Title :
Extrinsic Fabry-Perot interferometer fiber-optic microphone
Author :
Fürstenau, Norbert ; Horack, H. ; Schmidt, Walter
Author_Institution :
Inst. of Flight Guidance, German Aerosp. Center, Braunschweig, Germany
fDate :
2/1/1998 12:00:00 AM
Abstract :
In this paper we describe a new fiber-optic microphone developed as a passive acoustic sensor for traffic monitoring and vehicle classification. It is based on a fiber-optic extrinsic Fabry-Perot (FP) microinterferometer coupled to an external membrane for modulating the FP cavity length and a low coherent superluminescent diode as light source. The frequency characteristic as compared with a standard condenser microphone exhibits a sensitivity range of more than 80 dB between 100 Hz and 15 kHz. Initial results are presented demonstrating acoustic monitoring of aircraft via their characteristic noise spectra using downleads of km length
Keywords :
Fabry-Perot interferometers; acoustic transducers; airports; fibre optic sensors; ground support equipment; microphones; nonelectric sensing devices; pattern classification; spectral analysis; traffic control; 100 Hz to 15 kHz; FP cavity length; acoustic monitoring; aircraft; characteristic noise spectra; coherent superluminescent diode; external membrane; extrinsic Fabry-Perot interferometer; fibre optic microinterferometer; fibre optic microphone; frequency characteristics; light source; passive acoustic sensor; standard condenser microphone; traffic monitoring; vehicle classification; Acoustic sensors; Biomembranes; Fabry-Perot interferometers; Microphones; Monitoring; Optical coupling; Optical fiber sensors; Optical modulation; Superluminescent diodes; Vehicles;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
