JP2009162613A - Radar system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acquire a radar system capable of measuring a target angle by monopulse angle measurement even under the condition of the presence of disturbing waves which disturb a main beam, reducing the amount of computation, and avoid cost increases. <P>SOLUTION: The radar system is provided with: a transmitter/receiver for transmitting beam signals and receiving reflected signals from a target; a monopulse angle measurement means for measuring an angle in the arrival direction of the target; and a signal processing part 10A for removing disturbing waves which are contained in reception signals and which disturb the main beam or interfering waves which interfere with the main beam. The signal processing part 10A is provided with a main robe protection means 44 for protecting the main beam and a sidelobe disturbance reduction means 40 for removing disturbing waves from the reception signal. The sidelobe disturbance reduction means 40 includes a blocking filter 47 which operates with the main robe protection means 44 for preventing excess reductions of a main lobe component. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention transmits a beam signal, receives a reflected wave from the target with an array antenna, measures the direction of arrival of the target by estimating the target signal included in the received signal, and based on the angle measurement result, The present invention relates to a radar apparatus that determines the directivity direction of a transmission beam.

  In general, in ship-borne radar and ground radar, when the interference of electromagnetic waves from the main beam direction of the reflected wave including the target signal is affected, the radar can no longer be used due to the influence of jamming. To achieve this, the so-called burn-through mode is used to concentrate the energy (number of pulse hits) in the target direction and improve the ratio of the signal power from the target to the interference power (hereinafter referred to as S / J ratio). Target detection. However, when the burn-through mode is applied, there is a problem that the tracking performance with respect to the target is deteriorated because the angle of the arrival direction of the target is not usually measured.

  In addition, in order to perform target angle measurement in an environment where there is an interference wave from the main beam direction, the normal monopulse angle measurement method cannot be used, so it is possible to switch to super-resolution angle measurement and perform target angle measurement. Many.

  As for super-resolution angle measurement, a high-resolution algorithm called a MUSIC (Multiple Signal Classification) method is conventionally known (for example, see Non-Patent Document 1). Further, ESPRIT method having super resolution performance is also known (for example, see Non-Patent Document 2), and application of the maximum likelihood estimation method to monopulse radar is also proposed (for example, see Non-Patent Document 3). . However, these angle measurement methods have a higher calculation amount than the monopulse angle measurement method, and therefore, when mounted on the apparatus, it is necessary to mount a processor capable of high-speed processing.

  On the other hand, the side lobe interference suppressing means using the adaptive array (AA) and the main lobe interference removing means using the main lobe canceller (MLC) are used in combination, and by using these suppressing means together, the main lobe component is excessive. In order to prevent suppression, a signal processing unit that can realize monopulse angle measurement even in a main beam interference environment by adding a main lobe protection means having a main lobe maintenance (MLM) function to the side lobe interference suppression means. A radar apparatus has been proposed (for example, see Non-Patent Document 4).

The schematic configuration of the conventional radar apparatus described in Non-Patent Document 4 will be described below with reference to the block configuration diagram of FIG. 6 and the functional block diagrams of FIGS. 7 to 9.
In FIG. 6, the radar device is a transmitter that outputs a transmission frequency setting value and a transmission timing trigger, a frequency oscillator 2 that generates a continuous wave based on the transmission frequency setting value, and a transmission unit based on the transmission timing trigger. A transmitter 3 that outputs a transmission pulse obtained by pulse-modulating a wave, a phase shifter 4 that performs a phase operation on the transmission pulse based on a beam forming weight setting value (described later), a transmission / reception switcher 5 that switches transmission and reception, And an array antenna 6 for transmitting a transmission pulse input via the transmission / reception switch 5 in the air.

  The array antenna 6 composed of a plurality of array antennas functions not only as a transmission array antenna but also as a reception array antenna, and a reflected wave (transmission wave) reflected by a target (not shown) whose angle is to be measured ( Target signal) and all incoming waves such as clutter reflected waves and jamming waves.

  The radar apparatus shown in FIG. 6 includes, as a receiving unit, an array antenna 6, a receiver 7 that converts an incoming wave (received signal) input via the transmission / reception switch 5 into an intermediate frequency signal, and a phase detector 8. A signal processing unit 10, a monopulse angle measuring unit 11, and a transmission beam pointing direction calculating unit 12.

