Patent ID: 7848820

Claim:
A system for radio communication between an implantable medical device and an external base unit comprising: a first transceiver in said implantable medical device; a second transceiver in said external base unit, said first and second transceivers communicating with each other via a communication channel; a message generator in said external base unit that, according to a predetermined criterion, generates a sleep message and causes said sleep message to be transmitted to said implantable medical device via said first and second transceivers; power-consuming circuitry in said implantable medical device that, upon receipt of said sleep message, automatically switched to a sleep power down operational mode for a predetermined sleep time; disconnect circuitry in at least one of said implantable medical device or said external base unit that disconnects said communication channel in an absence of communication activity in said communication channel during a silent time period of predetermined length; said message generator in said base unit generating at least one standby message and causing said standby message to be communicated via said communication channel before expiration of said silent time period, to maintain said communication channel open between said base unit and said implantable medical device; and an acknowledgment unit in said implantable medical device that acknowledges receipt of said sleep message to said base unit via said first and second transceivers, but does not acknowledge receipt of said standby message.