Large-Scale Interferometric Fiber Sensor Arrays Incorporating Multiple Optical Switches

✍ Scribed by C.W. Hodgson; M.J.F. Digonnet; H.J. Shaw

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 131 KB
• Volume: 4
• Category: Article
• ISSN: 1068-5200
• DOI: 10.1006/ofte.1998.0257

✦ Synopsis

We have developed a novel fiber sensor array telemetry that uses multiple all-fiber, all-optical switches for time domain multiplexing. Incorporating optical switches improves the telemetry by connecting only one sensor at a time to the buses and thus delivering the largest possible signal power to each sensor and to the receiver. We report the first laboratory demonstration of such an array using optical Kerr effect switches and discuss the requirements of the switches needed for a practical array. ᮊ 1998 Academic

Press

I. INTRODUCTION

Many types of fiber sensors, including hydrophones, have been highly researched w x and engineered 1, 2 , yet widespread commercial applications are still lagging. The primary reason is that although fiber sensors are inherently inexpensive, the cost of sensor systems is prohibitive because of the large number of optical sources and receivers they require. Sources and receivers tend to be expensive and consume a large amount of space and power. If the cost of fiber sensor systems can be reduced, they will become competitive in the sizable market for large-scale towed hydrophone arrays. These arrays are important for seismic exploration and mapping of energy resource fields. This market is currently dominated by piezoelectric sensors, which are much less sensitive than fiber sensors, very bulky, and heavy. Thus they require large ships to be towed through the water, and they are difficult and expensive to maintain. Because of the difficulty in maintaining electrical arrays in practice and because of the great potential that fiber optics holds in this field, all-fiber hydrophone sensor arrays usually do not involve electrical connections to the array.