Compressed Sensing Detector for Wideband Radar Using the Dominant Scatterer

Wideband radars transmit wideband linear frequency modulated (FM) pulses to achieve the high range resolution. The scenario that the echo is down-converted by a mixer with a reference signal that is a replica of the transmitted pulse is assumed in this letter. Here, the complex sinusoidal signal basis (CSSB) is introduced to sparely represent the received echo. Then the compressed sensing (CS) radar receiver is designed to reduce the sampling rate; hence, the high resolution range profile (HRRP) can be acquired from low dimensional CS measurements via L1 norm-minimization. Using the statistical characteristic and the dominant scatterer, a constant false alarm rate (CFAR) detector is proposed to detect the range spread target in the complex Gaussian noise. In the new detector, the cross quasi-ambiguity function (CQAF) is selected to acquire the target feature to distinguish the range spread target from the Gaussian noise, thus constructing a close connection between the sparse basis and the target detection. Finally the proposed method is evaluated by the raw data.