A Closed-form Expression of STAP Performance for Distributed Aperture Coherence MIMO Radar

Distributed aperture coherence multi-transmit multi-receive (MIMO) radar combined with space time adaptive processing (STAP) has great advantage for moving target indication. However, the problems of non-ideal orthogonal waveform and non-stationary clutter are intertwined together, which leads to significant performance degradation of STAP. In this letter, we presented a pragmatic and accurate performance prediction model to interpret the impact mechanism of waveform properties on STAP performance. We deduced a novel clutter covariance matrix (CCM) model with the aforementioned non-ideal factors taking into consideration. On this basis, a closed-form expression of output SCNR loss is derived to predict and evaluate STAP performance. Therefrom the quantitative relationship is established between waveform properties, clutter CCM, and STAP performance. It provides a simple and effective way to predict system performance for radar system design. Finally, numerical simulation results illustrated that the mean prediction error of SCNR loss for proposed model is about 2dB less than conventional approximation model.