Noise cancellation in distributed feedback laser based interrogation system for twin grating accelerometer

In this paper, we demonstrate a noise cancellation method for suppressing laser frequency noise in distributed feedback laser based system for interrogating a twin fiber Bragg grating based accelerometer. A simple method has been developed by studying the noise characteristics of the sensing photodiode and the reference photodiode, used in standard intensity based wavelength demodulation system. Proposed method could be able to reduce deterministic noise components to about 20% of the original noise components without using any complex feedback mechanism to stabilize the laser.