has been described. However, the appearance of a plurality of peaks in the reception level is not necessarily limited to a large vehicle. In addition, it is not always large that the beam is reflected from a plurality of places where the distance of the same target is different. Therefore, in the present invention, the target is not limited to a large vehicle.

Embodiment 5 FIGS. 23, 24 and 25 show
5 is a flowchart illustrating a method of processing target data obtained by pairing. For example, S4 in FIG.
Alternatively, a method of processing data obtained by pairing according to whether data obtained by pairing in S8 is a continuous target, that is, a target detected and paired in the previous or previous cycle is shown. It is a thing.

In FIG. 23, it is determined whether or not the target obtained by pairing in S4 or S8 is a continuous target (S9). If it is a continuous target (Ye
s), data such as distance and relative speed are updated (S1).
0). If the target is not a continuous target (No), the process ends without updating data such as the distance and the relative speed.

In the flowchart of FIG. 24, FIG.
If it is determined in S9 of the flowchart of No. 3 that the target is not a continuous target (No), the data of the paired target is temporarily stored in a separately provided memory (S11). Even if the data is not determined to be a continuous target, if data that is continuous with the temporarily stored data appears in the next cycle, it can be treated as a new target. In the present invention, the paired data is temporarily stored in preparation for such a case.

In S9 of the flowchart in FIG.
When it is determined that the target is not a continuous target (No), it is determined whether or not the reflected power of the target detected this time is higher than the reflected power of the existing target (S1).
2). As a result, if the reflected power of the target detected this time is higher than the reflected power of the existing target, the data of the current target is set as the data of the existing target (S13), and the data is updated (S10). FIG.
The method shown in the flowchart of the above, when the reflected power from the dispersed existing target is united into one, it may not be determined as a continuous target, so the reflected power is compared in this way, When the reflection power is higher than that of the existing target, the data is updated. In S12, when it is determined that the reflection power of the target detected this time is not higher than the reflection power of the existing target (No), as shown in the flowchart of FIG. 24, this data is temporarily stored in a separately provided memory. It can also be done (S11).

[Embodiment 6] FIGS. 26 and 27 are examples of flowcharts showing the method of the present invention described in Embodiments 1 to 4. In the flowchart of the figure, control and determination in each step are performed by the signal processing circuit 3 in FIG.

First, peaks having almost the same frequency are grouped in S1. When the targets are at the same distance from the own vehicle, the peak frequencies are almost the same. For example, in the case of a large vehicle, beams are reflected from a plurality of locations at different distances, and a plurality of peaks are generated. Therefore, peaks having substantially the same peak frequency are grouped.

Next, in S2, it is determined whether the reception level of the grouped peaks is equal to or higher than a predetermined value (threshold). This is because a large vehicle has a higher detected peak level. S
If Yes in 2, it is determined whether or not the detection angle of the peak having substantially the same frequency is within a predetermined range (S3). This is determined, for example, by determining whether the range of the detection angle between the peaks at both ends of the grouped peaks is a predetermined range. If Yes in S3, the process proceeds to S4, and it is determined whether or not the difference between the reception levels of these peaks is within a predetermined value (threshold). This is because peaks having little difference in reception level are put together. Y in S4
If es, regrouping processing is performed. That is, the peaks of the same target are put together (S5).

Next, it is determined whether or not the difference between the reception levels of the peaks regrouped and collected is small (S
6). In this case, the difference between the reception levels is set to a value smaller than the difference set in S4. The difference between the peak reception levels is small,
At approximately the same level (Yes), multiple beams are likely to be reflected at the same intensity from the same target, for example, the back of a heavy truck or bus, so the leftmost of the regrouped peaks The angle of the center between the peak angle of the peak and the rightmost peak angle is set as the target angle (S7). On the other hand, when the difference between the reception levels of the regrouped and combined peaks is large, for example, when there is one large peak and small peaks are present on both sides, the angle of the largest peak, which is the large peak, is set to the target angle. The angle is set (S8).

