Synchronization probabilities for matched filter code acquisition using DOA estimation and beamforming

This paper introduces analysis of synchronization probabilities for direct sequence (DS) spread spectrum (SS) system when the receiver is equipped with a smart antenna system and the matched filter (MF). The analyzed method first estimates direction-of-arrival (DOA) of the DS-signal, then performs beamforming, and finally makes synchronization decision based on the maximum value of the output of the MF. The analysis takes into account the fact that the DOA estimates are not perfect when finite number of samples is available. Therefore, beamforming is not necessarily perfect, which results power losses. The obtained results are compared to simulated and semianalytical ones. The sensitivity for DOA estimation error increases when the number of antennas in the array increases. It is also shown that at low signal-to-noise ratios the simulated accuracy of the DOA estimator is far away from the theoretical results. This behavior reflects also on the synchronization probabilities.