JP5289193B2 - Radar signal processing apparatus and unwanted wave suppression method - Google Patents

Description

  The present invention relates to a radar signal processing apparatus and an unnecessary wave suppression method capable of receiving a desired signal by suppressing unnecessary reception waves.

  In general, a radar signal processing device forms a directional antenna pattern, suppresses an unnecessary wave received by a side lobe by an unnecessary wave suppression device (SLC: Sidelobe Canceller), and acquires a target (desired) signal. In addition to SLC, this type of radar signal processing apparatus is provided with a main antenna that forms a directional antenna pattern and an auxiliary antenna that forms a pattern having an antenna gain larger than the side lobe of the antenna pattern in the main antenna. Provided (see, for example, Patent Document 1). The SLC performs weight control on the radar reflected signal received by the auxiliary antenna, thereby performing pattern formation so that the reception sensitivity in the arrival direction of the unnecessary wave becomes zero as a result and suppressing the unnecessary wave.

  By the way, when the SLC is to be implemented in a digital signal processor (DSP) in a radar signal processing device, the Wiener Hop equation is used for the data sequence of radar reflected signals acquired by the main antenna and the auxiliary antenna. A method using an SMI (Sample Matrix Inversion) algorithm that directly calculates an adaptive weight in (see, for example, Non-Patent Documents 1 and 2). However, in the case of SLC implemented by software using the SMI method, in order to cope with a time-varying system in which the antenna rotates at high speed (the arrival direction of unnecessary waves changes with time), the average weight of the sample data Therefore, SMI must be performed by dividing the data so that is an instantaneous weight from one direction. Therefore, there is a problem that unnecessary wave suppression performance deteriorates because the number of data samples is reduced. In addition, since it is necessary to repeat many SMI operations by dividing data, there is a problem that the calculation load increases and the hardware scale increases.

  Here, it is also conceivable to implement software implementation of SLC by a method using an LMS (Least Mean Squares) algorithm or an RLS (Recursive Least Squares) algorithm that sequentially calculates adaptive weights by feedback sequential processing. Since the LMS algorithm and the RLS algorithm perform feedback sequential processing, it is possible to satisfy weight tracking performance adapted to a time-varying system in which an antenna rotates at high speed. However, there is a problem that a finite convergence time is required until the adaptive weight is calculated for the feedback sequential processing, and a blind time (a state where the target cannot be seen due to unnecessary wave residual power) occurs in the radar reception distance.

JP 2006-267036 A

Simon Haykin, "Adaptive Filter Theory", Prentice Hall, P. 104 Brennan L.E. and Reede I.S., "Theory of Adaptive Radar", IEEE Trans. On Aerospace and Electronic Systems, Vol. AES-9, No. 2, March 1973, P. 237-252

  As described above, when the SLC of the radar signal processing device whose antenna rotates at high speed is to be implemented by software, when the SMI algorithm is used, the unnecessary wave suppression performance deteriorates due to the adaptive weight tracking of the time-varying system, When the LMS and RLS algorithms are used, there is a problem that blind time occurs even if deterioration of unnecessary wave suppression performance due to adaptive weight tracking can be avoided.

  The present invention has been made for the above circumstances, and its purpose is to suppress deterioration of unnecessary wave suppression performance due to tracking of a time-varying system by SLC implemented by software, eliminate the existence of convergence time, and use a radar antenna that rotates at high speed. An object of the present invention is to provide a radar signal processing apparatus and an unnecessary wave suppression method capable of suppressing unnecessary waves contained in a received radar signal.

