Mitigating self-interference between a device transmitter and receiver

Mitigating self-interference between transmitters and receivers in a multifunction radio device (such as a mobile telephone) including a transmitter operating in a first frequency band having a plurality of channels and a receiver operating in a second, different frequency band having a predetermined sensitivity. Jamming factors for each frequency channel in the first frequency band are calculated based on possible interference with the second frequency band by artefacts of the respective frequency channels. The frequency channel having the smallest jamming factor is selected as the frequency to be used by the transmitter.