The past decade has witnessed a skyrocketing demand for commercial wireless spectrum. These sharp increases in mobile traffic (particularly smartphone traffic) are projected to continue in the foreseeable future, creating an urgent need to develop innovative spectrum sensing and sharing technologies. The proposed research is inspired by Waze, a highly successful GPS-based mobile navigation application program that provides real-time traffic information, based on user-submitted travel times and route details. Inspired by Waze, this project is centered around the vision that future generation smartphones will be able to carry out real-time spectrum sensing and sharing of the communication environment, through built-in spectrum sniffers and the help of shared usage information from mobile devices. This research shall enable a paradigm shift from existing cognitive radio design approaches to usage aware spectrum sharing. Innovative implementation of a low-cost integrated broadband RF design for smartphone spectral sniffing, in combination with novel spectrum sharing techniques, will have a compelling and transformative impact in smartphone design and enable efficient spectrum sharing. The educational activities will develop skilled workforce in this area of national need by inspiring and engaging the middle and high school student population in engineering.
Built on this vision, this project advocates joint design of radio frequency (RF) hardware and spectrum sensing for smartphones, aiming to enable usage-aware spectrum sharing with minimal dynamic range and power consumption requirements placed on the smartphone hardware. Under this common theme, this project consists of the following research and educational thrusts. I) Low-cost RF architecture for smartphone sensing. Thrust I focuses on low-cost, integrated, broadband RF design for spectrum sensing and data transmission. The spectral sniffer leverages shared usage information to detect RF signals from 1 GHz to 18 GHz with both high dynamic range and sensitivity, and the digital transmitter enables modulation-agnostic data transmission with low handset power consumption. Built on the low-overhead design of RF hardware in this thrust, database assisted spectrum access and distributed spectrum access are explored in Thrusts II and III, respectively. II) Waze-inspired database assisted spectrum sharing. Along the same line as in the Waze application, a database is used to gather spectrum usage information from smartphones, and sends both real-time location-specific usage information and the set of potentially vacant channels in response to the requests from individual users. Each user then carries out refined sensing, followed by data transmissions. III) Waze-inspired usage-aware distributed spectrum sharing. Thrust III is dedicated to study distributed spectrum sharing, where usage information is shared only among smartphone users in the vicinity. IV) Integrate research into education and outreach by performing a diverse set of activities that include curricular tasks and K-12 outreach.