JPH1164502A - Obstruction detecting radar device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discriminate whether a reflecting object is a car traveling ahead or not by calculating the distance from a concerned vehicle to a road side structure according to the comparison result of the correction data of a beat signal with a threshold according to the road side structure. SOLUTION: A beat signal B from a transmitter-receiver part 1 is converted into a frequency cell within a signal, processing part 21 to form spectral data. Respective peak frequencies Pfu , Pfd of UP section and DOWN section are extracted from them and outputted to a target processing part 6. The target processing part 6 combines the frequencies Pfu , Pfd , and calculates the relative speed V and distance R between a concerned vehicle and a vehicle running ahead on the basis of the set of the frequencies. On the other hand, a road side structure judgment part 211 detects the frequency in which a correction level Ld generated from the DOWN section spectral data Dd exceeds a set threshold level TH, and outputs a judgment signal H. A road side structure range finding part 212 calculates the distance Re to a road side structure on the basis of the judgment signal H and the concerned vehicle speed Vw from a vehicle speed sensor. Thus, it can be precisely discriminated whether the target is the vehicle running ahead or not.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of transmitting an FM-CW wave (frequency modulation-continuous wave) from a running vehicle to a reflecting object ahead of the vehicle and receiving the reflected wave. An obstacle detection radar device that measures the distance and relative speed between the host vehicle and a reflective object based on a signal, and particularly corrects the measured spectrum data to determine whether the reflective object is a traveling target vehicle (preceding vehicle). The present invention relates to an obstacle detection radar device capable of reliably identifying (a continuous roadside structure).

[0002]

2. Description of the Related Art FIG. 17 is a block diagram showing a conventional radar system for detecting obstacles using FM-CW waves described on page 287 of "Radar Technology" (published by IEICE, edited by Takashi Yoshida). FIG.

In FIG. 17, reference numerals 1 and 2 denote a transmitting / receiving unit and a signal processing unit of an obstacle detection radar device mounted on a vehicle, and reference numeral 3 denotes a reflecting object (detection target) located in front of the vehicle.

The transmitting / receiving section 1 transmits a transmission wave W1 (radio wave) and receives a reflection wave (reception wave) W2 from the reflecting object 3,
A beat signal B is output by mixing the transmission wave W1 and the reception wave W2. Further, the signal processing unit 2 measures a relative speed V and a distance R with respect to the reflecting object 3 based on the beat signal B from the transmission / reception unit 1.

A transmitting unit in the transmitting / receiving unit 1 includes a modulation voltage generator 101 for generating a modulation voltage Vm and a voltage control oscillator (VC) for controlling the modulation voltage Vm to generate an FM-CW wave.
O: Voltage Control Oscilla
tor) (hereinafter referred to as VCO) 102 and FM-CW
The circulator 103 includes a circulator 103 for transmitting a wave, and a transmission antenna 104 for transmitting the FM-CW wave transmitted through the circulator 103 to the reflection object 3 as a transmission wave W1.

[0006] The circulator 103 outputs a local signal WL corresponding to the transmission wave W 1 to a receiving section in the transmitting / receiving section 1. A receiving unit in the transmitting / receiving unit 1 includes a receiving antenna 105 that receives a reflected wave from the reflecting object 3 as a received wave W2,
A mixer 106 that mixes the received wave W2 and the local signal WL and outputs a beat signal B.

The signal processing unit 2 includes an A / D converter 201 for converting the beat signal B into digital data, and a fast Fourier transform (FFT: Fast Fourier transform) of the digital data.
erTransform), and a calculation unit 203 that calculates a relative speed V and a distance R between the vehicle and the reflective object 3.
And

FIG. 18 is an explanatory diagram showing the time change of each frequency of a general transmission wave W1 (solid line) and reception wave W2 (dashed line), wherein the vertical axis represents frequency f and the horizontal axis represents time t. . In FIG. 18, τ is the received wave W with respect to the transmitted wave W1.
2, and Δf is the transmission bandwidth of the transmission wave W1.

The transmission wave W1 and the reception wave W2 have a frequency f
Rises with time t (hereinafter U
P section) and a slope signal section in which the frequency f decreases with time t (hereinafter, referred to as a DOWN section). In the UP section and the DOWN section, frequency fluctuations called up-chirp and down-chirp occur, respectively.

Fbup is the beat frequency of the up-chirp in the UP section. If the frequency due to the distance R to the reflecting object 3 is fr, and the frequency due to the relative speed V with respect to the reflecting object 3 is fv, the frequency of both is determined. It is represented by the difference (fr-fv). fbdown is the down-chirp beat frequency in the DOWN section, and is represented by the sum of the above-mentioned frequencies fr and fv (fr + fv).

Next, the operation of the conventional obstacle detection radar device shown in FIG. 17 will be described with reference to FIG. In FIG. 17, the VCO 102 in the transmitting / receiving unit 1
Modulation voltage V consisting of a triangular wave from modulation voltage generator 101
m, frequency-modulated FM at a predetermined repetition cycle
-Output a CW wave.

The circulator 103 radiates the FM-CW wave output from the VCO 102 as a transmission wave W1 from the transmission antenna 104 toward the reflecting object 3, and inputs the FM-CW wave to the mixer 106 as a local signal WL.

Since the frequency f of the transmission wave W1 transmitted from the transmission antenna 104 is frequency-modulated by the triangular modulation voltage Vm, as shown by a solid line in FIG. And a DOWN section that decreases with time t.

The transmission wave W1 is reflected by the front reflecting object 3 and received from the reception antenna 105 as a reception wave W2. Subsequently, the mixer 106 generates a beat signal B by mixing the received wave W2 and the local signal WL.

Beat signal B output from mixer 106
As shown in FIG. 18, in the UP section, the frequency fr due to the distance R to the reflecting object 3 and the frequency fv due to the relative speed V (Doppler frequency) of the reflecting object 3
Is obtained as information fbup (= fr−fv) of the difference from
In the DOWN section, information fbdo of the sum of each frequency
wn (= fr + fv).

Each frequency information fbup and fbdown obtained in the UP section and the DOWN section of the beat signal B
Is converted into digital data by the A / D converter 201 in the signal processing unit 2,
T processing is performed, and the result is converted into a frequency cell.

The arithmetic section 203 calculates the distance R from the own vehicle to the reflecting object 3 by calculating the data string converted on the frequency cell, and also calculates the relative speed V between the own vehicle and the reflecting object 3. Is calculated. UP section and DO
The frequency information fbup and fbdown obtained in each of the WN sections can be represented by the following equations (1) and (2).

Fbup = 4 · Δf · R / (Tm · c) −2fo · V / c (1) fbdown = 4 · Δfr · R / (Tm · c) + 2fo · V / c (2)

However, in equations (1) and (2),
Δf, R and V are the same as described above, Tm is the modulation period, c is the speed of light, fo is the center frequency of the transmission wave W1, λ
Is the transmission center wavelength. From the equations (1) and (2), the distance R and the relative speed V between the vehicle and the reflecting object 3 are obtained.
Can be obtained by the following equations (3) and (4).

R = (Tm · c / 8 · Δf) (fbup + fbdown) (3) V = (c / 4 · fo) (fbdown−fbup) (4)

However, in equations (3) and (4),
Δf, R, V, Tm, c and fo are the same as described above, and λ is the center wavelength of the transmission wave W1. Thus,
When the obstacle detection radar device of FIG. 17 is mounted on an automobile and travels, the distance R and the relative speed V to the reflective object 3 are measured.

