A Novel Bidirectional 60-GHz Radio-Over-Fiber Scheme With Multiband Signal Generation Using a Single Intensity Modulator

We experimentally demonstrated a novel radio-over-fiber system to simultaneously generate dispersion-tolerant multiband downstream signals, including millimeter-wave, microwave, and baseband signals, based on multicarrier modulation in an intensity modulator and a subsequent optical filter. The uplink connection is realized by remodulation of downlink optical carrier and by baseband detection in the central office. The high-dispersion tolerance comes from the subcarrier cross-selection with only one data-bearing tone before signal beating in the receiver. The power penalty of 1.4 dB for 60-GHz carrier and negligible degradation for baseband and upstream are achieved for 2.5-Gb/s signal after 50-km single-mode fiber (SMF-28) and 4-m air link transmission. The theoretical analysis is also provided to obtain the optimal operation point.