CIF: Medium: Collaborative Research: On-demand Physical Layer Cooperation

无线接入正迅速成为互联网的主要门户，导致对无线数据的需求呈指数级增长。 尽管为了满足不断增长的需求而对基础设施进行了大量投资，但这已经将当前的无线系统推向了极限。物理层协作可以实现可用无线带宽的近乎最佳使用。该提案通过引入无线协作的按需方法从根本上重新考虑了物理层协作。可以说，（有线）互联网的成功是通过其按需运营、利用适应性、本地知识、反馈和尽力而为的服务模式而得以实现的。值得注意的是，许多对等网络协议的成功与按需信息传播和网络适应密切相关。该提案的总体目标是将这一理念引入无线网络，从而在可实现系统的复杂性限制内实现无线网络带宽的近乎最佳使用。该项目旨在通过软件无线电测试台上的概念验证部署来补充理论工作，并让行业合作伙伴参与影响下一代无线网络设计。 该项目还通过建立独特的大学间教育和研究计划的计划来促进研究工程师的培训，其中包括联合和协作的学生咨询和课程开发。大多数网络信息理论工作的基本假设是，人们可以构建能够在非常快的时间尺度上紧密协调有关无线信道、用户需求和网络拓扑的信息的估计和共享的架构，而不影响性能（速率、错误）。也就是说，没有考虑学习非常动态的网络状态的成本。另一个隐含的假设是完整的网络使用，即使用无线网络中的所有可用中继，而不适应用户需求。在许多情况下，这可能非常浪费，并且没有考虑到不必要地使用继电器的成本。基于这些假设的许多突破性想法促进了集体理解，但使物理层协作技术更接近实际网络需要采取额外的步骤来超越这些假设。该项目整合了一个程序，该程序开发了按需网络操作的理论基础和实践，而无需这些假设。这需要操作满足目标速率的网络中继的特定子集（子网），而不是使用所有网络中继来实现最佳性能。该项目通过使用可靠的部分网络知识并使用反馈机制来增强信号对未知的适应，构建了如何按需选择、适应和操作这些子网络的理论理解。理论公式与将在测试台中验证的可实施协议紧密结合。

Wireless access is fast becoming the primary portal to the Internet, causing an exponentially rising demand for wireless data. This has pushed current wireless systems to their limits, despite significant investment in infrastructure to meet the ever-growing demands. Physical layer cooperation can enable near-optimal usage of the available wireless bandwidth.This proposal fundamentally rethinks physical-layer cooperation by introducing an on-demand approach to wireless cooperation. It can be argued that the success of the (wired) Internet was made possible by its on-demand operation, using adaptation, local knowledge, feedback and a best-effort service model. Notably, the success of many peer-to-peer network protocols is closely tied to on-demand information propagation and adaptation of the network. The broad goal of this proposal is to bring this philosophy to wireless networks, enabling near-optimal usage of the wireless network bandwidth within the complexity constraints of implementable systems. This project aims to complement the theoretical work with proof-of-concept deployments on software radio testbeds, and also engage industry partners to impact next-generation wireless network designs. The project also promotes training of research engineers, through a plan to establish a unique inter-university education and research program, which will include joint and collaborative student advising and curricular development. The underlying assumption of most network information theory works is that one can build architectures which tightly coordinate the estimation and sharing of information about the wireless channels, the user requirements and the network topology, at a very fast time-scale, without impacting the performance (rates, error). That is, the cost of learning the very dynamic network state is not accounted for. Another implicit assumption is complete network usage, that all available relays in a wireless network are used, with no adaptation to user demand. This can be very wasteful in many situations, and again, the cost of unnecessarily using relays is not accounted for. The many breakthrough ideas based on these assumptions have advanced a collective understanding, but bringing physical layer cooperation techniques closer to practical networks requires additional steps to move beyond these assumptions. This project puts together a program that develops the theoretical foundations and practice of an on-demand network operation, that dispenses with these assumptions. This entails operating specific subsets of the network relays (sub-networks) that fulfill target rates, as opposed to using all network relays to achieve the best possible performance. This project constructs a theoretical understanding of how to select, adapt and operate these sub-networks on demand, by using accountable partial network knowledge and using feedback mechanisms to enhance signal adaptation to the unknown. The theoretical formulations are tightly coupled to implementable protocols that will be validated in test beds.