However, actually, not only the preceding vehicle but also roadside structures such as guardrails and side walls are detected as the reflecting objects 3 in the transmission / reception unit 1, so that the roadside structures and the target object (the obstacle detection radar device) are detected. Vehicle running ahead of a vehicle equipped with)
There is a risk that the roadside structure will be mistaken for a target object.

Therefore, for example, Japanese Patent Laid-Open No. Hei 5-232214.
An obstacle detection radar device described in Japanese Unexamined Patent Publication (Kokai) No. H11-27983 has been proposed. In this conventional device, when the spread width of the frequency distribution of the beat signal B is equal to or more than a predetermined value, and the calculated relative speed V of the reflective object 3 substantially matches the own vehicle speed, the reflective object 3 By determining that the vehicle is a roadside structure, the roadside structure is distinguished from the target vehicle.

Hereinafter, the operation of another conventional apparatus described in Japanese Patent Application Laid-Open No. 5-232214 will be described with reference to the plan views and explanatory views of FIGS. FIG. 19 is a plan view showing a running state of the vehicle. In FIG. 19, a transmission wave W1 is irradiated onto a fan-shaped region in a plane.

Reference numeral 401 denotes a host vehicle equipped with an obstacle detection radar device (not shown), and 402 denotes a preceding vehicle running ahead of the host vehicle 401. FIG. 20 is an explanatory diagram showing received data (spectral data) from the preceding vehicle 402 received on the own vehicle 401 under the situation of FIG.
The vertical axis represents the signal level Aw of the received wave W2, and the horizontal axis represents the received wave W2.
Frequency fw.

In FIG. 20, spectrum data is obtained by transmitting a transmission wave W1 from the own vehicle 401 and receiving a reflected wave from the rear part of the preceding vehicle 402 on the own vehicle 401 as a reception wave W2. Δfw is the occupied bandwidth of the spectrum data.

FIG. 21 is a plan view showing a state in which the host vehicle 401 has entered the curved road 405.
Roadside structures such as guardrails and side walls arranged beside the road 05, and 406a are the roadside structures 40 due to the transmission wave W1.
6 is an irradiation part (see a thick line). FIG. 22 is an explanatory diagram showing reception data (spectral data) from the roadside structure 406a received on the host vehicle 401 under the situation of FIG.

Here, the preceding vehicle 40 is located in front of the host vehicle 401.
2 (FIG. 19) and the roadside structure 406a
When the occupied bandwidth Δfw of each spectrum data (FIGS. 20 and 22) is compared with the case where (FIG. 21) is present, the case of the reflection from the roadside structure 406a indicates that the preceding vehicle 4
It can be seen that the band is wider than in the case of reflection from 02.

Therefore, referring to the spectrum data (FIGS. 20 and 22) of the reception wave W2 from the reflection object 3 (preceding vehicle 402 or roadside structure 406), the occupied bandwidth Δfw
Are different from each other, if the occupied bandwidth Δfw has a bandwidth equal to or more than a predetermined value and the relative speed V is substantially equal to the own vehicle speed, it is determined that the roadside structure 406 is a guardrail or a side wall or the like. can do.

However, actually, the roadside structure 40
The signal level Aw of the spectrum data due to the reception wave W2 from No. 6 is not uniform, for example, as shown in FIG.
A plurality of spectrum peaks exist in the frequency band of the variation and the reception wave W2.

Hereinafter, the received wave W2 will be described with reference to FIG.
The reason why there are a plurality of peaks in the signal level Aw will be described. In FIG. 24, 502 is the roadside structure 40
6, a guardrail 503; a support for the guardrail 502 or a streetlight; and 504, a signboard or a sign behind the guardrail 502.

For example, the transmission wave W1 is transmitted to the guard rail 50
2, the support 5 of the guardrail 502
Since the portion 03 is cylindrical, the reflected wave from the column 503 always shows a high level regardless of the incident angle θ of the transmitted transmission wave W1.

Further, the incident angle θ of the transmission wave W1 is substantially perpendicular to the signboard or the sign 504 behind the guardrail 502, so that the reflected wave from the signboard or the sign 504 always shows a high level.

However, the support 503 and the signboard or sign 50
The level of the reflected wave of the portion of the guard rail 502 other than 4 changes depending on the incident angle θ of the transmitted transmission wave W1. For the above reasons, the signal level Aw of the spectrum data due to the reflected wave from the roadside structure 406 varies as shown in FIG.

Therefore, as shown in FIGS. 20 and 22, the frequency distribution of the spectrum data is different (preceding vehicle 4).
In the case of 02, it concentrates on a substantially constant area as shown in FIG. 20, while in the case of the roadside structure 406, for example, the guardrail 502, it continuously spreads as shown in FIG. According to the method of distinguishing the preceding vehicle 402 from the roadside structure 406, it is difficult to recognize when the spectrum data of the roadside structure 406 has a plurality of peaks as shown in FIG.

[0036]

As described above, the conventional obstacle detection radar apparatus recognizes the preceding vehicle 402 and the roadside structure 406 simply from the difference in the occupied bandwidth Δfw of the spectrum data of the received wave W2. Therefore, there is a problem that recognition becomes difficult when the spectrum data has a plurality of peaks.

The present invention has been made in order to solve the above-described problems. By correcting measured spectral data, it is possible to determine whether or not a reflecting object is a target vehicle (preceding vehicle) (continuous roadside). It is an object of the present invention to obtain an obstacle detection radar device capable of reliably identifying a structure.

[0038]

An obstacle detection radar device according to a first aspect of the present invention is mounted on an own vehicle and has an FM-
A modulating voltage generating means for generating a CW wave, a transmitting antenna for transmitting an FM-CW wave as a transmitting wave, a receiving antenna for receiving a transmitting wave reflected by a reflecting object as a receiving wave, In an obstacle detection radar device including a mixer that mixes received waves to generate a beat signal, and a signal processing unit that performs frequency analysis of the beat signal to measure a relative speed and a distance between the host vehicle and a reflecting object, The processing unit includes a roadside structure detecting unit for detecting the roadside structure, the roadside structure detecting unit corrects the spectrum data of the beat signal, and converts the corrected spectrum data to the roadside structure. A roadside structure determining unit that determines a roadside structure by comparing with a corresponding threshold level, and a distance from the vehicle to the roadside structure according to a determination result of the roadside structure determining unit. It is intended to include a roadside structure distance measuring unit for calculating a.

By performing the spectrum correction process in this manner, spectral data having a bandwidth due to reflection from continuous roadside structures such as guardrails and side walls is emphasized and extracted, and the level data is compared with a predetermined threshold level value. The roadside structure is detected based on the roadside structure.

In the obstacle detection radar device according to a second aspect of the present invention, in the first aspect, the road-side structure distance measuring unit calculates a distance to the road-side structure based on a spectrum frequency of the spectrum data. Things.

According to a third aspect of the present invention, there is provided an obstacle detecting radar device according to the second aspect, further comprising: own vehicle speed detecting means for detecting a speed of the own vehicle as an own vehicle speed; Including Doppler shift component calculation means for calculating the Doppler shift component based on the own vehicle speed, based on the spectral frequency obtained by one-sided chirp of the spectral data and the Doppler shift component of the own vehicle speed,
The distance to the roadside structure is calculated.