The phase detector 8 performs A / D conversion and phase detection on the intermediate frequency signal from the receiver 7 and outputs M received signals X0 (n) to XM-1 (n) in the baseband.
The signal processing unit 10 extracts desired parameters based on the received signals X0 (n) to XM-1 (n) converted into digital signals by the phase detector 8, and the monopulse angle measuring means 11 includes a signal processing unit A target angle measurement value is obtained based on the parameters extracted in step 10.
The transmission beam pointing direction calculation means 12 calculates and outputs the next transmission beam pointing direction and beam forming weight setting values for the target as the setting values for the phase shifter 4 of the transmission unit based on the target angle measurement values.

FIG. 7 is a functional block diagram showing a specific configuration of the signal processing unit 10 in FIG.
In FIG. 7, the signal processing unit 10 includes a side lobe interference suppression unit 20, a main lobe interference removal unit 21, an interference wave correlation matrix estimation unit 22, a side lobe interference suppression weight estimation unit 23, and a main lobe protection unit 24. And.

The sidelobe interference suppression unit 20 uses AA to remove interference waves coming from other than the main beam direction from the reception signals X0 (n) to XM-1 (n).
Further, the main lobe disturbance removing means 21 removes the interference wave coming from the main beam direction from the received signals ΔΔ, ΔEl, ΔAz, Σ from the side lobe disturbance suppressing means 20 using MLC.

The interference wave correlation matrix estimation means 22 estimates the arrival direction of the interference wave from other than the main beam direction by calculating a correlation matrix related to the target received signal.
The sidelobe interference suppression weight estimation means 23 calculates a weighting coefficient W ^ ΣΣ for canceling the signal in the direction of arrival of the estimated interference wave.
The main lobe protection means 24 calculates a weighting coefficient for compensating for the deterioration on the signal in the main beam direction by the side lobe interference suppression operation.

FIG. 8 is a functional block diagram showing a specific configuration of the side lobe disturbance suppressing means 20 in FIG.
In FIG. 8, the sidelobe interference suppression means 20 includes difference beam calculation means 30 for extracting the difference beam rΔe from the received signals X0 (n) to XM-1 (n), and received signals X0 (n) to XM-1 ( n) Sum beam calculation means 31 for extracting the sum beam rΣe from n), weighting means 32, 33 using the difference beam rΔe as an input signal, and weighting means 34, 35 using the sum beam rΣe as an input signal.

The weighting means 32, 33, 34, and 35 use AA to output beams ΔΔ, ΔE1, ΔAz, and Σ in which sidelobe interference waves are canceled.
Further, the output beams from the respective weighting means 32, 33, 34, and 35 are converted into parameters used by the main lobe disturbance removing means 21 located at the subsequent stage of the side lobe disturbance suppressing means 20.

FIG. 9 is a functional block diagram showing a specific configuration example of the weighting means 32, 33, 34, 35, and typically shows the weighting means 35 related to the sum beam calculation means 31.
In FIG. 9, the weighting means 35 outputs the output signals of N FIR (Finite Impulse Response) filters 36 (0) to 36 (N-1) and FIR filters 36 (0) to 36 (N-1). And a summer 37 for adding.
The FIR filters 36 (0) to 36 (N-1) output N sum beams rΣe (0) to rΣe (N-1) based on the M received signals X0 (n) to XM-1 (n). Input signal.

On the other hand, the main lobe protection means 24 (see FIGS. 7 and 8) related to the side lobe interference suppression weight estimation means 23 includes the following main lobe protection operations (1) to (5).
(1) Reconstruction operation of covariance matrix using subspace constraint,
(2) Main lobe holding operation using diagonal loading,
(3) An operation of extracting only influential signals (only signals exceeding a predetermined threshold) based on eigenvalue analysis,
(4) Main lobe interference wave filtering operation,
(5) An operation of calculating a blocking filter coefficient described below using the MUSIC method (Non-Patent Document 1).

  However, the main lobe protection operation (= blocking filter coefficient calculation operation) of (1) to (5), which is a feature of the radar apparatus described in Non-Patent Document 4, is an adaptive process (adaptive weighting) with a large amount of calculation. Therefore, it is necessary to mount a processor capable of high-speed processing when mounting on a radar apparatus, which causes an increase in the cost of the apparatus.

  Further, as a technique for realizing the sidelobe canceller (SLC), a technique using generalized sidelobe cancellation (GSC) has been proposed in addition to the technique using the AA (see, for example, Non-Patent Document 5).

