DOWNHOLE QUARTZ GAUGE WITH MINIMAL ELECTRONICS

摘要

A system and method of monitoring a pressure, temperature, and/or vibration of a hostile environment without requiring the use of active electronics or an oscillator circuit. The system and method interrogate a resonant pressure sensor and a resonant or passive temperature sensor connected to a transmission line and located at least 100 feet away from a network analyzer. The system and method use thereflected frequencies from the sensors to determine the pressure, temperature, and/or vibration. If the sensors are networked by the transmission line or a network filter, the reflected portion can include the reflected transmission energy. The applied signal and reflected portion travel along the transmission line, which Is preferably impedance matched to that of the system. If. a multi -conductor cable is used, the effects of the cable's length and temperature are compensated for via a system calibration when in field use.