Spatio-temporal array (STAR) DS-CDMA systems: localized scattering channel estimation

This paper is concerned with the problem of channel estimation for asynchronous DS-CDMA systems in the presence of local scattering of the multipaths. Based on a first order Taylor series expansion, the manifold vector associated with a locally scattered multipath is formulated and a new channel estimation algorithm is proposed. The proposed algorithm hinges on the patioemporal ray (STAR) manifold concept S T Ar and is a joint pread, ngle and elay stimator (SADE) of the S A D E locally scattered multipaths of the desired user. Simulation studies indicate that the proposed technique estimates the mean direction-of-arrival more closely than methods that ignore local scattering effects. NOTATION + Ü Ý Scalar . Rounded up to integer Eß + Column vector . Transpose ˆ ‰ Matrix . Conjugate transpose ˆ ‰ + Elementwise power Œ Kronecker product