Title :
Comparison of fiber-optic Sagnac and Mach-Zehnder interferometers with respect to thermal processes in the fiber
Author :
Kråkenes, Kjell ; Bløtekjær, Kjell
Author_Institution :
Simrad Optronics A/S, Oslo, Norway
fDate :
4/1/1995 12:00:00 AM
Abstract :
The impact of thermal noise in the fiber on the noise power and signal-to-noise ratio (SNR) of fiber-optic sensors is investigated, and sensors based on the Sagnac and the Mach-Zehnder interferometers are compared. The SNR is almost the same for the two interferometers; the Mach-Zehnder interferometer has slightly higher SNR at low frequencies, whereas the Sagnac interferometer may have a few dB higher SNR at high frequencies. It is also shown that thermal noise may dominate over shot noise for realistic system parameters, in which case a Sagnac interferometer has several advantages over a Mach-Zehnder interferometer
Keywords :
Mach-Zehnder interferometers; fibre optic sensors; light interferometers; optical fibres; optical noise; shot noise; thermal noise; SNR; fiber-optic Mach-Zehnder interferometers; fiber-optic Sagnac interferometers; fiber-optic sensors; high frequencies; low frequencies; noise power; realistic system parameters; shot noise; signal-to-noise ratio; thermal noise; thermal processes; Frequency; Low-frequency noise; Optical fiber sensors; Optical fibers; Optical interferometry; Optical noise; Phase modulation; Sagnac interferometers; Signal to noise ratio; Thermal sensors;
Journal_Title :
Lightwave Technology, Journal of
