Robust Moving Target Detection for Distributed MIMO Radar in Non-Homogeneous Clutter

In this paper, we consider the problem of moving target detection (MTD) in distributed multiple-input multiple- output (MIMO) radar in non-homogeneous environments with robustness against clutter mismatch. The non-homogeneous clutter is modeled in the Doppler domian as a linear combination of multiple discrete scatterers whose Doppler frequencies and powers vary from range bin to another and from transmit- receive pair to another. We develop a new method for MTD with robustness against mismatch between the actual and presumed discrete clutter Doppler frequencies. The proposed method first obtains an accurate estimate of the non-homogeneous clutter Doppler frequencies for every transmit-receive pair in the system using computationally-efficient fast Fourier transform (FFT)- based techniques. Then, the method mitigates the heterogeneous clutter by projecting the received data onto the orthogonal subspace of the discrete clutter, followed by the application of generalized-likelihood ratio test (GLRT) detection. Simulation examples are provided to demonstrate the robustness of the proposed GLRT over existing techniques.