A two-stage analog cancellation architecture for self-interference suppression in full-duplex communications

In this paper, a two-stage analog interference cancellation architecture is proposed for the prevailing full-duplex communication systems. Within the architecture, a one-tap analog cancelling circuit is first deployed to reconstruct and cancel the strong leakage self interference (SI) to yield a residual multi-path SI of reduced dynamic range. Subsequently, an auxiliary transmit chain is deployed to particularly reconstruct and cancel the residual multi-path SI components, to further improve the overall analog cancellation performance. Experimental results have validated the superior analog cancellation performance of this architecture on wide-band long-term evolution signals.