Blind Carbon Copy on Dirty Paper: Seamless Spectrum Underlay made Practical

从智能家居到智能汽车和高速公路，从智能医疗到精准农业，新兴技术很快就会要求数十亿无线设备实现无处不在的连接。对更多频谱的需求终于开始超过对频谱重复使用的抵制。目前存在引入创新频谱共享模式的强烈动力，这些模式能够提高频谱利用率和无缝共存，而不需要在遗留用户、科学用户、政府用户、军事用户和商业用户之间进行密切协调。SPECTRUM基准是实现这一目标的一个很有前途的范例。它提供在不干扰主用户的情况下运行的二次传输。然而，在不要求初级和次级系统密切协调的情况下实现这一点的实际手段仍然难以捉摸。该项目开发了实用的频谱底层解决方案，能够在以下情况下实现可靠的二次通信：在没有主-次协调或信道状态信息的情况下，在来自主系统的潜在强烈和时变干扰下进行可靠的二次通信。潜在的应用范围包括物联网(IoT)、车载和拥堵频谱区域的局域网(例如WiFi)网络。要确保美国在频谱研究、技术和商业/科学应用方面的领先地位，需要投资于频谱共享创新，并培养一支受过良好教育和多样化的频谱劳动力队伍。该项目为实现这两个目标作出了贡献。拟议的研究建立在首席研究员在统计信号处理、机器学习和矩阵理论以及实际通信工程方面的先前工作的基础上--这是培养和吸引董事会和实验室中不同的研究生和本科生的理想组合。这项研究将开发面向实际实施的最先进的理论和工程解决方案。这项工作的范围包括以下协同部分，以五种方式组织：1)将有限字母表和差错控制编码约束合并到基本代数框架中。T2)开发多路接入和随机交织解决方案，以使多用户环境中的多个次级传输“正交化”。T3)利用自适应调制和编码分析衰落场景下的性能。T4)解决关键的工程问题，即二次用户同步和模数转换，当二次信号比干扰一次信号弱得多时，这些问题是具有挑战性的。T5)开发软件无线电试验台并进行实验以验证建议的解决方案。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

From smart homes to smart cars and highways, and from smart health to precision agriculture, emerging technologies will soon demand ubiquitous connectivity for billions of wireless devices. The demand for more spectrum has finally started to outweigh resistance to spectrum reuse. There is currently strong impetus for introducing innovative spectrum sharing modalities that enable improved spectrum utilization and seamless cohabitation, without requiring tight coordination across legacy, scientific, government, military, and commercial users. Spectrum underlay is a promising paradigm towards this end. It provisions secondary transmissions that operate without disturbing the primary user. Practical means of accomplishing this without requiring tight coordination between the primary and the secondary system have remained elusive, however. This project develops practical spectrum underlay solutions which enable reliable secondary communication in scenarios where this would otherwise seem untenable: without primary-secondary coordination or channel state information, under potentially strong and time-varying interference from the primary system. The scope of potential applications includes Internet of Things (IoT), vehicular, and local area (e.g., WiFi) networks in congested spectrum areas.Ensuring United States leadership in spectrum research, technologies, and commercial/scientific applications requires investments in spectrum sharing innovations and developing a well-educated and diverse spectrum workforce. This projects makes contributions towards both of these goals. The proposed research builds upon the principal investigator's prior work on statistical signal processing, machine learning, and matrix theory, as well as practical communications engineering -- an ideal combination to educate and engage diverse graduate and undergraduate students on the board and in the lab. The research will develop state-of-the-art theory and engineering solutions geared towards practical implementation. The scope of the work includes the following synergistic components, organized in five thrusts: T1) Incorporating finite alphabet and error control coding constraints into the basic algebraic framework. T2) Developing multi-access and random interleaving solutions to ``orthogonalize'' multiple secondary transmissions in multiuser settings. T3) Analyzing performance under fading scenarios, with adaptive modulation and coding. T4) Addressing key engineering issues, namely, secondary user synchronization and analog-to-digital conversion, which are challenging when the secondary signal is much weaker than the interfering primary signal. T5) Developing a software radio testbed and conducting experiments to validate the proposed solutions.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.