JP2008020432A - Radar system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide radar system with rather less hardware and lower throughput to improve target detection performance for high mobility target the motion of which is not previously assumable with ease. <P>SOLUTION: This radar system makes pulse compression of receiver video signal, computes distance from signal generated by the pulse compression to target, and then computes relative velocity or relative distance with the target from difference in distance based on strength of the generated signal by each pulse compression of up chirp receiver video signal and down chirp receiver video signal, respectively. Additionally, by each pulse compression of up chirp receiver video signal and down chirp receiver video signal, it uses the above relative velocity or relative distance with the target to also compute phase compensation amount allowing equalization of distance from the generated signal to the target, while using the phase compensation amount to compensate phase of the receiver video signal, and then make pulse compression of the phase-compensated receiver video signal. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a radar device that radiates a pulse-modulated radio wave toward a target and uses the radio wave reflected and received by the target as a reception signal.

  Conventional radar equipment transmits a transmission signal in which up-chirp modulation and down-chirp modulation are alternately repeated in the pulse, receives the transmission signal reflected by the target as a reception signal, and converts the reception signal into a digital complex video signal A plurality of signal processing means for performing Doppler correction and pulse compression on the digital complex video signal, and a plurality of correction means for correcting the range of the signal based on the amplitude of the signal generated by the pulse compression. And means for detecting a target by performing coherent integration on the signal generated by the range-corrected pulse compression. And the detection performance of a target is improved by detecting the maximum value of an amplitude from a plurality of coherent integration results (for example, refer to patent documents 1).

  Since this radar apparatus uses a plurality of pulse compression circuits and coherent integrators having different Doppler range correction amounts, the signal-to-noise power ratio (Signal to Noise) is compared with an integration method using only amplitude information represented by non-coherent integration. Improvement of target detection performance can be expected by improving Noise Ratio (SNR).

JP 2000-275332 A

However, in this radar apparatus, it is necessary to prepare a plurality of pulse compression circuits and coherent integrators having different Doppler range correction amounts on the assumption that the target is a constant velocity motion, and there is a problem that hardware and processing amount increase. .
In addition, there is a problem that it is difficult to improve target detection performance for an unexpected motion target.

  An object of the present invention is to provide a radar apparatus capable of improving target detection performance for a high maneuvering target that has a small amount of hardware and processing amount and is difficult to assume a motion in advance.

  In the radar apparatus according to the present invention, the carrier signal is pulse-modulated at a predetermined time interval, and the transmission signal generated by the up-chirp modulation and the down-chirp modulation alternately in the pulse is emitted, reflected by the target, and returned. In a radar apparatus that receives the transmission signal as a reception signal, pulse compression means for pulse-compressing the reception signal, distance measurement means for calculating a distance based on the intensity of the signal generated by the pulse compression, and the up-chirp modulation From the difference in distance based on the intensity of the signal generated by pulse compression of the received signal obtained by transmitting / receiving the transmitted signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal Relative distance / relative speed calculation means for calculating relative speed with respect to the target or relative distance with the target, and the position of the received signal Signal generated by transmitting and receiving the up-chirp modulated transmission signal and a signal generated by pulse-compressing the received signal obtained by transmitting and receiving the down-chirp modulated transmission signal. The phase compensation amount is calculated using the relative speed to the target or the relative speed to the target and the relative distance to the target so that the distance to the target is the same, and the phase compensation amount is used to calculate the phase compensation amount. Compensation means for compensating the phase of the received signal and pulse-compressing the phase-compensated received signal, and integration for adding the signals generated by pulse-compressing the phase-compensated received signal at a plurality of the time intervals. Means.

  In this way, the relative distance to the target or the relative speed with respect to the target is obtained, and the reception signal obtained by transmitting and receiving the up-chirp modulated transmission signal using them and the transmission signal subjected to the down-chirp modulation are transmitted and received. Since the phase compensation amount is calculated so that the distance to the target of the signal generated by pulse compression of each of the obtained reception signals is the same, and the phase compensation of the reception signal is performed using the phase compensation amount, It is possible to provide a radar apparatus with improved target detection performance for a high maneuvering target for which it is difficult to assume a motion in advance.

Embodiment 1 FIG.
As shown in FIG. 1, a radar apparatus according to Embodiment 1 of the present invention includes an antenna 1, a transmitter 2, a chirp signal generator 3, a transmission / reception switch 4, a receiver 5, a signal processor 6, and a display 7. Is provided.
The chirp signal generator 3 generates an up chirp signal and a down chirp signal and outputs them to the transmitter 2.
The transmitter 2 pulse-modulates the carrier signal at a predetermined pulse repetition period, and further repeats up-chirp modulation and down-chirp modulation in the pulse alternately for each pulse according to the up-chirp signal and the down-chirp signal, thereby transmitting the transmission RF signal. Generate and output to the transmission / reception switch 4.
The transmission / reception switch 4 outputs the transmission RF signal input from the transmitter 2 to the antenna 1. Then, the transmission RF signal is radiated from the antenna 1 into the air.

The transmission RF signal radiated into the air is reflected by the target and enters the antenna 1 as a reflected RF signal.
Therefore, the antenna 1 receives the incident reflected RF signal and outputs it to the transmission / reception switch 4 as a received RF signal.
The transmission / reception switch 4 outputs the reception RF signal input from the antenna 1 to the receiver 5.
The receiver 5 amplifies the received RF signal input from the transmission / reception switch 4 and after phase detection, converts it to a received video signal and outputs it to the signal processor 6.

The transmission RF signal whose pulse is up-chirp-modulated is reflected by the target, is incident on the antenna 1 as a reflected RF signal, and is received to generate a reception RF signal. The reception RF signal is converted into a reception video signal. However, in the following description, this received video signal is referred to as an up-chirp received video signal.
Further, the transmission RF signal whose pulse is down-chirp modulated is reflected by the target, is incident on the antenna 1 as a reflected RF signal, and is received to generate a reception RF signal. The reception RF signal is converted into a reception video signal. However, in the following description, this received video signal is referred to as a down-chirp received video signal.
In the following description, the time interval is referred to as a predetermined pulse repetition interval (pulse repetition interval) of pulse modulation and is abbreviated as PRI.

  As shown in FIG. 1, the signal processor 6 according to the first embodiment includes a pulse compression unit 11, a distance measurement unit 12, a relative distance / relative speed calculation unit 13, a phase compensation unit 14, and a second pulse compression unit 15. , Integrating means 16 and speed calculating means 17. The phase compensation means 14 and the second pulse compression means 15 are collectively referred to as compensation means. The signal processor 6 is composed of a computer having a CPU, a RAM, a ROM, and an interface circuit, and arithmetic processing is performed by the CPU in accordance with a program stored in the ROM.

The pulse compression means 11 has a function of compressing the received video signal.
The distance measuring means 12 has a function of calculating a distance based on the intensity of a signal generated by pulse compression that is an output of the pulse compressing means 11.
The relative distance / relative speed calculating means 13 is based on the difference in distance based on the intensity of the signal generated by pulse-compressing the up-chirp received video signal and the down-chirp received video signal calculated by the distance measuring means 12 from the target. It has a function of calculating the relative distance and the relative speed with the target.
The phase compensation means 14 uses the relative speed with respect to the target calculated by the relative distance / relative speed calculation means 13 and uses the target of the signal generated by pulse-compressing the up-chirp received video signal and the down-chirp received video signal. The phase compensation amount is calculated such that the distances to the same are equal, and the phase compensation of the received video signal is performed using the phase compensation amount.
The second pulse compression unit 15 has a function of performing pulse compression on the phase-compensated received video signal that is the output of the phase compensation unit 14.
The integrating unit 16 has a function of adding a plurality of signals generated by pulse-compressing the phase-compensated received video signal that is the output of the second pulse compressing unit 15.
The speed calculation means 17 calculates the relative speed with respect to the target by considering the return of the frequency from the relative speed with respect to the target which is the output of the relative distance / relative speed calculation means 13 with respect to the frequency spectrum which is the output of the integration means 16. Has the function of

Next, the processing operation of the signal processor 6 according to the first embodiment will be described with reference to FIG.
The pulse compression means 11 is a reference signal Ex (m, m _τ ) having a complex conjugate relationship with the input received video signal V (n, m) after A / D conversion and the modulation component of the transmission RF signal. Are subjected to a correlation calculation, and the signal dispersed in the range direction is pulse-compressed. For example, a fast Fourier transform (FFT) can be used to shorten the processing time.

The received video signal V (n, m) input to the pulse compression means 11 is expressed by equation (1). This received video signal V (n, m) is for the nth transmit RF signal. Here, Δt is the A / D sampling period, M is the number of sampling points during 1 PRI, N is the number of pulse hits, A is the amplitude of the transmission RF signal, f ₀ is the transmission center frequency, T _pri is the pulse repetition period, and c is the speed of light. , R ₀ is the initial relative distance to the target at n = 1, m = 1, v is the target relative velocity, plus or minus sign plus is selected when the up-chirp received video signal, minus is the down-chirp received video signal B ₀ is the transmission bandwidth, T ₀ is the transmission time, m is the m th sampling signal, and T _p (= T ₀ ) is the pulse width.

Further, the reference signal Ex (m, m _τ ) used in the pulse compression unit 11 is expressed by Expression (2). Here, the minus of the minus plus sign is selected when the up-chirp received video signal is pulse-compressed, the plus is selected when the down-chirp received video signal is pulse-compressed, and m _τ Δt is an arbitrary time shift in each pulse. To express.

The pulse compression means 11 performs a correlation operation between the received video signal V (n, m) expressed by the equation (1) and the reference signal Ex (m, m _τ ) expressed by the equation (2) as pulse compression. The result R _{V · Ex} (n, m _τ ) is calculated according to equation (3). The signal generated by the pulse compression is the correlation calculation result R _{V · Ex} (n, m _τ ).

