Blind estimation of diffused multipath vector channels for DS-CDMA systems

Abstract

In the antenna array wideband DS-CDMA systems, the propagation medium is a vector channel. Moreover the multipaths that define the channel are spatially and temporally diffused such that each multipath appears as a cluster rather than a point like signal source. Hence, channel estimation techniques that do not exploit the structure of the vector channel become inefficient. In this context, a subspace approach to estimate the diffused vector channels for multi-user wideband DS-CDMA systems is being proposed. The diffused vector channel is parameterized in terms of multipath directions and times of arrival. Then, by employing the structure of the developed diffused vector channel, a powerful blind near-far resistant channel estimation algorithm is derived. Simulation results are provided to illustrate the efficiency of the algorithm.