This research project investigates the design, analysis, and implementation of resource efficient integrative transceivers and retransmission diversity in broadband multi-input-multi-output (MIMO) wireless communications. The development and exploitation of MIMO technologies and Automatic Repeat reQuest (ARQ) protocols have been popular subjects of wireless research. Hybrid ARQ is effective as protection against packet error in wireless communications, while MIMO transceivers have demonstrated significant performance gains at the wireless physical layer. However, traditional approaches treat MIMO schemes and ARQ as independent mechanisms in wireless networks. The design integration of hybrid ARQ protocols with MIMO transceivers has received scant coverage and has not been well utilized. As more and more mainstream products begin to adopt MIMO technologies in wireless LAN and other wireless systems, there is an urgent need to exploit and achieve the full potential benefit offered by integrating wireless ARQ and MIMO designs. This research project investigates the efficient integration of ARQ with broadband MIMO physical layer.
Simultaneously considering both designs of ARQ protocols and MIMO transceivers, the investigations of this project are systematic, integrative, and broadly applicable. Unlike in traditional wireless designs where ARQ and MIMO technology are treated separately, this integrative design approach opens a new door to developing future advanced wireless systems that are power and bandwidth efficient. While the advantages of cross-layer optimization are well known, the integrative design of ARQ protocols and their corresponding MIMO transceivers provides a concrete and tangible approach to cross-layer network design. Focusing on bandwidth and power efficiency, the project goal is to optimize and adapt ARQ (Automatic Repeat reQuest) protocols for MIMO wireless systems to improve performance and scalability. The research presents new capacity analysis and transceiver optimization of progressive MIMO precoding to better exploit the ARQ retransmission diversity. The investigators develop design of bandwidth and power efficient transceiver technologies in full integration with new scalable ARQ designs to significantly improve the performance of end user applications. The results of this project provide new formulation of wireless MIMO channel estimation algorithms particularly tailored for bandwidth efficient and scalable hybrid ARQ protocols in future broadband wireless communication systems.