When a reflected RF signal is received from a moving target, the distance to the target and the down-chirp affected by the target movement, where the amplitude of the signal generated by pulse compression of the up-chirp received video signal is maximum The distance to the target affected by the target movement in which the amplitude of the signal generated by pulse-compressing the received video signal is maximum changes in a different direction with respect to the relative distance R ₀ from the true target. In the following description, this phenomenon is described as a distance shift.
The distance measuring means 12 is a distance R _peak (n to the target shifted by a distance in which the amplitude of the signal generated by pulse-compressing the received video signal received at the n-th time which is the output of the pulse compressing means 11 is maximum. ) Is calculated according to equation (4).

Here, max_R (R _{V · Ex} (n, m _τ )) represents the distance to the target shifted by the distance at which the amplitude of the correlation calculation result R _{V · EX} (n, m _τ ) is maximum.

The relative distance / relative speed calculating means 13 is a distance-shifted target in which the amplitude of the signal generated by pulse-compressing each of the up-chirp received video signal and the down-chirp received video signal calculated by the distance measuring means 12 is maximized. The relative distance to the target and the relative speed to the target are calculated from the difference in distance.
Here, the initial relative distance R ₀ at n = 1 and m = 1 to the target, and the distance at which the amplitude of the signal generated by pulse-compressing each of the up-chirp received video signal and the down-chirp received video signal is maximum. Derivation of distance differences ΔR _u and ΔR _d from the shifted target distance will be described. ΔR _u and ΔR _d to be described are used when the relative distance / relative speed calculation means 13 calculates the relative distance to the target or the relative speed to the target.
The product of the video signal V (n, m) and the reference signal Ex (m, m _τ ) in the correlation calculation expression (3) is 1 / c ² , Δt ² , m _τ ² Δt ² of the expression (3). Can be approximated to exp (j0), that is, 1 and thus can be rewritten as equation (5).

When m _τ Δt in equation (5) satisfies the relationship of equation (6), V (n, m) · Ex (m, m _τ ) in equation (3) is expressed as in equation (7). The And it turns out that the amplitude of correlation calculation result _{RV * Ex} (n, m ( _tau )) of Formula (3) takes the maximum.

Further, from the equation (6), the initial relative distance R ₀ (= R ₀ −v (n−1) T _pri ) at n = 1 and m = 1 to the target, the up-chirp received video signal, and the down-chirp received video Differences ΔR _u and ΔR _{d in} the distance to the target whose distance has been shifted so that the amplitude of the signal generated by pulse-compressing each signal is maximum are approximately expressed by Expression (8).

However, ΔT = (T ₀ / B ₀ ) · f ₀ .
Further, the up-chirp received video is obtained by using the relational expression of the difference ΔR _u , ΔR _d between the initial relative distance R ₀ to the target and the distance shifted target obtained in Expression (8) and the relative speed v of the target. distance shift amplitude of the generated signal by the amplitude of the generated signal is pulse compression the distance r _u and the down-chirp received video signal to the target that the distance shifted indicating the maximum by a signal pulse compression to indicate the maximum distance r _d to the target that is approximately expressed by equation (9). FIG. 3 illustrates this state.

When a transmit RF signal with up-chirp modulation in the pulse and a transmit RF signal with down-chirp modulation are transmitted at the same time, generated by pulse-compressing each of the up-chirp received video signal and the down-chirp received video signal The relative distance R ′ ₀ and the relative velocity v ′ to the target are obtained from the equations (10) and (11) using the distances r _u and r _d to the target shifted by the distance where the amplitude of the generated signal is maximum. Can be calculated. The calculated relative distance R ′ ₀ and relative speed v ′ with the target are shown with a suffix to distinguish them from the relative distance and relative speed with the true target.

However, in the present invention, the transmission signal in which the up-chirp modulation is performed in the pulse and the transmission signal subjected to the down-chirp modulation are repeatedly transmitted alternately for each PRI. There is a problem of deterioration.
Therefore, in the present invention, the relative distance between the target and the target relative speed can be calculated with high accuracy by considering the target movement between 1 PRI. FIG. 4 shows the distance to the target that has been shifted by the distance in which the amplitude of the signal generated by pulse compression when the target movement between 1 PRI is taken into consideration is maximum.
The distance r _u to the distance-shifted target where the amplitude of the signal generated by pulse compression of the up-chirp received video signal is maximum, and the down-chirp received video signal related to the down-chirp modulated transmission signal transmitted after 1 PRI the amplitude of the signals generated by pulse compression distance r _d to the target that the distance shifted showing a maximum is approximately expressed by formula (12).

Further, the distance r _d to the target whose distance is shifted to show the maximum amplitude of the signal generated by pulse compression of the down-chirp received video signal, and the up-chirp received video related to the up-chirp modulated transmission signal transmitted after ₁ PRI. amplitude of the generated distance shifted signals by pulse compression signal distance r _u to the target indicating the maximum is approximately expressed by formula (13).

Therefore, the relative distance / relative speed calculation means 13 replaces the equations (10) and (11) with the equations (14) and (15), and the relative distance R ′ to the target considering the target movement during 1 PRI. ₀ , the relative speed v ′ with respect to the target is calculated. As the relative speed v ′ with the target in the formula (14), the relative speed v ′ with the target calculated according to the formula (15) is used. As the minus plus sign in the equation (15), minus is selected when changing from an up-chirp received video signal to a down chirp received video signal, and plus is selected when changing from a down chirp received video signal to an up chirp received video signal.
In equations (14) and (15), r _u and r _d indicate that the amplitudes of the signals generated by pulse-compressing the up-chirp received video signal and the down-chirp received video signal that are the outputs of the distance measuring means 12 are maximized. It is selected from the distance R _peak (n) to the target shifted in distance.

Hereinafter, for each PRI, the relative distance from the target calculated by the equations (14) and (15) is described as R ′ (n), and the relative speed with respect to the target is described as v ′ (n), where n = 1, 2, ..., (N-1).
The phase compensator 14 pulse-compresses each of the up-chirp received video signal and the down-video received video signal using the relative speed v ′ (n) with the target input from the relative distance / relative speed calculator 13 for each PRI. Thus, the phase compensation amount φ _cor (n, m) is calculated using the equation (16) so that the distance to the target where the amplitude of the generated signal is maximum is the same. Then, the phase compensation means 14 performs phase compensation of the received video signal V (n, m) using the phase compensation amount φ _cor (n, m) according to the equation (17), and the received video signal V ′ after phase compensation. (N, m) is output.

Here, the minus plus sign is selected to be negative if the received video signal to be phase compensated is an up-chirp received video signal, and positive if it is a down-chirp received video signal.
The second pulse compression means 15 performs pulse compression on the received video signal V ′ (n, m) after phase compensation, which is the output of the phase compensation means 14, in the same manner as the pulse compression means 11 using equation (18). And output a signal R ′ _{V · Ex} (n, m _τ ) generated by pulse compression.

  By performing such processing, as shown in FIG. 5, the distance to the target at which the amplitude of the signal generated by pulse-compressing each of the up-chirp received video signal and the down-chirp video signal subjected to phase compensation is maximized. Are the same.

The integration means 16 performs integration between pulses, and receives as input the signal R ′ _{V · Ex} (n, m _τ ) generated by pulse compression that is the output of the second pulse compression means 15. For example, fast Fourier transform processing or the like is performed, and a signal component for each range bin, that is, a frequency spectrum F (k, m _τ ) is obtained according to the equation (19) to integrate each frequency bin.

Here, k represents a frequency bin number, and FFT_num represents the number of FFT points. When (N-1) is less than the number of FFT points, 0 is supplemented to R ′ _{V · Ex} (n, m _τ ).

The speed calculation means 17 considers the return of the frequency from the relative speed with respect to the target that is the output of the relative distance / relative speed calculation means 13 with respect to the frequency spectrum that is the output of the integration means 16, Find the relative speed.
The speed calculation means 17 calculates the speed band v _band using the equation (20). Further, the speed calculation means 17 calculates the speed resolution Δv of the frequency bin using the equation (21).

Moreover, the speed calculation means 17 calculates | requires speed v _bin (k) of each frequency bin which considered the return of a frequency using Formula (22) based on Formula (20) and Formula (21). Therefore, it is possible to increase the speed resolution by increasing the number of FFT points.

Here, floor (X) represents a maximum integer not exceeding X.
Also, instead of the relative speed with the target that is the output of the relative distance / relative speed calculating means 13, the average relative speed v (bar) of the relative speeds with the plurality of targets that is the output of the average relative speed calculating means 19 is input. In this case, v (bar) is used instead of v ′ (1) in the formula (22). Similarly, when the reference relative speed v (hat) ₀ with respect to the target, which is the output of the reference relative speed / relative acceleration calculating means 20, is input, v ′ (1) in the equation (22) is replaced by v (Hat) ₀ is used.
The speed calculation means 17 outputs the speed of each frequency bin taking into account the frequency spectrum and frequency folding to the display unit 7.
The display unit 7 displays the speed of each frequency bin considering the frequency spectrum from the speed calculation means 17 and the return of the frequency.

  As described above, the radar apparatus according to the first embodiment includes the pulse compression unit 11 that performs pulse compression on the received video signal, and the distance to the target that is shifted by the distance that indicates the maximum amplitude of the signal generated by the pulse compression. Ranging means 12 to be calculated, a difference in distance to a distance-shifted target where the amplitude of a signal generated by pulse compression of each of the up-chirp received video signal and the down-chirp received video signal is maximum, and a target between 1 PRI Relative speed / relative speed calculation means 13 for calculating the relative speed with respect to the target or the relative distance with respect to the target in consideration of the movement, and the phase compensation of the received video signal, the up-chirp received video signal and the down-chirp received video Distance to the target where the amplitude of the signal generated by pulse compression of each signal is maximum The phase compensation amount is calculated using the relative speed with respect to the target so as to be the same, the phase compensation means 14 for compensating the phase of the received video signal using the phase compensation amount, and the phase compensated received video signal A second pulse compression means 15 for pulse compression; an integration means 16 for adding a plurality of signals generated by the pulse compression by the second pulse compression means 15; and a frequency spectrum with respect to a frequency spectrum as an output from the integration means 16. Speed calculating means 17 for calculating the relative speed with respect to the target in consideration of the folding of the target, a plurality of pulse compression circuits with different Doppler-range correction amounts are presumed as in the prior art, assuming a target motion to some extent. Without preparation, it is possible to improve target detection performance and target relative speed measurement accuracy.

