Optical Fiber Sensors

12Distributed Fiber-Optic Sensors and Their Applications

Balaji Srinivasan and Deepa Venkitesh

Contents

12.1 Introduction

12.2 Background

12.2.1 Fundamentals of Light Scattering in Optical Fibers

12.2.2 Basics of OTDR

12.2.2.1 Design of the OTDR Receiver

12.2.2.2 Noise Sources in the OTDR Receiver

12.2.2.3 Design of the PIN-Based Receiver

12.2.2.4 Design of the APD-Based Receiver

12.2.2.5 SNR Improvement through Averaging

12.2.2.6 SNR Improvement through Savitzky–Golay Filtering

12.2.2.7 SNR Improvement through Correlation Coding

12.2.3 Physical Parameter Sensing Using OTDR

12.3 Distributed Temperature Sensing Using Raman Scattering

12.3.1 Typical Configurations

12.3.2 Simulation Results and Design

12.3.2.1 Model for Distributed Temperature ...