QR decomposition based blind channel acquisition and estimation for DS-CDMA

Abstract

The problems of blind timing acquisition and channel estimation for DS-CDMA signals in multipath fading channels are investigated. Methods based on QR decompositions are proposed. These methods perform comparable or even better than subspace based methods with an order lower complexity. Furthermore, the methods exhibit significantly more robustness to channel order mismatch. Based on the acquired timing information, channel estimation algorithms are also developed which are competitive with the previously proposed subspace based channel estimation algorithms. In addition, a channel order estimation algorithm is proposed for the scenario where the order is unknown. Performance of the proposed algorithms is evaluated through simulation and comparison to Cramer-Rao lower bounds.