Suppression of cable induced noise in an interferometric sensor system

Abstract

Vibrations in the lead cables is known to cause noise in interferometric sensor systems, through modulation of the polarization state of the transmitted light, and through Doppler stretching of the interrogating signals. We demonstrate effective methods for suppression of both these noise sources. The polarization modulation sensitivity is suppressed by 36 dB by using a polarization resolved interrogation technique. The sensitivity to Doppler shift is suppressed by 22 dB by using a reference interferometer that is interrogated through the same lead fiber.