Synthesis of photonic microwave filters based on external optical modulators and wide-band chirped fiber gratings

The synthesis of photonic microwave filters employing optical sources with modulation side-bands, as multimode optical sources, and chirped fiber gratings is addressed. A single wavelength laser externally modulated using electrooptical Mach-Zehnder modulators and electroabsorption modulators have been proved as optical sources with modulation sidebands. Microwave filter features such as wide range tunability, compactness, readily reconfigurable frequency responses and flexibility have been achieved and demonstrated for the proposed structure. Experimental results using both a dual-electrode Mach-Zehnder electrooptical modulator and an electroabsorption modulator as optical sources with modulation sidebands are provided to demonstrate the feasibility of this technique.