Wideband RF photonic pre-selector for dynamic co-site interference mitigation

Abstract

The use of optical interferometry within an optical waveguide structure for null frequencies is well understood. We demonstrate a useful application of a related technique using unbalanced outputs of a dual output Mach-Zehnder modulator combined with a balanced detector to provide frequency agile, dynamic co-site interference mitigation. We will show the extreme wideband performance of this all optical solution by rejecting interferer frequencies by over 40 dB. We initially apply this technique to the challenging sub-octave microwave communications environment and suggest that the utility of this technique actually improves up into the millimeter bands.