  In order to achieve the above object, a radar signal processing apparatus according to the present invention receives a plurality of antennas that receive radar reflected signals independently from each other and a plurality of radar reflected signals received by the plurality of antennas. A plurality of reception processing units, and a received detection signal of one specific system among the reception detection signals of the plurality of systems received and detected by the plurality of reception processing units, other than the specific system subjected to weight control. A signal processing unit that suppresses unnecessary wave components contained in the received detection signal of the specific system by subtracting the received detection signal, and the signal processing unit uses an SMI (Sample Matrix Inversion) algorithm The weight calculation for calculating the weight of the received detection signals other than the specific system based on the data of the preset head region of each of the received detection signals of the plurality of systems And the weight calculated by the weight calculating means is used as an initial weight, and the weight control of the received detection signal other than the specific system is performed by feedback sequential processing, and the weight control is performed from the received detection signal of the specific system Unnecessary wave suppression means for subtracting received detection signals other than the specific system.

  The unnecessary wave suppression method according to the present invention includes a plurality of antennas that receive radar reflection signals independently of each other, and a plurality of reception processes that receive and detect each of a plurality of radar reflection signals received by the plurality of antennas. And a reception detection signal other than the specific system subjected to weight control, from a reception detection signal of one specific system among the reception detection signals of the plurality of systems received and detected by the plurality of reception processing units An unnecessary wave suppression method used in a radar signal processing apparatus including a signal processing unit that suppresses an unnecessary wave component included in the received detection signal of the specific system, and includes an SMI (Sample Matrix Inversion) algorithm. Utilizing the specific system based on the data of the head region set in advance for each of the reception detection signals of the plurality of systems received and detected by the plurality of reception processing units The weight of the received detection signal other than the specific system is calculated, the weight of the received detection signal other than the specific system is controlled by feedback sequential processing using the calculated weight as the initial weight, and the weight control is performed from the received detection signal of the specific system The received detection signal of other than the specific system to which is applied is subtracted.

  In the radar signal processing apparatus and the unwanted wave suppression method configured as described above, an initial weight is calculated using an SMI algorithm, and feedback sequential processing is performed using this initial weight. As a result, even when the antenna rotates at high speed, it is possible to avoid unnecessary wave suppression performance deterioration due to adaptive weight tracking by updating the weight by sequential processing and to eliminate the blind time until the weight converges. Become.

  According to the present invention, software-implemented SLC suppresses unnecessary wave suppression performance deterioration due to adaptive weight tracking of a time-varying system, and unnecessary waves included in a radar reflected signal received by a radar antenna that rotates at high speed. It is possible to provide a radar signal processing apparatus and an unnecessary wave suppression method that can be suppressed.

It is a block diagram which shows the function structure of the radar signal processing apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the function structure of the signal processing part shown in FIG. It is a block diagram which shows typically the process in the equalization part shown in FIG. It is a block diagram which shows the function structure of the LMS process part shown in FIG. It is a block diagram which shows the function structure of the weight process part shown in FIG. It is a flowchart which shows the process of SLC shown in FIG. It is the figure which showed typically the process in the SMI process part and LMS process part which are shown in FIG. It is a block diagram which shows the function structure of the signal processing part which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows typically the process in the pulse compression part of FIG.

  Embodiments of a radar signal processing apparatus according to the present invention will be described below in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a block diagram showing a functional configuration of a radar signal processing apparatus according to the first embodiment of the present invention. The radar signal processing apparatus shown in FIG. 1 includes a main antenna 10, a main receiver 20, auxiliary antennas 30-1 to 30-n, auxiliary receivers 40-1 to 40-n, and a signal processing unit 50.

  The main antenna 10 includes antenna elements 11-1 to 11-n, receiving modules 12-1 to 12-n, and a receiving power feeding circuit 13. The main antenna 10 rotates at high speed in the directing direction by controlling the phases of the antenna elements 11-1 to 11-n from the outside. The main antenna 10 receives the radar reflection signal reflected from the target by the antenna elements 11-1 to 11-n and supplies the received radar reflection signal to the main receiver 20. Further, when calculating the equalization coefficients of equalization units 53-2 to 53-n in the signal processing unit 50, which will be described later, the main antenna 10 has a fixed directivity direction and a wider band than the reception band of the radar reflected signal. A width noise signal is sprayed. The main antenna 10 supplies the received noise signal to the main receiver 20.

