Generation of Multiband Signals in a Bidirectional Wireless Over Fiber System With High Scalability Using Heterodyne Mixing Technique

We propose and experimentally demonstrate a bidirectional radio over fiber system to simultaneously generate and transmit downstream multiband signals and upstream data. To the best of our knowledge, this is the first time that the multiband signals, including baseband, 24-GHz microwave (MW), and 42- and 60-GHz millimeter-wave (MMW) signals, are realized through multicarrier generation and heterodyne mixing techniques. The frequencies of the MW and MMW signals are continuously tunable, thus high scalability can be achieved. In the base station, part of the continuous wave light is used as an optical carrier for upstream data, which is transmitted back to the central station though the same fiber. Error-free performances are achieved for all the signals after 25-km single-mode fiber and 5 ft air link transmission for wireless data.