Implantable device telemetry with adaptive frequency hopping

A far-field radio-frequency (RF) telemetry system transmits data between an implantable medical device and an external system using an active channel selected from a plurality of channels each representing a frequency band within a predetermined frequency range. One or more preferred channels are identified from the plurality of channels based on channel quality indicators produced for each of the channels. When channel hopping is needed, a hop channel is selected from the one or more preferred channels and becomes the active channel.