On the other hand, in the case of No in S2, S3, S4, that is, the reception level is not more than the predetermined value, the detection angle of the peak having substantially the same peak frequency is not within a certain range, or the difference between the reception levels is different. Is not within the specified value,
These peaks can be from different targets, or from the same target but at different distances,
For example, there may be peaks from the front mirror portion and the vicinity of the rear taillight. Therefore, these peaks do not undergo the regrouping process and proceed to S9.

Next, in S9, the peak frequencies at the time of ascending and descending are paired with respect to the plurality of regrouped peaks or the plurality of peaks grouped at S1, and a plurality of beams are reflected at S10. The distance to each part of the target, the relative speed, the detection angle, and the length of the lateral displacement from the lane in which the vehicle is running are determined. The pairing is performed, for example, as described in the above [Embodiment 4]. Further, the length of the deviation is obtained as described in the above [Example 2]. Then, in S11, a process of taking over past data is performed to maintain continuity of target data.

Next, in S12, the difference between the distance, the relative speed obtained for each part, and the length of the lateral displacement from the lane in which the vehicle is running is determined by a predetermined value (threshold: Δr, Δr).
v, Δl). If the difference in the distance, relative speed, angle, and deviation from the lane to the lateral direction of each part of the target obtained based on each peak in S12 is within a predetermined value range (Yes), these peaks are the same target. Therefore, a determination is made that the vehicle is a large vehicle. That is, +
Count 1 (S13). This counting is performed for each flow. Then, it is determined in S14 whether or not the large vehicle determination count is equal to or greater than a predetermined value.
This means that the requirement to be determined as a large vehicle in S12,
Despite not being a large vehicle, for example, a case may be considered where a plurality of peaks from two vehicles traveling in front in parallel happen to satisfy the above requirements, and a single determination does not necessarily mean a large vehicle. This is because it cannot be determined. S14
If the count is equal to or greater than the predetermined value (Yes), it is determined that the vehicle is a large vehicle (S15). However, if the count value is not equal to or greater than the predetermined value (No), the flow ends, and proceeds to the next flow.

Next, of a plurality of peaks determined to be a large vehicle, the output of the distance and relative speed determined from the peak based on the beam reflected from the far part such as the front part of the vehicle, for example, near the mirror position. Is excluded (S16). In other words, the angle of the peak from the closest reflection point is set as the target angle. Then, the position of the target obtained from the peak based on the beam reflected from the rear of the vehicle is set as the control target position. However, when it is determined that the position of the target is in the adjacent lane, the detection angle of the large vehicle is corrected so as to come outside as shown in FIG. 16 (S1).
7), end the flow. Whether the target is for an adjacent lane can be determined by the method described in [Embodiment 2].

On the other hand, if No in S12, that is,
Differences in distance, relative speed, angle of each part of the target obtained based on each peak, and deviations in the lateral direction from the lane are not within predetermined values, and differences in respective distances, relative speeds, etc. are predetermined. If it exceeds the value, the process proceeds to S18. Then, the predetermined range (threshold) is expanded and another threshold (Δ
r ′, Δv ′, Δl ′). If the result of determination in S18 is that the requirements are not satisfied again (No),
The large vehicle determination counter is set to -1 (S19). Next, it is determined whether or not the large vehicle determination counter is 0 (S20).
If es, the large vehicle determination is canceled (S21). If the requirement is satisfied in S18 (Yes) and if the counter is not 0 in S20 (No), the flow ends without canceling the large vehicle determination.

FIG. 28 is an example of a flowchart showing the method of the present invention described in the third embodiment. The flowchart of FIG. 28 corresponds to steps S13-S of the flowchart of FIG.
17 is replaced with steps S30 to S34.

In S30 of FIG. 28, when it is determined that a plurality of peaks are from the same target,
That is, in S12 of the flowchart of FIG.
If it is determined according to the present invention, the minimum distance among the distances obtained from each of the plurality of peaks is adopted as the representative value (S31). Next, an average value of relative velocities obtained from each of the plurality of peaks is obtained, and this is adopted as a representative value (S32). In addition, regarding the width of the target, the angles of the peaks appearing at both ends of the plurality of peaks are obtained, and the interval between both ends of the target is obtained from the angles,
This is adopted as a representative value of the target width (S3
3). Further, the angle of the intermediate point is obtained from the angles of the peaks at both ends, and is adopted as a representative value of the lateral position (S34).

