Exploiting Interference in Wireless Networks: Protocol Design, Analysis and Implementation

无线网络中的一个主要性能限制因素是干扰。当前无线网络的设计基于干扰避免原则，该原则主张消除并发的附近传输以避免冲突，因为冲突会导致稀缺的无线带宽的浪费。关键问题是，盲目防止干扰的网络设计不是最优的，会导致带宽有限的无线网络的严重低效。随着无线网络物理层的最新进展，如果控制得当，附近链路的并发传输可以成功解码。如果发送器和接收器知道干扰结构，他们可以利用它来更好地解码他们的传输，从而极大地提高网络性能。 该方案从根本上改变了无线网络中传统的协议设计：它设计了系统地鼓励和利用干扰来提高网络性能的网络协议。具体地说，它利用三种物理层机制来利用干扰：基于叠加编码的多分组传输、基于逐次干扰消除的多分组接收和协作通信，以设计将干扰转化为优势的无线网络协议(具体地说，链路层调度和网络层路由)。 这项拟议的研究将产生对未来无线网络的设计产生重大影响的技术。该方案的范围包括协议设计、网络建模和分析，以及在实验试验台上实施选定的协议。除了对新无线技术理论和实践的潜在影响外，拟议的研究还为本科生和研究生提供了无线网络各个方面的极好培训基础。

A major performance limiting factor in wireless networks is interference. Current wireless networks are designed based on the principle of interference avoidance, which advocates for eliminating concurrent nearby transmissions to avoid collisions, as collisions result in waste of scarce wireless bandwidth. The key issue is that a network design that blindly prevents interference is sub-optimal and results in severe inefficiencies in bandwidth-limited wireless networks. With recent advances at the physical layer of wireless networks, concurrent transmissions of nearby links can be successfully decoded if controlled properly. If transmitters and receivers are aware of the interference structure, they can exploit it to better decode their transmissions, and thus greatly improve network performance. This proposal makes a fundamental shift from the traditional protocol design in wireless networks: it designs network protocols that systematically encourage and exploit interference to improve network performance. Specifically, it utilizes three physical layer mechanisms for exploiting interference: multi-packet transmission based on superposition coding, multi-packet reception based on successive interference cancellation, and cooperative communication to design wireless network protocols (specifically, scheduling at link layer and routing at network layer) that turn interference into an advantage. The proposed research will produce techniques that can have substantial impact on the design of future wireless networks. The scope of the proposal includes protocol design, network modeling and analysis, and implementation of selected protocols on an experimental testbed. In addition to potential impacts on the theory and practice of new wireless technologies, the proposed research is an excellent training ground for undergraduate and graduate students in all aspects of wireless networks.