MIMO Relaying With Linear Processing for Multiuser Transmission in Fixed Relay Networks

In this paper, a novel relaying strategy that uses multiple input multiple output (MIMO) fixed relays with linear processing to support multiuser transmission in cellular networks is proposed. The fixed relay processes the received signal with linear operations and forwards the processed signal to multiple users creating a multiuser MIMO relay. This paper proposes upper and lower bounds on the achievable sum rate for this architecture assuming zero forcing dirty paper coding at the base station, neglecting the direct links from the base station to the users, and with certain structure in the relay. These bounds are used to motivate an implementable multiuser precoding strategy that combines Tomlinson-Harashima precoding at the base station and linear signal processing at the relay, adaptive stream selection, and QAM modulation. Reduced complexity algorithms based on the sum rate lower bounds are used to select a subset of users. Simulations compare the upper bounds, lower bounds, and ...

• Type: Journal
• Year: 2008
• Where: TSP
• Authors: Chan-Byoung Chae, Taiwen Tang, Robert W. Heath Jr., Sunghyun Cho
• Keywords: Lower Bounds, Relay, Sum Rate, TSP 2008