Simultaneous Generation and Transmission of Downstream Multiband Signals and Upstream Data in a Bidirectional Radio-Over-Fiber System

We propose and experimentally demonstrate simultaneous generation and transmission of downstream multiband signals and upstream data in a bidirectional radio-over-fiber system. The scheme is based on a dual-parallel Mach-Zehnder modulator and a following single-drive Mach-Zehnder modulator. Multiband data including baseband, frequency-doubled, and frequency-quadrupled signals are generated through optical carrier suppression and frequency-shifting techniques. Upstream data transmission is realized by remodulation of the downstream differential phase-shift-keying signal without the need of additional light source and wavelength management at the base station.