Broad-band millimeter-wave upconversion by nonlinear photodetection using a waveguide p-i-n photodiode

We propose and demonstrate the nonlinear photodetection technique for broad-band fiber-optic millimeter-wave distribution systems. An unmodulated millimeter-wave carrier and intermediate frequency (IF) signals on separate optical carriers are delivered to a single photodetector, where they are O/E converted and mixed simultaneously to generate radio frequency (RF) signals. It is demonstrated that a mixing bandwidth broader than 2 GHz and a spurious-free dynamic range higher than 90-dB/spl middot/Hz/sup 2/3/ are achieved for millimeter-wave frequency at 66 GHz. In the experiment, the nonlinear photodetection is realized by using a commercially available waveguide p-i-n photodiode under its saturation condition.