Patent ID: 7999930
Filing Date: 2011-08-16
Classification: C03B,G01L,G01M,G02B

Abstract:
1. A detection system comprising: (i) an optical fiber, said optical fiber having (a) a length L≧1 km; (b) effective beat length between 10 m and 200 m; and (c) beat length uniformity over the length of the fiber is characterized by standard deviation σ, where |σ|≦10 m; (ii) an OTDR coupled to said fiber and including (a) a radiation source providing pulsed radiation to said fiber, (b) a detection system capable of detecting radiation that is backscattered back by the fiber; (iii) at least one polarizer situated between said fiber and said detector, such that the backscattered radiation passes through said polarizer before reaching said detector.