NSF Award
2434020
Demand for spectrum has increased tremendously over the last decades, making the available spectrum a scarce and valuable resource. However, for a variety of reasons, spectrum has traditionally been managed in an inflexible manner, a situation that exacerbates this scarcity and results in undesirable behaviors of those that have access to spectrum. This creates a potential to stifle the incredible innovation and economic impact that wireless systems have created in the last 40 years, which presents a risk to the economy and potentially could result in disruptions to critical communication, radiolocation, public safety and defense services. To move forward, a radically more flexible paradigm is needed. And while the last few decades have seen great innovation in radio design and even in spectrum policy, the current inflexible management model has hamstrung everything. This project proposes a vision of a new spectrum era that relies on adaptivity and reconfigurability as its core elements. Adaptivity and reconfigurability must be used from the components on the device all the way through to the policies that govern the interactions of many systems. This concept can be envisioned similar to driving on roadways. Protocols and policies (road rules) are needed that enable real-time spectrum sharing in a mutually beneficial way for all involved users. A Spectrum Sharing and Management System, paralleling law enforcement officers and traffic signals, must be developed for real-time coordination between devices in more congested scenarios where collisions are likely if autonomous operation remains. Devices, circuits, and systems are required that can reconfigure their systems to automatically optimize performance upon changing operation to different spectrum.<br/><br/>This proposed project will be the first demonstration of the capacity to directly map a set of desirable system metrics (e.g., frequency, bandwidth, beam pattern, power, impedance, etc.) to a nearly arbitrary layout of light-activated plasma pixel antenna radiators. The key enabling technology is a semiconductor plasma pixel phased array with the unprecedented ability to create nearly-arbitrary-shaped radiators, including the elimination of the radiators altogether. The key attributes include: (a) a pixel-by-pixel adaptive geometry using light-activated plasma pixel radiators, (b) reconfiguration at high speed, high linearity, and with high power handling, (c) ‘painting’ the system-informed radiator profile over a fixed feeding network, and (d) fast optimization approaches informed by Artificial Intelligence (AI) and Machine Learning (ML) to create array configurations mapped to desired radar resolutions, system performance, and dynamically imposed spatial-spectral limitations. The primary objectives include the following: (1) develop the plasma phased array focusing on feed network solutions, and (2) develop fast AI/ML supported reconfiguration algorithms to enable the integrated system performance-to-radiator mapping in real time. Broader outcomes of the proposed project include: (1) wireless and spectrum engineering education for high school students, (2) presentation of results at workforce development events including the NSF-funded “Spectrum Sizzle” Undergraduate Spectrum Workshop, (3) contribution to workshops and special sessions at international conferences engaging spectrum stakeholders, (4) integration of the multidisciplinary research topics and findings into microwave and computational intelligence courses, and (5) a commitment to promoting diversity in research teams and outreach programs to underserved schools to foster interest in STEM related fields.<br/><br/>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.
