Advanced design of a complex fiber Bragg grating for a multichannel asymmetrical triangular filter

Abstract

Employing discrete layer peeling incorporated with a traditional Gerchberg-Saxton algorithm, we demonstrate an advanced design for a complex fiber Bragg grating (FBG) with a multichannel asymmetrical triangular reflection spectrum. This type of FBG filter is designed for multiplexing wavelength interrogation in a fiber-optic measurement system. The proposed method creates a FBG with a smooth index-change profile, and should facilitate its fabrication. Moreover, under the condition of quadratic phase response of the FBG, the dependences of the reconstructed index-change profile on the phase responses of the triangular filter are numerically investigated.