Embodiment 2. FIG.
Since the radar apparatus according to the second embodiment of the present invention is different from the radar apparatus according to the first embodiment except for the signal processor 6B, the same parts are denoted by the same reference numerals and the description thereof is omitted. To do. Then, as shown in FIG. 6, the signal processor 6B according to the second embodiment is used as a compensation means instead of the phase compensation means 14 and the second pulse compression means 15 of the signal processor 6 according to the first embodiment. The difference is that the range correction unit 18 is provided, and the rest is the same, and thus the same reference numerals are given to the same parts and the description thereof is omitted.

The range correction unit 18 according to the second embodiment performs pulse compression on each of the up-chirp received video signal and the down-chirp received video signal using the relative speed with respect to the target that is the output of the relative distance / relative speed calculating unit 13. Has a function of correcting the range of the signal generated by pulse compression so that the distance to the target where the amplitude of the signal generated by the maximum is the same.
Next, the processing operation of the signal processor 6B according to the second embodiment will be described with reference to FIG.
The range correction unit 18 calculates the range correction amount R _cor (n) according to the equation (23) using the relative speed with the target that is the output of the relative distance / relative speed calculation unit 13.

Here, v ′ (n) indicates the nth speed measurement result. Plus or minus sign is selected when range correction is performed on the signal generated by pulse compression of the up-chirp received video signal, and minus is selected when range correction is performed on the signal generated by pulse compression of the down-chirp received video signal. Is done.
In addition, the range correction unit 18 converts the range correction amount R _cor (n) into a range correction amount R _{cor_bin} (n) expressed in units of range bins using the equation (24).

Here, Δr (= cΔt / 2) represents a sampling interval.
Then, the range correction means 18 uses the calculated range correction amount R _{cor_bin} (n) and the range of the signal R _{V · Ex} (n, m _τ ) generated by pulse compression according to the equation (25). Correction is performed, and a range-corrected signal R _{V · Ex_cor} (n, m _τ ) is output. By performing such a process, as shown in FIG. 8, the distance to the target where the amplitude of the signal generated by pulse compression and the range correction is maximum can be made the same.

  As described above, the radar apparatus according to the second embodiment replaces the phase compensation means 14 and the second pulse compression means 15 according to the first embodiment with the target that is the output of the relative distance / relative speed calculation means 13. Using relative speed, the range correction amount is calculated so that the distance to the target where the amplitude of the signal generated by pulse compression of each of the up-chirp received video signal and the down-chirp received video signal is the same is the same. Since the range correction means 18 for correcting the range of the signal generated by performing the pulse compression using the range correction amount is provided, the pulse compression for the received video signal can be performed only once, the configuration is simplified, and Thus, it is possible to improve target detection performance and target relative speed measurement accuracy.

Embodiment 3 FIG.
Since the radar apparatus according to the third embodiment of the present invention is different from the radar apparatus according to the first embodiment except for the signal processor 6C, the same components are denoted by the same reference numerals, and description thereof is omitted. To do. As shown in FIG. 9, the signal processor 6C according to the third embodiment is different from the signal processor 6 according to the first embodiment in that an average relative speed calculating unit 19 is added and a phase compensating unit 14B is different. Since the rest is the same, the same parts are denoted by the same reference numerals and the description thereof is omitted.

The average relative speed calculation means 19 receives the relative speed with respect to the target of a plurality of pulses, which is the output of the relative distance / relative speed calculation means 13, and calculates the average relative speed from the results of all measured speeds ((number of pulses−1)). It has a function to calculate speed.
Next, the processing operation of the signal processor 6C according to the third embodiment will be described with reference to FIG.
The average relative speed calculation means 19 calculates the average relative speed v (bar) using the relative speed v ′ (n) for (number of pulses−1) with respect to the target according to the equation (26). The calculated average relative velocity v (bar) is used for compensation of the phase of the received video signal of each pulse.

The phase compensation means 14B is generated by pulse-compressing each of the up-chirp received video signal and the down-chirp received video signal using the average relative speed v (bar) with the target, which is the output of the average relative speed calculating means 19. The phase compensation amount φ _cor (n, m) is calculated according to the equation (27) so that the distances to the target at which the amplitude of the received signal is maximum are the same. Then, the phase compensation unit 14B performs phase compensation of the received video signal according to the equation (28) using the phase compensation amount φ _cor (n, m), and the received video signal V ′ (n, m) after phase compensation. ) Is output.

  Here, the minus plus sign is selected to be minus if the signal to be phase compensated is an up-chirp received video signal, and plus if the signal is a down-chirp received video signal.

  As described above, the radar apparatus according to the third embodiment includes the average relative speed calculation unit 19 that calculates the average relative speed of the speed measurement results for (number of pulses −1), and therefore uses the speed measurement for each pulse. When phase compensation is performed, phase compensation accuracy may decrease due to errors in speed measurement. However, stable phase compensation accuracy can be maintained by using the average relative speed, and stable target detection performance can be improved. Thus, it is possible to improve the target relative speed measurement accuracy.

Embodiment 4 FIG.
Since the radar apparatus according to the fourth embodiment of the present invention is different from the radar apparatus according to the third embodiment except for the signal processor 6D, the same parts are denoted by the same reference numerals and the description thereof is omitted. To do. As shown in FIG. 11, the signal processor 6D according to the fourth embodiment replaces the average relative speed calculation means 19 of the signal processor 6C according to the third embodiment with a reference relative speed / relative acceleration calculation means 20. The phase compensation means 14C is different, and the others are the same, so the same reference numerals are given to the same parts and the description is omitted.

The reference relative speed / relative acceleration calculating means 20 receives the relative speed with respect to the target among a plurality of pulses, which is the output of the relative distance / relative speed calculating means 13, and results of all measured speeds ((number of pulses−1)). From the above, it has a function of calculating a reference relative speed and a relative acceleration with respect to the target by a least square method.
Next, the processing operation of the signal processor 6D according to the fourth embodiment will be described with reference to FIG.
The reference relative speed / relative acceleration calculating means 20 receives a plurality of relative speeds v ′ (n) with respect to the target, which is the output of the relative distance / relative speed calculating means 13, and inputs all measured speeds ((number of pulses−1)). ) From the result, the reference relative speed and relative acceleration with respect to the target are calculated by the least square method.
The speed v (hat) (n) of the time t _n (= (n−1) T _pri ) is the relative acceleration a (hat) with the target, the elapsed time t _n from the first pulse transmission, and the target When the reference relative speed v (hat) ₀ is used, it is expressed by Expression (29).

Therefore, the reference relative speed / relative acceleration calculating means 20 uses the relative speed v ′ (n) with the target at a plurality of pulses, which is the output of the relative distance / relative speed calculating means 13, and uses Expression (30) and Expression (30). According to (31), the relative acceleration a (hat) to the target and the reference relative speed v (hat) ₀ to the target are calculated by the method of least squares.

The phase compensation means 14C uses the relative acceleration a (hat) with the target and the reference relative speed v (hat) ₀ with respect to the target, which are outputs of the reference relative speed / relative acceleration calculation means 20, and uses the up-chirp received video signal and The phase compensation amount φ _cor (n, m) is set according to the equation (32) so that the distance to the target where the amplitude of the signal generated by pulse-compressing each of the down-chirp received video signals is the same is the same. calculate. Then, the phase compensation unit 14C performs phase compensation of the received video signal V (n, m) according to the equation (33) using the phase compensation amount φ _cor (n, m), and the received video signal after phase compensation. V ′ _a (n, m) is output.

  Here, as the minus plus sign, a minus is selected when the phase-compensated received video signal is an up-chirp received video signal, and a plus is selected when the received video signal is a down-chirp received video signal.

As described above, the radar apparatus according to the fourth embodiment includes reference relative speed / relative acceleration calculating means for calculating the reference relative speed and the relative acceleration with respect to the target by the least square method from the speed measurement results for (number of pulses-1). 20 and phase compensation means 14C for performing phase compensation in consideration of acceleration for the received video signal V (n, m) and outputting _a signal V ′ _a (n, m) after phase compensation including the acceleration. Therefore, it is possible to improve the target detection performance for a moving target having acceleration and improve the relative speed measurement accuracy of the target.

Embodiment 5. FIG.
Since the radar apparatus according to the fifth embodiment of the present invention is different from the radar apparatus according to the third embodiment except for the signal processor 6E, the same parts are denoted by the same reference numerals, and the description thereof is omitted. To do. As shown in FIG. 13, the signal processor 6E according to the fifth embodiment is different from the signal processor 6C according to the third embodiment in the average relative speed calculating means 19B, and is otherwise the same. The same parts are denoted by the same reference numerals and the description thereof is omitted.
The average relative speed calculation means 19B according to the fifth embodiment receives the relative distance from the target among a plurality of pulses as the output of the relative distance / relative speed calculation means 13, and the total distance ((number of pulses-1) Min) From the result, it has a function of calculating the average relative speed with the target by the least square method.

Next, the processing operation of the signal processor 6E according to Embodiment 5 will be described with reference to FIG.
The average relative speed calculation means 19B calculates the average relative speed with respect to the target by the least square method from the relative distance to the target with a plurality of pulses, which is the output of the relative distance / relative speed calculation means 13.
The average relative speed calculation unit 19B calculates a relative distance r ′ (n) based on the first distance measurement result R ′ (1) of the relative distance R ′ (n) to the target according to the equation (34). .

The relative distance r (hat) ′ (n) to the target at time t _n (= (n−1) T _pri ) is the initial relative distance between the elapsed time t _n from the first pulse transmission and the target. When r (hat) ₁ ′ is used, the relationship of the average relative speed v (bar) with the target and the equation (35) is established.

