Efficient Photonic Generation of Millimeter-Waves Using Optical Frequency Multiplication in Radio-over-fiber Systems

Photonic millimeter-wave (mm-wave) generation using optical frequency multiplication (OFM) is considered as a cost-effective solution in radio over fiber (RoF) systems. We comprehensively investigate the generation of mm-waves using high-order harmonic generation with a dual-electrode Mach-Zehnder modulator (DE-MZM) theoretically and experimentally, considering; the DE-MZM bias condition and finite extinction ratio. We consider three bias cases, i.e. maximum transmission bias (MATB), minimum transmission bias (MITB) and quadrature bias (QB). Our analysis shows that MATB is the best for the generation of mm-waves using the fourth order harmonics, and the generated mm-waves are almost immune to fiber dispersion. On the contrary, MITB is the best for the generation of mm-waves using the second or sixth-order harmonics, and the mm-waves generated are almost immune to fiber dispersion, too. Mm-waves generated with the QB always suffer from the impact of fiber dispersion.