Multichannel GMTI techniques to enhance integration of temporal signal energy for improved target detection

Abstract

Improvements in target detection are typically achieved by increasing the signal-to-interference-plus-noise ratio (SINR) of the received signal. For a small radar platform with power and aperture constraints, increases in SINR must come through temporal integration. Two techniques are presented here for enhancing the integration of temporal signal energy to improve detection of weak, slow-moving targets over conventional methods. Both techniques involve modifications to pre-Doppler space-time adaptive processing (STAP), a reduced-dimension STAP method that is implementable in real-time on a power-constrained platform. The two modifications include (i) development of an alternative pre-Doppler temporal weighting method, based on linear prediction, to increase the SINR of the pre-Doppler temporal output signal and (ii) development of an extended dwell temporal processing (EDTP) algorithm to integrate temporal signal energy collected over a long dwell. The EDTP algorithm is based on frequency domain analysis of the extended dwell time signal; the detection decision exploits the differences in the distribution of signal energy and noise energy over an extended dwell. EDTP algorithm performance is superior to traditional temporal processing methods in many practical scenarios: the EDTP algorithm detection rate is three times the detection rate of non-coherent integration for very low-velocity, low-SNR targets.