Joint Source and Relay Precoding Designs for MIMO Two-Way Relaying Based on MSE Criterion

Abstract

Properly designed precoders can significantly improve the spectral efficiency of multiple-input multipleoutput (MIMO) relay systems. In this paper, we investigate joint source and relay precoding design based on the mean-square-error (MSE) criterion in MIMO two-way relay systems, where two multi-antenna source nodes exchange information via a multi-antenna amplify-and-forward relay node. This problem is non-convex and its optimal solution remains unsolved. Aiming to find an efficient way to solve the problem, we first decouple the primal problem into three tractable sub-problems, and then propose an iterative precoding design algorithm based on alternating optimization. The solution to each sub-problem is optimal and unique, thus the convergence of the iterative algorithm is guaranteed. Secondly, we propose a structured precoding design to lower the computational complexity. The proposed precoding structure is able to parallelize the channels in the multiple access (MAC) phase and broadcast (BC) phase. It thus reduces the precoding design to a simple power allocation problem. Lastly, for the special case where only a single data stream is transmitted from each source node, we present a source-antenna-selection (SAS) based precoding design algorithm. This algorithm selects only one antenna for transmission from each source and thus requires lower signalling overhead. Comprehensive simulation is conducted to evaluate the effectiveness of all the proposed precoding designs.

Optimal DoF Region for the Asymmetric Two-Pair MIMO Two-Way Relay Channel

“…In this subsection, we illustrate how to achieve the DoF tuple d = (5, 3, 3, 1) under the antenna 6,5,4,4,9). In this example, there are min{5, 3} = 3…”

“…Nowadays, a relay has become very much like a wireless gateway where multiple users share a common relay and communicate with each other. A typical representative is the two-way relay channel (TWRC) [4]- [6], where two users exchange information with each other through a relay. The success of two-way relaying owes to the invention of physical layer network coding (PLNC) [7], [8], which almost doubles the spectral efficiency compared with traditional one-way relaying [9], [10].…”

Linear Precoding Scheme Design for MIMO Two‐Way Relay Systems with Imperfect Channel State Information

“…In the actual communication system, the reliability of the communication link could be ensured by minimizing the mean square error (MSE) of the receiver. In references [6,7] analysis under the condition of perfect channel state information (CSI), the precoding algorithm regards the MSE at two source nodes as the optimization target; the study [8] presents the complete CSI and the joint optimization method based on the criterion of MSE duality of two-way MIMO relay system. In [9], the precoding algorithm of amplifyand-forward MIMO two-way relay system based on channel capacity analysis is studied under limited channel feedback condition.…”

QoS-aware multihop routing in wireless sensor networks with power control using demodulation-and-forward protocol

“…Extensive research work can be found in this area [1][2][3][4][5][6][7][8][9][10]. In [2][3][4][5][6], the multiple-input multiple-output (MIMO) techniques was deployed to increase the transmission rate. Various algorithms to optimize the resources and route planning can be found in [7][8][9][10].…”