  Therefore, the average relative speed calculation means 19B uses the distance measurement result R ′ (n) that is the output of the relative distance / relative speed calculation means 13 and calculates the average relative speed to the target according to the expressions (34) and (36). The speed v (bar) is calculated.

  As described above, the radar apparatus according to the fifth embodiment includes the average relative speed calculation unit 19B that calculates the average relative speed from the distance measurement results for (number of pulses −1), and thus is based on the measurement speed for each pulse. When phase compensation is performed, phase compensation accuracy may decrease due to speed measurement errors. However, since phase compensation is performed using the average relative speed, stable phase compensation accuracy can be maintained, and stable target detection performance can be maintained. And improvement of target relative speed measurement accuracy can be achieved.

Embodiment 6 FIG.
Since the radar apparatus according to the sixth embodiment of the present invention is different from the radar apparatus according to the third embodiment except for the signal processor 6F, the same parts are denoted by the same reference numerals and the description thereof is omitted. To do. Then, as shown in FIG. 15, the signal processor 6F according to the sixth embodiment includes a range correction unit 18B instead of the phase compensation unit 14B and the second pulse compression unit 15 of the signal processor 6C according to the third embodiment. Since the other parts are the same, the same parts are denoted by the same reference numerals and the description thereof is omitted.
The range correction unit 18B according to the sixth embodiment performs pulse compression on each of the up-chirp received video signal and the down-chirp received video signal using the average relative speed with the target that is the output of the average relative speed calculating unit 19. It has a function of correcting the range of the signal generated by pulse compression of the received video signal so that the distance to the target where the amplitude of the generated signal is maximum is the same.

Next, the processing operation of the signal processor 6F according to the sixth embodiment will be described with reference to FIG.
The range correction unit 18B calculates the range correction amount R _cor (n) according to the equation (37) using the average relative speed v (bar) with the target, which is the output of the average relative speed calculation unit 19.

Here, the plus / minus sign is positive if the signal whose range is to be corrected is a signal generated by pulse-compressing the up-chirp received video signal, and the signal generated by pulse-compressing the down-chirp received video signal. If minus is selected.
Then, the range correction unit 18B uses the calculated range correction amount R _cor (n) to generate a signal R _V ·· that is generated by pulse-compressing the received video signal according to the equations (24) and (25). Range correction is performed on _Ex (n, m _τ ), and a signal R _{V · Ex_cor} (n, m _τ ) after the range correction is output.

  As described above, the radar apparatus according to the sixth embodiment replaces the phase compensation unit 14B and the second pulse compression unit 15 of the third embodiment with an average relative speed with respect to the target that is the output of the average relative speed calculation unit 19. Is used to calculate the range correction amount so that the distance to the target where the amplitude of the signal generated by pulse compression of the up-chirp received video signal and the down-chirp received video signal is the same is the same, and the pulse Since the range correction means 18B for performing range correction on the signal generated by the compression is provided, there is a possibility that the range correction accuracy may be lowered due to the speed measurement error when performing the range correction using the speed measurement for each pulse. However, since range correction is performed using the average relative speed, stable range correction accuracy can be maintained, and the received video signal can be filtered. Scan compression is only once, configuration is simplified, and it becomes possible to improve the stability and improve the target detection performance was the target of the relative speed measurement accuracy.

Embodiment 7 FIG.
Since the radar apparatus according to the seventh embodiment of the present invention is different from the radar apparatus according to the sixth embodiment except for the signal processor 6G, the same parts are denoted by the same reference numerals and the description thereof is omitted. To do. As shown in FIG. 17, the signal processor 6G according to the seventh embodiment is different from the signal processor 6F according to the sixth embodiment in the average relative speed calculating means 19B, and the rest is the same. The same parts are denoted by the same reference numerals and the description thereof is omitted.
The average relative speed calculation means 19B according to the seventh embodiment receives the relative distance from the target among a plurality of pulses as the output of the relative distance / relative speed calculation means 13, and the total distance ((number of pulses-1) Min) It has a function to calculate the average relative speed with the target by the least square method from the result.

Next, the processing operation of the signal processor 6G according to Embodiment 7 will be described with reference to FIG.
The average relative speed calculating unit 19B according to the seventh embodiment uses the relative distance R ′ (n) to the target among a plurality of pulses, which is the output of the relative distance / relative speed calculating unit 13, and uses the equation (34), The average relative speed v (bar) with the target is calculated according to Equation (36).

  As described above, the radar apparatus according to the seventh embodiment performs pulse compression on each of the up-chirp received video signal and the down-chirp received video signal using the average relative speed calculated from the relative distance from the target with a plurality of pulses. The range correction means 18B performs range correction on the signal generated by calculating the range correction amount so that the distance to the target where the amplitude of the generated signal is maximum is the same, and performing pulse compression. The range correction accuracy may decrease due to speed measurement error when performing range correction using the pulse-by-pulse measurement speed, but stable range correction accuracy by correcting the range using the average relative speed. Can be maintained, pulse compression is only required for the received video signal, the configuration is simplified, and stable target detection performance is achieved. It is possible to improve the improvement and the target relative speed measurement accuracy.

Embodiment 8 FIG.
Since the radar apparatus according to the eighth embodiment of the present invention is different from the radar apparatus according to the first embodiment except for the signal processor 6H, the same parts are denoted by the same reference numerals and the description thereof is omitted. To do. As shown in FIG. 19, the signal processor 6H according to the eighth embodiment is different from the signal processor 6 according to the first embodiment in phase compensation means 14D. The same reference numerals are attached to these parts, and the description is omitted.
The phase compensation unit 14D according to the eighth embodiment obtains a phase compensation amount by using the relative distance to the target and the relative speed to the target, which are outputs from the relative distance / relative speed calculation unit 13, and performs phase compensation. It has a function.

Next, the processing operation of the signal processor 6H according to the eighth embodiment will be described with reference to FIG.
The phase compensation unit 14D uses the relative distance R ′ (n) to the target and the relative speed v ′ (n) to the target, which are input from the relative distance / relative speed calculation unit 13 for each PRI, and uses the up-chirp received video. The phase compensation amount φ _cor (n, m) according to the equation (38) so that the distance to the target where the amplitude of the signal and the signal generated by the pulse compression of the down-chirp received video signal is the same is the same. ) Is calculated. Then, the phase compensation unit 14D performs phase compensation of the received video signal V (n, m) according to the equation (39) using the phase compensation amount φ _cor (n, m), and the received video signal after phase compensation. V ′ (n, m) is output.

  Here, for the plus / minus sign and minus / plus sign, the upper code is selected when the received video signal to be phase compensated is an up-chirp received video signal, and the lower code is selected when the received video signal is a down-chirp received video signal.

  As described above, the radar apparatus according to the eighth embodiment includes the integration effect regardless of the relative distance from the target by including the relative distance from the target in the compensation term for phase compensation of the received video signal. It is possible to improve the speed measurement, that is, improve the target detection performance for a long-distance moving target and improve the target relative speed measurement accuracy.

Embodiment 9 FIG.
Since the radar apparatus according to the ninth embodiment of the present invention is different from the radar apparatus according to the third embodiment except for the signal processor 6J, the same parts are denoted by the same reference numerals and the description thereof is omitted. To do. As shown in FIG. 21, the signal processor 6J according to the ninth embodiment is different from the signal processor 6C according to the third embodiment in phase compensation means 14E. The same reference numerals are attached to these parts, and the description is omitted.
The phase compensation unit 14E according to the ninth embodiment uses the relative distance to the target that is the output from the relative distance / relative speed calculation unit 13 and the average relative speed to the target that is the output of the average relative speed calculation unit 19. Thus, the phase compensation amount is obtained and the phase compensation is performed.

Next, the processing operation of the signal processor 6J according to Embodiment 9 will be described with reference to FIG.
The phase compensator 14E has a relative distance R ′ (n) to the target, which is the output of the relative distance / relative speed calculator 13, and an average relative speed v (bar) to the target, which is the output of the average relative speed calculator 19. In accordance with Equation (40), the distance to the target where the amplitude of the signal generated by pulse-compressing each of the up-chirp received video signal and the down-chirp received video signal is equal to each other is the same. A compensation amount φ _cor (n, m) is calculated. Then, the phase compensation means 14E performs phase compensation of the received video signal according to the equation (41) using the phase compensation amount φ _cor (n, m), and the received video signal V ′ (n, m) after phase compensation. ) Is output.

  Here, for the plus / minus sign and minus / plus sign, the upper code is selected when the received video signal to be phase compensated is an up-chirp received video signal, and the lower code is selected when the received video signal is a down-chirp received video signal.

  As described above, the radar apparatus according to the ninth embodiment includes the relative distance from the target in the compensation term for phase compensation of the received video signal, and calculates the average relative speed of the speed measurement results for (number of pulses-1). Since the average relative speed calculating means 19 for calculating is provided, stable phase compensation accuracy can be maintained regardless of the relative distance from the target and regardless of the error of the speed measurement result for each pulse, It is possible to improve the target detection performance for a long-distance moving target and improve the target relative speed measurement accuracy.

Embodiment 10 FIG.
Since the radar apparatus according to the tenth embodiment of the present invention is different from the radar apparatus according to the ninth embodiment except for the signal processor 6K, the same parts are denoted by the same reference numerals, and the description thereof is omitted. To do. As shown in FIG. 23, the signal processor 6K according to the tenth embodiment replaces the average relative speed calculating means 19 of the signal processor 6J according to the ninth embodiment with a reference relative speed / relative acceleration calculating means 20. Since the other parts are the same, the same parts are denoted by the same reference numerals and the description thereof is omitted.
The reference relative speed / relative acceleration calculating means 20 according to the tenth embodiment receives the relative speed with respect to the target among a plurality of pulses, which is the output of the relative distance / relative speed calculating means 13, and determines the total measured speed ((number of pulses -1) min) From the result, it has a function of calculating a reference relative speed with respect to the target and a relative acceleration with the target by the least square method.
The phase compensation means 14F according to the tenth embodiment is based on the reference relative speed with respect to the target and the relative acceleration with respect to the target, which are the outputs of the reference relative speed / relative acceleration calculating means 20, and the output of the relative distance / relative speed calculating means 13. Relative distance to a target is input, and pulse compression of each of the up-chirp received video signal and the down-chirp received video signal is performed using the relative distance to the target, the reference relative velocity with respect to the target, and the relative acceleration with respect to the target. Has a function of obtaining the phase compensation amount so that the distances to the target at which the amplitude of the signal generated at the maximum is the same, and performing phase compensation of the received video signal.

