RF photonic techniques can be used to extend operating frequencies and bandwidth of mission communications and sensing systems. Photonic links inherently cover wide frequency bandwidths and optical modulators and detectors have been demonstrated that operate up to 100 GHz. This paper presents a photonic method for tunable high frequency carrier generation and wideband tunable RF frequency conversion. Photonic down-conversion measurements are presented with +24 dBm OIP3 and positive gain across RF input signals from 5 to 20 GHz. Additionally, measurements of undesired higher order mixing spurious products were more than 30 dB lower than those of typical RF mixers. Coupling wide-band optical components with a reconfigurable RF payload provides unprecedented agility and multi-mission utility for remote sensing, communications and SAR radar missions.