Synchronization Probabilities using Conventional and MVDR Beam Forming with DOA Errors

In this paper, code synchronization probabilities of the direct sequence spread spectrum (DS/SS) system are investigated when the receiver utilizes an adaptive antenna array. Performance studies of three beam forming algorithms in the presence of direction-of-arrival (DOA) errors are presented. The investigated algorithms are the conventional, the minimum variance distortionless response (MVDR), and the MVDR+ADL where the MVDR algorithm is enhanced against DOA error via the adaptive diagonal loading (ADL). The paper includes a large number of analytical and simulation results where the effects of DOA errors are investigated. It can be concluded that the MVDR beam former is more sensitive to DOA errors than the conventional beam former, especially, at large DOA errors and high signal-to-noise-ratio (SNR) values. However, this sensitivity can be reduced notably by using the ADL.