DAC: Distributed Asynchronous Cooperation for Wireless Relay Networks

—Cooperative relay is a communication paradigm that aims to realize the capacity of multi-antenna arrays in a distributed manner. However, the symbol-level synchronization requirement among distributed relays limits its use in practice. We propose to circumvent this barrier with a cross-layer protocol called Distributed Asynchronous Cooperation (DAC). With DAC, multiple relays can schedule concurrent transmissions with packet-level (hence coarse) synchronization. The receiver then extracts multiple versions of each relayed packet via a collision-resolution algorithm, thus realizing the diversity gain of cooperative communication. We demonstrate the feasibility of DAC by prototyping and testing it on the GNURadio/USRP software radio platform. To explore its relevance at the network level, we introduce a DAC-based MAC, and a generic approach to integrate the DAC MAC/PHY layer into a typical routing algorithm. Considering the use of DAC for multiple network flows, we analyze the fundam...

• Type: Journal
• Year: 2010
• Where: INFOCOM
• Authors: Xinyu Zhang, Kang G. Shin
• Keywords: Communications, Diversity Gain, INFOCOM 2010, Relays, Symbol-level Synchronization Requirement