  The main receiver 20 receives and detects the received radar reflected signal or noise signal, and supplies it to the signal processing unit 50. Specifically, the main receiver 20 frequency-converts the received radar reflection signal or noise signal into an intermediate frequency band signal, performs analog-digital conversion, and then supplies the signal to the signal processing unit 50 as a digital signal of the main channel. .

  The auxiliary antennas 30-1 to 30-n include antenna elements 31-11 to 311-1n... 31-n1 to 31-nn, reception modules 32-11 to 212-1n. 33-1 to 33-n. The auxiliary antennas 30-1 to 30-n receive radar reflected signals by the antenna elements 31-11 to 31-1n... 31-n1 to 31-nn, and receive the received radar reflected signals as auxiliary receivers 40-1 to 40-40. -Supply to -n. The auxiliary antennas 30-1 to 30-n are sprayed with noise signals when calculating equalization coefficients of equalization units 53-2 to 53-n in the signal processing unit 50 described later. The auxiliary antennas 30-1 to 30-n supply the received noise signals to the auxiliary receivers 40-1 to 40-n.

  The auxiliary receivers 40-1 to 40-n receive and detect the received radar reflection signal or noise signal, and supply the received signal to the signal processing unit 50. Specifically, the auxiliary receivers 40-1 to 40-n frequency-convert the received radar reflected signal or noise signal into an intermediate frequency band signal, perform analog-to-digital conversion, and then output the signal as a digital signal of the auxiliary channel. It supplies to the processing part 50.

  The signal processing unit 50 is configured by, for example, a DSP (Digital Signal Processor), and implements the functional configuration shown in the block diagram of FIG. 2 by executing an application program. Of course, a CPU (Central Processing Unit) made of a microprocessor can also be used. That is, the signal processing unit 50 includes a received data temporary storage unit 51, switching units 52-1 to 52- (n + 1), equalization units 53-2 to 53- (n + 1), an equalization coefficient calculation unit 54, an MTI (Moving Target indicator) 55 and SLC 56 functions are realized.

  The received data temporary storage unit 51 temporarily stores the received digital signals of the main channel and auxiliary channel, and outputs the digital signals of each channel to the switching units 52-1 to 52- (n + 1), respectively. The switching units 52-1 to 52- (n + 1) selectively switch the output system of the digital signal. When calculating the equalization coefficients of the equalization units 53-2 to 53- (n + 1), The signal is derived to the equalization coefficient calculator 54. When the equalization coefficients of the equalization units 53-2 to 53- (n + 1) are not adjusted, the switching unit 52-1 derives the digital signal of the main channel to the MTI 55, and the switching units 52-2 to 52- (n + 1) derives the digital signal of the auxiliary channel to equalization units 53-2 to 53- (n + 1).

  The equalization units 53-2 to 53- (n + 1) receive the digital signal of the auxiliary channel, and adjust the amplitude and phase of the digital signal of the auxiliary channel based on the equalization coefficient calculated by the equalization coefficient calculation unit 54. To match the frequency characteristics with the digital signal of the main channel. FIG. 3 is a block diagram schematically showing processing in the equalization unit 53-2 among the equalization units 53-2 to 53- (n + 1). The equalization unit 53-2 performs an FFT (Fast Fourier Transform) process 531 on the received digital signal of the auxiliary channel, and blocks the digital signal in units of data having a preset size. The equalization unit 53-2 multiplies the data block blocked by the FFT process 531 by the coefficient obtained by performing the FFT process on the equalization coefficient calculated by the equalization coefficient calculation unit 54, and performs IFFT (Inverse Fast Fourier). (Transform) After processing 532, the data is output to the MTI 55.

  The equalization coefficient calculation unit 54 calculates equalization coefficients of the equalization units 53-2 to 53- (n + 1) based on digital signals derived from the noise signals of the main channel and the auxiliary channel. For example, the equalization coefficient calculation unit 54 estimates the correlation matrix and the correlation vector from the sampled digital signals of the main channel and the auxiliary channel using the SMI algorithm, and performs equalization by adaptive equalization using the Wiener Hop equation. The equalization coefficient optimal for the units 53-2 to 53- (n + 1) is directly calculated. In calculating the equalization coefficient, an LMS algorithm, an RLS algorithm, or the like can be used.

