Patent ID: 7235987

Claim:
A sensor device comprising: a sensor in which a resistance value is changed in accordance with a change in an environment of the sensor; and a beat oscillator having plural oscillators of different oscillating frequencies and generating a beat signal of a frequency lower than the oscillating frequencies, wherein the beat signal corresponds to a difference of the oscillating frequencies, and wherein the beat oscillator is electrically connected to the sensor such that the frequency of the beat signal changes in accordance with the change in the resistance value of the sensor; wherein the resistance value is changed in accordance with a pressure change in the environment, wherein the sensor has a first and second sensor, wherein the resistance values of the first and second sensors change inversely in relation to each other due to the pressure change of the environment; wherein the beat oscillator has a first beat oscillator electrically connected to the first sensor, wherein the frequency of the beat signal of the first beat oscillator changes in accordance with the resistance value of the first sensor; wherein the beat oscillator has a sensor beat oscillator electrically connected to the second sensor, wherein the frequency of the beat signal of the second beat oscillator changes in accordance with the resistance value of the second sensor; and further comprising a temperature compensating section for: calculating at least one of: the beat signals of the first and second beat oscillators; and a difference of a first and second frequency dividing signal provided by dividing the frequencies of the beat signals of the first and second beat oscillators; and compensating for detecting pressure with respect to temperature.