RD Imaging Algorithm Based on the Waveform with Costas-FSK and 4-PSK for Synthetic Aperture Radar

Synthetic aperture radar (SAR) is an important representative of modern radar technology, which are widely used in the field of target detection, location and imaging. In order to prevent the signal transmitted by active radar from being detected and intercepted by the enemy, the radar waveform needs to have the characteristics of low interception. In this paper, the imaging performance of a complex encoded waveform in range doppler (RD) imaging algorithm is studied. By adding frequency symbol keying (FSK) based on Costas encoding and phase symbol keying (PSK) to the single frequency signal, the waveform has the characteristics of low interception with frequency hopping and high randomness. At the same time, due to the characteristic that RD algorithm's azimuth matching filter is not affected by signal waveform, it still maintains good target detection and imaging performance based on this waveform.