A tunable dual-passband microwave photonic filter based on optical slicing and dual-path fiber delay lines

In this article, a dual-passband microwave photonics filter (MPF) based on spectrally sliced broadband optical source (BOS) and a dual-path fiber delay line has been proposed and experimentally demonstrated. Continuous optical samples are obtained when a BOS is sliced by a fiber Mach-Zehnder interferometer (FMZI). Dual-passband frequency response has been realized by utilizing two dispersive fiber delay lines with different length and recombining two groups of delayed samples on the photodiode (PD). The proposed dual-passband MPF is stable and the central frequencies of the passbands can be tuned continuously by either changing the free spectral range of the FMZI or the length of dispersive fiber delay lines. Furthermore, multi-passband MPF with desirable passband central frequencies can be achieved by using the proposed technique, which shows good application potentials in the wireless communication and measurement systems. (C) 2015 Elsevier B.V. All rights reserved.