Patent ID: 7373272
Filing Date: 2008-05-13
Classification: G01B,G01D,G01K

Abstract:
1. A position sensing system, comprising: a variable frequency signal source coupled to receive a frequency control signal and operable, in response thereto, to supply a radio frequency sensor drive signal at a frequency; a transmission line sensor having one or more resonant frequencies, the transmission line sensor including a sensor conductor and a moveable dielectric at least partially surrounding the sensor conductor, the sensor conductor having a driven end coupled to receive the sensor drive signal and a terminal end configured to reflect the sensor drive signal to thereby supply a reflected signal to the driven end, the moveable dielectric configured to receive a drive force and, upon receipt thereof, to move the dielectric to a position and thereby vary the one or more resonant frequencies of the transmission sensor; and a summing and temperature sense circuit including one or more circuit elements having an electrical characteristic that varies with temperature, the summing and temperature sense circuit coupled to receive the radio frequency sensor drive signal and the reflected signal and operable, in response thereto, to supply a standing wave signal having an amplitude that varies with the one or more resonant frequencies of the transmission line sensor, the summing and temperature sense circuit further coupled to receive a direct current sensor excitation signal and operable, in response thereto, to supply a temperature signal representative of transmission line senor temperature.