RF Front-End Implementation Challenges of In-band Full-Duplex Relay Transceivers

JUAN COUSSEAU; GUSTAVO GONZALEZ; RISTO WICHMAN; FERNANDO GREGORIO; TANELI RIIHONEN

Oulu

Conferencia; 22th European Wireless Conference; 2016

University of Oulu

This paper presents a study on practical aspectsthat need to be considered in the implementation of in-bandfull-duplex wireless relay systems. Especially, the large powerlevel difference between the self-interference and the signal ofinterest is a key challenge for full-duplex transceivers. Self interference can be reduced by using a combination of passiveantenna isolation techniques and active analog RF or DSP basedcancellation techniques. In practice, a combination of thesetechniques is necessary to reduce the self-interference effectssuccessfully. Various RF impairments play a crucial role inthe performance of full-duplex communication and, thus, theyneed to be carefully addressed in order to guarantee successfulsystem operation. We study the effects of the most important RF impairments,such as IQ imbalance, phase noise, quantizationnoise from ADC converters and nonlinear distortion from poweramplifiers, on the performance of full-duplex relays.