Patent ID: 6890300

Claim:
A method for determining fluid pressure within a living animal containing the fluid under pressure which comprises: (a) providing a wireless capacitive MEMS chip sensor comprising an inductance coil (L) and spaced apart capacitor (C) plates as an inductive-capacitive (LC) circuit, with the fluid in the animal in pressure contact with one of the capacitive plates, wherein the circuit has an element which is a series resistance which changes as a function of temperature resulting in a change of a resonant frequency response of the circuit due to temperature; (b) inducing a mutual inductance as an external signal into the sensor to produce the resonant frequency response as an internal signal from the sensor; and (c) determining the fluid pressure and temperature within the animal externally of the animal from the internal signal as a function of the resonant frequency response from the sensor resulting from a change in capacitance of the sensor due to a variation in the spacing of the plates produced by the fluid pressure, and the temperature of the fluid from the sensor resulting from the change in the series resistance.