Microwave photonic filter with two independently tunable passbands based on paralleled fiber Mach–Zehnder interferometers and dispersive medium

Abstract

In this article, we propose and experimentally demonstrate a novel microwave photonics filter (MPF) with two independently tunable passbands. The MPF is based on a sliced broadband optical source and a dispersive medium, and two paralleled fiber Mach–Zehnder interferometers (FMZIs) have been employed as the optical spectrum slicer. A coil of single-mode fiber has been used as a dispersion medium, which introduces time delay for each tap. A stable dual-passband MPF has been obtained, and the experimental results show that each passband of the MPF can be tuned freewill by adjusting the variable optical delay line (VODL) in each of the FMZIs.