According to a fourth aspect of the present invention, there is provided an obstacle detection radar device according to any one of the first to third aspects, wherein the road-side structure detection unit includes a distance to the road-side structure and a distance to the road-side structure. The roadside structure information storage unit that stores the signal level of the spectrum data according to the present invention, and compares the past data and the current data stored in the roadside structure information storage unit to determine whether the front of the vehicle is on a curved road. And a curved road determination unit that determines whether the vehicle is in the road.

As described above, by comparing the stored data of the distance and the signal level of the roadside structure with the past data and the present data, when the distance to the roadside structure is reduced or the signal level is increased, It is possible to determine that the front of the own vehicle is on a curved road, and notify the driver that the front is on a curved road to call attention.

According to a fifth aspect of the present invention, there is provided an obstacle detecting radar apparatus according to any one of the first to fourth aspects, further comprising an antenna scanning means for scanning a receiving antenna, wherein the signal processing unit comprises: And a receiving wave level recognizing means for recognizing a change in the level of the receiving wave in association with the antenna scanning means for recognizing the direction of the roadside structure.

According to a sixth aspect of the present invention, in the obstacle detection radar device according to the fifth aspect, the antenna scanning means includes: a plurality of transmitting antennas and receiving antennas; and one transmitting antenna and one receiving antenna. A plurality of transmitting antennas and receiving antennas are provided corresponding to at least the front center and the left and right directions of the own vehicle.

According to a seventh aspect of the present invention, in the obstacle detection radar device according to the sixth aspect, the received wave level recognizing means includes an amplitude data on a roadside structure of a received wave obtained from the front of the vehicle. , Comparing the received wave obtained from the left and right ends of the vehicle with the amplitude data on the roadside structure,
It recognizes the level change of the received wave reflected from the roadside structure.

As described above, in addition to the spectrum data on the roadside structure of the front transmission / reception beam and the spectrum data on the roadside structure obtained when the transmission / reception beam is swung left and right by the antenna scanning means, the front side transmission beam is obtained. The direction of the roadside structure can be recognized.

Further, in the obstacle detection radar device according to claim 8 of the present invention, in claim 7, the reception wave level recognizing means includes a roadside structure information storage unit related to the roadside structure distance measuring unit, a roadside structure information storage unit, A roadside structure orientation determination unit associated with the structure information storage unit, the roadside structure information storage unit stores the distance to the roadside structure based on the spectrum data obtained from the plurality of receiving antennas, The signal level of the spectrum data by the structure is stored as amplitude data, and the roadside structure direction determination unit determines the direction of the roadside structure based on the distance to the roadside structure and the amplitude data stored in the roadside structure information storage unit. Is determined.

According to a ninth aspect of the present invention, in the obstacle detection radar device according to any one of the first to eighth aspects, the signal processing unit corresponds to a preceding vehicle located in front of the host vehicle. The vehicle includes a vehicle spectrum removing unit that removes the peak frequency from the spectrum data, and the spectrum correcting unit corrects the spectrum data that has passed through the vehicle spectrum removing unit.

As described above, by removing the vehicle spectrum data due to the reflection from the preceding vehicle, even if the preceding vehicle exists ahead of the own vehicle and the spectrum data of the preceding vehicle and the roadside structure are mixed, the vehicle spectrum data is mixed. The distance can be calculated by reliably recognizing the roadside structure without being affected by the above.

[0051]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the present invention.
02, 3, B, R, V, Vm, W1, W2 and WL are the same as described above.

In FIG. 1, reference numeral 21 denotes a signal processing unit for measuring a distance R and a relative speed V from the reflecting object 3 based on the beat signal B, and the A / D converters 201 and F described above.
In addition to FT processing section 202, UP section spectrum data storage section 204 for storing UP section spectrum data Du from FFT processing section 202, and DOW for storing DOWN section spectrum data Dd from FFT processing section 202.
An N-segment spectrum data storage unit 205.

The signal processing section 21 includes an UP section peak detection section 206 for detecting the UP section peak frequency Pfu from the UP section spectrum data Du, and a DOWN section peak frequency Pfd from the DOWN section spectrum data Dd.
, A DOWN section peak detecting section 207 for detecting the distance, a target processing section 6 for measuring a distance R and a relative speed V to a target object (preceding vehicle) based on the peak frequencies Pfu and Pfd, and a DOWN section spectrum data Dd. Roadside structure detecting section 7 for detecting the roadside structure 406 (see FIGS. 21 and 24).

The target processing section 6 includes a detection frequency cell combination section 208 for combining cells of the detection frequency fw based on the peak frequencies Pfu and Pfd, and an arithmetic processing section 209 for measuring the distance R and the relative speed V. .

The roadside structure detecting section 7 corrects the DOWN section spectrum data Dd to generate a correction level Ld, and sets the correction level Ld (corrected DOWN section spectrum data Dd) to a predetermined threshold level. Roadside structure determination unit 211 to compare with TH
Road-side structure distance measuring unit 212 that measures the distance Re to the road-side structure 406 based on the determination signal H from the road-side structure determining unit 211 and the speed information of the own vehicle, that is, the own vehicle speed Vw.
And

Next, the operation of the first embodiment of the present invention shown in FIG. 1 will be described. As described above, the transmission / reception unit 1
A beat signal B output from the
The data is converted into digital data by the / D converter 201, and then converted into frequency data by the FFT processing unit 202 to become spectrum data.

Among the spectrum data obtained by the FFT processing section 202, the UP section spectrum data Du is
Stored in the section spectrum data storage unit 204,
The N section spectrum data Dd is stored in the DOWN section spectrum data storage unit 205.

UP section peak detector 206 and DOW
The N section peak detection unit 207 includes an UP section and a DOWN section.
The UP section peak frequency Pfu and the DOWN section peak frequency Pfd are extracted from the spectrum data Du and Dd of the section. 206 and 20 for each peak detector
7, the respective peak frequencies Pfu and Pfd are
It is input to the detected frequency cell combination unit 208 in the target processing unit 6.

The detected frequency cell combination unit 208
Each peak frequency P obtained in P section and DOWN section
fu and Pfd are combined. The arithmetic processing unit 209 calculates the relative speed V and the distance R between the host vehicle and the preceding vehicle based on the frequency set obtained by the detection frequency cell combination unit 208.

On the other hand, the DOWN section spectrum data Dd in the DOWN section spectrum data storage section 205 is input to the spectrum correction section 210 in the roadside structure detection section 7. Accordingly, the spectrum correction unit 210 performs spectrum correction for detecting the roadside structure 406, and generates a correction level Ld.

The roadside structure judging section 211 includes a preset threshold level TH and a correction level Ld.
And the correction level Ld becomes equal to the threshold level T
A frequency bin exceeding H is detected as a spectrum frequency due to reflection from the roadside structure 406, and this is output as a determination signal H.

The determination signal H, that is, the spectrum frequency, obtained by the roadside structure determining unit 211 includes the distance to the roadside structure 406 and the velocity component. The road-side structure distance measuring unit 212 calculates the distance Re to the road-side structure 406 based on the determination signal H (spectral frequency) and the own vehicle speed Vw calculated from a vehicle speed pulse of a vehicle speed sensor (not shown). I do.

Next, the operation of the roadside structure detecting section 7 for recognizing the roadside structure 406 will be described with reference to FIGS. FIG. 2 is a plan view showing the state of the host vehicle 601 traveling on a curved road 405. In FIG. 2, 406 and 406a are the same as those described above.