In the technique using GSC, a blocking filter (or a blocking matrix) is provided for blocking mixing in the auxiliary channel in order to prevent the desired wave component from mixing into the auxiliary channel and canceling.
However, effective knowledge about the shape and characteristics of the blocking filter has not been obtained, and as a result, the method using GSC has not reached the practical level.

R. O. Schidt, “Multiple Emitter Location and Signal Parameter Estimate”, IEEE Trans. on Antennas and Propagation, vol. AP-34, no. 3 (Mar. 1986) R. Roy, T .; Kailath, “ESPRIT—Estimation of Signal Parameters Via Rotational Innovation Techniques”, IEEE Trans. on Acoustics, Speech, and signal processing, vol. 37, no. 7 (Jully 1989) I. Ziskind, M.M. Wax, “Maximum Likelihood Localization of Multiple Sources by Alternating Project”, IEEE Trans. on Acoustics, Speech, and signal processing, vol. 36, no. 10 (Oct. 1988) Kai-Bor Yu, D.C. J. et al. Murrow, “Adaptive Digital Beamforming for Angle Estimating in Jamming”, IEEE Trans. on aerospace and electronic systems vol. 37, no. 2 (April 2001) L. J. et al. Griffiths, C.I. W. Jim, “An Alternative Approach to Linearly Constrained Adaptive Beamforming”, IEEE Trans. on Antennas and Propagation, vol. AP-30, no. 1 (Jan. 1986)

  In the conventional radar apparatus, in any case of Non-Patent Documents 1 to 4, since the amount of calculation is large, it is necessary to mount a processor capable of high-speed processing, and there is a problem that the cost of the entire apparatus is increased. The method using GSC as in Non-Patent Document 5 also has a problem that it has not reached the practical stage.

  The present invention has been made to solve the above-described problems, and reduces the amount of computation while enabling target angle measurement by monopulse angle measurement even under the condition that there is an interfering wave that interferes with the main beam. It is an object of the present invention to obtain a practical radar device that avoids an increase in cost.

  A radar apparatus according to the present invention includes an array antenna that transmits and receives signals, a transmitter that transmits a beam signal having a predetermined frequency from the array antenna, and a receiver that receives a reflected signal from a target based on the beam signal as a received signal from the array antenna. And monopulse angle measuring means for measuring the direction of arrival of the target based on the received signal, and monopulse angle measuring means for removing the interference wave interfering with the main beam or the main beam included in the received signal. In a radar apparatus including a signal processing unit for enabling angle measurement by the signal processing unit, the signal processing unit includes main lobe protection means for protecting the main beam, and sidelobe interference for removing the interference wave or interference wave from the received signal. Suppression means, side lobe disturbance suppression means in cooperation with the main lobe protection means, Excessive suppression of Inrobu component is intended to include blocking filter to prevent the adverse effects on MLC processing.

  According to the present invention, the cost is increased by realizing a method with a small amount of calculation while further adding a main lobe protection function to a combination of AA (adaptive array) and MLC (main lobe canceller). Thus, a practical radar device can be obtained.

Embodiment 1 FIG.
In Embodiment 1 of the present invention, GSC (Generalized Sidelobe Canceller) is used instead of AA in the conventional apparatus as the sidelobe interference suppression function. Hereinafter, the GSC according to Embodiment 1 of the present invention is referred to as a “monopulse beam constrained GSC”.
In the first embodiment of the present invention, as a method for realizing a “blocking filter” for realizing the main lobe protection function, the arrival direction of the target signal (the main beam direction of the received wave) is the transmission beam direction of the radar antenna. To obtain a plurality of eigenvectors spanning a subspace in which a steering vector within the transmission beam width exists corresponding to the transmission beam direction of the radar antenna, and calculate a blocking matrix using these eigenvectors as beam weights, This is applied as a main beam protection matrix.
Since this method can realize the blocking matrix calculation using non-adaptive eigenvector calculation, this makes it possible to achieve a simpler and less computation amount than the AA method based on adaptive processing in the conventional device, and is equivalent to the adaptive method. Realize the functions and performance.

