Research on the weak signal detection technique based on optical fiber Mach-Zehnder interferometer

An analysis, based on transfer matrix, is presented of weak signal effects on the mach-zehnder interferometer sensor for detection. The weak signal detector based on Mach-Zehnder optical fiber interferometer is established. Based on wavelet soft-threshold de-noising technology and high-pass filter, a modified demodulation technique is proposed. With the modified demodulation method, experiment results show the system's precision can be improved effectively.