FIG. 29 is also an example of a flowchart showing the method of the present invention described in the third embodiment. The flowchart of FIG. 29 corresponds to steps S33 and S33 of the flowchart of FIG.
34 is a modification.

S30, S31, and S32 in FIG.
The average value of the minimum distance and the relative speed is adopted as the representative value. On the other hand, in S40, only the peak due to the beam reflected from the nearest reflection point and a point within a predetermined range from the point is selected from the plurality of peaks (S40). And among the selected peaks
The angles of the peaks appearing at both ends are obtained, the distance between both ends of the target is obtained from the angles, and adopted as a representative value of the width of the target (S41).

[0090]

According to the present invention, even when a plurality of peaks due to the reflection signal are generated, it is possible to specify the approximate center position of the target. Also, even if multiple beams are reflected from different distances of the same target,
Since it can be determined whether or not the targets are the same, the vehicle can be controlled without mistaking the number of targets. In addition, it can be identified whether the target is traveling on the own vehicle lane or the adjacent lane.

Further, even when there are a plurality of peaks due to the beam reflected from the same target, it is possible to determine representative values of the distance, the relative speed, the lateral width, and the lateral position from these peaks, and perform accurate control.

[0092] Further, in the case of pairing signals by beams reflected from the same target at different distances from each other, it is possible to perform the pairing efficiently and accurately. Further, target data obtained by pairing can be effectively processed.

In addition, the effects described in the above embodiment can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a configuration of an inter-vehicle distance control device used in a method of the present invention.

FIG. 2 shows a configuration of a signal processing circuit 3 of FIG.

FIG. 3 is FM-C when the relative speed with the target is 0.
It is a figure for explaining the principle of W radar.

FIG. 4 is FM-C when the relative velocity with respect to the target is v.
It is a figure for explaining the principle of W radar.

FIG. 5 is a diagram illustrating an example of a configuration of an FM-CW radar.

FIG. 6 is a diagram showing a state of beam emission when the preceding vehicle is a large vehicle.

FIG. 7 shows a peak level due to a beam reflected from a heavy vehicle.

FIG. 8 is a diagram showing an example in which peaks due to beams reflected from a large vehicle are grouped in a specific angle range.

FIG. 9 is a diagram for explaining how to determine a specific angle range.

FIG. 10 is a diagram for explaining how to determine a target angle when there are three or more peaks.

FIG. 11 is a diagram for explaining how to determine a target angle when a difference between a maximum peak and another peak is large.

FIG. 12 shows a case where a large vehicle is traveling on an adjacent lane on a straight road.

FIG. 13 shows a case where a large vehicle is traveling on an adjacent lane on a curve.

FIG. 14 is a diagram for calculating how much a vehicle traveling on an adjacent lane on a curve is displaced laterally from a center line of the own lane.

FIG. 15 is a diagram showing a case where a large vehicle is traveling ahead of an adjacent lane.

FIG. 16 is a diagram showing how a position of a vehicle traveling on an adjacent lane is corrected.

FIG. 17 launches a beam from a vehicle A to a vehicle B ahead,
FIG. 7 is a diagram illustrating a case where a beam is reflected at a different portion of a vehicle B.

FIG. 18 is an enlarged view of a vehicle B portion of FIG.

19 is an enlarged view of a vehicle B portion in FIG.

FIG. 20 is a diagram for explaining a pairing method according to the present invention.

FIG. 21 is a diagram for explaining a pairing method according to the present invention.

FIG. 22 is a flowchart illustrating a pairing method according to the present invention.

FIG. 23 is a flowchart illustrating a method of processing target data obtained by pairing according to the present invention.

FIG. 24 is a flowchart illustrating a method of processing target data obtained by pairing according to the present invention.

FIG. 25 is a flowchart illustrating a method of processing target data obtained by pairing according to the present invention.

FIG. 26 is a flowchart showing an embodiment of the present invention.

FIG. 27 is a flowchart showing an embodiment of the present invention.

FIG. 28 is a flowchart showing a method of determining a representative value according to the present invention.

