Abstract: According to the signal model of the coherent MIMO radar, its array signal processing flow is given in this paper. Based on this, OFDM signal processing techniques are studied. Aiming at the performance of cross-correlation and auto-correlation, signal parameters are discussed on the basis of OFDM signal model. Several problems in OFDM signal processing are studied, such as motion compensation, beam lobe broadening, transmit beam synthetic wideband, and so on. The amplitude error and the phase error between channels are analyzed. The method of channel calibration is given and is verified by simulation. Details in signal processing and assessment of the main computation load are given. It′s instructive in engineering application.