  The MTI 55 suppresses clutter contained in the digital signal of the main channel and the digital signal of the auxiliary channel output from the equalization units 53-2 to 53-(n + 1), and supplies the digital signal after suppression to the SLC 56.

  The SLC 56 includes an SMI processing unit 561 and an LMS processing unit 562. By performing weight control, the SLC 56 performs pattern formation so that the reception sensitivity in the direction of unwanted wave arrival is less than or equal to the receiver noise. Repress.

  The SMI processing unit 561 receives the digital signals of the main channel and auxiliary channel output from the MTI 55. The SMI processing unit 561 uses, for example, four pieces of data (for example, from the antenna rotation speed and wavelength conditions) that are successively input from the head data among the digital signals of the main channel and auxiliary channel from the MTI 55 using the SMI algorithm. The adaptive weight Wi is calculated based on the time that can be regarded as data in one direction. Then, the SMI processing unit 561 outputs the calculated adaptive weight Wi to the LMS processing unit 562.

For example, the SMI processing unit 561 has four systems when four auxiliary antennas 30-1 to 30-4 are installed in the radar signal processing apparatus and digital signals of four auxiliary channels are supplied to the signal processing unit 50. For example, a covariance matrix M and a cross-correlation vector R shown below are calculated from, for example, four data strings V in each of the auxiliary channels and N data strings Vm in the main channel, and an adaptive weight Wi is calculated from these values. To do.

Note that E [] indicates an ensemble average, and * indicates a complex conjugate. here,

The adaptive weight vector Wi is

Is calculated. T represents transposition and μ represents an arbitrary constant.

  The LMS processing unit 562 receives the main channel and auxiliary channel digital signals output from the MTI 55. The LMS processing unit 562 uses the adaptive weight Wi calculated by the SMI processing unit 561 as an initial weight, and calculates a weight based on all data in the received digital signals of the main channel and the auxiliary channel using the LMS algorithm. . Then, the unnecessary weight included in the radar reflected signal received by the main antenna 10 is suppressed by multiplying the calculated weight by the digital signal of the auxiliary channel and subtracting it from the digital signal of the main channel.

FIG. 4 is a block diagram showing a functional configuration of the LMS processing unit 562 shown in FIG. The LMS processing unit 562 implements the weight processing units 5621-1 to 5621-n by using the LMS algorithm. The weight processing units 5621-1 to 5621-n calculate a weight for the digital signal of each auxiliary channel by feedback sequential processing, and multiply the digital signal of each auxiliary channel by the calculated weight. FIG. 5 is a block diagram illustrating a functional configuration of the weight processing unit 5621-1 illustrated in FIG. 4. Here, when the input digital signal of the auxiliary channel is a (t) and the feedback signal is c (t), the differential equation for the weight w (t) is

It becomes. Note that k represents a loop gain, and * represents a complex conjugate. Also, assuming that the input digital signal of the main channel is b (t), the feedback signal c (t) is

(7) can be expressed as

The steady solution w (∞) of the weight w (t) is

Is calculated. At this time, the transit solution and the time constant of the weight w (t) are

It is expressed. Note that w (0) is an initial value of the weight w (t). The weight processing unit 5621-1 substitutes wi1 which is one component of Wi calculated by the SMI processing unit 561 into w (0), thereby shortening the convergence time of the weight w (t).

  Next, the operation in the above configuration will be described. FIG. 6 is a flowchart showing the processing of the SLC 56 according to the first embodiment of the present invention. FIG. 7 is a diagram schematically illustrating processing in the SMI processing unit 561 and the LMS processing unit 562.

