Full-duplex self-interference mitigation performance in nonlinear channels

In-band (cochannel) full-duplex multiple-input multiple-output (MIMO) radios with antenna reuse employ an array of antennas to provide potentially significant improvements in radio throughput and in network latency. Each antenna transmits and receives simultaneously. One of the most significant challenges is the mitigation of the radio´s self-interference. While there are a variety of issues that limit self-interference mitigation, here we focus on low-order nonlinearities. We employ a temporal mitigation strategy, expressed as a projection operator, that includes the effects of the nonlinearities. We also discuss extensions to the approach for passband (RF) mitigation. To simplify the discussion, we assume quasistatic flat-fading channels.