Slow-Time FDA-MIMO Radar Space-Time Adaptive Processing

The multiple-input multiple-output (MIMO) radar with a frequency diverse array (FDA) acting as the transmit (Tx) array, referred to as FDA-MIMO radar, is capable of providing additional degrees-of-freedom (DOFs) in range domain, and thereby offers the potential benefits in range-dependent interference mitigation and range ambiguity resolving. The existing FDA-MIMO radar literature either simply assumes that the Tx waveforms are mutually orthogonal or employs the code division multiple access (CDMA) waveforms to extract Tx DOFs. However, for real applications of the ground moving target indication (GMTI) using the space-time adaptive processing (STAP) technique, the CDMA waveforms are not preferable due to their poor ground clutter cancellation performance. To address this issue, a novel slow-time FDA-MIMO radar, which transmits slow-time phasecoded waveforms, is developed. As the slow-time FDA-MIMO radar emits highly correlated waveforms, it is expected to achieve excellent clutter cancellation performance. In addition, a new signal processing strategy is proposed, which is capable of extracting range-dependent Tx DOFs effectively. Numerical experiments are conducted to validate the effectiveness of the proposed radar framework for STAP applications.