Asymptotic Distortion Performance of Source-Channel Diversity over Multihop and Relay Channels

—A key challenge in the design of real-time wireless multimedia systems is the presence of fading coupled with strict delay constraints. A very effective answer to this problem is the use of diversity achieving techniques to overcome the fading nature of the wireless channels caused by the mobility of the nodes. The mobility of the nodes gives rise to the need of cooperation among the nodes to enhance the system performance. This paper focuses on comparing systems that exhibit diversity of three forms: source coding diversity, channel coding diversity, and user cooperation diversity implemented through multihop or relay channels with amplifyand-forward or decode-and-forward protocols. Commonly used in multimedia communications, performance is measured in terms of the distortion exponent, which measures the rate of decay of the end-to-end distortion at asymptotically high signal-to-noise ratio (SNR). For the case of repetition coding at the relay nodes, we prove that having more relay...

• Type: Journal
• Year: 2010
• Where: TMC
• Authors: Karim G. Seddik, Andres Kwasinski, K. J. Ray Liu
• Keywords: Distortion Exponent, Optimum Number, Relay, TMC 2010