The host vehicle 601 is equipped with an obstacle detection radar device according to the present invention (see FIG. 1), and has a radiation range of 6
The transmission wave W1 is transmitted to the area 02 in front. In FIG. 2, a continuous roadside structure 40 is provided on the roadside of the curved road 405.
6 It is assumed that there is a guardrail, for example, and the host vehicle 601 is traveling on a straight road before it is obtained on a curved road 405.

By radiating the transmission wave W1 from the obstacle detection radar device of the host vehicle 601, the roadside structure 406 is provided.
The reflected wave reflected from the irradiation part 406a (thick line part) of the (guard rail) is received by the obstacle detection radar device as a reception wave W2.

FIG. 3 is a block diagram showing spectrum data (bar graph) obtained by performing FFT processing on a received wave and its roadside structure detection processing function, in which Aw, fw and TH are the same as those described above.

In FIG. 3, reference numeral 606 denotes a roadside structure 406.
The spectrum data corresponds to the reflected wave from the (guardrail). The correction level Ld (see the solid line) corresponds to the correction level value of the cell of interest (described later) located at the center of the spectrum data 606 of the roadside structure 406. The threshold level TH is set to, for example, about three times the average noise level.

Reference numeral 607 denotes a moving window for some frequency bins among all the frequency bins.
The number of frequency bins included in 7 is a fixed value. Reference numeral 608 denotes a cell of interest located at the center of the moving window 607, and reference numerals 609 and 610 denote reference cells located on both sides of the cell of interest 608.

614 and 615 are adders for adding the signal levels of the reference cells 609 and 610, 616 is an adder for further adding the added values of the adders 614 and 615, and 617 is the total of the reference cells 609 and 610. A division unit for calculating an average level. Adders 614-616
And the division unit 617 calculates the correction level L of the cell of interest 608.
The spectrum correction unit 210 for obtaining d is configured.

Reference numeral 618 denotes a threshold level T for detecting the roadside structure 406 (guardrail, side wall, etc.).
This is a threshold level generation unit that generates H (a predetermined value set in advance). Threshold level TH
Is input to the roadside structure determination unit 211 that compares the threshold level TH with the correction level Ld of the cell of interest 608.

As is apparent from FIG. 3, the roadside structure 4
The spectrum data 606 according to 06 is observed as a data value in which the signal level Aw rises over a plurality of frequency bins.

The moving window 607 is located at the center cell 6 of interest.
08 and the remaining reference cells 6 on both sides of the cell of interest 608
09 and 610. Here, a case is shown where the number of frequency bins of the reference cells 609 and 610 is set to 8, and 17 frequency bins are set as the moving window 607.

Hereinafter, a method of calculating the correction level Ld of the cell of interest 608 will be described. First, the sum of the signal levels of the reference cells 609 on the left side of the cell of interest 608 in the moving window 607 is obtained by the adding unit 614, and the sum of the signal levels of the reference cells 610 on the right side of the cell of interest 608 is obtained by 615.

Subsequently, the adding section 616 causes each adding section 6
The sum of the addition results of 14 and 615 is obtained, and a division unit 617 performs 1 / N (N = 16) division.
The average level of the reference cells 609 and 610 is obtained, and this is output as the correction level Ld of the cell of interest 608.

Finally, the roadside structure judging section 211 compares the threshold level TH with the correction level Ld. If the relation of Ld> TH is satisfied, the cell of interest 608 has a spectrum due to the reflection from the roadside structure 406. The spectrum data is output as a determination signal H indicating the detection state of the roadside structure 406.

By performing the above processing sequentially for all the frequency cells while shifting the moving window 608 along the frequency cells, it is possible to detect the spectrum data due to the reflection from the roadside building 406.

On the other hand, the roadside structure 4 is located in front of the vehicle 601.
06 and there is only the preceding vehicle 402 (see FIG. 19) as the detection target, the spectrum data detected by the own vehicle 601 has the occupied bandwidth Δ as described above.
fw has a narrow data distribution (see FIG. 20).

Therefore, the cell of interest 608 corresponding to the spectrum data due to the reflection from the preceding vehicle 402 and the reference cell 60 corresponding to the spectrum data of the noise on both sides thereof
Cell of interest 60 consisting of the average output of the sum of 9 and 610
8 and the correction level Ld are both the threshold level T
Therefore, the target preceding vehicle 402 is not mistaken for the roadside structure 406.

Next, the operation of calculating the distance Re to the roadside structure 406 by the roadside structure distance measuring section 212 will be described. First, since the roadside structure 406 is stationary on the road, the spectrum data in the DOWN section obtained by the detection processing of the roadside structure 406 shifts by a frequency corresponding to the Doppler component of the own vehicle speed Vw of the own vehicle 601. ing.

Therefore, the Doppler shift component based on the own vehicle speed Vw is calculated and subtracted from the spectral frequency of the roadside structure 406 to obtain the Doppler shift component up to the roadside structure 406 (guard rail) as in the following equation (5). Distance R
e is calculated.

Re = (fbdown−2 · fo · V / c) × {Tm · c / (4 · Δf)} (5)

However, in equation (5), Tm, fo,
c, fbdown, λ, Δf, R, and V are the same as described above. Here, the roadside structure 4 in the DOWN section is used.
The distance Re to the roadside structure 406 was calculated using only the spectral data from the reflection from the laser beam 06.
The distance Re to the roadside structure 406 using only the spectrum data due to the reflection from the roadside structure 406 in the P section.
May be calculated.

As described above, by calculating the distance Re using only one-sided chirp (DOWN section or UP section), the calculation load of the signal processing section 21 can be reduced. Further, when the roadside structure 406 is detected, it is possible to accurately identify whether the target is the preceding vehicle 402 or the roadside structure 406 ahead.

Embodiment 2 Note that the roadside structure detection unit 7 according to the first embodiment determines that the reflective object 3 in front of the host vehicle 601 is the roadside structure 406 (guardrail), and determines the distance Re to the roadside structure 406. However, it may be configured such that the existence of the curved road 405 (see FIG. 2) can be determined.

Hereinafter, a second embodiment of the present invention in which the curved road 405 can be determined will be described with reference to the drawings. FIG. 4 is a block diagram showing a second embodiment of the present invention. In FIG. 4, the same components as those described above are denoted by the same reference numerals and will not be described in detail. The relationship between the host vehicle 601 and the curved road 405 is as shown in FIG. 2, and the spectrum data obtained by the host vehicle 601 is as shown in FIG.

Reference numerals 7A and 21A correspond to the roadside structure detecting section 7 and the signal processing section 21, respectively. In this case, the roadside structure detection unit 7A in the signal processing unit 21A includes the roadside structure information storage unit 2 in addition to the above-described configuration.
14 and a curved road determination unit 215.

The roadside structure information storage unit 214 stores, as roadside structure information, the distance Re to the roadside structure 406 and the signal level of the spectrum data due to the reflection from the roadside structure 406.

The curved road determination unit 215 compares the data on the roadside structure 406 stored in the roadside structure information storage unit 214 with the data on the current roadside structure 406, and It is determined whether or not the forward traveling road is a curved road 405, and if it is a curved road 405, a curved road determination signal K is output.

Next, the operation of the second embodiment of the present invention shown in FIG. 4 will be described. The operations of the transmission / reception unit 1 and the A / D converter 201 to the roadside structure distance measurement unit 212 in the signal processing unit 21A are the same as those described above (see FIG. 1), and thus will not be described here.

