Reception and calibration of bistatic SF ISAR imaging system with wideband receiver

The reception and calibration of bistatic stepped-frequency (SF) inverse synthetic aperture radar (ISAR) imaging system with wideband receiver are studied in this study. First, as residual carrier frequency offset and over-sampling will be introduced in the SF linear frequency modulation signal which is received by wideband receiver, a spectrum truncation, and frequency error compensation method is proposed to solve the problems. Second, a calibration method of bistatic SF ISAR imaging system based on accumulated spherical satellite echoes is proposed, since echo signals are modulated by non-ideal amplitude and phase characteristics of radar system channels, which seriously deteriorates the quality of SF imaging result. Theoretical analysis and simulation results indicate that the proposed method can effectively compensate the non-ideal characteristics of radar system channels.