A Study of Timing Control and Array Weight Error Effects in the Antenna Array Aided Uplink Synchronous DS-CDMA System

Abstract

We investigate the effects of timing misalignment and imperfect array weight vector generation on the antenna array (AA)-aided uplink synchronous DS-CDMA system. Previous works have assumed perfect uplink synchronization among first path's receiving timing and perfect array weight vector calculation. Unfortunately, practical system will experience of timing control error (TCE) and array weight error (AWE). Accordingly, this letter undertakes an analysis of the impacts of TCE and AWE, evaluating a closed form BER performance considering the important factors such as the number of antennas, the variance of AWE and the misalignment factor as a measure of the TCE in dispersive Rayleigh multi-path fading channel. Additionally, the scenario of synchronous uplink with the cell-site AA is compared with asynchronous scheme. Numerical results show that the performance in the synchronous uplink can be further improved, even at high levels of AWE and TCE.