FIG. 29 is a flowchart showing a method of determining a representative value according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Radar antenna 2 ... Scanning mechanism 3 ... Signal processing circuit 4 ... Steering sensor 5 ... Yaw rate sensor 6 ... Vehicle speed sensor 7 ... Vehicle distance control ECU 8 ... Warning device 9 ... Brake 10 ... Throttle 11 ... Scanning angle control unit 12 ... Radar Signal processing unit 13 Control object recognition unit 21 Modulated signal generator 22 Voltage controlled oscillator 23 Frequency converter 24 Baseband filter 25 A / D converter 26 CPU A Own vehicle B Vehicle ahead

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F02D 29/02 301 F02D 29/02 301D G08G 1/16 G08G 1/16 E (72) Inventor Yasuhiro Sekiguchi Hyogo Hyogo 2-2-28, Goshodori, Hyogo-ku, Kobe, Japan Inside Fujitsu Ten Co., Ltd. (72) Inventor Daisaku Ongo 1-2-28, Goshodori, Hyogo-ku, Kobe, Hyogo F-term (reference) 3D044 AA01 AA25 AA31 AB01 AC26 AC31 AC56 AC59 AD04 AD21 AE03 AE04 AE05 3G093 AA01 BA23 CB09 CB11 DB05 DB16 DB18 DB21 EA09 EB04 FA02 5H180 AA02 CC12 CC14 LL04 LL06 LL09 LL15 5J070 AB19 AC01 AF01 AC01 AF02

Claims (23)

