Patent ID: 7808623
Filing Date: 2010-10-05
Classification: G01B,G01M

Abstract:
1. A method comprising: generating a first optical signal at a first end of an optical fiber segment at a first time; detecting the first optical signal at a second end of the optical fiber segment at a second time; generating a second optical signal at a second end of the optical fiber segment at a third time in response to the detection of the first optical signal; detecting the second optical signal at the first end of the optical fiber segment at a fourth time; generating a third optical signal at the first end of the optical fiber segment at a fifth time in response to the detection of the second optical signal; detecting the first optical signal at a location along the optical fiber segment between the first end and the second end at a sixth time; detecting the second optical signal at the location along the optical fiber segment between the first end and the second end at a seventh time; detecting the third optical signal at the location along the optical fiber segment between the first end and the second end at an eighth time; and determining a length of the optical fiber segment based on a difference between the third time and the second time, a difference between the fifth time and the fourth time, a difference between the seventh time and the sixth time, and a difference between the eighth time and the seventh time.