Signal processing device, radar device and signal processing method

1. A signal processing device, comprising:

an azimuth estimation unit configured to estimate an arrival azimuth of a radio wave based on a reception signal of a plurality of antennas;

an estimated reception signal calculation unit configured to calculate an estimated reception signal based on an estimation result of the arrival azimuth, for comparison with the reception signal;

a residual signal calculation unit configured to calculate a residual signal which is a difference between the reception signal and the estimated reception signal; and

a determination unit configured to determine whether the estimation result of the arrival azimuth is correct based on the residual signal,

wherein the determination unit determines whether the estimation result of the arrival azimuth is correct by comparing a power value calculated based on the reception signal with a residual power value calculated from the residual signal, and

wherein the determination unit:

determines that the estimation result of the arrival azimuth is correct when formula (1) is satisfied in the comparing between the power value and the residual power value:

power value>residual power value+α  (1),

where α is a predetermined offset value; and

determines that the estimation result of the arrival azimuth is incorrect when formula (2) is satisfied in the comparing between the power value and the residual power value:

power value≤residual power value+α  (2).

2. The signal processing device according to claim 1 ,

wherein the power value is an azimuth power calculated based on a complex amplitude of the radio wave coming from the estimated arrival azimuth.

3. The signal processing device according to claim 2 ,

wherein the plurality of antennas are a plurality of virtual antennas based on a combination of a plurality of transmission antennas and a plurality of reception antennas.

4. The signal processing device according to claim 1 ,

wherein the power value is a power value derived based on a power spectrum obtained by performing Fourier transform on the reception signal.

5. The signal processing device according to claim 4 ,

wherein the plurality of antennas are a plurality of virtual antennas based on a combination of a plurality of transmission antennas and a plurality of reception antennas.

6. The signal processing device according to claim 1 ,

wherein the plurality of antennas are a plurality of virtual antennas based on a combination of a plurality of transmission antennas and a plurality of reception antennas.

7. A radar device, comprising:

the signal processing device according to claim 1 ; and

the plurality of antennas configured to acquire the reception signal.

8. A signal processing method, comprising:

estimating an arrival azimuth of a radio wave based on a reception signal of a plurality of antennas;

calculating an estimated reception signal based on an estimation result of the arrival azimuth, for comparison with the reception signal;

calculating a residual signal which is a difference between the reception signal and the estimated reception signal; and

determining whether the estimation result of the arrival azimuth is correct based on the residual signal,

wherein the determining determines whether the estimation result of the arrival azimuth is correct by comparing a power value calculated based on the reception signal with a residual power value calculated from the residual signal, and

wherein the determining:

determines that the estimation result of the arrival azimuth is correct when formula (1) is satisfied in the comparing between the power value and the residual power value:

power value>residual power value+α  (1),

where a is a predetermined offset value; and

determines that the estimation result of the arrival azimuth is incorrect when formula (2) is satisfied in the comparing between the power value and the residual power value:

power value≤residual power value+α  (2).