Time-varying Signature Vectors Estimation for Multicarrier CDMA Systems

In this paper, a blind adaptive signature vectors estimation algorithm for Multicarrier (MC) CDMA system in rapidly time-varying multipath fading channel is proposed. This algorithm adopts PROTEUS algorithm to estimate signal subspace and is an adaptive low dimension implementation of subspace projection method in virtue of the special update form of PROTEUS algorithm. In the case that multiple antennas are deployed to increase the capacity of CDMA systems, the proposed algorithm can estimate time-varying spatial-temporal signature vectors. This method has low computational complexity and good real-time tracking capability for rapidly time-varying channel. Monte-Carlo simulations results demonstrate the estimation and convergence performance of the proposed algorithm.