Optical millimeter-wave generation with tunable multiplication factors and reduced power fluctuation by using cascaded modulators

In this study, we propose and demonstrate a prototype for optically generating millimeter-wave (MMW) signals with tunable multiplication factors and reduced power fluctuation. The proposed scheme is based on two Mach-Zehnder modulators (MZM) and a polarization control system. By controlling the polarization direction, the amplitudes of first and third order optical sidebands can be flexibly controlled. The optical sideband suppression ratio (OSSR) between them can be tuned within the range of 50 dB to −50 dB, which provides an opportunity to convert the multiplication factor between 2 and 6. Benefited from the high OSSR, the generated MMW signals show anti-power fluctuation capability either in the transmission process or in the frequency-tuning process. The relations of received signal power, transmission distance, bit error rate (BER), receiver sensitivity, power penalty and a contrast experiment are discussed in this paper.