Hereinafter, the first embodiment of the present invention will be described in detail with reference to FIGS.
The schematic configuration of the radar apparatus according to Embodiment 1 of the present invention is as shown in FIG. 6, and only the functions of the signal processing unit are partially different.
FIG. 1 is a functional block diagram showing a specific configuration of a signal processing unit 10A of a radar apparatus according to Embodiment 1 of the present invention. Components similar to those described above (see FIG. 7) are denoted by the same reference numerals. Detailed description is omitted.

In FIG. 1, the signal processing unit 10A includes a side lobe interference suppression unit 40, a main lobe interference removal unit 41, an interference wave correlation matrix estimation unit 42, a side lobe interference suppression weight estimation unit 43, and a main lobe protection unit 44. And a main beam correlation matrix calculation means 45.
Each means 40-44 in signal processing part 10A is equivalent to each above-mentioned means 20-24 (refer to Drawing 7), respectively.

The interference wave correlation matrix estimation means 42 generates a covariance matrix R as an interference wave correlation matrix, and inputs the covariance matrix R to the sidelobe interference wave weight estimation means 43.
The main beam correlation matrix calculation means 45 generates a main beam correlation matrix RMB corresponding to a plurality of eigenvectors extending in a partial space where a steering vector corresponding to the side lobe exists, and the main beam correlation matrix RMB is supplied to the main lobe protection means 44. input.

The main lobe protection means 44 obtains a plurality of eigenvectors based on the main beam correlation matrix RMB, calculates blocking filter coefficients using the plurality of eigenvectors as beam weights, and sets the blocking filter coefficients as blocking filter 47 and sidelobe interference wave weights. Input to the estimation means 43.
The side lobe interference wave weight estimation unit 43 generates a side lobe interference wave weight W ^ ΣΣ based on the covariance matrix R and the blocking filter coefficient, and the side lobe interference wave weight W ^ ΣΣ to the side lobe interference suppression unit 43. input.

  The specific operation of the main beam correlation matrix calculating means 45 is disclosed in known documents (for example, Takahashi, Suwa, Inaba, “Target estimation method using subspace structure of steering vector within array antenna main beam width”, electronic information communication) Academic Journal B, Vol. J89-B, No. 7, 2006).

FIG. 2 is a functional block diagram showing a specific configuration of the sidelobe interference suppressing means 40 in FIG.
In FIG. 2, the side lobe disturbance suppressing means 40 includes a multiplier 46 that multiplies the reception signals X0 (n) to XM-1 (n) by a predetermined coefficient, and the reception signals X0 (n) to XM-1 (n). A blocking filter 47 that extracts only the side lobe component, a difference beam calculation means 48 and a sum beam calculation means 49 that calculate the difference beam rΔe and the sum beam rΣe from the output signal of the multiplier 46, and a difference from the output signal of the blocking filter 47 Difference beam calculation means 50 and sum beam calculation means 51 for calculating the beam r′Δe and the sum beam r′Σe, a summing device 52 for adding the difference beam rΔe, a summing device 53 for adding the sum beam rΣe, and a received signal Adders 54 to 57 that output beam signals ΔΔ, ΔE1, ΔAz, and Σ obtained by dividing the sidelobe component from the output of each calculation means 48 to 51. And a weighting means 58 to 65 for outputting a cancel beams sidelobe interference wave based on the signal.

The difference beam calculation means 48 and 50 correspond to the difference beam calculation means 30 described above (see FIG. 8), and the sum beam calculation means 49 and 51 correspond to the aforementioned sum beam calculation means 31.
The weighting means 58 to 61 correspond to the weighting means 32 to 35, respectively. Similarly, the weighting means 62 to 65 correspond to the weighting means 32 to 35, respectively.
Each of the weighting means 58 to 65 is realized by AA as described above.

FIG. 3 is a functional block diagram showing a specific configuration example of the weighting means 58 to 65, and typically shows the weighting means 65 related to the sum beam calculation means 51.
In FIG. 3, the weighting means 65 is a summing unit 67 for adding the output signals of N FIR filters 66 (0) to 66 (N-1) and FIR filters 66 (0) to 66 (N-1). And.

The FIR filters 66 (0) to 66 (N-1) are N sum beams r'Σe (0) to r'Σe (N based on M received signals X0 (n) to XM-1 (n). -1) is an input signal.
The FIR filters 66 (0) to 66 (N-1) correspond to the FIR filters 36 (0) to 36 (N-1) described above (see FIG. 9), and the totalizer 67 corresponds to the above-described totalizer 37. It corresponds.

