Patent ID: 7409245

Claim:
An apparatus comprising: an implantable medical device including: an implantable transceiver; an implantable antenna, wherein an effective impedance of the antenna is variable dependent upon at least one of whether the antenna is implanted into a subject, a location at which the antenna is implanted into the subject, a body composition, and a body shape of the subject; a matching circuit, coupled to the antenna; an impedance mismatch detector circuit, coupled between the transceiver and the matching circuit, the impedance mismatch detector circuit configured to detect an indication of an impedance mismatch between said implantable transceiver in said implantable medical device and said implantable antenna; and a control circuit, coupled to the impedance mismatch detector circuit and the matching circuit, the control circuit configured to use the indication of the impedance mismatch as a control input to adjust the matching circuit in a manner that decreases the impedance mismatch and increases or maximizes a communication power transfer value associated with the implantable medical device.