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Home | Seminars and Symposia | Past seminars/symposia: Friday, January 16, 2015

DTC Seminar Series

Approaching the Asymptotic Sum-Capacity of MIMO Cellular Two-Relay Channel


Xin Wang
Department of Communication Science and Engineering
Fudan University, China

Friday, January 16, 2015
4:00 p.m. reception
4:15 p.m. seminar

401/402 Walter Library

In this talk, we consider the transceiver and relay design of multiple-input multiple-output (MIMO) cellular two-way relay channel (cTWRC), where a multi-antenna base station (BS) exchanges information with multiple mobile stations via a multi-antenna relay station (RS). We propose a novel two-way relaying scheme to approach the sum capacity of the MIMO cTWRC. The key contribution is a new non-linear lattice-based precoding technique to precompensate the inter-stream interference, so as to achieve efficient interference-free lattice decoding at the relay. We derive sufficient conditions for the proposed scheme to asymptotically achieve the sum capacity of the MIMO cTWRC in the high signal-to-noise ratio (SNR) regime. To fully exploit the potential of the proposed scheme, we also pursue the optimal power allocation at the BS and the RS to maximize the weighted sum-rate of the MIMO cTWRC in the general SNR regime. We establish that the problem can be formulated as a monotonic program, and a polyblock outer approximation algorithm is developed to find the globally optimal solution with guaranteed convergence.


Xin Wang received his B.Sc. and M.Sc. degrees from Fudan University, Shanghai, China, in 1997 and 2000, respectively, and the Ph.D. degree from Auburn University in 2004, all in Electrical Engineering. From September 2004 to August 2006, he was a Postdoctoral Research Associate with the Department of Electrical and Computer Engineering, University of Minnesota, after which he joined the Department of Computer & Electrical Engineering and Computer Science at Florida Atlantic University, where he is now an Associate Professor. He is currently also a Distinguished Professor with the Department of Communication Science and Engineering at Fudan University, China. His research interests include stochastic network optimization, energy-efficient communications, cross-layer design, and signal processing for communications.