CIF:Small: Collaborative Research:Theoretical Foundation of Distributed Wireless Channel Access

由于缺乏对如何在空间分布的用户之间共享无线媒体的基本理解，无线网络的能量消耗和带宽效率仍然是低效的和高度次优的。先前的调查无线信道接入遵循两个独立的路径，反映了截然不同的观点，即，传统的信息理论的方法假设完美的用户协调，忽略了模块化的网络架构，而传统的网络理论的方法主要集中在访问控制协议，忽略了物理层的影响。本计画将借由建立分散式无线系统中通道存取的理论基础，来弥补传统理论的差距。更具体地说，它将扩展经典的信息理论，通过开发一个信道编码理论的物理层分布式通信，用户不联合设计信道码。它还将扩展经典的网络理论，通过开发一个分布式网络的介质访问控制（MAC）框架，其中物理层的属性，如联合多用户消息解码和灵活的通信参数的自适应，有效地利用在链路层。在项目的第一部分，目标是开发一个严格的编码理论来描述分布式通信系统的基本局限性。编码理论将支持广泛的通信性能权衡和低计算复杂度的结构化编码方案。该项目的第二部分包括三个步骤。第一步的目标是表征最佳的链路层分布式信道共享方案，其基本属性和性能改进经典计划。第二步的目标是开发一个统一的MAC框架，以通过通信参数（例如，速率、功率、传输概率）。第三步的目标是开发具有快速收敛特性的MAC算法，以确保网络在瞬态环境中的有效运行。通过将信息理论扩展到分布式通信模型，该项目将促进信息和网络理论的融合，并显着提高无线系统的能量和带宽效率。这两个经典理论的统一也将影响现代通信网络学科在高等教育中的教学方式，并吸引更多有才华的学生进入这一具有国家重要性的领域。

Due to lack of fundamental understanding on how to share wireless media among spatially distributed users, the energy consumption and bandwidth efficiency of wireless networks remains defficient and highly suboptimal. Prior investigations of wireless channel access have followed two separate paths that reflect vastly different viewpoints; namely, the traditional information-theoretic approach assumes perfect user coordination and ignores the modularized network architecture, while the traditional network-theoretic approach largely focuses on access control protocols and ignores the impact of the physical layer. This project will bridge the gap of the classical theories by developing a theoretical foundation for channel access in distributed wireless systems. More specifically, it will extend classical information theory by developing a channel coding theory for physical layer distributed communication, where users do not jointly design channel codes. It will also extend classical network theory by developing a medium access control (MAC) framework for distributed networking, where physical layer properties, such as joint multiuser message decoding and flexible adaptation of communication parameters, are efficiently exploited at the link layer.The project contains two parts which respectively address the physical and the data link layers of distributed wireless networks. In Part I of the project, the goal is to develop a rigorous coding theory to characterize the fundamental limitis of distributed communication systems. The coding theory will support extensive communication performance tradeoffs and structured coding schemes with low computational complexity. Part II of the project contains three steps. The objective of the first step is to characterize optimal link layer distributed channel sharing schemes, their fundamental properties and performance improvements over classical schemes. The objective of the second step is to develop a unified MAC framework to achieve asymptotic optimal channel sharing in distributed networks via the joint adaptation of communication parameters (e.g., rate, power, transmission probability). The objective of the third step is to develop MAC algorithms with fast convergence properties that ensure efficient network operation in transient environments.By extending information theory to distributed communication models, the project will advance the integration of information and network theories, and significantly improve the energy and bandwidth efficiency of wireless systems. Unification of the two classical theories will also influence the way modern communication network subjects are taught in Higher Education and attract more talented students to this field of acute national importance.