Implantable medical devices and techniques are implemented that use bio-impedance to measure aspects of patient physiology. A signal separation method is performed at least in part in an implantable device. The method involves detecting a plurality of impedance signals using a plurality of implantable...http://www.google.com/patents/US20070142733?utm_source=gb-gplus-sharePatent US20070142733 - Bio-impedance sensor and sensing method
