Enhancing Performance of Space-Time Parameter Estimation in DS-CDMA Arrays

A large number of signal processing researches are concerning with estimating unknown signal parameters from antenna arrays. In this paper, the parameter estimation problem is focused on time delay and direction-of-arrival (DOA) estimation, here called two-dimensional code acquisition. Multiple signal classification (MUSIC) is addressed to perform the two-dimensional code acquisition in direct-sequence code division multiple access (DS-CDMA) arrays, and the general performance analyses of MUSIC are given. Based on the further analyzed eigenvalues, the derived bias of MUSIC discloses that the performance of MUSIC for two-dimensional code acquisition can be improved by the increasing length of the space-time response vector.