  When clutter suppression is performed by the MTI 55, the SLC 56 extracts, for example, four consecutive data from the main channel and auxiliary channel signals subjected to clutter suppression by the SMI processing unit 561, and based on the extracted data. Then, the adaptive weight Wi is calculated (step 61). Subsequently, the SLC 56 performs weight control using the adaptive weight Wi calculated by the SMI processing unit 561 as an initial weight by the LMS processing unit 562, and suppresses interference signals (step 62).

  As described above, the radar signal processing apparatus according to the first embodiment calculates adaptive weights based on, for example, four pieces of data extracted from the main channel and auxiliary channel signals using the SMI algorithm. Then, the radar signal processing device performs weight control on the signal of the auxiliary channel using the LMS algorithm with the adaptive weight calculated by the SMI algorithm as an initial weight, and unnecessary waves included in the radar reflected signal received by the main antenna. To suppress.

  Here, each of, for example, four consecutive data extracted when calculating the adaptive weight by the SMI algorithm is much smaller than the number of data acquired while the main antenna 10 rotates once at high speed. It is a number. In other words, the radar signal processing apparatus can calculate the adaptive weight by assuming that the radar reflection signal comes from a fixed direction by calculating the adaptive weight based on, for example, four data in each of the main channel and the auxiliary channel. It becomes. Further, since the radar signal processing apparatus performs an inverse matrix operation by the SMI algorithm based on, for example, four continuous data in the digital signals of the main channel and the auxiliary channel, the calculation amount can be suppressed. Further, since the radar signal processing apparatus uses the adaptive weight calculated by the SMI algorithm as the initial weight, it is possible to eliminate the occurrence of the blind time that has always occurred when performing the LMS algorithm. As a result, even when the main antenna 10 rotates at high speed, deterioration of unnecessary wave suppression performance due to adaptive weight tracking is avoided by updating the weights through sequential processing, and blind time until the weights converge is eliminated. It becomes possible.

  Therefore, the radar signal processing apparatus according to the present invention suppresses unnecessary wave suppression performance deterioration due to adaptive weight tracking in a time-varying system by software-implemented SLC, and receives a radar reflected signal received by a radar antenna that rotates at high speed. Can suppress unwanted waves.

  In the radar signal processing apparatus according to the first embodiment, equalization processing of the digital signal of the main channel and the digital signal of the auxiliary channel is realized by software processing in the signal processing unit 50. For this reason, since it is not necessary to install an equalizer independently of the signal processing unit 50, the hardware scale can be reduced, and the radar signal processing apparatus can be reduced in size and cost.

  Furthermore, in the radar signal processing apparatus according to the first embodiment, the equalization coefficient calculation unit 54 uses the equalization unit 53-2 by blowing noise signals to the main antenna 10 and the auxiliary antennas 30-1 to 30-n. The equalization coefficient in .about.53-n is calculated. Conventionally, in order to increase the correlation between the main channel and the auxiliary channel, a measure for matching frequency characteristics (including group delay) with an equalizer using a tapped delay line (TDL) has been implemented. Specifically, while stepping the frequency of a CW signal (sin wave having a constant frequency) that is coherent to the radar device at a constant interval, the signal is sampled for each frequency to obtain a data string. The equalization coefficient was calculated based on the data string. However, such a frequency sampling method has a problem that it takes time to obtain data for obtaining the equalization coefficient. On the other hand, in the radar signal processing device according to the present invention, it is possible to calculate the equalization coefficient only by blowing a noise signal, so that the time required for calculating the equalization coefficient of the equalization unit is reduced. be able to.

[Second Embodiment]
FIG. 8 is a block diagram showing a functional configuration of the signal processing unit 60 according to the second embodiment of the present invention. In FIG. 8, parts that are the same as those in FIG. 2 are given the same reference numerals, and only different parts will be described here. In the present embodiment, the main antenna 10 and the auxiliary antennas 30-1 to 30-n receive reflected pulses that are pulse-modulated radar reflected signals, and the main receiver 20 and the auxiliary receivers 40-1 to 40-40. -N performs reception detection of the received reflected pulse.

