Analytical models for predicting required response of mandrel-type fiber optic acoustic sensors for ocean and seismic applications

Abstract

Fiber optic acoustic sensor systems have been developed by industry, university, and government research teams which meet enhanced requirements for arrays with high sensor counts, high dynamic range, wide bandwidths, and will operate reliably for a decade or more in high-pressure-high-temperature pipeline, ocean, and seismic environments. Optical sensors do not require vulnerable electrical telemetry in the “wet” end of the system, and can reliably transmit high sensor count string outputs which are 10's of km from the light source and acoustic data processors. This paper introduces a modified version of the SONAR equation which allows a straight forward estimation of the required fiber optic acoustic sensor array response to capture the desired acoustic signal detail necessary to interpret the target or seismic event. This enables system design engineers to define and optimize sensor response requirements early on, and help minimize prototype and production system performance and budget risks.