Advanced multi-user systems for wireless communication networks

对具有诸如语音、电子邮件和交互式多媒体的差异化服务的无处不在的宽带无线接入的日益增长的需求是无线通信技术进步的关键驱动力。在无线链路的一端或两端处的多个天线的可用性提供了链路的可实现速率和可靠性的实质性增加的潜力，并且因此这些多输入多输出（MIMO）系统以某种形式出现在用于未来无线通信系统的几乎所有提议的物理层中。然而，无线介质基本上是一个共享环境，具有固有的广播能力，但也相互干扰。如果无线网络（或多个网络）的物理层被设计为利用环境的共享性质，则可以更有效地使用由环境提供的通信资源，这与独立地优化每个链路的性能不同，并且如果它动态地这样做。在具有某种形式的集中控制的网络（诸如单小区系统的上行链路和下行链路）和其中控制是分布式的网络（诸如协作通信系统、频谱覆盖（“认知”）系统和自组织网络）的情况下，资源的这种动态分配提供了可以提供的服务质量的实质性增加的潜力。拟议的研究计划的目标是开发计算效率的设计技术，使无线网络，使多用户收发器，有效地利用现有的资源。由此产生的系统将构成未来无线网络愿景得以实现的一些基石。设计技术的发展将由多用户信息理论和优化的见解（和贡献）指导，设计的实现将利用“软件无线电”收发器架构提供的灵活性。工作的重点将是基本设计原则的发展，但这些原则的专业化可以应用于特定标准机构或公司开发的系统。

The increasing demand for ubiquitous broadband wireless access with differentiated services, such as voice, email, and interactive multimedia, is a key driving force for advances in wireless communication technologies. The availability of multiple antennas at one or both ends of a wireless link provides the potential for substantial increases in the achievable rate and the reliability of the link, and hence these multiple-input, multiple-output (MIMO) systems appear, in some form, in the physical layer of almost all proposals for future wireless communication systems. However, the wireless medium is fundamentally a shared environment, with an inherent broadcast capability, but also mutual interference. The communication resources provided by the environment can be used more efficiently if the physical layer of the wireless network (or networks) is designed to take advantage of the shared nature of the environment, as distinct from optimizing the performance of each link independently, and if it does so dynamically. This dynamic allocation of resources offers the potential for a substantial increase in the quality of service that can be offered, both in the case of networks with some form of centralized control, such as the uplink and downlink of single-cell systems, and networks in which control is distributed, such as cooperative communication systems, spectral overlay ("cognitive") systems, and ad-hoc networks. The goal of the proposed research program is to develop computationally-efficient design techniques for multi-user transceivers that enable wireless networks to make efficient use of the available resources. The resulting systems will form some of the building blocks with which the visions of future wireless networks will be realized. The development of the design techniques will be guided by insights from (and contributions to) multi-user information theory and optimization, and the implementation of the designs will take advantage of the flexibility provided by the "software radio" transceiver architecture. The focus of the work will be on the development of fundamental design principles, but specializations of these principles could be applied to systems developed by particular standards bodies or companies.