First, the roadside structure information storage unit 214 stores the distance Re to the roadside structure 406 calculated by the roadside structure distance measuring unit 212 and the roadside structure 4 as roadside structure information.
The signal level of the spectrum data (judgment signal H from the roadside structure judging unit 211) due to the reflection from 06 is stored.

The curved road determination unit 215 is a unit that stores the past roadside structure 406 stored in the roadside structure information storage unit 214.
(The past distance Re and the signal level) are compared with the current data of the roadside structure 406 (the current distance Re and the signal level), and the distance Re to the roadside structure 406 is reduced, and When the signal level becomes high, it is determined that the road ahead of the host vehicle 601 is a curved road 405, and a curved road determination signal K is output.

The operation in an actual traveling environment will be described below with reference to FIGS. In FIG.
810a is a straight road, 601a is the own vehicle after a lapse of a predetermined time, 406b is an irradiation part after the lapse of the predetermined time, Ea and Eb are both end positions of the irradiation part 406a of the initial transmission wave W1 from the own vehicle 601 and Ec And Ed are both end positions of the irradiated portion 406b by the transmission wave W1 from the own vehicle 601b after a predetermined time has elapsed.

As shown in FIG. 5, the continuous roadside structure 4
06 (straight road alongside road) 810
Is assumed that the own vehicle 601 is traveling straight. First, in the initial state, the transmission wave W1 emitted from the host vehicle 601 is applied to the irradiation portion 406a of the roadside structure 406.

Subsequently, a predetermined time (for example, several hundred meters)
Second) transmitted wave W1 radiated from own vehicle 601a after elapse
Is irradiated on the irradiation part 406b. Here, own vehicle 6
01 is traveling on a straight road 810, the vehicle 60
If the vibration of 1 is not considered, the distance between both ends Ea and Eb of the irradiation portion 406a and the distance between both ends Ec and Ed of the irradiation portion 406b are equal to each other.

Therefore, the host vehicle 601 moves on a straight road 810
Is steady, the distance Re to the roadside structure 406 (guardrail) output from the roadside structure detection unit 7A and the amplitude level thereof are equal.

Next, as shown in FIG. 6 and FIG. 7, a case where the host vehicle 601 is running short of a curved road 405 will be described as an example. First, in the initial state, the transmission wave W1 from the own vehicle 601 is irradiated with the irradiation portion 406 shown in FIG.
a.

Subsequently, after a lapse of a predetermined time, the own vehicle 601 travels to the position shown in FIG.
Of the irradiation part 406a is small, and the distance Re to the host vehicle 601 is greatly reduced.

That is, as shown in FIGS. 6 and 7,
When the host vehicle 601 enters the curved road 405, unlike when traveling on a straight road 810, the roadside structure ranging unit 2
Roadside structure 406 (irradiated portion 406) calculated in
The distance Re to a) becomes shorter, and therefore, the amplitude level of the reflected wave (received wave W2) from the irradiated portion 406a (guardrail) of the roadside structure 406 also becomes larger.

The curve road determination unit 25 compares the current distance Re and the amplitude level to the roadside structure 406a with the past distance Re and the amplitude level stored in the roadside structure information storage unit 214. Roadside structure 40 measured
6 becomes shorter and the amplitude level of the received wave W2 becomes larger, the front of the host vehicle 601 becomes curved 4
05 is determined. As a result, the curve road determination signal K
, Various indications and warnings can be shown to the driver.

Embodiment 3 In the first and second embodiments, one transmitting antenna 10
4 and the receiving antenna 105 are provided, but a plurality of transmitting antennas and receiving antennas may be provided so that the orientation of the roadside structure (reflective object 3) can be detected.

Hereinafter, a third embodiment of the present invention having a plurality of transmitting antennas and receiving antennas will be described with reference to the drawings. FIG. 8 is a block diagram showing a third embodiment of the present invention. Components similar to those described above are given the same reference numerals and will not be described in detail.

In FIG. 8, 1B is a transmitting / receiving section, 7B is a roadside structure detecting section, and 21B is a signal processing section. In this case, the transmitting / receiving section 1B includes a plurality of transmitting antennas 104a to 104c and a receiving antenna 105a
To 105c to enable scanning transmission and scanning reception.

The transmitting / receiving section 1B includes switching means 107 and 108 having a rotary switch function. One of the switching means 107 is inserted between the circulator 103 and each of the transmitting antennas 104a to 104c.
The other switching means 108 is connected to each of the receiving antennas 105a to 105a.
05c and the mixer 106.

Roadside structure detecting section 7 in signal processing section 21B
B includes a roadside structure information storage unit 214B related to the roadside structure distance measuring unit 212 and a roadside structure direction determination unit 217 related to the roadside structure information storage unit 214B.

The roadside structure information storage unit 214B stores a distance Re to the roadside structure 406 based on the spectrum data obtained from the three receiving antennas 105a to 105c,
The signal level (amplitude information) of the spectrum data due to the reflection from the roadside structure 406 is stored.

The road-side structure direction determination unit 217 determines the direction of the road-side structure 406 based on the distance Re and the amplitude information in the data on the road-side structure 406 stored in the road-side structure information storage unit 214B. An azimuth determination signal F is output.

Next, the operation of the third embodiment of the present invention shown in FIG. 8 will be described. First, the switches 107 and 108 in the transmitting / receiving unit 1B are
4a to 104c and receiving antennas 105a to 105c
Is switched every modulation period Tm (see equation (5)).

At this time, the transmission antennas 104a to 104a to
4c and the receiving antennas 105a to 105c, the transmitting antenna 104a and the receiving antenna 105a, the transmitting antenna 104b and the receiving antenna 105b, and the transmitting antenna 104c and the receiving antenna 105c are synchronously switched, respectively.

Hereinafter, similarly to the above, the distance Re obtained by the roadside structure distance measuring section 212 in the signal processing section 21B is obtained.
(Ranging data) are transmitted antennas 104a to 104c.
And for each of the receiving antennas 105a to 105c,
The information is stored in the roadside structure information storage unit 214B.

The roadside structure azimuth determination unit 217 includes three sets of transmitting antennas 104a in the roadside structure information storage unit 214B.
１０４104c and the reception antennas 105a〜105c, the distance Re and the signal level are compared, and the orientation of the roadside structure 406 is determined.

Next, a specific processing operation of the roadside structure azimuth determining unit 217 will be described with reference to FIGS. FIG. 9 shows vehicle 6 according to Embodiment 3 of the present invention.
01 and FIG. 10 show three sets of transmitting antennas 104a to 104c and receiving antenna 1
FIG. 13 is an explanatory diagram showing each spectrum data obtained in 05a to 105c, and FIG. 13 is a flowchart showing a roadside structure determination processing operation and an azimuth determination processing operation by the roadside structure detection unit 7B.

In FIG. 9, W1a to W1c are transmission waves radiated from the respective transmitting antennas 104a to 104c, the transmitting wave W1a is a beam radiated from the right transmitting antenna 104a, and the transmitting wave W1b is a central transmitting antenna 1
The beam radiated from the transmission antenna 04c and the transmission wave W1c correspond to the beam radiated from the left transmission antenna 104c, respectively.

Reference numeral 406B denotes an irradiated portion of the roadside structure 406 (guardrail) irradiated by the central transmission wave W1b;
Reference numeral 406C denotes an irradiated portion of the roadside structure 406 irradiated by the left transmission wave W1c.

