Full-duplex Wireless with Large Antenna Arrays

Abstract

To meet the growing demand for wireless data, base stations with very large antenna arrays are being deployed in order to serve multiple users simultaneously. Concurrently, there is growing interest in full-duplex operation. The challenge to full-duplex is suppressing the high-powered self-interference caused by transmitting and receiving at the same time on the same frequency. Unfortunately, the state-of-the-art methods to suppress self-interference require extra analog circuitry that does not scale well to large antenna arrays. However, large antenna arrays open a new opportunity to use digital beamforming to reduce the self-interference. In this thesis we study the use of digital beamforming to enable full-duplex operation on conventional antenna arrays. Unlike most designs that rely on analog cancelers to suppress self-interference, we consider all-digital solutions that can be employed on existing radio hardware.