a pressure measurement system and method are described . the system uses a tunable laser and a fabry - perot sensor with integrated transducer . a detector senses the light modulated by the fabry - perot sensor . a signal conditioner , which can be located up to 15 km away , then uses the detector signal to determine the displacement of the diaphragm , which is indicative of pressure exerted against the diaphragm . use of a temperature sensor to generate a signal , fed to the signal conditioner , to compensate for temperature is also contemplated .