Real Time Measuring System of Multiple Chemical Parameters Using Microstructured Optical Fibers Based Sensors

In this paper, a multiplexing system for simultaneous interrogation of optical fiber sensors which measure different parameters is presented and validated. The whole system has been tested with six different sensing heads with different purposes: one temperature sensing head, two relative humidity sensors, and three VOCs leak sensors; all of them based on microstructured optical fibers. The interrogation system uses the fast Fourier transform technique to isolate each sensor's interference, enabling their simultaneous interrogation. The system interrogates all the sensors at frequencies up to 1 KHz, showing a good performance of each measurement without crosstalk between sensors. The developed system is independent of the sensors' purpose or of the multiplexing topology.