  The signal processing unit 60 illustrated in FIG. 8 realizes the functions of the received data temporary storage unit 51, the switching units 52-1 to 52- (n + 1), the pulse compression unit 57, the equalization coefficient calculation unit 54, the MTI 55, and the SLC 56. The pulse compression unit 57 performs pulse compression on the digital signals of the main channel and the auxiliary channel derived from the switching units 52-1 to 52- (n + 1), and the equalization coefficient calculated by the equalization coefficient calculation unit 54. Based on the above, the frequency characteristics of the digital signal of the main channel and the digital signal of the auxiliary channel are matched. FIG. 9 is a block diagram schematically showing processing in the pulse compression unit 57 of FIG. The pulse compression unit 57 performs FFT processing 571-1 on the received digital signal of the main channel, and blocks this digital signal in units of data having a preset size. The pulse compression unit 57 multiplies the data block blocked by the FFT process 571-1 by the coefficient obtained by performing the FFT process on the pulse compression coefficient corresponding to the pulse modulation of the reflected pulse received by the main antenna 10, and the IFFT After processing 572-1, the data is output to the MTI 55. Further, the pulse compression unit 57 performs FFT processing 571-2 to 571-(n + 1) on the received digital signal of the auxiliary channel, and blocks these digital signals in units of data having a preset size. To do. The pulse compression unit 57 applies a pulse compression coefficient corresponding to the pulse modulation of the reflected pulse received by the auxiliary antennas 30-1 to 30-n to the data block blocked by the FFT processing 571-2 to 571- (n + 1). Is multiplied by the coefficient that has been subjected to the FFT process and the coefficient that has been subjected to the FFT process, and the IFFT process 572-2 to 572- (n + 1). Output to MTI55.

  As described above, in the radar signal processing device according to the second embodiment, equalization processing is performed on the digital signal of the auxiliary channel simultaneously with the processing of the pulse compression unit 57. As a result, the FFT processing and IFFT processing in the pulse compression unit 57 can be used for equalization processing, so that it is not necessary to perform FFT processing and IFFT processing for equalization processing. Therefore, it is possible to suppress the calculation load in the signal processing unit 60.

[Other Embodiments]
The present invention is not limited to the above embodiments. For example, in each of the above-described embodiments, the case where the SMI processing unit 561 calculates the adaptive weight Wi based on, for example, four pieces of data that are continuously input from the head data among the digital signals of the main channel and the auxiliary channel will be described. However, the number of data is not limited to four from the top data. For example, the number of data may be four or more as long as the incoming signal received by the main antenna rotating at high speed can be regarded as being from a fixed direction.

  Further, although cases have been described with the above embodiments where the SLC 56 includes the LMS processing unit 562, the RLS processing unit that performs weight control by feedback sequential processing using the RLS algorithm can be similarly implemented. Further, the LMS processing unit 562 can be implemented in the same manner even when unnecessary waves are suppressed by the Gram Schmitt method.

  Furthermore, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 10 ... Main antenna 11-1 to 11-n ... Antenna element 12-1 to 12-n ... Reception module 13 ... Feeding circuit 20 ... Main receiver 30-1 to 30-n ... Auxiliary antenna 31-11 to 31-1n ,..., 31-n1 to 31-nn... Antenna elements 32-11 to 212-1n,..., 32-n1 to 32-nn, receiving modules 33-1 to 33-n, and feeding circuits 40-1 to 40-n. ... Auxiliary receivers 50, 60 ... Signal processing unit 51 ... Reception data temporary storage units 52-1 to 52- (n + 1) ... Switching units 53-2 to 53- (n + 1) ... Equalization unit 54 ... Equalization coefficient calculation unit 55 ... MTI
56 ... SLC
561... SMI processing unit 562... LMS processing units 5621-1 to 5621-n... Wait processing unit 57... Pulse compression units 571-1 to 571-(n + 1).

