Antenna Device and Signal Processing Method

An antenna device comprising:

• a plurality of first antenna elements respectively configured to receive a first incident waves of a predetermined polarization direction coming from an object and output a first received signal on a basis of a received first incident waves;
• a plurality of second antenna elements respectively configured to receive a second incident waves of a polarization direction different from the first incident waves received by the first antenna element and output a second received signal on the basis of a received second incident waves;
• a plurality of first modulating units respectively configured to modulate the first received signal output from the first antenna element into a third received signal having a first phase and a first frequency which differs corresponding to each of the first antenna elements;
• a plurality of second modulating units respectively configured to modulate the second received signal output from the second antenna element into a fourth received signal having a second phase different from the first phase and a second frequency which differs corresponding to each of the second antenna elements;
• a synthesizing unit configured to synthesize the plurality of the third received signals respectively modulated by the plurality of the first modulating units and the plurality of the fourth received signals respectively modulated by the plurality of the second modulating units, and generates a synthetic signal;
• a signal processing unit configured to perform predetermined signal processing on the synthetic signal;
• and
• an extracting unit configured to extract fifth received signals from the synthetic signal on which has been performed the predetermined signal processing, each of the fifth received signal having a frequency and a phase equal to the frequency and the phase of the third received signal modulated by the first modulating units and the fourth received signal modulated by the second modulating units.

A signal processing method comprising:

• acquiring a plurality of first received signals from a plurality of antenna elements including at least a first antenna element that receives incident waves of a predetermined polarization direction and a second antenna element that receives incident waves of a polarization direction different from the incident waves received by the first antenna element;
• modulating the plurality of acquired first received signals into second received signals, the second received signals having a frequency corresponding to a position of the antenna element and having a phase corresponding to the polarization directions of the incident waves received by the antenna element;
• generating a synthetic signal by synthesizing the plurality of modulated second received signals;
• performing predetermined signal processing on the synthetic signal;
• and
• extracting third received signals from the synthetic signal on which has been performed the signal processing, each of the third received signals having a frequency and a phase equal to the frequency and the phase of the second received signal modulated by the modulating step.