Experimental validation of the frequency tuneability of a photonic microwave filter using a bireffingent optical fibre-based interferometer

An experimental demonstration of a nonperiodic transversal-like tuneable photonic microwave filter is reported. The finite impulse response (FIR) is directly synthesised in the optical domain by slicing an optical broadband source with an interferometric scheme, based on a birefringent fibre. The analysis of the temperature behaviour of this fibre permits an adjustment of the central frequency of the microwave filter. Experimental results validate the potential tuneability property of such filters.