As shown in FIG. 9, when the vehicle 601 is traveling on a two-lane straight road 810, each transmitting antenna 104
Transmission waves W1a to W1c from a to 104c are radiated toward the front and roadside structures 406.

Among the transmission waves W1a to W1c, there is no irradiated portion on the roadside structure 406 by the right transmission wave W1a, and the irradiation portion 406b by the central transmission wave W1b is relatively small, and the left transmission wave W1c is relatively small. Irradiated part 406 by
c becomes relatively large.

The right receiving antenna 105a receives the reflected wave of the right transmission wave W1a, and the center receiving antenna 105b receives the radiated portion 406 of the left transmission wave W1b.
b, and receives the reflected wave from
Receives the reflected wave from the irradiated portion 406c due to the transmission wave W1c on the left side.

FIG. 10 shows the spectrum data received by the left receiving antenna 105c, and FIG. 11 shows the spectrum data received by the center receiving antenna 105b.
The spectrum data received by the right receiving antenna 105a is as shown in FIG.

10 to 12, each spectrum data (bar graph waveform) is corrected to a correction level Ld (see a solid line) by a spectrum correction section 210, and the amplitude is compared with a threshold level TH.

In FIG. 10, EA and EB are upper and lower edges of a frequency bin region where the correction level Ld of the left spectrum data is larger than the threshold level TH.

Similarly, in FIG. 11, EC and ED
Are upper and lower edges of the frequency bin region where the correction level Ld of the right spectrum data is larger than the threshold level TH.

In FIG. 13, steps S2 to S10
Corresponds to the processing logic of the roadside structure determining unit 211,
Steps S <b> 11 to S <b> 13 are the roadside structure direction determination unit 217.
It corresponds to the processing logic.

First, the spectrum correction section 210 in the signal processing section 21B converts the spectrum data of the beat signal B based on the reception signals of the reception antennas 105a to 105c into a DO signal.
The data is read from the WN section spectrum data storage unit 205 (step S1), and a correction level Ld is generated as correction spectrum data (step S2). In step S2, first, the reception wave W2 based on the transmission wave W1a on the left side
To correct the spectral data based on

Subsequently, an amplitude comparison (Ld> TH?) Between the correction spectrum (correction level Ld) of the left beam generated in step S2 and the threshold level TH is performed (step S3).

At this time, with respect to the spectrum data of the left beam, the frequency bin areas EA to EB (see FIG. 10) corresponding to the irradiation part 406C (see FIG. 9) are detected as roadside structures 406 (Ld> TH). .

In step S3, if Ld ≦ TH
If the determination is NO, the reflected wave of the left beam (transmitted wave W1c) is not detected (step S3).
C), and proceed to the next correction processing step S5.

In step S3, Ld> TH
If determined to be (YES), the roadside structure determining unit 211 outputs a determination signal H indicating the detection state of the roadside structure 406, and the roadside structure distance measuring unit 212 stores the determination signal H ( Step S4), proceed to the correction processing step S5.

In step S5, a correction spectrum (correction level Ld) corresponding to the reflected wave of the center beam is generated. Subsequently, an amplitude comparison (Ld> TH?) Between the correction level Ld of the center beam generated in step S5 and the threshold level TH is performed (step S6).

At this time, with respect to the spectrum data by the center beam, the frequency bin areas EC to ED (see FIG. 10) corresponding to the irradiation part 406B (see FIG. 9) are detected as roadside structures 406 (Ld> TH). .

In step S6, if Ld ≦ TH
If the determination is NO (that is, NO), the reflected wave of the center beam (transmitted wave W1b) is not detected (step S6).
B), and proceed to the next correction processing step S8.

In step S6, Ld> TH
If determined to be (YES), the roadside structure determining unit 211 outputs a determination signal H indicating the detection state of the roadside structure 406, and the roadside structure distance measuring unit 212 stores the determination signal H ( Step S7), and proceed to the correction processing step S8.

In step S8, a correction spectrum (correction level Ld) corresponding to the reflected wave of the right beam is generated. Subsequently, an amplitude comparison (Ld> TH?) Between the correction level Ld of the right beam generated in step S8 and the threshold level TH is performed (step S9).

At this time, in the example of FIG. 9, as for the spectrum data of the right side beam (transmission wave W1a), since the irradiation part of the roadside structure 406 by the transmission wave W1a does not exist, the roadside structure 406 (Ld> TH) Will not be detected.

In step S9, if Ld ≦ TH
If it is determined as NO (ie, NO), the reflected wave of the right beam (transmitted wave W1a) is not detected (step S9).
A), the process proceeds to the determination processing step S11 by the roadside structure direction determination unit 217.

In step S9, Ld> TH
If determined to be (YES), the roadside structure determining unit 211 outputs a determination signal H indicating the detection state of the roadside structure 406, and the roadside structure distance measuring unit 212 stores the determination signal H ( Step S10), azimuth determination processing step S1
Proceed to 1.

The road-side structure direction determination unit 217 determines the direction of the road-side structure 406 based on the data on the road-side structure 406 obtained by the three sets of transmitting and receiving antennas. First, in step S11, it is determined whether or not spectral data of a reflected wave from the roadside structure 406 due to the center beam (transmitted wave W1b) exists.

If it is determined that the spectrum data by the center beam exists (ie, YES), the center beam detection process (step S11B) is executed, and FIG.
Is completed.

In step S11, there is no spectrum data based on the center beam (that is, N
If it is determined as O), subsequently, the left beam (transmitted wave W1)
It is determined whether or not the spectrum data of the reflected wave from the roadside structure 406 according to c) exists (step S1).
2).

If it is determined that the spectrum data of the left beam exists (that is, YES), the left beam detection processing (step S12C) is executed, and FIG.
Is completed.

In step S12, there is no spectrum data of the left beam (that is, N
If it is determined to be O), then the right beam (transmitted wave W1)
It is determined whether or not the spectrum data of the reflected wave from the roadside structure 406 according to a) exists (step S1).
3).

If it is determined that the spectrum data of the right beam exists (that is, YES), the right beam detection processing (step S13A) is executed, and FIG.
Is completed.

In step S13, there is no spectrum data for the right beam (that is, N
If it is determined to be O), the processing in FIG. By the above processing, the detected orientation of the roadside structure 406 can be detected.

In the example of FIG. 9, the left beam (transmitted wave W1c)
And the roadside structure 4 by the central beam (transmitted wave W1b)
06 is detected, the roadside structure direction determination unit 217
Outputs a direction determination signal F indicating the left direction and the front direction as the detected direction of the roadside structure 406.

Embodiment 4 It should be noted that the first to the first embodiments
3, the spectrum correction unit 210 uses the spectrum data (for example, DOWN section spectrum data D
d) Direct correction spectrum data (correction level Ld)
However, the influence of the spectrum of the preceding vehicle may be removed so that only the roadside structure 406 can be detected more reliably.

A fourth embodiment of the present invention in which the influence of the vehicle spectrum is removed from the spectrum data will be described below with reference to the drawings. FIG. 14 is a block diagram showing a fourth embodiment of the present invention. Components similar to those described above are designated by the same reference numerals and will not be described in detail. In FIG. 14, the signal processing unit 21C includes a vehicle spectrum removing unit 21.
Only the point of adding 8 is different from the above (see FIG. 4).