Claims (10)

A plurality of antennas for receiving radar reflection signals independently of each other;
A plurality of reception processing units for receiving and detecting each of a plurality of radar reflection signals received by the plurality of antennas;
By subtracting reception detection signals other than the specific system subjected to weight control from the reception detection signals of one specific system among the reception detection signals of the plurality of systems received and detected by the plurality of reception processing units. A signal processing unit that suppresses unnecessary wave components included in the received detection signal of the specific system,
The signal processing unit
Performing FFT (Fast Fourier Transform) processing on reception detection signals other than the specific system among a plurality of reception detection signals from the plurality of reception processing units to block in units of data of a preset size, Each block data is multiplied by an equalization coefficient multiplied by a coefficient subjected to FFT processing, and IFFT (Inverse Fast Fourier Transform) processing is performed on a plurality of data blocks multiplied by the equalization coefficient. Equalizing means for matching frequency characteristics of a plurality of received detection signals of a plurality of systems from the plurality of reception processing units;
By using an SMI (Sample Matrix Inversion) algorithm, a predetermined number of reception detection signals of the specific system and a reception number of reception detection signals supplied from the equalization means are input in succession . Weight calculating means for calculating a weight of a received detection signal other than the specific system based on the data;
Using the weight calculated by the weight calculation means as an initial weight, weight control of the received detection signal other than the specific system is performed by feedback sequential processing, and the specific system is subjected to the weight control from the received detection signal of the specific system A radar signal processing apparatus comprising: unnecessary wave suppression means for subtracting a received detection signal other than the above.   The radar signal processing apparatus according to claim 1, wherein the unnecessary wave suppression unit performs the weight control using an LMS (Least Mean Squares) algorithm.   The radar signal processing apparatus according to claim 1, wherein the unnecessary wave suppression unit performs the weight control using an RLS (Recursive Least Squares) algorithm. When the plurality of antennas receive a noise signal having a wider bandwidth than the reception band,
The radar signal processing apparatus according to claim 1, wherein the signal processing unit further includes an equalization coefficient calculation unit that calculates the equalization coefficient based on noise signals received by the plurality of antennas. A plurality of antennas for receiving radar reflection signals independently of each other;
A plurality of reception processing units for receiving and detecting each of a plurality of radar reflection signals received by the plurality of antennas;
By subtracting reception detection signals other than the specific system subjected to weight control from the reception detection signals of one specific system among the reception detection signals of the plurality of systems received and detected by the plurality of reception processing units. A signal processing unit that suppresses unnecessary wave components included in the received detection signal of the specific system,
The signal processing unit
Data blocks of the received detection signals of the plurality of systems by performing FFT (Fast Fourier Transform) processing on the received detection signals of a plurality of systems from the plurality of reception processing units to block in units of data having a preset size. Among them, the data block of the received detection signal of the specific system is multiplied by a coefficient obtained by performing FFT processing on a pulse compression coefficient preset for each system, and among the data blocks of the received detection signal of the plurality of systems, The pulse compression coefficient is obtained by multiplying the data block of the received detection signal other than the specific system by the coefficient obtained by performing FFT processing on the pulse compression coefficient preset for each system, and the coefficient obtained by performing FFT processing on the equalization coefficient. Alternatively, IFFT (Inverse Fast Fourier Transform) processing is performed on a plurality of data blocks obtained by multiplying the pulse compression coefficient and the equalization coefficient. Performing pulse compression on the plurality of received detection signals from the plurality of reception processing units and matching the frequency characteristics of the received detection signals of the plurality of systems, and
Using an SMI (Sample Matrix Inversion) algorithm, receiving signals other than the specific system are received based on a preset number of data continuously input from the head data of each received detection signal supplied from the pulse compression means. Weight calculating means for calculating the weight of the detection signal;
Using the weight calculated by the weight calculation means as an initial weight, weight control of the received detection signal other than the specific system is performed by feedback sequential processing, and the specific system is subjected to the weight control from the received detection signal of the specific system A radar signal processing apparatus comprising: unnecessary wave suppression means for subtracting a received detection signal other than the above.   6. The radar signal processing apparatus according to claim 5, wherein the unnecessary wave suppression means performs the weight control using an LMS (Least Mean Squares) algorithm.   6. The radar signal processing apparatus according to claim 5, wherein the unnecessary wave suppressing means performs the weight control using an RLS (Recursive Least Squares) algorithm. When the plurality of antennas receive a noise signal having a wider bandwidth than the reception band,
