CIF: Medium: Delay, Reliability, Rate Tradeoffs in Wireless Broadcast Channels

对我们的无线网络提出了更高的要求：它们不仅必须支持越来越多的语音和数据应用，其中数据速率是最重要的，而且无线网络还越来越多地用于延迟和可靠性敏感的技术，包括远程医疗、远程会议、交互式游戏，以及发送用于频谱共享的延迟敏感控制信息，实时能量管理，和自动驾驶汽车。然而，任意高的数据速率，低延迟和高可靠性不能同时实现在噪声和时变的无线信道。这项研究将寻求特征，在一个技术不可知的方式，在无线网络的最后一跳，其中一个基站希望传达独立的消息给许多用户的通信中的基本（延迟，可靠性，速率）权衡。研究结果将为实现这些雄心勃勃的目标的行业提供基本的性能基准和算法原型。该项目还寻求通过旨在提高入学率和参与度的学生从代表性不足的群体在computing.The（延迟，可靠性，率）权衡的活动扩大参与将从信息和通信理论的角度来表征。从信息论的角度来看，容量区域一直是中心焦点，其特征在于可以可靠地（具有极小的错误概率）同时传送给用户的消息的数量，因为信道使用的数量（以及因此延迟）趋于无穷大。这样的度量忽略了实际系统中存在的延迟约束。本研究的目的是描述一组消息，可以传达给每个用户在广播设置时，延迟是有限的，一个容忍一些错误。传输方案必须仔细重新考虑，以纳入这些延迟和可靠性约束，特别是当用户的信道随时间变化时，如在无线信道中。信息理论的研究将得到更实际的沟通理论的补充（延迟可靠性，率）的权衡（扩展了通信和网络社区中研究的简单擦除通道）该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准。

Greater demands are being placed on our wireless networks: not only must they support a growing number of voice and data applications where data rate is of prime importance, but wireless networks are also increasingly being used in delay- and reliability-sensitive technologies including tele-medicine, tele-conferencing, interactive-gaming, and sending delay-sensitive control information for spectrum sharing, real-time energy management, and autonomous vehicles. However, arbitrarily high data rates, low delays and high reliabilities cannot be achieved simultaneously over noisy and time-varying wireless channels. This research will seek to characterize, in a technology-agnostic manner, the fundamental (Delay, Reliability, Rate) tradeoffs in communications over the last-hop of wireless networks, where one base-station wishes to communicate independent messages to many users. The results will provide fundamental performance benchmarks and algorithmic prototypes for industries working towards these ambitious goals. The project also seeks to broaden participation through activities designed to increase enrollment and engagement of students from under-represented groups in computing.The (Delay, Reliability, Rate) tradeoffs will be characterized from information and communication theoretic perspectives. From an information theoretic perspective, the capacity region has long been the central focus, characterizing the number of messages that can be reliably (with vanishingly small probability of error) be communicated to the users simultaneously as the number of channel uses (and hence delay) tends to infinity. Such metrics ignore latency constraints present in practical systems. This research aims to characterize the set of messages that can be communicated to each user in a broadcast setting when the delay is finite and one tolerates some error. Transmission schemes must be carefully re-thought to incorporate these latency and reliability constraints, in particular when the channels to the users change over time as in a wireless channel. The information theoretic study will be complemented by more practically motivated communication theoretic (Delay Reliability, Rate) tradeoffs for the tractable multi-layer erasure channel (that extends simple erasure channels studied in the communications and networking communities) and then the practically relevant Gaussian fading broadcast channel.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.