Space-time adaptive processing （STAP） is an effective method adopted in airborne radar to suppress ground clutter. Multi- ple-input multiple-output （M1MO） radar is a new radar concept and has superiority over conventional radars. Recent proposals have been applying STAP in MIMO configuration to the improvement of the performance of conventional radars. As waveforms transmitted by MIMO radar can be correlated or uncorrelated with each other, this article develops a unified signal model incor- porating waveforms for STAP in MIMO radar with waveform diversity. Through this framework, STAP performances are ex- pressed as functions of the waveform covariance matrix （WCM）. Then, effects of waveforms can be investigated. The sensitivity, i.e., the maximum range detectable, is shown to be proportional to the maximum eigenvalue of WCM. Both theoretical studies and numerical simulation examples illustrate the waveform effects on the sensitivity of MIMO STAP radar, based on which we can make better trade-off between waveforms to achieve optimal system performance.
