Patent ID: 6775632
Filing Date: 2004-08-10
Classification: B60C,G01K,G01L

Abstract:
Method of calibrating an RF transponder that measures temperature and pressure in a monitored object, comprising:in a calibration chamber, exposing the transponder to a number of predetermined temperatures and pressures at a number of calibration points; at each calibration point, transmitting from the transponder a calibration temperature reading which is a function of temperature sensed by the transponder; at each calibration point, transmitting from the transponder a calibration pressure reading which is a function of both pressure and temperature sensed by the transponder; and calculating a number of calibration constants for use in equations which characterize the temperature and pressure responsiveness of the transponder; the method characterized in that: there are at least three calibration points; a fist calibration point of the at least three calibration points is at a first temperature and a first pressure; a second calibration point of the at least three calibration points is at a second temperature and second pressure; and a third calibration point of the at least three calibration points is at the first or second temperature and at a third pressure which is different from the first or second pressure.