The Intersection of Radar and Communications: A Study on Spectrum Management for Addressing RF Interference

Abstract

The radio frequency (RF) spectrum is a fruitful yet competitive frontier that enables technologies like 5G, Wi-Fi, Bluetooth, GPS, long-range telescopes, microwave ovens, radar, and more. With finite supply and increasing demand, the RF spectrum is highly contested for both government and private use. Industry innovators need an increasing stake in the spectrum to keep up with modern data consumption needs, yet governments around the world require the same spectrum for important issues like national defense. This duality in demand often results in highly congested bands of frequency that host both stakeholders in dense configuration, increasing interference and difficulties in managing the spectrum. Interference of radar signals by communication waveforms, like orthogonal frequency division multiplexing (OFDM), is on the rise and can greatly impact system performance. This thesis introduces a novel interference mitigation algorithm that leverages the known structure of OFDM waveforms to estimate and subtract interference from a pulse-Doppler radar system. The proposed technique can significantly improve radar performance in the face of OFDM interference and quantify interference metrics to inform new regulations pertaining to spectrum management.