Low-complexity optimal spatial channel pairing for AF-based multi-pair two-way relay networks  

作　　者：SHU Feng CHEN Yu YOU XiaoHu LU JinHui 

机构地区：[1]School of Electronic and Optical Engineering, Nanjing University of Science and Technology [2]National Mobile Communications Research Laboratory, Southeast University [3]Ministerial Key Laboratory of JGMT, Nanjing University of Science and Technology

出　　处：《Science China(Information Sciences)》2014年第10期42-51,共10页中国科学（信息科学）（英文版）

基　　金：supported in part by open research fund of National Mobile Communications Research Laboratory,Southeast University(Grant No.2013D02);Fundamental Research Funds for the Central Universities(Grant No.30920130122004);National Natural Science Foundation of China(Grants Nos.61271230,61301107)

摘　　要：This paper considers a multi-pair two-way relay system with multi-antenna users and proposes a low-complexity optimal spatial channel pairing （SCP） strategy at the relay station （RS） for such a system. The proposed SCP scheme, following the BD-like beamformer at RS, pairs the uplink spatial subchannels of each user pair with the corresponding downlink spatial subchannels by maximizing sum-rate （Max-SR）. Furthermore, a new mathematical inequality （arrangement inequalities of a product） is developed and applied to obtain sufficient and necessary conditions for achieving Max-SR-SCP. This also yields a simple low-complexity implementation of the proposed SCP in contrast to the NP-hard complexity of the original Max-SR-SCP problem. Simulation results illustrate that the proposed Max-SR-SCP achieves substantial sum-rate gains over other pairing schemes.This paper considers a multi-pair two-way relay system with multi-antenna users and proposes a low-complexity optimal spatial channel pairing （SCP） strategy at the relay station （RS） for such a system. The proposed SCP scheme, following the BD-like beamformer at RS, pairs the uplink spatial subchannels of each user pair with the corresponding downlink spatial subchannels by maximizing sum-rate （Max-SR）. Furthermore, a new mathematical inequality （arrangement inequalities of a product） is developed and applied to obtain sufficient and necessary conditions for achieving Max-SR-SCP. This also yields a simple low-complexity implementation of the proposed SCP in contrast to the NP-hard complexity of the original Max-SR-SCP problem. Simulation results illustrate that the proposed Max-SR-SCP achieves substantial sum-rate gains over other pairing schemes.

关 键 词：multipair two-way relay spatial channel pairing maximizing sum-rate arrangement inequalitiesof product relaying station 

分 类 号：TN919.3[电子电信—通信与信息系统]