  As described above, the radar apparatus according to Embodiment 1 of the present invention includes an array antenna 6 (see FIG. 6) that transmits and receives signals, a transmitter 3 that transmits a beam signal of a predetermined frequency from the array antenna 6, and a beam. A receiver 7 that receives a reflected signal from a target based on the signal as a received signal from the array antenna 6 and a monopulse angle measuring device that measures the direction of arrival of the target based on the received signals X0 (n) to XM-1 (n). The monopulse angle measuring unit 11 can measure the angle by removing the interference wave interfering with the main beam included in the received signal X0 (n) to XM-1 (n) or the main beam. A signal processing unit 10A.

  The signal processing unit 10A includes a main lobe protection unit 44 that protects the main beam, and a side lobe interference suppression unit 40 that removes an interference wave or interference wave from the received signal. The side lobe interference suppression unit 40 includes the main lobe protection unit 40. In cooperation with the means 44, the sidelobe interference suppressing means 40 includes a blocking filter 47 for preventing excessive suppression to the main lobe component and adversely affecting subsequent MLC processing.

The signal processing unit 10A includes a main beam correlation matrix calculation unit 45. The main beam correlation matrix calculation unit 45 includes a steering vector within the transmission beam width corresponding to the transmission beam direction of the radar antenna. A main beam correlation matrix RMB corresponding to a plurality of eigenvectors spanning the partial space is generated for the space, and the main beam correlation matrix RMB is input to the main lobe protection means 44.
The main lobe protection means 44 calculates a plurality of eigenvectors based on the main beam correlation matrix RMB, calculates blocking filter coefficients using the plurality of eigenvectors as beam weights, and inputs the blocking filter coefficients to the blocking filter 47.

  Further, the sidelobe interference suppression unit 40 includes a sum beam calculation unit 50 and a difference beam calculation unit 51 that cooperate with the blocking filter 47, and a sum beam and a difference beam calculated by the sum beam calculation unit 50 and the difference beam calculation unit 51. Weighting means 62 to 65 for performing a weighting operation on the signal and outputting a beam in which the sidelobe interference wave is canceled.

  As described above, the main beam correlation matrix calculating unit 45 is provided in the signal processing unit 10A, and the main lobe protection unit 44 includes a plurality of blocking filter coefficients (a plurality of subspaces in which a steering vector corresponding to the transmission beam direction of the radar antenna exists). And a blocking filter 47 is provided in the sidelobe interference suppression means 40 cooperating with the main lobe protection means 44, and the auxiliary channel (unconstrained component) system of the monopulse beam constrained GSC is provided. A blocking filter coefficient is used as the main lobe protection matrix as the main lobe protection matrix.

As a result, the main beam component is almost orthogonal to each eigenvector constituting the blocking matrix, so that it is canceled and the main lobe component does not leak from the subsequent stage of the blocking filter 47. Therefore, even if the side lobe cancel operation is executed by the adders 54 to 57, the main lobe component is satisfactorily held without being excessively canceled (suppressed).
As a result, the main beam interference wave can be prevented from being mixed into the auxiliary channel, and the monopulse beam-constrained GSC can selectively suppress only the sidelobe interference.

The operation of the main lobe protection means 44 is only to obtain a plurality of eigenvectors based on the main beam correlation matrix RMB generated by the main beam correlation matrix calculation means 45, so that blocking processing is not performed without performing an adaptive process with a large amount of calculation. Filter coefficients can be obtained, and the amount of calculation can be greatly reduced.
Therefore, a processor capable of high-speed processing is not required and the cost is not increased.

Embodiment 2. FIG.
In the first embodiment (FIG. 2), the blocking filter 47 is provided on the input side of each calculation means 48 to 51. However, as shown in FIG. 4, the blocking filter 47 is provided on the output side of each calculation means 70, 71. Blocking matrices 72 to 75 corresponding to 47 may be provided.
FIG. 4 is a functional block diagram showing the side lobe disturbance suppressing means 40B in the signal processing unit according to Embodiment 2 of the present invention.

In FIG. 4, the same components as those described above (see FIG. 2) are denoted by the same reference numerals as those described above, or “B” after the symbols, and detailed description thereof is omitted.
In this case, the sidelobe interference suppression unit 40B includes the difference beam calculation unit 70 and the sum beam calculation unit 71 that receive the received signals X0 (n) to XM-1 (n) as input signals, and the difference from the difference beam calculation unit 70. Blocking matrices 72 and 73 having the beam rΔe as an input signal, blocking matrices 74 and 75 having the sum beam rΣe from the sum beam calculation means 71 as an input signal, adders 54 to 57 and weighting means 58 to 65.

