Báo cáo hóa học: " Vector perturbation based adaptive distributed precoding scheme with limited feedback for CoMP systems"

Vector perturbation based adaptive distributed precoding scheme with limited feedback for CoMP systems | Zhang et al. EURASIP Journal on Wireless Communications and Networking 2011 2011 8 http content 2011 1 8 o EURASIP Journal on Wireless Communications and Networking a SpringerOpen Journal RESEARCH Open Access Vector perturbation based adaptive distributed precoding scheme with limited feedback for CoMP systems Tiankui Zhang 1 Xiaochen Shen1 Laurie Cuthbert2 Lin Xiao3 and Chunyan Feng1 Abstract A downlink adaptive distributed precoding scheme is proposed for coordinated multi-point CoMP transmission systems. The serving base station BS obtains the optimal precoding vector via user feedback. Meanwhile the precoding vector of each coordinated BS is determined by adaptive gradient iteration according to the perturbation vector and the adjustment factor based on the vector perturbation method. In each transmission frame the CoMP user feeds the precoding matrix index back to the serving BS and feeds back the adjustment factor index to the coordinated BSs which can reduce the uplink feedback overhead. The selected adjustment factor for each coordinated BS is obtained via the precoding vector of the coordinated BS used in the previous frame and the preferred precoding vector of the serving BS in this frame. The proposed scheme takes advantage of the spatial non-correlation and temporal correlation of the distributed MIMO channel. The design of the adjustment factor set is given and the channel feedback delay is considered. The system performance of the proposed scheme is verified with and without feedback delay respectively and the system feedback overhead is analyzed. Simulation results show that the proposed scheme has a good trade-off between system performance and the system control information overhead on feedback. Keywords Coordinated multi-point Distributed precoding Limited feedback Vector perturbation Adjustment factor I. Introduction Coordinated multi-point CoMP transmission reception is considered as one of the key potential technologies