TF-SING: Energy-Efficient Design in Wireless Networks Using Cooperative Communication

这项研究涉及无线网络中的一个关键挑战：如何利用物理层的新进展来推动上层的新设计。所使用的方法是基于搭便车的协作通信(CC)，其利用促进部分信息组合的物理层设计。节点可以接收几个部分信号，并将这些信号组合以检索完整的信号。通过有效地使用部分信号，可以用更少的节点和/或在每个节点处更小的发射功率来递送分组。研究人员提出了一种新的加权图模型，该模型能够很好地刻画CC的本质。提出的一个关键概念是链接的新概念。然后呢？路径？基于这一新的图模型，研究了CC下的两种节能设计：(1)使无线节点处于周期性休眠状态，同时保持全局控制的节能协议；活动节点的数量。(2)在保持全球连通性的同时，通过调整传输范围来控制传输能耗。在此基础上，本研究提出了一种将该图模型应用于无线网络节能设计的独特方法。本研究还设计了一种通用的局部解方法，并将其应用于解决CC下的各种与能源相关的优化问题。这项研究的中心主题很好地符合SING项目的目标，即涉及协调和沟通的基础理论和算法研究。这项研究的见解和结果有望为广泛的无线网络应用提供能效指导。

This research involves one of the key challenges in wireless networks: how to take advantage of new advances at the physical layer to push for new design at the upper layers. The approach used is hitchhiking-based cooperative communication (CC) that takes advantage of the physical layer design that facilitates the combining of partial information. A node can receive several partial signals and combine these signals to retrieve the complete signal. Through effective use of partial signals, a packet can be delivered with fewer nodes and/or less transmission power at each node. The investigator proposes a new weighted graph model that can capture the nature of CC. One key concept proposed is the new notion of ?link? and ?path? on which other graph terminologies can be defined.Based on this new graph model, the research focuses on two types of power-efficient design under CC: (1) Power saving protocols that put wireless nodes into periodical sleep states while maintaining global ?domination? of active nodes. (2) Power control for transmission energy consumption by adjusting transmission ranges while maintaining global ?connectivity?. With these, this research presents a promising and unique way of applying this graph model to energy-efficient design in wireless networks. This research also involves the design of a general methodology of localized solutions and applies it to address various energy-related optimization problems under CC. The central theme of this research fits well with the objective of the SING program on fundamental theoretical and algorithmic studies involving coordination and communication. The insights and results of this research are expected to provide guidelines for energy-efficiency for a wide range of wireless network applications.