Next, the processing operation of the signal processor 6K according to the tenth embodiment will be described with reference to FIG.
Similar to the reference relative speed / relative acceleration calculating means 20 according to the fourth embodiment, the reference relative speed / relative acceleration calculating means 20 calculates the relative acceleration between the target and the target according to the expressions (30) and (31). Calculate the reference relative speed.

The phase compensation unit 14F includes a relative acceleration a (hat) with respect to the target, which is an output of the reference relative speed / relative acceleration calculation unit 20, a reference relative speed v (hat) ₀ with respect to the target, and a relative distance / relative speed calculation unit 13. The distance to the target at which the amplitude of the signal generated by pulse-compressing each of the up-chirp received video signal and the down-chirp received video signal is maximized using the relative distance R ′ (n) to the target that is the output of _Are calculated in accordance with the equation (42) so as to be the same. Then, the phase compensation means 14F performs phase compensation of the received video signal V (n, m) according to the equation (43) using the phase compensation amount φ _cor (n, m), and the received video signal after phase compensation. V ′ _a (n, m) is output.

  Here, for the plus / minus sign and minus / plus sign, the upper code is selected when the received video signal to be compensated is an up-chirp received video signal, and the lower code is selected when the received video signal is a down-chirp received video signal.

As described above, the radar apparatus according to the tenth embodiment calculates the reference relative speed and the relative speed for calculating the reference relative speed with respect to the target and the relative acceleration with the target by the least square method from the speed measurement results for (number of pulses −1). The received video signal V (n, m) is phase-compensated in consideration of the relative distance between the acceleration calculating means 20 and the target, the reference relative speed with respect to the target, and the relative acceleration with the target, and the signal V ′ after phase compensation. _Since the phase compensation means 14F for outputting _a (n, m) is provided, it is possible to improve the target detection performance for a long-distance moving target having acceleration and to improve the relative speed measurement accuracy of the target.

Embodiment 11 FIG.
The radar apparatus according to the eleventh embodiment of the present invention is the same as the radar apparatus according to the fourth embodiment except for the signal processor 6L, and the other components are the same. To do. Then, as shown in FIG. 25, the signal processor 6L according to the eleventh embodiment includes a range correction unit 18C instead of the phase compensation unit 14 and the second pulse compression unit 15 of the signal processor 6D according to the fourth embodiment. And the acceleration compensation means 21 are different, and the other parts are the same, and the same parts are denoted by the same reference numerals and the description thereof is omitted.

The range correction means 18C according to the eleventh embodiment uses the reference relative speed with respect to the target, which is the output of the reference relative speed / relative acceleration calculation means 20, and the relative acceleration with the target to receive the up-chirp received video signal and the down-chirp received. Each of the video signals has a function of correcting the range of the signal generated by the pulse compression of the received video signal so that the distance to the target where the amplitude of the signal generated by the pulse compression is the same is the same.
The acceleration compensation means 21 according to the eleventh embodiment uses the relative acceleration with respect to the target, which is the output of the reference relative speed / relative acceleration calculation means 20, for the signal after the range correction, which is the output of the range correction means 18C. It has a function to perform acceleration compensation.

Next, the processing operation of the signal processor 6L according to the eleventh embodiment will be described with reference to FIG.
The range correction means 18C uses the reference relative speed v (hat) ₀ with respect to the target, which is the output of the reference relative speed / relative acceleration calculation means 20, and the relative acceleration a (hat) with the target, according to the equation (44). A range correction amount R _cor (n) is calculated.

Here, v (hat) (n) is calculated according to equation (29). The plus / minus sign is positive when range correction is performed on a signal generated by pulse compression of an up-chirp received video signal, and negative when it is performed on a signal generated by pulse compression of a down-chirp received video signal. Selected.
Then, the range correction unit 18C uses the calculated range correction amount R _cor (n) and the signal R _{V · Ex} (n, m _τ ) generated by pulse compression according to the equations (24) and (25). ) And the signal R _{V · Ex_cor} (n, m _τ ) after the range correction is output.

The acceleration compensation unit 21 uses the relative acceleration a (hat) with the target, which is the output of the reference relative velocity / relative acceleration calculation unit 20, to perform the range correction, which is the output of the range correction unit 18C, according to Expression (45). Acceleration compensation is performed on the signal R _{V · Ex_cor} (n, m _τ ) generated by pulse compression, and the signal R ′ _{V · Ex_cor} (n, m _τ ) after acceleration compensation is output.

  Thus, the radar apparatus according to the eleventh embodiment calculates the reference relative speed and the relative acceleration for calculating the reference relative speed and the relative acceleration with respect to the target by the least square method from the results of all the measured speeds ((number of pulses-1)). Reference relative speed with respect to the target so that the distance to the target where the amplitude of the signal generated by the pulse compression of each of the up-chirp received video signal and the down-chirp received video signal is the same is the same Range correction means 18C for performing range correction using the relative acceleration between the target and the target, and the relative acceleration between the target as the output of the reference relative speed / relative acceleration calculation means 20 and the range-corrected pulse compression. Acceleration compensation means for performing acceleration compensation to prevent degradation of target detection performance and relative speed measurement accuracy for moving target with acceleration Because with a 1, it is possible to improve the improvement and the target relative speed measurement accuracy of the target detection performance for moving target having an acceleration. Further, compared with the tenth embodiment, it is not necessary to perform the pulse compression twice, the configuration is simplified, and the processing time can be shortened.

Embodiment 12 FIG.
Since the radar apparatus according to the twelfth embodiment of the present invention is different from the radar apparatus according to the eleventh embodiment except for the signal processor 6M, the same parts are denoted by the same reference numerals, and the description thereof is omitted. To do. As shown in FIG. 27, the signal processor 6M according to the twelfth embodiment is different from the signal processor 6L according to the eleventh embodiment in the reference relative speed / relative acceleration calculating means 20B. Therefore, the same reference numerals are added to the same parts, and the description is omitted.

  The reference relative speed / relative acceleration calculating means 20B according to the twelfth embodiment receives the relative distances to a plurality of targets, which are the outputs of the relative distance / relative speed calculating means 13 for each pulse, and the total distance ((number of pulses -1) min) From the result, it has a function of calculating a reference relative speed with respect to the target and a relative acceleration with the target by the least square method.

Next, the processing operation of the signal processor 6M according to Embodiment 12 will be described with reference to FIG.
The reference relative speed / relative acceleration calculating means 20B calculates the relative distance between the reference relative speed and the target by the least square method from the relative distance to the target at the plurality of pulses that are the outputs of the relative distance / relative speed calculating means 13. Calculate acceleration.
The reference relative speed / relative acceleration calculating means 20B calculates the relative distance r ′ (n) based on the first distance measurement result R ′ (1) of the relative distance R ′ (n) to the target using the formula (46). Calculate according to

a (hat) is the relative acceleration with the target, t _n is the elapsed time from the first pulse transmission, v (hat) ₀ is the reference relative speed with the target, r (hat) ' ₁ is R' (1) Assuming the initial relative distance from the reference target, the distance r (hat) ′ _{n at} time t _n (= (n−1) T _pri ) is expressed by equation (47).

  The input of the least square method is obtained from the equation (48).

  Each matrix is set to Formula (49), Formula (50), Formula (51), and the inverse matrix is multiplied from the left side according to Formula (52) from the left side to obtain X, that is, the reference relative velocity and relative acceleration with respect to the target. obtain.

As described above, the radar apparatus according to the twelfth embodiment calculates the reference relative speed / relative acceleration with respect to the target by the least square method from the total distance measurement ((number of pulses-1)) result. Since the calculation means 20B is provided, it is possible to improve the target detection performance for the moving target having acceleration and to improve the relative speed measurement accuracy of the target.
Further, compared with the tenth embodiment, it is not necessary to perform the pulse compression twice, the configuration is simplified, and the processing time can be shortened.

Embodiment 13 FIG.
Since the radar apparatus according to the thirteenth embodiment of the present invention is different from the radar apparatus according to the fourth embodiment except for the signal processor 6N, the same parts are denoted by the same reference numerals and the description thereof is omitted. To do. Then, as shown in FIG. 29, the signal processor 6N according to the thirteenth embodiment replaces the reference relative speed / relative acceleration calculating means 20 of the signal processor 6D according to the fourth embodiment with a reference relative speed / relative acceleration. Since the calculation means 20B is different and the others are the same, the same portions are denoted by the same reference numerals and the description thereof is omitted.
The reference relative speed / relative acceleration calculating means 20B according to the thirteenth embodiment receives the relative distance from the target among a plurality of pulses as the output of the relative distance / relative speed calculating means 13, and calculates the total distance ((number of pulses -1) min) From the result, it has a function of calculating a reference relative speed with respect to the target and a relative acceleration with the target by the least square method.

Next, the processing operation of the signal processor 6N according to the thirteenth embodiment will be described with reference to FIG.
As with the reference relative speed / relative acceleration calculating means 20B according to the twelfth embodiment, the reference relative speed / relative acceleration calculating means 20B uses the equations (49), (50), and (51) as the respective matrices. Multiplying both sides by the inverse matrix according to (52) from the left side gives X, that is, the reference relative velocity and relative acceleration with respect to the target.

  As described above, the radar apparatus according to the thirteenth embodiment calculates the reference relative velocity with respect to the target and the relative acceleration with respect to the target by the least square method from the results of all the distance measurement ((number of pulses-1)). Since the relative acceleration calculation means 20B is provided, it is possible to improve the target detection performance for the moving target having acceleration and improve the relative speed measurement accuracy of the target.

