Study on Resolution Limit of Space-Time 2-D Joint Processing

Aiming at space-time snapshots received by an array antenna, the method of space-time joint resolution limit (STJRL) is studied on the basis of statistic detection theory. It could be derived from minimum probability of error criterion that, in Gauss white noise context, the STJRL is approximated by a simple expression related to the signal to noise rate (SNR), the array manifold, the signal waveform and the resolution successive rate. The comparison of STJRL and 1-D resolution limit of traditional radar antenna indicates that space-time 2-D processing could achieve higher performance as it exploits two dimensional differences between target echoes. Through Monte Carlo simulation, the STJRL was also compared with the empirical performance of the Akaike information criterion (AIC) method and mimimun desc-ription length method (MDL). The results show that the curves of SNR versus δ_t/δ_tf obtained from AIC and MDL stay above the curve predicted by STJRL, and that the curve of SNR versus δ_t/δ_tf from likelihood ratio test (LRT) detector matches the theoretic STJRL curve well.