The vehicle spectrum removing section 218 has a DOWN
It is inserted between the interval spectrum data storage unit 205 and the DOWN interval peak detection unit 207 and the spectrum correction unit 210. From the DOWN interval spectrum data Dd, a peak frequency spectrum having a large signal level of the DOWN interval peak frequency Pfd is obtained. The removed data is used as a spectrum correction unit 210 in the roadside structure detection unit 7A.
To enter.

Next, the processing operation of the fourth embodiment of the present invention shown in FIG. 14 will be specifically described with reference to FIG. 15 and FIG. FIG. 15 is an explanatory diagram showing a bar graph of spectrum data before removing the vehicle spectrum, FIG.
FIG. 6 is an explanatory diagram showing a bar graph of the spectrum data after the vehicle spectrum removal processing.

For example, when the roadside structure 406 (see FIG. 9) and the preceding vehicle exist in front of the own vehicle 601, D
As shown in FIG. 15, in the OWN section spectrum data Dd, spectrum data (vehicle spectrum) 701 of the preceding vehicle and spectrum data 606 of the roadside structure 406 overlap with each other.

If the spectrum data of FIG. 15 is directly input to the spectrum correcting section 210 to generate the correction level Ld, the roadside structure determining section 211 compares the correction level Ld with the threshold level TH,
Frequency bins where d> TH (from section EE to EF)
Is erroneously determined to be spectrum data due to reflection from the roadside structure 406.

Therefore, the roadside structure distance measuring section 212
Actual spectrum data 606 from the roadside structure 406
The distance Re to the roadside structure 406 is erroneously measured based on a wider range of spectral data.

Therefore, the vehicle spectrum removing section 218
A spectrum correction process is performed on the DOWN section spectrum data Dd shown in FIG. The signal levels Aw2 and Aw3 of the frequency bins fp2 and fp3 are reduced to the noise floor level as shown in FIG.

By removing the vehicle spectrum in this manner, the DOWN section peak frequency Pf in FIG.
frequency bin fp1 and frequency bin fp corresponding to d
2 and fp3, as shown in FIG.
It is converted to noise floor levels and is substantially removed from the spectral data.

Next, the spectrum corrector 210
As described above, the correction level Ld is obtained for the corrected spectrum data after the vehicle spectrum removal processing. Therefore, the roadside structure determining unit 211 can detect an accurate frequency bin (sections EG to EH) that substantially matches the spectrum data 606 of the actual roadside structure 406.

Similarly, the roadside structure distance measuring section 212 can accurately measure the distance Re to the roadside structure 406 without being affected by the vehicle spectrum data 701. It is needless to say that the respective working effects can be achieved by combining the first to fourth embodiments.

[0154]

As described above, according to the first aspect of the present invention, the modulation voltage generating means mounted on the own vehicle to generate the FM-CW wave, and for transmitting the FM-CW wave as the transmission wave. A transmitting antenna, a receiving antenna for receiving the transmitted wave reflected by the reflecting object as a received wave, a mixer for mixing the transmitted wave and the received wave to generate a beat signal, and a vehicle for performing frequency analysis of the beat signal and performing a frequency analysis on the beat signal. An obstacle detection radar device including a signal processing unit that measures a relative speed and a distance between the roadside structure and the reflecting object, wherein the signal processing unit includes a roadside structure detection unit for detecting a roadside structure, The detection unit includes a spectrum correction unit that corrects the spectrum data of the beat signal, and a roadside that determines the roadside structure by comparing the corrected spectrum data with a threshold level corresponding to the roadside structure. Since the structure determination unit and the road-side structure distance measurement unit that calculates the distance from the vehicle to the road-side structure according to the determination result of the road-side structure determination unit are included, whether the reflective object is the preceding vehicle or the road-side structure is determined. There is an effect that an obstacle detection radar device that can be identified is obtained.

According to a second aspect of the present invention, in the first aspect, the road-side structure ranging section calculates the distance to the road-side structure based on the spectrum frequency of the spectrum data. This has the effect of providing an obstacle detection radar device that can accurately measure the distance to the roadside structure.

According to a third aspect of the present invention, in the second aspect, there is provided an own-vehicle speed detecting means for detecting the speed of the own vehicle as the own-vehicle speed. Including Doppler shift component calculating means for calculating a Doppler shift component, the distance to the roadside structure is calculated based on the spectral frequency obtained by one-side chirp of the spectrum data and the Doppler shift component of the own vehicle speed. Therefore, there is an effect that an obstacle detection radar device capable of accurately measuring the distance to the roadside structure can be obtained.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the roadside structure detecting section is configured to determine a distance to the roadside structure and a signal of spectrum data by the roadside structure. A road-side structure information storage unit that stores the level and a curve that determines whether the front of the host vehicle is a curved road by comparing past data and current data stored in the road-side structure information storage unit. Since it includes a road determination unit,
This has the effect of providing an obstacle detection radar device that can notify the driver that a vehicle is ahead of a curved road and call attention.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, an antenna scanning means for scanning a receiving antenna is provided, and the signal processing unit includes the antenna scanning means. Since it includes a reception wave level recognition means for recognizing a change in the level of the reception wave,
There is an effect that an obstacle detection radar device that can recognize the orientation of the roadside structure can be obtained.

According to a sixth aspect of the present invention, in the fifth aspect, the antenna scanning means effectively switches a plurality of transmitting antennas and receiving antennas, and sequentially switches each transmitting antenna and receiving antenna one by one. And a plurality of transmitting antennas and receiving antennas are provided corresponding to at least the front center and the left and right azimuths of the host vehicle, so that the azimuth of the roadside structure ahead can be reliably recognized. There is an effect that an obstacle detection radar device that can perform the obstacle detection can be obtained.

According to a seventh aspect of the present invention, in the sixth aspect, the received wave level recognizing means determines the amplitude data on the roadside structure of the received wave obtained from the front of the own vehicle and the right and left of the own vehicle. Since the received wave obtained from both ends is compared with the amplitude data on the roadside structure, the level change of the received wave reflected from the roadside structure is recognized,
There is an effect that an obstacle detection radar device that can reliably recognize the direction of the roadside structure ahead is obtained.

According to an eighth aspect of the present invention, in the seventh aspect, the reception wave level recognizing means includes a roadside structure information storage unit related to the roadside structure distance measuring unit, and a roadside structure information storage unit. The roadside structure information storage unit stores the distance to the roadside structure based on the spectrum data obtained from the plurality of receiving antennas, and stores the spectrum data by the roadside structure. The signal level of the roadside structure is stored as amplitude data, and the roadside structure direction determination unit determines the direction of the roadside structure based on the distance to the roadside structure and the amplitude data stored in the roadside structure information storage unit. Therefore, there is an effect that an obstacle detection radar device that can reliably recognize the direction of the roadside structure can be obtained.

According to a ninth aspect of the present invention, in any one of the first to eighth aspects, the signal processing section determines a peak frequency corresponding to a preceding vehicle located ahead of the own vehicle by a spectrum. Includes a vehicle spectrum remover to remove from the data, and the spectrum corrector corrects the spectrum data via the vehicle spectrum remover, so that roadside structures can be reliably recognized without being affected by the vehicle spectrum. There is an effect that an obstacle detection radar device that can perform the operation can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a plan view showing a traveling state for describing an operation of a roadside structure detection process according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating an operation of a roadside structure detection process according to the first embodiment of the present invention.

