Stochastic Gradient Adaptive Beamforming in DSSS Receiver Employing Antenna Array

A stochastic gradient adaptation(SGA) of antenna array receiver in DSSS system is proposed in this article, the beamformers are updated by using the perturbation vector that gives the largest correlator output, and the chip-phase delay of PN code is estimated by maximizing the output of matched filter at the same time. The beamformed signal power is maximized without jammer input, and the signal-to-interference-plus-noise-ratio (SINR) is maximized with strong jammer input. Under the circumstance of low signal-to-noise radio(SNR) and strong jammer from different spatial direction, computer simulations show that the proposed SGA beamforming converges robustly and that the PN code acquisition is completed simultaneously.