Fiber Optic Vector Sensor Sonobuoy System

VIP Sensors proposes to develop a very low noise, highly sensitive Fiber Optic Vector Sensor (FOVS) System packaged in a size - A sonobuoy. The FOVS includes a triaxial optical accelerometer, an omnidirectional optical hydrophone and an optical compass. Only a pair of single mode optic fibers interconnects the fully passive vector sensor located below sea level to the sonobuoy"s Surface Electronic System. The FOVS measures the amplitude and direction of sound wave and provides its spatial orientation regarding the magnetic north and its pitch relative to the horizon. All the sensors are Extrinsic Fabry-Perot Fiber Optic MEMS devices built with spectrally selective micro-mirrors designed to be sensitive only to one particular measurand: acceleration or pressure or to the earth magnetic field. Each the sensors operate at a unique optical wavelength range within the C and L telecommunication bands. The FOVS is configured as two sensor segments in parallel, separated by an optical time delay, one segment has three accelerometers and a hydrophone, the other has three magnetic sensors that make up the compass. The Interrogation Module separates the signal spectrum of the sensors in a given segment, in a Wave Division Multiplexing fashion; and time multiplexes the sensor segments.