Waveform design for joint radar-communication system with multi-user based on MIMO radar

The joint radar-communication system integrates the function of detection and data transmission to reduce interference and improve the overall spectrum efficiency, as well as to reduce total volume of devices in vehicles, which is widely used in the intelligent transportation systems. Among these joint systems, a MIMO radar based system has significant advantage for multi users with orthogonal waveforms transmitted by each antenna. In order to realize high speed transmission, a quasi-orthogonal multi-carrier LFM-CPM waveform is proposed for the joint system. This waveform preserves the characteristics of LFM with constant envelope and continuous phase, so that the distortion caused by the nonlinearity of the high power amplifier and the reduction of effective working distance can be avoided. The spectral efficiency of the proposed waveform is much higher than the 1-bit multi-carrier LFM waveform and simulation of bit error rate (BER) performance is close to that of single-carrier LFM-CPM with no interference. The simulation of ambiguity function shows that the random communication symbols has little influence on the radar subsystem. In a word, the shared waveform based on multi-carrier LFM-CPM and MIMO radar can meet the need of the detection and multi-user transmission at the same time, and is suitable for the intelligent transportation systems.