WINLAB Team receives NSF Grant for Enabling Next Generation Terrestrial Wireless Network Coexistence with Active and Passive Satellite Systems

A team of WINLAB researchers led by Distinguished Professor Narayan Mandayam (PI) along with co-PIs Ivan Seskar (Chief Technologist, WINLAB) and Chung-Tse Michael Wu (Associate Professor, ECE), are the recipients of an award from the National Science Foundation under the Spectrum and Wireless Innovation enabled by Future Technologies- Satellite-Terrestrial Coexistence (SWIFT-SAT) program for the project "Software Defined Radio based Emulation of SAT-Terrestrial Network Coexistence in "FR3" Bands." This three-year project funded at $750,000 addresses an emerging topic of increasing interest, namely the opening up of new spectrum for terrestrial communications that allows coexistence with satellite uses such as: (i) commercial digital video broadcast (e.g. DIRECTV, DISH Network); and (ii) passive earth observation and sensing. 

 

Currently, the 5G spectrum includes Frequency Range 1 (FR1) below 7.125 GHz that is overcrowded, and Frequency Range 2 (FR2) covering mmWave bands between 24 and 52.6 GHz that is limited in coverage, due to challenges in deploying mmWave technology.  However, emerging use cases demand even higher data rates and lower latency, necessitating additional spectrum. Frequency Range 3 (FR3) bands between 7.125 and 24 GHz are promising for next generation terrestrial systems owing to their favorable propagation characteristics.  However, these systems must coexist with active commercial (e.g. digital broadcast) and passive earth observation (e.g. weather forecasting) satellite (SAT) services. Existing coexistence studies rely on modeling and simulations, lacking direct measurements or testbed-based emulation. This project develops software-defined radio (SDR)-based testbeds to study SAT-terrestrial network coexistence in the FR3 bands, by emulating dense 5G network and SAT coexistence enabled by machine learning (ML), specifically focusing on 12.2-12.7 GHz for active SAT coexistence and 10.6-10.7 GHz for passive SAT sensor coexistence. Leveraging the COSMOS sandbox at WINLAB, an SDR network is designed to emulate 5G radio networks, SAT transceivers, and passive radiometers in the targeted frequency bands. The research focuses on three key thrusts: (1) designing SDR-based heterodyne systems to emulate 5G New Radio (NR) and SAT waveforms, including metamaterial software-defined beamforming for studying coexistence between 5G terrestrial networks and active SAT systems like non-geostationary orbit fixed satellite service (NGSO-FSS); (2) developing integrated radio resource management strategies for spectrum coexistence in the 12.2-12.7 GHz through novel SDR-based network emulation and centralized spectrum server ML algorithms; and (3) emulating spectrum coexistence between 5G terrestrial networks and passive sensors on earth observation satellites, analyzing the sensitivity of passive radiometers to radio frequency interference (RFI) and developing ML algorithms for RFI identification and mitigation. The loss in “available" spectrum resulting from mitigation strategies enabling peaceful coexistence with SAT systems, is quantified. The creation of the FR3 testbed is valuable to the scientific community, accessible as an open resource fostering innovation and collaboration among researchers and industry professionals.