A precoding method for multiple antenna system on the Riemannian manifold

In this paper, a precoding scheme for multiple antenna systems with space-time coding over correlated Ricean channels is proposed. Based on the channel mean and receiveside spatial correlation, the proposed scheme obtains the solution of the power allocation and beamforming matrix of the precoder iteratively. Unlike most of existing precoder designs in literatures that have expensive computations and cannot guarantee the design algorithms to converge, the convergence of the proposed scheme is guaranteed. By exploiting the special structure of beamforming matrix, a steepest descent method on the Riemannian manifold is proposed for the optimization of beamforming matrix. Simulation results show that the proposed optimal scheme not only achieves superior bit error rate (BER) performance to those of the existing ones, but also provides a guaranteed-convergent solution under different channel conditions. © 2014 Engineering and Technology Publishing.