Rao-Based Detectors for Adaptive Target Detection in the Presence of Signal-Dependent Interference

Abstract

The adaptive radar detection of a point target in the presence of signal-dependent interference, also known as system-dependent clutter, is addressed in this paper. Here, the radar signal is assumed to be an intra-pulse modulated waveform and the target is surrounded by the interference, both in range and frequency spectrum domains. In a clutter-dominant situation, the detection problem is studied under wide-sense stationary (WSS) and also non-stationary Gaussian interference processes and two closed-form detectors, respectively named WSS-Rao and NS-Rao are derived. Both analytically and using computer simulations, it is shown that the proposed detectors perform independent of the transmit signal. In addition, the proposed NS-Rao and WSS-Rao detectors ensure a constant false alarm rate with respect to the statistical characteristics of the interference. Our simulations illustrate the remarkable effectiveness of the proposed detectors compared to their upper-bound. In particular, the WSS-Rao detector can be implemented by simple scalar operations. Furthermore, in WSS scenarios with a limited number of received echoes, which happens in many practical situations, the WSS-Rao detector outperforms its competitors. It was also shown through simulations that both the NS-Rao and WSS-Rao are robust with respect to the clutter distribution.