Title :
Tunable Photonic Microwave Filter Using a Superstructured FBG With Two Reflection Bands Having Complementary Chirps
Author :
Blais, Sebastien R. ; Yao, Jianping
Author_Institution :
Univ. of Ottawa, Ottawa
Abstract :
A tunable photonic microwave bandpass filter using a superstructured fiber Bragg grating (SFBG) with two reflection bands having complementary chirps is proposed. Being different from a regular chirped FBG, which is usually fabricated using a chirped phase mask with a fixed chirp rate, the SFBG with complementary chirps is fabricated using a uniform phase mask and a chirped sampling function. The chirp rate of the sampling function can be designed to realize specific equivalent chirp rates that are complementary in the 1st-order and the 1st-order reflection bands of the SFBG. An SFBG with complementary chirps is fabricated and characterized. The use of the SFBG to implement a photonic tunable microwave filter with a negative coefficient is experimentally demonstrated.
Keywords :
Bragg gratings; band-pass filters; microwave filters; microwave photonics; optical fibre filters; bandpass filter; chirped phase mask; complementary chirps; reflection bands; superstructured FBG; superstructured fiber Bragg grating; tunable photonic microwave filter; uniform phase mask; Band pass filters; Bragg gratings; Chirp; Fiber gratings; Low pass filters; Microwave filters; Optical fiber filters; Optical filters; Optical reflection; Sampling methods; Equivalent chirp; photonic microwave filter; superstructured fiber Bragg grating (SFBG); tunable microwave filter;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2007.912493