Embodiment 14 FIG.
Since the radar apparatus according to the fourteenth embodiment of the present invention is different from the radar apparatus according to the tenth embodiment except for the signal processor 6P, the same parts are denoted by the same reference numerals and the description thereof is omitted. To do. As shown in FIG. 31, the signal processor 6P according to the fourteenth embodiment replaces the reference relative speed / relative acceleration calculating means 20 of the signal processor 6K according to the tenth embodiment with a reference relative speed / relative acceleration. Since the calculation means 20B is different and the others are the same, the same portions are denoted by the same reference numerals and the description thereof is omitted.
The reference relative velocity / relative acceleration calculating means 20B according to the fourteenth embodiment receives the relative distance from the target among a plurality of pulses as the output of the relative distance / relative speed calculating means 13, and calculates the total distance ((number of pulses -1) min) From the result, it has a function of calculating a reference relative speed with respect to the target and a relative acceleration with the target by the least square method.

Next, the processing operation of the signal processor 6P according to Embodiment 14 will be described with reference to FIG.
As with the reference relative speed / relative acceleration calculating means 20B according to the twelfth embodiment, the reference relative speed / relative acceleration calculating means 20B uses the equations (49), (50), and (51) as the respective matrices. Multiplying both sides by the inverse matrix according to (52) from the left side gives X, that is, the reference relative velocity and relative acceleration with respect to the target.

  As described above, the radar apparatus according to the fourteenth embodiment calculates the reference relative speed with respect to the target and the relative acceleration with respect to the target by the least square method from the results of the total distance measurement ((number of pulses−1)). Since the relative acceleration calculating means 20B is provided, it is possible to improve the target detection performance for a long-distance moving target having acceleration and improve the target relative speed measurement accuracy.

Embodiment 15 FIG.
Since the radar apparatus according to the fifteenth embodiment of the present invention is different from the radar apparatus according to the first embodiment except for the signal processor 6Q, the same parts are denoted by the same reference numerals and the description thereof is omitted. . As shown in FIG. 33, the signal processor 6Q according to the fifteenth embodiment has a PDI means 22 added to the signal processor 6 according to the first embodiment, and a discriminator instead of the distance measuring means 12. Since it is different in having the distance calculation means 23, and the others are the same, the same reference numerals are given to the same parts, and the description is omitted.

Next, the processing operation of the signal processor 6Q according to the fifteenth embodiment will be described with reference to FIG. However, the number of times of Post Detection Integration (hereinafter referred to as “PDI”) processing is set to two.
As shown in FIG. 35, in a low S / N environment, the amplitude of noise becomes larger than the amplitude of the signal generated by pulse compression, and the distance to the noise is erroneously calculated as the distance of the signal generated by pulse compression. there is a possibility. Therefore, the PDI means 22 performs PDI processing on the signal generated by pulse compression, and reduces the influence of noise.
A signal generated by pulse compression is input to the PDI means 22, and a reception signal obtained by transmitting and receiving a chirp-modulated transmission signal having the same slope is expressed by the equation (53). Accordingly, the PDI processing is performed, and the signal R _PDI (n, m _τ ) generated by the PDI processing is output. Here, N _PDI indicates the number of PDI processes.

When the A / D sampling frequency is low, as shown in FIG. 36, the distance measuring unit 12 does not necessarily have a signal generated by pulse compression, the distance to the target having a maximum amplitude, or a signal generated by PDI processing. It is not always the case that the distance to the target with the maximum amplitude is sampled.
In the distance measuring unit 12, it is necessary to increase the A / D sampling frequency in order to perform the distance calculation accuracy with high accuracy. Therefore, instead of the distance measuring means 12, the discrete distance calculating means 23 is for improving the distance calculation accuracy of a signal generated by pulse compression or a signal generated by PDI processing when the A / D sampling frequency is low. Discrete distance calculation processing is used.
This process extracts two adjacent signals with large amplitudes from the input signal and generates a value obtained by dividing the difference (Δ) between the amplitude values by the sum (Σ) of the two signals as a Δ / Σ value. To do. A distance correction amount R _{Δ / Σ_cor} corresponding to the generated Δ / Σ value is calculated based on the relationship between this Δ / Σ value, the previously determined Δ / Σ value, and the distance correction amount shown in FIG. The distance corrected by the distance correction amount _{RΔ / Σ_cor} is calculated as the distance to the target of the true input signal to obtain the distance. Hereinafter, specific processing contents of the discrete distance calculation processing will be described.

A signal R _PDI (n, m _τ ) generated by PDI processing is input to the discrete distance calculation means 23. Next, the discriminating distance calculation means 23 calculates the distance R _{Δ / Σ} and the sample points (R _i , R _i ) (i = a, b, c, d) in FIG. )), It is assumed that the true value of the distance is between two adjacent points (R _b , P _b ) and (R _c , P _c ) having a large signal amplitude, and the equation (54) Then, Δ / Σ value D is calculated. In the figure, circles indicate sample points, P _i indicates amplitude values for the sample points, and R _i indicates distances for the sample points.

Next, the distance correction amount R _{Δ / Σ_cor} is obtained from the relationship (= Δ / Σ curve) between the distance correction amount and the Δ / Σ value D calculated with high accuracy in advance as shown in FIG. A distance _{RΔ / Σ at} which the amplitude of the input signal is maximum is calculated by Expression (55). In the following description, the distance at which the amplitude is maximum is described as the peak distance.

The relative distance / relative speed calculating means 13 inputs R _{Δ / Σ} output from the discrete distance measuring means 23 as R _peak (n). Then, the relative distance / relative speed calculation means 13 calculates the relative distance to the target and the relative speed to the target according to the equations (14) and (15), as in the first embodiment.

As described above, since the radar apparatus according to the fifteenth embodiment includes the PDI means 22 that outputs the signal generated by the PDI processing, the noise is shifted by a distance that shows the maximum amplitude of the signal generated by the pulse compression. The distance to the target is not erroneously selected, and the distance measuring means 12 according to the first embodiment is provided instead of the distance measuring means 23, so that even with a low A / D sampling frequency, it is highly accurate. The peak distance of the signal generated by pulse compression can be calculated, the hardware scale is reduced, and the target detection performance in a lower S / N environment and the target relative speed measurement accuracy are improved. It becomes possible.
In the case of Embodiments 2 to 14, the same effect can be obtained by adding the PDI means 22 and using the discrete distance calculating means 23 instead of the distance measuring means 12.

Embodiment 16 FIG.
The radar apparatus according to the sixteenth embodiment of the present invention is different from the radar apparatus according to the fifteenth embodiment except for the signal processor 6R, and the other components are the same. . As shown in FIG. 38, the signal processor 6R according to the sixteenth embodiment includes the peak distance range calculating means 24 and the second discrete distance calculating means 23B in the signal processor 6Q according to the fifteenth embodiment. Are the same and the other parts are the same, the same reference numerals are given to the same parts, and the description thereof is omitted.

Next, the processing operation of the signal processor 6R according to the sixteenth embodiment will be described with reference to FIG. However, the number of PDI processes is set to two.
The peak distance range calculation means 24 receives the peak distance R _{Δ / Σ of} the signal generated by the PDI processing.
As shown in FIG. 40, the peak distance range calculation unit 24 calculates a preset peak distance around the peak distance R _{Δ / Σ} of the signal generated by the PDI processing input from the discrete distance calculation unit 23. The upper limit gate _up of the range for which the peak distance is calculated is calculated according to the equation (56) using the determined setting range gate. Further, the peak distance range calculating unit 24 calculates a set range gate for obtaining a preset peak distance around the peak distance R _{Δ / Σ} of the signal generated by the PDI processing input from the discrete distance calculating unit 23. The lower limit gate _down of the range for obtaining the peak distance is calculated according to the equation (57).

The second discrete distance calculation means 23B is generated by pulse compression of each pulse in accordance with the equations (54) and (55) within the range for obtaining the peak distance calculated by the equations (56) and (57). The peak distance R _peak (n, m _τ ) of the signal is calculated. Therefore, as shown in FIG. 40, by limiting the range for obtaining the peak distance, it is possible to prevent erroneous selection of noise and improve the peak distance calculation accuracy of the signal generated by pulse compression of each pulse. Become.

As described above, the radar apparatus according to the sixteenth embodiment includes the peak distance range calculating unit 24 that calculates the range for obtaining the peak distance, and the second discrete distance calculating unit 23B that calculates the peak distance within the peak distance range. As a result, it is possible to prevent noise from being selected by mistake, improve the peak distance calculation accuracy, improve the target detection performance in a lower S / N environment, and improve the target relative speed measurement accuracy. It becomes possible.
Also in the first to fourteenth embodiments, the PDI means 22 is added and the discrete distance calculating means 23, the peak distance range calculating means 24, and the second discrete distance calculating means 23B are used instead of the distance measuring means 12. As a result, the same effect can be obtained.

Embodiment 17. FIG.
The radar apparatus according to the seventeenth embodiment of the present invention is different from the radar apparatus according to the sixteenth embodiment in the transmitter 2B and the signal processor 6S, and the other parts are the same. Description is omitted. Then, as shown in FIG. 41, the signal processor 6S according to the seventeenth embodiment is different from the signal processor 6R according to the sixteenth embodiment in the PDI means 22B instead of the PDI means 22, and the relative distance / relative velocity calculation. Since the relative distance / relative speed calculating means 13B is different from the means 13 and the other parts are the same, the same parts are denoted by the same reference numerals and the description thereof is omitted.