FIG. 4 is a block diagram showing a second embodiment of the present invention.

FIG. 5 is a plan view showing a radio wave emission range and a radio wave irradiation part in a straight road traveling state according to Embodiment 2 of the present invention.

FIG. 6 is a plan view showing a radio wave emission range and a radio wave irradiation part in a curved road traveling state according to Embodiment 2 of the present invention.

FIG. 7 is a plan view showing a radio wave radiation range and a radio wave irradiation part in a traveling state on a curved road according to Embodiment 2 of the present invention.

FIG. 8 is a block diagram showing a third embodiment of the present invention.

FIG. 9 is a plan view showing a traveling state for explaining a processing result of a roadside structure detection processing according to Embodiment 3 of the present invention.

FIG. 10 is an explanatory diagram showing a spectrum of a left beam processing result of the roadside structure detection processing according to the third embodiment of the present invention.

FIG. 11 is an explanatory diagram showing a spectrum of a center beam processing result of the roadside structure detection processing according to the third embodiment of the present invention.

FIG. 12 is an explanatory diagram showing a spectrum of a right beam processing result of the roadside structure detection processing according to the third embodiment of the present invention.

FIG. 13 is a flowchart showing a roadside structure detection process according to Embodiment 3 of the present invention.

FIG. 14 is a block diagram showing a fourth embodiment of the present invention.

FIG. 15 is an explanatory diagram showing, as a spectrum, a processing result of a roadside structure detection process according to the fourth embodiment of the present invention.

FIG. 16 is an explanatory diagram showing a processing result after a vehicle spectrum is removed in the roadside structure detection processing according to the fourth embodiment of the present invention.

FIG. 17 is a block diagram showing an obstacle detection radar apparatus using a conventional FM-CW wave.

FIG. 18 is an explanatory diagram showing a principle of a beat frequency obtained by a general FM-CW radar device.

FIG. 19 is a plan view showing a running state when a conventional obstacle detection radar device radiates radio waves to an automobile.

FIG. 20 is an explanatory diagram showing a spectrum shape obtained by irradiating a vehicle with radio waves using a conventional obstacle detection radar device.

FIG. 21 is a plan view showing a running state when a conventional obstacle detection radar device radiates radio waves to a roadside structure.

FIG. 22 is an explanatory diagram showing a spectrum shape obtained by irradiating a roadside structure with radio waves by a conventional obstacle detection radar device.

FIG. 23 is an explanatory diagram showing an example of spectrum data obtained by reflection from a roadside structure in a conventional obstacle detection radar device.

FIG. 24 is an explanatory diagram showing an example of arrangement of a general roadside structure.

[Explanation of symbols]

1, 1B transmitting / receiving unit, 3 reflective object, 6 target processing unit,
7, 7A, 7B Roadside structure detector, 21, 21A-2
1C signal processing unit, 101 modulation voltage generator, 102
VCO (voltage controlled oscillator), 104, 104a to 104
c transmitting antenna, 105, 105a to 105c receiving antenna, 106 mixer, 107, 108 switching means, 204 UP section spectrum data storage section, 205
DOWN section spectrum data storage unit, 206 UP
Section peak detecting section, 207 DOWN section peak detecting section, 209 arithmetic processing section, 210 spectrum correcting section,
211 roadside structure determination unit, 212 roadside structure ranging unit,
214, 214B Roadside structure information storage unit, 215 Curve road determination unit, 217 Roadside structure direction determination unit, 218
Vehicle spectrum remover, 406 Roadside structure, 601
Own vehicle, B beat signal, Aw signal level, Dd
DOWN section spectrum data, F direction determination signal, f
w frequency (frequency bin), H judgment signal, K curve road judgment signal, Ld correction level, Pfd DOWN section peak frequency, R, Re distance, TH threshold level, V relative speed, Vw own vehicle speed, Vm modulation voltage,
W1, W1a to W1c transmission wave, W2 reception wave.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G01S 13/93 G01S 13/93 Z

Claims (9)

[Claims] 1. A modulation voltage generation means mounted on a host vehicle to generate an FM-CW wave, a transmission antenna for transmitting the FM-CW wave as a transmission wave, and the transmission wave reflected by a reflecting object A reception antenna for receiving the reception wave as a reception wave, a mixer that mixes the transmission wave and the reception wave to generate a beat signal, And a signal processing unit for measuring a distance, the signal processing unit includes a roadside structure detection unit for detecting a roadside structure, the roadside structure detection unit, A spectrum correction unit for correcting the spectrum data of the beat signal; and comparing the corrected spectrum data with a threshold level corresponding to the roadside structure. And a road-side structure ranging unit that calculates a distance from the vehicle to the road-side structure according to the determination result of the road-side structure determination unit. Obstacle detection radar device. 2. The obstacle detection radar device according to claim 1, wherein the road-side structure distance measuring unit calculates a distance to the road-side structure based on a spectrum frequency of the spectrum data. 3. A self-vehicle speed detecting means for detecting a speed of the self-vehicle as a self-vehicle speed, wherein the road-side structure distance measuring section includes a Doppler shift component calculating means for calculating a Doppler shift component based on the self-vehicle speed. The distance to the roadside structure is calculated based on a spectrum frequency obtained by one-side chirp of the spectrum data and a Doppler shift component of the own vehicle speed. Obstacle detection radar device. 4. A roadside structure information storage unit that stores a distance to the roadside structure and a signal level of spectrum data from the roadside structure, and the roadside structure information storage unit. And a curve road determining unit that determines whether or not the front of the host vehicle is a curved road by comparing past data and current data stored in the vehicle. The obstacle detection radar device according to any one of the above. 5. An antenna scanning unit for scanning the reception antenna, wherein the signal processing unit includes a reception wave level recognition unit for recognizing a level change of the reception wave in association with the antenna scanning unit, The obstacle detection radar device according to any one of claims 1 to 4, wherein the direction of the roadside structure is recognized. 6. The antenna scanning means includes a plurality of transmitting antennas and receiving antennas, and a switching means for sequentially switching and enabling each of the transmitting antennas and the receiving antennas one by one. The obstacle detection radar device according to claim 5, wherein the reception antenna is provided at least corresponding to a front center and a left and right direction of the vehicle. 7. The received wave level recognizing means relates to amplitude data relating to a roadside structure of a received wave obtained from the front of the host vehicle and to a roadside structure of a received wave obtained from both left and right ends of the host vehicle. The obstacle detection radar device according to claim 6, wherein a level change of a reception wave reflected from the roadside structure is recognized by comparing the amplitude data with the amplitude data. 8. The received wave level recognizing means includes a roadside structure information storage unit associated with the roadside structure distance measurement unit, and a roadside structure direction determination unit associated with the roadside structure information storage unit. The roadside structure information storage unit stores the distance to the roadside structure based on the spectrum data obtained from the plurality of receiving antennas, and sets the signal level of the spectrum data by the roadside structure as the amplitude data. The roadside structure direction determination unit stores the roadside structure information based on the distance to the roadside structure and the amplitude data stored in the roadside structure information storage unit, and determines the direction of the roadside structure. The obstacle detection radar device according to claim 7. 9. The vehicle according to claim 1, wherein the signal processing unit includes a vehicle spectrum removing unit that removes a peak frequency corresponding to a preceding vehicle located in front of the host vehicle from the spectrum data. The obstacle detection radar device according to any one of claims 1 to 8, wherein the spectrum data via the removal unit is corrected.