Patent ID: 8329107

Claim:
A sensor that generates an output signal in response to a stimulus, wherein the output signal is generated with a predetermined relationship to one or more properties of the stimulus such that the one or more properties of the stimulus can be determined as a function of the output signal, the sensor comprising: a component that deteriorates, wherein the deterioration of the component causes predictable fluctuations in the predetermined relationship between the output signal and the one or more properties of the stimulus; a sensor processor that provides information related to the deterioration of the component; and a transmitter that wirelessly transmits the information provided by the processor, wherein the component deteriorates at a rate that is substantially proportional to an amount of time, and wherein the sensor processor provides information related to the amount of time, and wherein the amount of time includes a total amount of time that has elapsed since the sensor was last calibrated, and wherein calibrating the sensor includes determining the predetermined relationship between the output signal and the one or more properties of the stimulus that enables the one or more properties of the stimulus to be determined as a function of the output signal.