CIF: Small: Cognitive Spectrum Access: Fundamental Limits, Protocols, and Performance Analysis

通过未授权频谱的无线接入是未来宽带计划的主要组成部分。不幸的是，未授权频带是拥塞的，并且现有技术不能为具有不同接入优先级和需求的用户提供质量保证。 缺乏服务质量保证是提供多媒体内容和促进宽带通信的主要障碍。 迫切需要通过动态频谱感测、学习和频谱机会的认知共享来提供未授权频谱的分布式分层接入的技术。 该研究为多类用户共享无线频谱的认知接入提供了数学理论和实用方法。 本研究的技术方法是基于某些载波侦听策略的结构优化。这些政策的最优性和简单性，导致新的实用，但最佳的解决方案，从不同的优先级用户之间的认知频谱共享。 总体目标有两个方面。 首先，它的目的是获得一个基本的认知频谱接入的层次网络中的限制的理解。 特别是，它的特点是最大吞吐量和有效带宽区域的用户为不同的优先级，利用结构的最佳策略认知感知和访问。 其次，本研究开发了共享频谱的分散认知接入的工程实用解决方案。 特别是，新的多用户传感和接入协议的开发和测试的实际应用。衰落，干扰和其他实施问题的影响也进行了研究。 这项研究包括一个重要的教育组成部分，旨在将前沿研究与本科和研究生课程相结合。

Wireless access through unlicensed spectrum is a major component for future broadband initiatives. Unfortunately, unlicensed frequency bands are congested, and existing technologies do not provide quality assurance for users with different access priorities and needs. The lack of quality of service guarantee is a key roadblock to providing multimedia content and facilitating broadband communications. There is a cogent need for technologies that provide distributed hierarchical access of unlicensed spectrum through dynamic spectrum sensing, learning, and cognitive sharing of spectrum opportunities. This research develops mathematical theory and practical methodologies for the cognitive access of wireless spectrum shared by multiple classes of users. The technical approaches of this research are based on the structural optimality of certain carrier sensing policies. The optimality and simplicity of these policies result in new practical yet optimal solutions to cognitive spectrum sharing among users from different priority classes. The overall objective is twofold. First, it aims at gaining a foundational understanding of the limits of cognitive spectrum access in hierarchical networks. In particular, it characterizes the maximum throughput and effective bandwidth regions for users for different priority classes by exploiting structures of optimal policies for cognitive sensing and access. Second, this research develops engineering practical solutions for decentralized cognitive access of shared spectrum. In particular, new multiuser sensing and access protocols are developed and tested for practical applications. Effects of fading, interference and other implementation issues are also examined. This research includes a significant education component aimed at integrating frontier research with undergraduate and graduate curricula.