Systems and techniques for adaptive interference filtering in a communications device are disclosed. The communications device may include a transmitter, a receiver, a duplexer coupled to the transmitter and the receiver, and an adaptive filter disposed between the duplexer and the receiver. A processor may be configured to monitor cross modulation in the receiver between transmitter leakage through the duplexer and a jammer, and adapt the filter to vary its transmit signal rejection as a function of the cross modulation.