Next, the processing operation of the signal processor 6S according to the seventeenth embodiment will be described with reference to FIGS. However, the number of PDI processes is set to two.
The transmitter 2B pulse-modulates the carrier signal for each PRI, and repeatedly performs up-chirp modulation and down-chirp modulation within the pulse for each of a plurality of continuous pulses to generate a transmission RF signal, and sends it to the transmission / reception switch 4 Output. For example, when the number of PDI processing times is set to 2, as shown in FIGS. 42 and 43, up-chirp modulation is performed on the first and second pulse-modulated signals, and the third time Down chirp modulation is performed on the fourth pulse modulated signal pulse, and up chirp modulation is performed on the fifth and sixth pulse modulated signal pulses. The transmitter 2B repeats this operation to generate a transmission RF signal and outputs it to the transmission / reception switch 4. In the following description, the case of the transmitter 2 is described as alternating transmission, and the case of the transmitter 2B is described as continuous transmission. As shown in FIG. 44, in the case of continuous transmission, the range walk amount of the peak distance between signals generated by pulse compression used for PDI processing is smaller than in the case of alternating transmission. Therefore, the peak distances of the signals generated by the pulse compression used for PDI processing are close to each other, the deterioration of the amplitude of the signal generated by PDI processing is reduced, and the calculation accuracy of the peak distance of the signal generated by PDI processing is reduced. Will improve.

The PDI means 22B receives a signal generated by pulse-compressing a reception signal obtained by continuously transmitting and receiving a chirp-modulated transmission signal with the same slope for each PRI.
The PDI means 22B performs PDI processing on a signal generated by pulse-compressing a reception signal obtained by transmitting and receiving a chirp-modulated transmission signal having the same slope according to the equation (58), and performs PDI processing. The signal R _PDI (n, m _τ ) generated by the above is output.

The relative distance / relative speed calculating means 13B calculates the relative distance and relative speed with respect to the target according to the equations (59) and (60), and outputs them to the phase compensating means. Here, n = 1, 2,..., Floor (N / N _PDI ) N _PDI and chirp (n) indicate whether the transmission RF signal is an up-chirp modulated signal or a down-chirp modulated signal, Chirp (n) is 1 for up-chirp modulation and chirp (n) is -1 for down-chirp modulation.

As described above, the radar apparatus according to the seventeenth embodiment, instead of the transmitter 2 of the sixteenth embodiment, performs pulse modulation on the carrier signal for each PRI and up-chirp-modulates the pulse alternately for each of a plurality of consecutive pulses. And a transmitter 2B that repeats down-chirp modulation to generate a transmission RF signal and outputs it to the transmission / reception switch 4, so that the peak distances of the signals generated by pulse compression used for PDI processing are close to each other The deterioration of the amplitude of the signal generated by the PDI process is reduced, and the peak distance calculation accuracy of the signal generated by the PDI process of the second discrete distance calculating unit 23B can be improved. Further, since the relative distance / relative speed calculating means 13B is provided instead of the relative distance / relative speed calculating means 13 of the fifteenth embodiment, the relative distance between the target and the target is determined in consideration of the number of PDI processes and the target movement. It is possible to calculate the relative speed, and it is possible to improve the target detection performance in a lower S / N environment and improve the target relative speed measurement accuracy.
Also in the case of the first to fifteenth embodiments, the PDI means 22B is added, the transmitter 2B instead of the transmitter 2 and the discrete distance calculating means 23 and the peak distance range calculating means 24 instead of the distance measuring means 12. By using the relative distance / relative speed calculating means 13B instead of the second discrete distance calculating means 23B and the relative distance / relative speed calculating means 13, the same effect can be obtained.

Embodiment 18 FIG.
The radar apparatus according to the eighteenth embodiment of the present invention is different from the radar apparatus according to the seventeenth embodiment in the transmitter 2C and the signal processor 6T, and is otherwise the same. Description is omitted. Then, as shown in FIG. 45, the signal processor 6T according to the eighteenth embodiment is different from the signal processor 6S according to the seventeenth embodiment in calculating the relative distance / relative speed instead of the relative distance / relative speed calculating means 13B. The difference is that the means 13C is provided, and the rest is the same, so the same parts are denoted by the same reference numerals and the description thereof is omitted.

Next, the processing operation of the signal processor 6T according to the eighteenth embodiment will be described with reference to FIG. However, the number of PDI processes is set to two.
The transmitter 2C performs pulse modulation on the carrier signal for each PRI and repeats up-chirp modulation within the pulse to generate a transmission RF signal and outputs it to the transmission / reception switch 4. As shown in FIG. 46, there is an advantage that the scale of the transmitter is reduced because of only up-chirp modulation.

  The relative distance / relative speed calculation means 13C calculates the relative distance and the relative speed with respect to the target in accordance with the equations (61) and (62), and outputs them to the phase compensation means 14. However, n = 1, 2,..., N−1. Further, since transmitter 2C in the eighteenth embodiment performs only up-chirp modulation, chirp (n) is 1.

As described above, the radar apparatus according to the eighteenth embodiment, instead of the transmitter 2B of the seventeenth embodiment, repeatedly modulates the carrier frequency for each PRI and up-chirp-modulates the pulse to transmit the RF signal. The transmitter 2C is generated and output to the transmission / reception switch 4 so that the size of the transmitter is reduced, and the relative distance / relative speed is replaced with the relative distance / relative speed calculating means 13B of the seventeenth embodiment. Since the calculating unit 13C is provided, it is possible to calculate the relative distance to the target and the relative speed with respect to the target in consideration of the target movement by chirp modulation with the same inclination. In addition, transmitter 2C of the eighteenth embodiment performs only up-chirp modulation, but the same effect can be obtained when only down-chirp modulation is performed.
Also in the first to fourteenth embodiments, the transmitter 2C instead of the transmitter 2 and the discrete distance calculating means 23, the peak distance range calculating means 24, and the second discrete distance calculating means instead of the distance measuring means 12. By using the relative distance / relative speed calculating means 13C instead of the relative distance / relative speed calculating means 13B, the same effect can be obtained.

It is a block diagram of the radar apparatus concerning Embodiment 1 of this invention. 6 is a diagram for explaining a processing operation of the signal processor 6 according to the first embodiment. FIG. It is explanatory drawing which shows the relative distance and speed calculation method with the conventional target using distance shift. It is explanatory drawing which shows the relative distance and speed calculation method with the target which considered the target movement between PRI using the distance shift in Embodiment 1 of this invention. It is explanatory drawing which shows the processing operation of pulse compression. It is a block diagram of the signal processor 6B concerning Embodiment 2 of this invention. FIG. 10 is a diagram for explaining a processing operation of a signal processor 6B according to the second embodiment. It is explanatory drawing which shows the processing operation | movement of a range correction | amendment. It is a block diagram of the signal processor 6C concerning Embodiment 3 of this invention. FIG. 10 is a diagram for explaining a processing operation of a signal processor 6C according to the third embodiment. It is a block diagram of signal processor 6D concerning Embodiment 4 of this invention. FIG. 10 is a diagram for explaining a processing operation of a signal processor 6D according to the fourth embodiment. It is a block diagram of the signal processor 6E concerning Embodiment 5 of this invention. FIG. 10 is a diagram for explaining a processing operation of a signal processor 6E according to the fifth embodiment. It is a block diagram of the signal processor 6F concerning Embodiment 6 of this invention. FIG. 10 is a diagram for explaining a processing operation of a signal processor 6F according to the sixth embodiment. It is a block diagram of the signal processor 6G concerning Embodiment 7 of this invention. FIG. 10 is a diagram for explaining a processing operation of a signal processor 6G according to the seventh embodiment. It is a block diagram of the signal processor 6H concerning Embodiment 8 of this invention. FIG. 10 is a diagram for explaining a processing operation of a signal processor 6H according to the eighth embodiment. It is a block diagram of the signal processor 6J concerning Embodiment 9 of this invention. FIG. 20 is a diagram for explaining a processing operation of a signal processor 6J according to the ninth embodiment. It is a block diagram of the signal processor 6K concerning Embodiment 10 of this invention. FIG. 20 is a diagram for explaining a processing operation of a signal processor 6K according to the tenth embodiment. It is a block diagram of the signal processor 6L concerning Embodiment 11 of this invention. FIG. 38 is a diagram for explaining a processing operation of the signal processor 6L according to the eleventh embodiment. It is a block diagram of the signal processor 6M concerning Embodiment 12 of this invention. FIG. 38 is a diagram for explaining a processing operation of a signal processor 6M according to the twelfth embodiment. It is a block diagram of the signal processor N concerning Embodiment 13 of this invention. FIG. 23 is a diagram for explaining a processing operation of a signal processor N according to the thirteenth embodiment. It is a block diagram of the signal processor 6P concerning Embodiment 14 of this invention. FIG. 25 is a diagram for explaining a processing operation of a signal processor 6P according to the fourteenth embodiment. It is a block diagram of the signal processor 6Q concerning Embodiment 15 of this invention. FIG. 38 is a diagram for explaining the processing operation of the signal processor 6Q according to the fifteenth embodiment (in the case of the number of PDI processing = 2 times). It is a figure for demonstrating the effect of a PDI process (when the number of PDI processes = 2 times). It is a figure for demonstrating the relationship between a sample point and a true peak position. It is a figure for demonstrating the relationship (= (DELTA) / (Sigma) curve) between distance correction amount and (DELTA) / (Sigma) value D. FIG. It is a block diagram of the radar apparatus concerning Embodiment 16 of this invention. FIG. 18 is a diagram for explaining a processing operation of a signal processor 6R according to the sixteenth embodiment (when the number of PDI processing times = 2). It is a figure for demonstrating the peak distance range calculation of a signal (when the number of times of PDI processing = 2). It is a block diagram of the radar apparatus concerning Embodiment 17 of this invention. FIG. 20 is a part of a diagram for explaining the processing operation of the signal processor 6S according to the seventeenth embodiment (in the case of the number of PDI processing = 2 times). FIG. 21 is a remaining part of the diagram for explaining the processing operation of the signal processor 6S according to the seventeenth embodiment. It is a figure for demonstrating the processing operation | movement of alternating transmission and continuous transmission. It is a block diagram of the radar apparatus concerning Embodiment 18 of this invention. FIG. 38 is a diagram for explaining the processing operation of the signal processor 6T according to the eighteenth embodiment (when the number of PDI processing times = 2).

