User cooperation in wireless networks

As the wireless communication channel is shared in nature, user cooperation is a key enabling tool to exploit the spatial multiplexing and diversity gains to improve spectrum and energy efficiency of wireless networks. User cooperation can take many forms, including the physical-layer cooperative communications, the link-layer cooperative and cognitive medium access, the network-layer cooperative routing and load balancing, the collaborative end-to-end congestion control in the transport layer, and the cooperative peer-to-peer services. The development and optimization of cooperation technologies requires interdisciplinary efforts, from advanced signal processing and communication to network protocol design and optimization. It also sparks theoretical breakthroughs in topology control, nonlinear optimization, signal processing and complex networks, and stimulates practical advances in mobile communications and networking technologies, devices and platforms.