US Patent 7519430 Dynamic telemetry encoding for an implantable medical device

A telemetry system provides a selectable encoding protocol, including, for example, a plurality of redundancy levels, where the encoding protocol is selected based on a measure of transmission efficiency. For example, later messages are transmitted using an increased redundancy if a prior message exhibits a low signal to noise ratio. A communication session is initiated using a first level of redundancy and the level is adjusted based on a channel characteristic or a measured parameter.