CAREER:Active Nano-Acoustic Waveguide Matrix to Tackle Signal Processing Limits: Enabling Wideband and Nonreciprocal Integrated Communication Beyond the UHF

无线技术通过支持现代社会的基础设施，包括智能交通系统，物联网，智能制造和互联医疗保健，有望彻底改变人类生活的各个方面。为了实现这样的革命，迫切需要极大地提高稀缺的无线电频谱资源及其使用效率。有效利用无线电频谱对于满足从国家安全和公共安全到交通、广播和商业服务等各种社会需求至关重要，并在持续经济增长中发挥决定性作用。对无线电频谱资源的无线接入目前受到仅在频谱的低端有效的可用信号处理硬件的限制;因此，迫使诸如智能电话、平板电脑和全球定位系统（GPS）的当前无线系统在非常有限的频率范围（即，超过~0.3-6 GHz）中操作。如此小的频率范围已经过于拥挤，无法容纳新的无线用户或需要超快数据通信的设施。此外，可用的硬件基本上不能在相同的频带中并且在相同的时间进行同时的数据发送和接收。因此，当前的无线系统被迫占用单独的频带用于数据传输和接收;因此，将频谱使用效率减半。拟议的研究目标是通过开发一种变革性的单晶锗（Ge）纳米声学技术，超越当前集成信号处理器的基本局限性，该技术1）在整个超高频和极高频范围内有效运行（即，3-300 GHz），以及2）通过根本上不同的操作物理，使得能够在相同频带中并且同时进行同时数据发送和接收;从而使频谱使用效率加倍。研究内容包括：（1）研究半导体中的纳米声波波导，重点是单晶Ge，用于超高频范围以外的宽带信号处理（UHF：0.3-3GHz）;（2）通过压电-半导体纳米声波波导中的声电效应探索弹性信号的有源电子放大的物理学/科学;（3）UHF以上低损耗和宽带信号处理器的设计和演示;（4）芯片级非互易信号处理器的工程设计，重点是隔离器和环行器。与研究相结合，该项目的目标是通过教育工具包和高中课程丰富关于新型纳米机电系统及其在日常生活中不可或缺的作用的社会知识，并通过女性和少数民族学生的参与增强跨学科科学，技术，工程和数学（iSTEM）研究和职业的多样性。

Wireless technologies are poised to revolutionize all aspects of human life through enabling the infrastructures of a modern society, including intelligent transportation systems, internet of things, smart manufacturing, and connected healthcare. To enable such a revolution, there is a pressing need for tremendous enhancement of the scarce radio spectrum resources and their use efficiency. The effective access to radio spectrum is crucial for a diverse span of social needs ranging from national security and public safety to transportation, broadcasting and commercial services and plays a decisive role in continuous economic growth. The wireless access to radio spectrum resources is currently limited by the available signal processing hardware that are only efficient in the lower end of the spectrum; hence, forcing current wireless systems such as smart phones, tablets and global positioning systems (GPS) to operate in a very limited frequency range (i.e. over ~0.3-6 GHz). Such a small frequency range is already overcrowded and cannot accommodate new wireless users or amenities that require ultra-fast data communication. Furthermore, available hardware are fundamentally incapable of simultaneous data transmission and reception in the same frequency band and at the same time. Therefore, current wireless systems are forced to occupy separate bands for data transmission and reception; hence, cutting the efficiency of the spectrum use in half. The proposed research targets surpassing the fundamental limitations of current integrated signal processors through development of a transformative nano-acoustic technology in single crystal germanium (Ge) that 1) operates efficiently over the entire super- and extremely-high-frequency regimes (i.e. 3-300 GHz), and 2) enables simultaneous data transmission and reception in the same frequency band and at the same time, through fundamentally different operation physics; hence, doubling the spectrum use efficiency. Research shall consist of (1) investigation of nano-acoustic waveguides in semiconductors, with a focus on single crystal Ge, for wideband signal processing beyond the ultra-high-frequency regime (UHF: 0.3-3GHz); (2) exploration of the physics/science of active electronic amplification of elastic signals through the acoustoelectric effects in piezoelectric-semiconductor nano-acoustic waveguides; (3) design and demonstration of low-loss and wideband signal processors beyond the UHF; and (4) engineering of chip-scale nonreciprocal signal processors, with a focus on isolators and circulators. Integrated with the research, this project targets the enrichment of social knowledge on novel nano-electro-mechanical systems and their indispensable role in everyday life through educational kits and high-school curriculum, and enhancement of diversity in interdisciplinary Science, Technology, Engineering and Math (iSTEM) research and careers through involvement of female and minority students.