External instruments and implantable medical devices communicate using modulation parameter settings that may be adapted during communication sessions based on a quality of the wireless communications link. An analysis of the quality of the link is performed and a request to change modulation parameters is sent to one of the devices by the other. The analysis may be based on measuring noise and interference during idle communication frames. The devices may then change the modulation parameter settings, for the uplink, downlink, or both. The devices may also employ a recovery operation to revert back to the previous modulation parameter settings if the transmissions are not properly received using the changed modulation parameter settings. The modulation parameter settings may include modulation type, modulation symbol rate, and the like.