The radar signal processing apparatus according to claim 5, wherein the signal processing unit further includes an equalization coefficient calculation unit that calculates the equalization coefficient based on noise signals received by the plurality of antennas. A plurality of antennas for receiving radar reflection signals independently of each other, a plurality of reception processing units for receiving and detecting each of a plurality of systems of radar reflection signals received by the plurality of antennas, and reception detection by the plurality of reception processing units The received detection signal of the specific system is subtracted from the received detection signal of one specific system among the received detection signals of the specific system, and the received detection signal other than the specific system subjected to weight control is subtracted from the received detection signal of the specific system. An unnecessary wave suppression method used in a radar signal processing apparatus including a signal processing unit that suppresses an included unnecessary wave component,
Performing FFT (Fast Fourier Transform) processing on reception detection signals other than the specific system among a plurality of reception detection signals from the plurality of reception processing units to block in units of data of a preset size,
For each of the blocked data, an equalization coefficient is multiplied by a coefficient subjected to FFT processing,
By performing IFFT (Inverse Fast Fourier Transform) processing on a plurality of data blocks multiplied by the equalization coefficient, the frequency characteristics of a plurality of received detection signals from the plurality of reception processing units are matched,
Using an SMI (Sample Matrix Inversion) algorithm, based on a predetermined number of data continuously received from the head data of the received detection signal of the specific system and the received detection signal matching the frequency characteristics, Calculate the weight of the received detection signal other than the specific system,
Using the calculated weight as an initial weight, weight control of a received detection signal other than the specific system is performed by feedback sequential processing, and reception detection other than the specific system subjected to the weight control from the received detection signal of the specific system A method for suppressing unnecessary waves, characterized by subtracting a signal. A plurality of antennas for receiving radar reflection signals independently of each other, a plurality of reception processing units for receiving and detecting each of a plurality of systems of radar reflection signals received by the plurality of antennas, and reception detection by the plurality of reception processing units The received detection signal of the specific system is subtracted from the received detection signal of one specific system among the received detection signals of the specific system, and the received detection signal other than the specific system subjected to weight control is subtracted from the received detection signal of the specific system. An unnecessary wave suppression method used in a radar signal processing apparatus including a signal processing unit that suppresses an included unnecessary wave component,
Performing FFT (Fast Fourier Transform) processing on a plurality of received detection signals of a plurality of systems from the plurality of reception processing units to block in units of data of a preset size,
Of the data blocks of the received detection signals of the plurality of systems, the data block of the received detection signals of the specific system is multiplied by a coefficient obtained by performing FFT processing on a pulse compression coefficient preset for each system,
Among the data blocks of the received detection signals of the plurality of systems, the data block of the received detection signals other than the specific system, the coefficient obtained by performing FFT processing on the pulse compression coefficient preset for each system, and the equalization coefficient Multiplying the FFT processed coefficient,
By performing IFFT (Inverse Fast Fourier Transform) processing on the pulse compression coefficient or a plurality of data blocks obtained by multiplying the pulse compression coefficient and the equalization coefficient, a plurality of data received from the plurality of reception processing units While performing pulse compression on the received detection signal of the system, matching the frequency characteristics of the received detection signal of the plurality of systems,
Using the SMI (Sample Matrix Inversion) algorithm, the weight of the received detection signal other than the specific system is calculated based on a preset number of data continuously received from the head data of each of the pulse-compressed received detection signals. And
Using the calculated weight as an initial weight, weight control of a received detection signal other than the specific system is performed by feedback sequential processing, and reception detection other than the specific system subjected to the weight control from the received detection signal of the specific system A method for suppressing unnecessary waves, characterized by subtracting a signal.

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