Analysis of Steering Vector Mismatch on Adaptive Noncoherent Integration

Amplitude and phase errors can cause mismatches between the hypothesized signal vector and the steering vector of an antenna array. A generalized likelihood ratio test (GLRT) for signal detection with multiple coherent processing intervals (CPIs) in unknown interference is derived. The detection performance of the resulting adaptive noncoherent integration (NCI) algorithm is analyzed along with the effect of steering vector mismatch on detection performance. Detection performance and the effect of steering vector mismatch are illustrated with results for both a nonfluctuating signal model and a CPI-to-CPI fluctuating signal model. It is shown that a signal-to-interference-plus-noise ratio (SINR) loss factor inherent to the algorithm in effect limits the performance gain due to NCI of mismatched signals.