Integrated Full-Duplex Radios: System Concepts, Implementations, and Experimentation

This chapter reviews recent research on integrated full-duplex (FD) radio systems using complementary metal oxide semiconductor (CMOS) technology. After a brief review of challenges associated with integrated FD radios, several CMOS FD radio designs, particularly those developed at Columbia University, are discussed with self-interference (SI) suppression at antenna interface, and in RF, analog, and digital domains. This chapter also reviews the system design and implementation of two generations of FD radios developed within the Columbia FlexICoN project (Columbia full-duplex wireless: From integrated circuits to networks (FlexICoN) project, https://flexicon.ee.columbia.edu) using off-the-shelf components and a software-defined radio (SDR) platform. The performance evaluation of these FD radios at the node- and link-level is also reviewed.