GBSense: GHz Bandwidth Sensing from Smart Antennas to Sub-Nyquist Signal Processing

在过去十年中，人、机器和事物之间交换移动信息的数据速率呈指数级增长。根据经验，这些数据速率与无线电频谱可用性有关。高昂的拍卖价格，例如英国4G频谱的23亿英镑，突显了竞争市场力量的力量，但也凸显了这种宝贵资源的稀缺性。在频谱稀缺的推动下，英国通信监管机构（Ofcom）于2016年1月在超高频（UHF）电视频段上进行了创新的免许可证频谱共享，这在全球范围内尚属首例。这些320MHz带宽的频谱使认知无线电理论研究向实际应用过渡。此外，正在考虑进一步统一28GHz、39GHz、60GHz以上带宽的毫米波频谱，以满足用户对高数据速率无线应用和业务的需求。卫星和雷达应用在这些毫米波频谱中共存，因此，任何豁免许可证的频谱使用都必须首先确定所使用的频谱尚未被所谓的“主要用户”使用。因此，从UHF的数百MHz带宽到毫米波的GHz带宽的传感以获得对这些频谱的清晰访问至关重要，同时对奈奎斯特速率模数采样带来了巨大而复杂的挑战。该奖学金项目提出了一种设计GHz带宽传感（GBSense）系统的新方法，通过开发亚奈奎斯特采样算法和重新利用现有智能天线和可重构传输线的专业知识，克服奈奎斯特速率采样的瓶颈。GBSense在实时实验平台框架上提供了新的创造性和可实现的可能性，而不需要奈奎斯特速率采样。GBSense为用户提供了一个灵活的硬件平台和应用软件，可以在6ghz以下和毫米波频段实现实时的空中GHz带宽信号传感、分析和通信。它还将与一个低成本的计算单元，如树莓派接口，其中亚奈奎斯特算法托管，实现更好的人机交互和推进亚奈奎斯特采样理论的现有知识，并给软件和硬件工程师带来一系列新的挑战。研究结果将通过研讨会、变革竞赛、开源计划和外联活动向软件和硬件学术研究人员、工业界和公众传播。

Data rate for exchanging mobile information among people, machines and things has been exponentially increasing over the past decade. These data rates are empirically linked to radio spectrum availability. The exorbitant auction prices, e.g., £2.3 Billion for 4G spectrum in the UK, highlights the strength of the competitive market forces but also the scarcity of this precious resource. Driven by the scarcity of spectrum, the UK communications regulator (Ofcom) has made an innovative licence-exempt spectrum sharing on the ultra-high frequency (UHF) TV bands in January 2016, which is the first of its kind worldwide. These spectra of 320MHz bandwidth have enabled the transition from research on cognitive radio theory into practical applications. Furthermore, the millimetre-wave (mm-wave) spectrum on 28GHz, 39GHz, 60GHz with at least 1GHz bandwidth are being considered to be further unitised to cope with high data rate wireless applications and services demanded by users. The satellite and radar applications are co-existing in these mm-wave spectra, and thus any licence-exempt use of this spectra must first ascertain that the spectra to be used is not already in use by the so called "primary users". Therefore, sensing from several hundreds of MHz bandwidth in UHF to GHz bandwidth in mm-wave to gain a clear access to these spectra is critical, while resulting in formidable and complex challenge on the Nyquist-rate analog-to-digital sampling.This fellowship project proposes a new approach to design GHz bandwidth sensing (GBSense) systems to overcome the bottleneck of Nyquist-rate sampling by developing sub-Nyquist sampling algorithms and repurposing the existing expertise of smart antennas and reconfigurable transmission lines. The GBSense offers new creative and implementable possibilities over a framework of real-time experimental platform without requiring Nyquist-rate sampling. The GBSense gives users access to a flexible hardware platform and application software that enables real-time over the air GHz bandwidth signal sensing, analysis and communication at both sub-6GHz and mm-wave frequency bands. It will also interface with a low-cost computing unit, e.g., Raspberry PI, where sub-Nyquist algorithms are hosted, for enabling better human-computer interaction and advance the current knowledge in sub-Nyquist sampling theory and bring a new set of challenges to both software and hardware engineers. Results will be disseminated to both software and hardware academic researchers, industry and the public through workshops, change-led competitions, open-source plans and outreach activities.