SLNR precoding based on QBC with limited feedback in downlink CoMP system

3GPP LTE-Advanced has adopted the coordinated multi-point transmission and reception (CoMP) technique as a new promising scheme. The CoMP technique can reduce the inter-cell interference (ICI) effectively, which has a great potential for enhancing cell-edge user data rate/coverage and cell throughput significantly. For downlink CoMP, most research work mainly focuses on precoding schemes with explicit feedback in joint processing/transmission (CoMP-JP) mode. However the explicit feedback type needs a high overhead under FDD mode. In this paper, we propose a signal-to-leakage-and-noise ratio (SLNR) precoding scheme based on quantization-based combining (QBC) with limited feedback in downlink CoMP system. The QBC can convert the MIMO channel into a vector channel, and then the UE feeds back the index of its quantized channel according to the codebook, which further reduces the feedback resources. Simulation results suggest that the SLNR precoding scheme based on QBC with limited feedback provides appreciable performance improvement as compared with the conventional SLNR precoding scheme with limited feedback.