CIF: Small: Energy Efficiency in Wireless Communications under Queueing Constraints

抽象?无线通信的两个关键特性是随机变化的信道条件和有限的能量资源，这两个特性极大地影响了系统的设计和性能。在无线系统中，由于多径衰落、移动性和环境变化，接收信号的功率随时间和距离随机波动。此外，移动无线系统只能配备有限的能源资源，因此在大多数应用中，节能操作是至关重要的要求。在许多无线通信系统中，除了节能操作外，满足一定的服务质量（QoS）要求对于提供可接受的性能和质量至关重要。例如，在IP语音（VoIP）、交互式视频（如视频会议）和无线系统中的流视频应用中，延迟是一个关键的QoS度量。因此，下一代无线系统的核心设计挑战是提供最佳的性能水平，同时有效地利用能源并满足某些QoS约束（例如，延迟、数据包丢失、缓冲区违规概率），下一代无线系统的愿景是随时随地以可靠和健壮的方式提供通信。本研究的总体目标是通过对信息和排队理论方面的统一分析，确定在排队约束下运行的无线系统的能源效率的基本限制。研究人员将采用一种新的方法，通过结合信息论工具（如最小比特能量和宽带斜率）和排队论工具（如有效带宽和有效容量）来分析能源效率。该项目旨在通过严格建立缓冲约束下能源效率的基本限制来建立一个强大的分析框架，同时也具有在试验台进行实验并与理论结果进行比较的目标。

Abstract ? NSF 0917265The two key characteristics of wireless communications that greatly impact system design and performance are randomly-varying channel conditions and limited energy resources. In wireless systems, the power of the received signal randomly fluctuates over time and distance due to multipath fading, mobility, and changing environment. Moreover, mobile wireless systems can only be equipped with limited energy resources, and hence energy efficient operation is a crucial requirement in most applications. In many wireless communication systems, in addition to energy-efficient operation, satisfying certain quality-of-service (QoS) requirements is of paramount importance in providing acceptable performance and quality. For instance, in voice over IP (VoIP), interactive-video (e.g., videoconferencing), and streaming-video applications in wireless systems, latency is a key QoS metric. Therefore, the central design challenge in next-generation wireless systems, which has the vision of providing communications anytime, anywhere in a reliable and robust fashion, is to provide the best performance levels while making efficient use of energy resources and satisfying certain QoS constraints (e.g., latency, packet loss, buffer violation probability). The overall goal of this research is to identify the fundamental limits on the energy efficiency of wireless systems operating under queueing constraints through a unified analysis of information- and queueing-theoretic aspects. The investigators will employ a novel approach to analyze the energy efficiency by combining information-theoretic tools, such as minimum bit energy and wideband slope, with queueing-theoretic tools, such as effective bandwidth and effective capacity. This project seeks to establish a strong analytical framework by rigorously establishing fundamental limits on the energy efficiency under buffer constraints, and also at the same time has the goal of conducting experiments with a testbed and making comparisons with the theoretical findings.