CAREER: Commutated-LC Circuits for Next-Generation RF-Domain Signal Processing

无线通信和传感已经无处不在。然而，随着无线技术的普及，电磁（EM）频谱变得越来越拥挤。新的概念和技术，如人工智能辅助的协作无线电网络，基于同时传输和接收的无线系统，以及大型天线阵列，已经出现，以有效地利用频谱，这就需要在射频（RF）领域进行信号处理。线性周期性时变（LPTV）开关电容电路在过去十年中得到了广泛的研究，因为它们可以在芯片上实现高质量、广泛可调谐和非互反的射频信号处理元件。然而，现有的LPTV电路基本上仅限于低阶、短延迟和低于6 GHz的操作。该项目通过引入新的整流电感-电容（整流- lc）电路，旨在解决现有开关电容电路的基本限制，这有可能大幅降低下一代无线系统的成本和尺寸，从而通过增加接入来造福社会。PI将在伊利诺伊大学厄巴纳香槟分校（UIUC）开发新课程，整合该项目的研究成果。此外，还计划与已建立的UIUC外展项目合作开发介绍性高中课程。PI在UIUC建立了电气和电子工程师协会（IEEE）固态电路分会，并将与其他教师和学生合作组织研讨会、短期课程和其他活动。在这个项目中，在整流电路中引入电感器或磁场，为现有的LPTV开关电容电路提供了新的自由度，在架构和组件级别上开辟了新的设计空间。该项目的智力价值在于对以下方面的知识和理解的进步：(1)工作频率超过6 ghz的高阶、长延迟换相lc电路的理论框架，(2)基于硅的换相lc电路实现的实际设计考虑，以及(3)开发下一代无线系统，该系统具有由换相lc电路实现的独特RF域信号处理能力。具体而言，该项目将研究用于可重构滤波前端的混合区域的换相lc电路，该电路覆盖更宽的频率调谐范围，在更高的RF下工作，并提供更陡峭的滤波器滚降。本文还将研究换相lc电路作为延迟元件的情况，以突破现有开关电容延迟中延迟频率积的限制。利用这种新的延迟组件，该项目将开发下一代同步发射和接收系统以及多元素天线阵列。最后，本课题将研究本振电路对换相lc电路在工作频率、噪声和功耗方面的影响。将开发具有低相位噪声和相位噪声消除技术的新型高频振荡器。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Wireless communications and sensing have become ubiquitous. With the proliferation of wireless technologies, however, the electromagnetic (EM) spectrum has become increasingly congested. New concepts and technologies, such as artificial intelligence assisted collaborative radio networks, simultaneous-transmission-and-reception-based wireless systems, and large antenna arrays, have emerged to efficiently utilize the spectrum, which necessitate signal processing in the radio frequency (RF) domain. Linear periodically time-variant (LPTV) switched-capacitor circuits have been studied extensively in the past decade as they enable high-quality, widely tunable, and non-reciprocal RF signal processing components on chip. However, existing LPTV circuits are fundamentally limited to low-order, short-delay, and sub-6 GHz operations. This project, by introducing new commutated-inductor-capacitor (commutated-LC) circuits, aims to tackle the fundamental limits of existing switched-capacitor circuits, which has the potential to substantially reduce the cost and size of next-generation wireless systems, thereby benefiting society through increasing access. The PI will develop new courses at the University of Illinois at Urbana Champaign (UIUC) that will integrate the research outcomes of this project. Introductory high-school-level curriculum development in collaboration with established UIUC outreach programs is also planned. The PI established an institute of electrical and electronics engineers (IEEE) Solid-State-Circuits chapter at UIUC and will organize seminars, short courses, and other events in collaboration with other faculty and students.In this project, the introduction of inductors or magnetic fields to commutated circuits provides new degrees of freedom to existing LPTV switched-capacitor circuits, opening new design spaces at both architecture and component levels. The intellectual merit of this project is in the advancement of knowledge and understanding related to (1) theoretical frameworks of high-order, long-delay commutated-LC circuits operating at beyond 6-GHz RF, (2) practical design considerations with silicon-based implementations of the commutated-LC circuits, and (3) development of next-generation wireless systems with unique RF-domain signal processing capabilities enabled by the commutated-LC circuits. Specifically, this project will investigate the commutated-LC circuits in the mixing region for reconfigurable filtering front-ends that cover a wider frequency tuning range, operate at a higher RF, and provide steeper filter roll-offs. It will also study the commutated-LC circuits when they are used as delay elements, targeting on breaking the limit of delay-frequency product in existing switched-capacitor delays. Leveraging this new delay component, this project will develop next-generation simultaneous-transmission-and-reception systems and many-element antenna arrays. Finally, this project will study the impact of local oscillator circuitry on commutated-LC circuits in terms of operation frequency, noise, and power consumption. New high-frequency oscillators with low phase noise and phase noise cancellation techniques will be developed.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.