Compact Tunable Microwave Filter Using Retroreflective Acousto-Optic Filtering And Delay Controls

Programmable broadband rf filters are demonstrated using a compact retroreflective optical design with an acousto-optic tunable filter and a chirped fiber Bragg grating. This design enables fast 34 μs domain analog-mode control of rf filter time delays and weights. Two proof-of- concept filters are demonstrated including a two-tap notch filter with \u3e35 dB notch depth and a four-tap bandpass filter. Both filters have 2-8 GHz tunability and a 34 μs reset time. © 2007 Optical Society of America