Explanation of symbols

  1 antenna 2, 2, 2B, 2C transmitter, 3 chirp signal generator, 4 duplexer, 5 receiver, 6, 6B, 6C, 6D, 6E, 6F, 6G, 6H, 6J, 6K, 6L, 6M, 6N, 6P, 6Q, 6R, 6S, 6T Signal processor, 7 Display, 11 Pulse compression means, 12 Distance measurement means, 13, 13B, 13C Relative distance / relative speed calculation means, 14, 14B, 14C, 14D, 14E, 14F Phase compensation means, 15 Second pulse compression means, 16 Integration means, 17 Speed calculation means, 18, 18B, 18C Range correction means, 19, 19B Average relative speed calculation means, 20, 20B Reference relative speed / relative acceleration Calculation means, 21 Acceleration compensation means, 22 PDI means, 23, 23B Discrete distance calculation means, 24 Peak distance range calculation means.

Claims (15)

The carrier signal is pulse-modulated at a predetermined time interval, the transmission signal generated by alternately up-chirp modulation and down-chirp modulation in the pulse is radiated, and the transmission signal reflected and returned by the target is received as the reception signal. Radar equipment
Pulse compression means for pulse-compressing the received signal;
Ranging means for calculating a distance based on the intensity of the signal generated by the pulse compression,
Based on the strength of the signal generated by pulse compression of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal A relative distance / relative speed calculating means for calculating a relative speed with the target or a relative distance with the target from the difference in distance;
Compensating for the phase of the received signal, pulse-compress each of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal The phase compensation amount is calculated using the relative speed to the target or the relative speed to the target and the relative distance to the target so that the distance to the target of the signal generated by Compensating means for compensating the phase of the received signal using a quantity, and pulse-compressing the phase-compensated received signal;
Integrating means for adding a signal generated by pulse-compressing the phase-compensated received signal at a plurality of the time intervals;
A radar apparatus comprising: The carrier signal is pulse-modulated at a predetermined time interval, the transmission signal generated by alternately up-chirp modulation and down-chirp modulation in the pulse is radiated, and the transmission signal reflected and returned by the target is received as the reception signal. Radar equipment
Pulse compression means for pulse-compressing the received signal;
Ranging means for calculating a distance based on the intensity of the signal generated by the pulse compression,
Based on the strength of the signal generated by pulse compression of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal A relative distance / relative speed calculating means for calculating a relative speed with the target or a relative distance with the target from the difference in distance;
An average relative speed calculating means for calculating an average relative speed from a relative speed with respect to the target calculated at a plurality of the time intervals or a relative distance with the target;
Compensating for the phase of the received signal, pulse-compress each of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal The phase compensation amount is calculated using the average relative speed or the average relative speed and the relative distance to the target so that the distance to the target of the signal generated by Compensation means for compensating the phase of the received signal and pulse-compressing the phase-compensated received signal;
Integrating means for adding a signal generated by pulse-compressing the phase-compensated received signal at a plurality of the time intervals;
A radar apparatus comprising: The carrier signal is pulse-modulated at a predetermined time interval, the transmission signal generated by alternately up-chirp modulation and down-chirp modulation in the pulse is radiated, and the transmission signal reflected and returned by the target is received as the reception signal. Radar equipment
Pulse compression means for pulse-compressing the received signal;
Ranging means for calculating a distance based on the intensity of the signal generated by the pulse compression,
Based on the strength of the signal generated by pulse compression of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal A relative distance / relative speed calculating means for calculating a relative speed with the target or a relative distance with the target from the difference in distance;
A reference relative speed / relative acceleration calculating means for calculating a relative acceleration with respect to the target calculated from a plurality of the time intervals or a relative distance with the target and a reference relative speed with respect to the target;
Compensating for the phase of the received signal, pulse-compress each of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal The relative acceleration with the target and the reference relative speed with the target, or the relative distance with the target and the relative acceleration with the target and the target A compensation means for calculating a phase compensation amount using the reference relative speed, compensating the phase of the received signal using the phase compensation amount, and pulse compressing the phase compensated received signal;
Integrating means for adding a signal generated by pulse-compressing the phase-compensated received signal at a plurality of the time intervals;
A radar apparatus comprising: The carrier signal is pulse-modulated at a predetermined time interval, the transmission signal generated by alternately up-chirp modulation and down-chirp modulation in the pulse is radiated, and the transmission signal reflected and returned by the target is received as the reception signal. Radar equipment
Pulse compression means for pulse-compressing the received signal;
Ranging means for calculating a distance based on the intensity of the signal generated by the pulse compression,
Based on the strength of the signal generated by pulse compression of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal A relative distance / relative speed calculating means for calculating a relative speed with the target or a relative distance with the target from the difference in distance;
When the range of the signal generated by the pulse compression is corrected, the reception signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the reception signal obtained by transmitting / receiving the down-chirp modulated transmission signal The range correction amount is calculated using the relative speed with respect to the target so that the distance to the target of the signal generated by pulse compression of each signal is the same, and the pulse compression is performed using the range correction amount. Compensation means for correcting the range of the signal generated by
Integrating means for adding the range-corrected signals at a plurality of the time intervals;
A radar apparatus comprising: The carrier signal is pulse-modulated at a predetermined time interval, the transmission signal generated by alternately up-chirp modulation and down-chirp modulation in the pulse is radiated, and the transmission signal reflected and returned by the target is received as the reception signal. Radar equipment
Pulse compression means for pulse-compressing the received signal;
Ranging means for calculating a distance based on the intensity of the signal generated by the pulse compression,
Based on the strength of the signal generated by pulse compression of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal A relative distance / relative speed calculating means for calculating a relative speed with the target or a relative distance with the target from the difference in distance;
An average relative speed calculating means for calculating an average relative speed from a relative speed with respect to the target calculated at a plurality of the time intervals or a relative distance with the target;
When the range of the signal generated by the pulse compression is corrected, the reception signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the reception signal obtained by transmitting / receiving the down-chirp modulated transmission signal The range correction amount is calculated using the average relative speed so that the distance to the target of the signal generated by pulse compression of each signal is the same, and the pulse compression is performed using the range correction amount. Compensation means for correcting the range of the signal generated by
Integrating means for adding the range-corrected signals at a plurality of the time intervals;
A radar apparatus comprising: The carrier signal is pulse-modulated at a predetermined time interval, the transmission signal generated by alternately up-chirp modulation and down-chirp modulation in the pulse is radiated, and the transmission signal reflected and returned by the target is received as the reception signal. Radar equipment
Pulse compression means for pulse-compressing the received signal;
Ranging means for calculating a distance based on the intensity of the signal generated by the pulse compression,
Based on the strength of the signal generated by pulse compression of the received signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the received signal obtained by transmitting / receiving the down-chirp modulated transmission signal A relative distance / relative speed calculating means for calculating a relative speed with the target or a relative distance with the target from the difference in distance;
A reference relative speed / relative acceleration calculating means for calculating a relative acceleration with respect to the target calculated from a plurality of the time intervals or a relative distance with the target and a reference relative speed with respect to the target;
When the range of the signal generated by the pulse compression is corrected, the reception signal obtained by transmitting / receiving the up-chirp modulated transmission signal and the reception signal obtained by transmitting / receiving the down-chirp modulated transmission signal The range correction amount is calculated using the relative acceleration with respect to the target and the reference relative speed with respect to the target so that the distance to the target of the signal generated by pulse-compressing each signal becomes the same. Compensation means for correcting a range of a signal generated by performing the pulse compression using a correction amount;
Acceleration compensation means for performing acceleration compensation of the range-corrected signal using relative acceleration with respect to the target;
Integrating means for adding the acceleration-compensated signals at a plurality of the time intervals;
A radar apparatus comprising:   5. The radar apparatus according to claim 1, further comprising speed calculation means for calculating a target relative speed in consideration of a frequency return of an output signal of the integration means using a relative speed with respect to the target. .   6. The radar according to claim 2, further comprising speed calculating means for calculating a target relative speed in consideration of a frequency return of an output signal of the integrating means using an average relative speed with respect to the target. apparatus.   7. The radar according to claim 3, further comprising: a speed calculating unit that calculates a target relative speed in consideration of a return of a frequency of an output signal of the integrating unit using a reference relative speed with respect to the target. apparatus.   The relative distance / relative velocity calculation means pulse-compresses each of a reception signal obtained by transmitting / receiving the up-chirp modulated transmission signal and a reception signal obtained by transmitting / receiving the down-chirp modulated transmission signal. 10. The relative speed with respect to the target or the relative distance with respect to the target is calculated in consideration of the difference in distance based on the intensity of the signal generated by this and the target movement at the time interval. The radar device according to any one of the above.   Instead of the distance measuring means, a value obtained by dividing the difference between the amplitude values of adjacent two signals having high intensities by the sum of the two signals from the signal generated by the pulse compression is generated as a Δ / Σ value, and the Δ Based on the / Σ value and the relationship between the previously obtained Δ / Σ value and the distance correction amount, the distance correction amount corresponding to the generated Δ / Σ value is calculated, and the distance corrected by the distance correction amount is calculated. The radar apparatus according to claim 1, further comprising: a discrete distance calculating unit that performs the determination.   PDI means for performing PDI processing on a signal generated by pulse-compressing a reception signal obtained by transmitting and receiving a transmission signal that is chirp modulated with the same inclination between the pulse compression means and the distance measurement means The radar apparatus according to claim 1, further comprising:   A peak distance range calculation unit that calculates a range for obtaining a peak distance of a signal generated by pulse compression of each pulse using a distance obtained from a signal generated by PDI processing. 12. A radar apparatus according to item 12.   The above-mentioned transmission in which the carrier signal is pulse-modulated at a predetermined time interval, and a transmission signal generated by up-chirp modulation and down-chirp modulation is alternately emitted for each successive multiple pulses and reflected back at the target. The radar device according to any one of claims 1 to 13, wherein the signal is received as a received signal.   The carrier signal is pulse-modulated at a predetermined time interval, the transmission signal generated by continuously up-chirp modulation or down-chirp modulation in the pulse is radiated, and the transmission signal reflected by the target and returned is used as the reception signal. The radar device according to claim 1, wherein the radar device receives the radar device.

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