[Claims] 1. A signal processing method for a scanning type FM-CW radar, comprising: generating peaks having substantially the same peak frequency and having a reception level equal to or higher than a predetermined value among peaks generated based on a radar signal reflected from a target. When the number of selected peaks is 2, the angle of a peak within a predetermined angle range from the maximum peak is obtained, and the angle of the center between the angle of the peak and the angle of the maximum peak is obtained. Scan type FM with the angle of the center as the angle of the target
-Signal processing method of CW radar. 2. The scan according to claim 1, wherein the center angle is set as a target angle only when a difference between a reception level of the maximum peak and a peak at a predetermined angle from the maximum peak is equal to or smaller than a predetermined value. Expression FM-CW radar signal processing method. 3. The scan according to claim 1, wherein when a difference between a reception level of the maximum peak and a peak at a predetermined angle from the maximum peak is larger than a predetermined value, the angle of the maximum peak is set as a target angle. Expression FM-CW radar signal processing method. 4. A signal processing method for a scanning type FM-CW radar, wherein peaks having substantially the same peak frequency and having a reception level equal to or higher than a predetermined value among peaks generated based on a radar signal reflected from a target. If the number of the peaks is 3 or more, a scanning FM-CW radar in which the angles of these centers are determined from the angles of the leftmost and rightmost peaks and the obtained center angle is used as the target angle Signal processing method. 5. The target angle according to claim 4, wherein the center angle is set as the target angle only when the difference between the reception levels of the maximum peak and the other peaks among the three or more peaks is equal to or smaller than a predetermined value. A signal processing method for a scanning FM-CW radar. 6. The target angle according to claim 4, wherein the angle of the maximum peak is set as the target angle when the difference between the reception level of the maximum peak and the other peak among the three or more peaks is larger than a predetermined value. A signal processing method for a scanning FM-CW radar. 7. When the difference between the maximum peak and the plurality of other peaks among the three or more peaks is equal to or less than a predetermined value, the maximum peak and the plurality of peaks The scanning formula F according to claim 4, wherein the angles of these centers are obtained from the angles of the leftmost and rightmost peaks, and the obtained center angle is used as the target angle.
An M-CW radar signal processing method. 8. A signal processing method for a scanning FM-CW radar, comprising: selecting a plurality of peaks having substantially the same peak frequency among peaks generated based on a radar signal reflected from a target; Perform pairing for multiple peaks, detect the distance from each reflection point of the target, the relative velocity, and the length of the deviation, and detect the difference between the distance from each reflection point, the relative velocity, and the length of the deviation. Are smaller than a predetermined value, the plurality of peaks are determined to be peaks of the same target.
-Signal processing method of CW radar. 9. The signal processing method for a scanning FM-CW radar according to claim 8, wherein an angle of a peak from the reflection point having the closest distance among the plurality of peaks is set as a target angle. 10. The signal processing method for a scanning FM-CW radar according to claim 8, wherein the same target is determined to be a large vehicle. 11. The signal processing method for a scanning FM-CW radar according to claim 8, wherein if the length of the deviation is larger than a predetermined value, the target is determined to be traveling on an adjacent lane. 12. When the target is determined to be traveling on an adjacent lane while traveling on a curve, the position of the target is corrected to be at the center of the lane.
4. The signal processing method for a scan-type FM-CW radar according to item 1. 13. A signal processing method for a scanning FM-CW radar, wherein a peak having a maximum reception level in a rising section and a falling section of a radar signal among peaks generated based on a radar signal reflected from a target. A scanning type FM in which a signal is extracted and paired, and then a peak signal having the same angle and frequency difference from the peak signal having the highest reception level is extracted from the rising section and the falling section to perform pairing. -Signal processing method of CW radar. 14. A signal processing method for a scanning FM-CW radar, wherein, among peaks generated based on a radar signal reflected from a target, a reception level having a maximum in a rising section and a falling section of the radar signal. Each of the peak signals is extracted and paired, and a range R1 defined by a frequency and an angle having a predetermined width including a frequency and an angle of the maximum signal and a range R2 wider than the range R1 are defined, and have substantially the same angle. Peaks are searched from the ranges R1 and R2 of the ascending section and the descending section, respectively.
Pairing is performed when the difference between the peak frequencies is within a predetermined range when searching from 1, and the difference between the peak frequencies is within a predetermined range smaller than the predetermined range when searching from the range R2. A signal processing method for a scanning FM-CW radar that performs pairing in a case. 15. A signal processing method for a scanning FM-CW radar, wherein a peak having a maximum reception level in a rising section and a falling section of a radar signal among peaks generated based on a radar signal reflected from a target. Scanning FM-C which takes out signals, performs pairing, determines whether the target obtained by pairing is a continuous target, and does not update data unless the target is a continuous target.
W radar signal processing method. 16. The signal processing method for a scan-type FM-CW radar according to claim 15, wherein if the target obtained by the pairing is not a continuous target, data of the target is temporarily stored in a separately provided memory. . 17. If the target obtained by the pairing is not a continuous target, it is determined whether or not the reflected power of the target detected this time is higher than the reflected power of the existing target. 16. The signal processing method of the scanning FM-CW radar according to claim 15, wherein when the power is higher than the reflection power of the existing target, the data of the current target is updated as the data of the existing target. 18. The method according to claim 17, wherein when the reflection power of the target detected this time is not higher than the reflection power of the existing target, data of the target detected this time is temporarily stored in a separately provided memory. A signal processing method for a scanning FM-CW radar. 19. A signal processing method for a scanning FM-CW radar, wherein when it is determined that a plurality of peaks are generated based on a radar signal reflected from the same target, the plurality of peaks are determined. A signal processing method for a scanning FM-CW radar, wherein a minimum distance among the obtained distances to the target is adopted as a representative value of the distance to the target. 20. A signal processing method for a scanning FM-CW radar, wherein when it is determined that a plurality of peaks are generated based on a radar signal reflected from the same target, a relative velocity with respect to the target is determined. Is obtained from each of the plurality of peaks, and an average value of the obtained plurality of relative speeds is used as a representative value of the relative speed. 21. A signal processing method for a scanning FM-CW radar, wherein when it is determined that a plurality of peaks are generated based on radar signals reflected from the same target, peaks appearing at both ends. A signal processing method of a scanning type FM-CW radar, wherein a target width is obtained from the above, and this is used as a representative value of the target width. 22. The signal processing method for a scanning FM-CW radar according to claim 21, wherein an intermediate point of the representative width is set as a representative value of a lateral position of the target. 23. A signal processing method for a scanning FM-CW radar, wherein when it is determined that a plurality of peaks are generated based on a radar signal reflected from the same target, the nearest reflection point and Only the peak of the radar signal reflected from a point within a predetermined range from the point is selected, the width of the target is determined from the peaks appearing at both ends of the selected peak, and this is represented by a representative value of the target width. , A signal processing method of a scanning FM-CW radar.