AM/FM Multi-Channel Implantable/Ingestible Bio-Medical Monitoring Telemetry System

Reference#: P01183

A multi-channel circuit for telemetering signals representing physiological values from a point in a human body to a receiver outside of the body. The two signals other than the temperature signal are used to provide two frequency modulated signals summed by an amplifier with the summed FM signal then being applied to amplitude modulate a carrier whose frequency varies as a function of temperature. The resulting FM/AM signal is telemetered inductively outside of the body to an external receiver. Appropriate demodulation, filter, and shaping circuits within the external circuit detect the FM signals and thus produce three independent frequencies two of which are the original physiological variables and the third a function of local temperature. Real time plot of the two physiological variables can be obtained using FM discriminators while the temperature dependent frequency is best monitored by a counter.

Mr. E. Chalfin
Phone: (443) 778-7473