Programmable Photonic Microwave Filters With Arbitrary Ultra-Wideband Phase Response

We present a coherent optical signal-processing approach for synthesis of programmable microwave phase filters over an ultra-wideband. Our scheme relies on a programmable optical phase filter implemented in a pulse-shaping geometry incorporating a spatial light modulator and hyperfine (~600-MHz spectral resolution) optical spectral disperser. The user-defined optical phase filter is directly transferred to the electrical domain through heterodyne conversion, and the overall system response is characterized via vector network analyzer measurements. We illustrate our approach by synthesizing linear, quadratic, and cubic spectral phase functions over a 20-GHz band. To our best knowledge, this is the first realization of programmable arbitrary microwave phase filters over such a bandwidth