Self-Interference Cancellation Limits in Full-Duplex Communication Systems

A good self-interference (SI) cancellation strategy in full-duplex (FD) communication passes first by a proper understanding of the nature of this SI. In this paper, we investigate the basic causes of SI cancellation bottlenecks in FD. To that end, we first classify the known FD architectures based on where the reference signal is taken to cancel the SI. By combining the effects of transceiver impairment, estimation error and SI channel, our analysis reveals that the the main bottleneck to completely cancel the SI turns out to be either the quantization-noise, the phase-noise in the local oscillator or the estimation error, depending on the used architecture.