Research On Generation Of Optical Millimeter Wave Based On DPMZM And PolM

Compared with traditional wireless communication,Radio-over-Fiber(Ro F)technology combines optical communication with large bandwidth,low loss and wireless communication anytime,anywhere access to the characteristics of services,representing the future development trend of optical communication networks and wireless communication network and making it a hot spot for future communication research.One of the key technologies in the Ro F system is how to avoid the difficulties of creating high-frequency millimeter-wave or high costs in traditional electric fields,and switch to increasingly sophisticated optical technology to produce high-frequency,low-noise millimeter waves.At present,60 GHz millimeter wave communication due to the frequency of free,high transmission rate advantage has been a great concern.This paper focuses on the use of an external modulator to study the optical generation and transmission performance of 60 GHz millimeter waves.Work priorities and innovations are as follows:1.The paper introduces the principle and characteristics of Ro F technology,optical millimeter-wave technology,optical external modulator,MZM modulator based on the three traditional modulation technology and the new modulation sideband method,two typical dispersion effect in Ro F system and other basic theoretical knowledge,and respectively the theory and simulation research on the generation and transmission of optical millimeter wave.2.In this paper,Because of the influence of the periodic fading effect and symbol constrained effect on the transmission distance and capacity of the RF signal power in the three traditional modulation technologies of the Ro F system,The dual-parallel MZM(DPMZM)for quadruple frequency optical millimeter wave is proposed.The novelity of optical millimeter wave program is that by controlling the two sub-MZM modulation indexes of DPMZM,it outputs the negative first order optical sideband and the positive third order optical sideband,and then to obtain the millimeter wave signal by photoelectric conversion.Since the baseband signal in the Ro F link is only loaded on the negative first order optical sideband,the baseband signal symbol constrains can be avoided,and the RoF system is more stable and simpler because no optical filter is needed.In this paper,the 2.5Gbit / s baseband signal is modulated to the negative first order edge band,and the transmission performance of the Ro F system is simulated by maintaining the pure third order optical sideband.The simulation results show that the quality of the eye is still clear after 75 km transmission distance,but the bit error rate is drastically deteriorated after 20 km transmission of the traditional quadruple frequency scheme.3.Two cascaded polarization modulators(Pol Ms)to produce low spectral purity and tunable multiplication factor microwave signal generation method is proposed and demonstrated by simulation.By appropriately adjusting the direction of the polarizer and the power and phase of the RF drive signal,Frequency quadrupling,sextupling,or octupling can be obtained without an optical filter.The feasibility of the above millimeter wave generation scheme is verified by formula derivation and simulation.Finally,the transmission performance of the octupling frequency of the cascade polarization modulator with 2.5 Gbit / s baseband signal is analyzed.