| Due to the development of electronic technology, passive radars with many advantages are famous both at home and abroad. This paper focusses on the passive radar detection technology based on the signal of China Mobile Multimedia Broadcasting (CMMB), and the work of this paper can be divided into three parts:Firstly, as the CMMB signal is used for communication, whose waveform and parameters are not particularly designed for the radar system, it is necessary to analyze the properties of CMMB signal by radar signal theory. This paper has designed the CMMB signal acquisition system and demonstrated the possibility of CMMB signal for radar detection by simulation and experimental results.Then, the ambiguity function of the CMMB signal with high side-lobes and peaks both in ranger and Doppler domain is not well for weak targets detection because of the shading effect of side-lobes coming from strong target echoes, which would result in losing the interest target in multi-target area and increasing the false alarm and miss alarm probability. Based on the traditional side-lobe suppression technique, this paper introduces a new and effective side-lobe and peak suppression way by combining the frame structure characteristics of CMMB signal with the weighting technique and then designed the target detection system with CMMB signal.Finally, considering that the targets are sparse in the delay-Doppler detection area, we address the sparse recovery technology into target detection and propose a sparse passive detection technology based on the CMMB signal. Simulation results have shown that our method performs a better detection result than traditional way. |
