NeTS-WN: Cross-Layer Optimizations and Adaptive Protocols for Opportunistic and Collaborative Cognitive Radio Networks

本课题的重点是协作认知无线电网络(CRN)中的资源优化分配和控制。通过机会访问可用的频谱，CRN旨在通过实现更高的空间重用、可编程连接和更高的网络可用性来提高网络资源的利用率。研究议程包括旨在优化最低三层操作的集中式分析公式，以及实施这种优化结果的分布式路由和介质访问协议。在存在多个主要(频谱许可)无线电网络(PRN)的情况下，将考虑对CR通信的频谱、传输功率和速率进行联合优化。将不会假设来自PRN的反馈。将研究几种公式，这些公式在对信道动态(间接地，用户移动性)、优化窗口(分组与流时间尺度)以及功率掩码的可用性或其他方面的假设上有所不同。除了单跳优化外，该项目还将考虑分组和流时间尺度上的多通道、多路径优化。然后，优化结果将被集成到机会CRN的分布式信道接入和路径发现/维护协议的设计中。根据感兴趣的频段，CR传输上的固定功率掩模可能可用，也可能不可用。将为这两种情况制定协议。在没有固定功率掩码的情况下，将对PR干扰进行统计建模，并将其用于支持PR接收中断概率保证的MAC协议的设计。这种处理将扩展到无连接和面向连接的应用程序。该项目的跨学科性质预计将对民用和军用应用中使用的许多无线技术产生深远影响，包括传感器网络、网状网络、军用无线电和无线局域网。优化框架提供了一种通用方法，可以显著提高资源受限无线网络的总体性能、连通性和互操作性。

The focus of this project is on optimal resource allocation and control in collaborative cognitive radio networks (CRNs). Through opportunistic access to the available spectrum, CRNs aim at improving the utilization of network resources by achieving higher spatial reuse, programmable connectivity, and increased network availability. The research agenda includes centralized analytical formulations that aim at optimizing the operation of the bottom three layers as well as distributed routing and medium access protocols that implement the outcomes of such optimization. Joint optimization of spectrum, transmission powers, and rates for CR communications will be considered in the presence of several primary (spectrum-licensed) radio networks (PRNs). No feedback from the PRNs will be assumed. Several formulations will be studied, which differ in the assumptions made on the channel dynamics (indirectly, user mobility), optimization window (packet vs. flow time scale), and availability or otherwise of power masks. Besides one-hop optimizations, the project will also consider multi-channel, multi-path optimizations at the packet and the flow time scales. The optimization results will then be integrated into the design of distributed channel access and path discovery/maintenance protocols for opportunistic CRNs. Depending on the frequency bands of interest, fixed power masks on CR transmissions may or may not be available. Protocols will be developed for both cases. In the absence of a fixed power mask, statistical modeling of PR interference will be conducted and used in the design of a MAC protocol that supports a probabilistic guarantee on the outage rate of PR receptions. The treatment will extend to both connectionless and connection-oriented applications. The cross-disciplinary nature of this project is expected to have a profound impact on many wireless technologies used in both civilian and military applications, including sensor networks, mesh networks, military radios, and wireless LANs. The optimization framework provides a general methodology that can significantly improve the performance, connectivity, and inter-operability of resource-constrained wireless networks in general.