Robust Communications through Decentralized, Backhaul Limited, Wireless Networks

Abstract

Cooperation among nodes of ad hoc or cellular wireless networks enables decentralized array processing for enhanced diversity, multiplexing gain or interference rejection. For example, distributed reception nodes in a wireless network may be connected to a central processor via (wireless or wired) backhaul links allowing some degree of joint processing of the received signals.

Due to the decentralized nature of processing, the resources available for cooperation (e.g., the backhaul links) are constrained in terms of capacity and reliability.

We overview information-theoretic approaches to decentralized array processing via limited-capacity and possibly unreliable backhaul links. In particular we address robust communication strategies and put emphasis on practical aspects such as imperfect information regarding the channel state and the signaling (modulation, coding) shared by transmitters and receivers.

We discuss first cooperation scenarios with perfect channel state information and investigate the impact of lack of information regarding the codebooks (oblivious processing) on distributed multiantenna and cellular systems with cooperation base stations. Then we turn to analyzing similar models in the absence of perfect channel state information. Robust coding strategies are designed based on the broadcast coding approach (or unequal error protection codes).

Based on joint studies with E. Erkip, A. Goldsmith, D. Gunduz, H. V. Poor, A. Sanderovich, O. Simeone and O. Somekh.

Biography

Professor Shlomo Shamai (Shitz) received the B.Sc., M.Sc., and Ph.D. degrees in electrical engineering from the Technion—Israel Institute of Technology, in 1975, 1981 and 1986 respectively. During 1975-1985 he was with the Communications Research Labs in the capacity of a Senior Research Engineer. Since 1986 he is with the Department of Electrical Engineering, Technion—Israel Institute of Technology, where he is now the William Fondiller Professor of Telecommunications. His research interests encompass a wide spectrum of topics in information theory and statistical communications.  He is especially interested in theoretical limits in communication with practical constraints, multi-user information theory and spread spectrum systems, multiple-input-multiple-output communications systems, information theoretic models for wireless networks and systems, information theoretic aspects of magnetic recording, channel coding, combined modulation and coding, turbo codes and LDPC, in channel, source, and combined source-channel applications, iterative detection and decoding algorithms, coherent and noncoherent detection and information theoretic aspects of digital communication in optical channels.

Dr. Shamai (Shitz) is an IEEE Fellow, and the recipient of the 2011 Claude E. Shannon Award. He is the recipient of the 1999 van der Pol Gold Medal of the Union Radio Scientifique Internationale (URSI), and a co-recipient of the 2000 IEEE Donald G. Fink Prize Paper Award, the 2003, and the 2004 Joint IT/COM Societies Paper Award, the 2007 Information Theory Society Paper Award, the 2009 European Commission FP7, Network of Excellence in Wireless COMmunications (NEWCOM++) Best Paper Award, and the 2010 Thomson Reuters Award for International Excellence in Scientific Research. He is also the recipient of the 1985 Alon Grant for distinguished young scientists and the 2000 Technion Henry Taub Prize for Excellence in Research.

He has served as Associate Editor for the Shannon Theory of the IEEE Transactions on Information Theory, and has also served on the Board of Governors of the Information Theory Society.

Shlomo Shamai´s homepage