Signal processing device and signal processing method

1 . A signal processing device comprising:

a memory storing software instructions; and

one or more processors configured to execute the software instructions to:

record received signals to generate observed SAR images;

generate three-dimensional information with reliability including three-dimensional information involving intensity and an estimated value of a phase at a three-dimensional position reconstructed using the observed SAR images and imaging conditions, and information indicating reliability of the three-dimensional information; and

calculate phase signals for all pixels in an analyzed area for the imaging conditions of SAR images to be analyzed, and calculate the information indicating reliability of the phase signals based on the information indicating reliability of the three-dimensional information.

2 . The signal processing device according to claim 1 , wherein the one or more processors are configured to execute the software instructions to calculate the information indicating reliability of the three-dimensional information by evaluating a discrepancy between a received signal and a predicted signal predicted from the generated three-dimensional information for each of the intensity and the phase.

3 . The signal processing device according to claim 1 , wherein the one or more processors are configured to execute the software instructions to evaluate how reliable each estimate in the generated three-dimensional information is among possible values.

4 . The signal processing device according to claim 1 , wherein the one or more processors are configured to execute the software instructions to calculate a function that expresses information on how reliable what values are for the intensity and the phase at each position in a three-dimensional space as three-dimensional information with reliability.

5 . The signal processing device according to claim 1 , wherein the one or more processors are configured to further execute the software instructions to eliminate the phase signals for the pixels in the analyzed area, referring to the information indicating reliability of the phase signal.

6 . The signal processing device according to claim 5 , wherein the one or more processors are configured to further execute the software instructions to perform a first change detection process for detecting change in the analyzed area using the SAR image of the analyzed area in which the phase signals have been eliminated.

7 . The signal processing device according to claim 5 , wherein the one or more processors are configured to further execute the software instructions to perform a second change detection process for detecting change in the analyzed area using the SAR image of the analyzed area in which the phase signals have been eliminated, and

wherein in the second change detection process, the one or more processors are configured to execute the software instructions to calculate a degree of similarity of each SAR image to be analyzed for each pair of multiple SAR images to be analyzed, and detect the change using multiple calculated degrees of similarity.

8 . The signal processing device according to claim 1 , wherein the one or more processors are configured to further execute the software instructions to eliminate phase signals for the pixels in the analyzed area.

9 . The signal processing device according to claim 8 , wherein the one or more processors are configured to further execute the software instructions to detect change in the analyzed area using the SAR image of the analyzed area in which the phase signals have been eliminated, referring to the information indicating reliability of the phase signals.

10 . The signal processing device according to claim 8 , wherein the one or more processors are configured to further execute the software instructions to perform a change detection process for detecting change in the analyzed area using the SAR image of the analyzed area in which the phase signals have been eliminated, referring to the information indicating reliability of the phase signals, and

wherein in the change detection process, the one or more processors are configured to execute the software instructions to calculate a degree of similarity of each SAR image to be analyzed for each pair of multiple SAR images to be analyzed, and detect the change using multiple calculated degrees of similarity.

11 . A signal processing method comprising:

recording received signals to generate observed SAR images;

generating three-dimensional information with reliability including three-dimensional information involving intensity and an estimated value of a phase at a three-dimensional position reconstructed using the observed SAR images and imaging conditions, and information indicating reliability of the three-dimensional information; and

calculating phase signals for all pixels in an analyzed area for the imaging conditions of SAR images to be analyzed, and calculating the information indicating reliability of the phase signals based on the information indicating reliability of the three-dimensional information.

12 . A non-transitory computer readable recording medium storing a signal processing program which, when executed by a processor, performs:

recording received signals to generate observed SAR images;

generating three-dimensional information with reliability including three-dimensional information involving intensity and an estimated value of a phase at a three-dimensional position reconstructed using the observed SAR images and imaging conditions, and information indicating reliability of the three-dimensional information; and

calculating phase signals for all pixels in an analyzed area for the imaging conditions of SAR images to be analyzed, and calculating the information indicating reliability of the phase signals based on the information indicating reliability of the three-dimensional information.