An Improved Approach of Reducing Feedback for Precoded MIMO-OFDM System

In this paper, we investigated the usage of the subspace tracking for precoded multiple-input multiple-output (MIMO-OFDM) systems with limited- rate feedback, which exploits the frequency correlation between adjacent subcarriers, and proposed a novel approach of generating preceding codebook for this method, which is derived from the analysis of tracking and preceding codebook generation method. The numerical simulation shows the proposed approach achieves about 1.3 dB gain than the tracking approach, which uses the original codebook when bit error rate (BER) is 10^-3, with the same computation complexity and overheads.