FIG. 5 is a functional block diagram showing the mutual relationship between the blocking matrix 75 and the weighting means 61 and 65 related to the sum beam calculating means 71.
In FIG. 5, the blocking matrix (BΣΣ) 75 is based on the N sum beams r′Σe (0) to r′Σe (N−1) and has a required D order (maximum (N−1) order). Are output to the weighting means 65.

  As shown in FIG. 4 and FIG. 5, even when the blocking matrices 72 to 75 cooperating with the main lobe protection means 44B are arranged in the subsequent stage of the difference beam 70 and the sum beam calculation means 71, The same effect is obtained.

It is a functional block diagram which shows the signal processing part of the radar apparatus which concerns on Embodiment 1 of this invention. It is a functional block diagram which shows the specific structure of the side lobe disturbance suppression means in FIG. It is a functional block diagram which shows the specific structural example of the weighting means in FIG. It is a functional block diagram which shows the specific structure of the side lobe disturbance suppression means in the signal processing part which concerns on Embodiment 2 of this invention. It is a functional block diagram which shows the mutual relationship of the blocking matrix in FIG. 4, and a weighting means. It is a block block diagram which shows a general radar apparatus roughly. It is a functional block diagram which shows specifically the signal processing part of the conventional radar apparatus. It is a functional block diagram which shows concretely the side lobe disturbance suppression means in the conventional signal processing part. It is a functional block diagram which shows concretely the weighting means in the side lobe disturbance suppression means of the conventional signal processing part.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Controller, 2 Frequency oscillator, 3 Transmitter, 4 Phase shifter, 5 Transmission / reception switching device, 6 Array antenna, 7 Receiver, 8 Phase detector, 10A Signal processing part, 11 Monopulse angle measuring means, 12 Transmission beam direction Direction calculation means, 40, 40B Side lobe interference suppression means, 41 Main lobe interference removal means, 42 Interference wave correlation matrix estimation means, 43, 43B Side lobe interference suppression weight estimation means, 44, 44B Main lobe protection means, 45 Main beam Correlation matrix calculation means, 47 Blocking filter, 48, 50, 70 Difference beam calculation means, 49, 51, 71 Sum beam calculation means, 54-57 Adder, 58-65 Weighting means, 72-75 Blocking matrix.

Claims (4)

An array antenna for transmitting and receiving signals;
A transmitter for transmitting a beam signal of a predetermined frequency from the array antenna;
A receiver that receives a reflected signal from a target based on the beam signal as a received signal from the array antenna;
Monopulse angle measuring means for measuring the direction of arrival of the target based on the received signal;
A radar apparatus comprising: a signal processing unit for removing an interfering wave that interferes with a main beam included in the received signal or an interfering wave that interferes with the main beam to enable angle measurement by the monopulse angle measuring means In
The signal processing unit
Main lobe protection means for protecting the main beam;
Sidelobe interference suppression means for removing the interference wave or the interference wave from the received signal,
The radar apparatus according to claim 1, wherein the side lobe interference suppressing means includes a blocking filter for preventing excessive suppression of main lobe components in cooperation with the main lobe protection means. The signal processing unit includes a main beam correlation matrix calculation unit,
The main beam correlation matrix calculation means generates a main beam correlation matrix corresponding to a plurality of eigenvectors extending the partial space for a partial space where a steering vector corresponding to the sidelobe component exists,
The main lobe protection means calculates the plurality of eigenvectors based on the main beam correlation matrix, calculates a blocking filter coefficient using the plurality of eigenvectors as beam weights, and inputs the blocking filter coefficient to the blocking filter. The radar apparatus according to claim 1. The sidelobe interference suppression means is
Sum beam calculation means and difference beam calculation means in cooperation with the blocking filter;
And a weighting unit that performs a weighting operation on the sum beam and the difference beam calculated by the sum beam calculation unit and the difference beam calculation unit, and outputs a beam in which a sidelobe interference wave is canceled. The radar apparatus according to claim 1 or 2.   The radar device according to any one of claims 1 to 3, wherein the blocking filter includes a blocking matrix.

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