The Techonology Of Arbitiary Frequency Multiplication Based On Microwave Photonics

The emergence and development of microwave photonic technology has effectively solved many problems faced by traditional electronic methods and has a lot advantages,such as anti-electromagnetic interference,lower transmssion loss and higher frequency spectrum utilization.It also provides a new technical solution for microwave signal generation,transmission,control and processing.In the existing microwave photonic scheme,the frequency doubling factor is single and does not have continuously adjustable characteristics,this thesis mainly researches on the arbitrary frequency multiplication technology based on microwave photonics,put forward some new structure microwave photonic scheme,after detailed mathematical deduction,simulation analysis and experimental verification,the sysyem has a high stability,good ability of tuning the microwave signal.The main contents of the thesis are as follows:1.Firstly,the physical structure and basic working principle of the Mach-Zehnder modulator and the Dual-parallel Mach-zehnder modulator are introduced systematically,the theoretical analysis of the multiple frequency modulation scheme based on DPMZM structure is carried out systematically,and the parameter conditions of realizing the microwave signal with different frequency doubling factor(FMF)are given.Through the simulation and experimental analysis,microwave signals with frequency of 40GHz,60GHz and 80GHz are verified by using a local oscillator signal of 10GHz,and the corresponding RFSSR is 40.64dB,24.88dB and 25.83dB.2.Considering the limitations of DPMZM structure multiple frequency doubling system,the microwave signal generation scheme based on the cascade structure of PM and DPMZM is innovatively proposed.Theoretical derivation and simulation analysis of the scheme were carried out,and experimental links were established to verify the tunable accuracy of the frequency multiplier factor,which can generate microwave signals with frequency multiplication factors of 2,3 and 4.Ultimately,the system input RF local oscillator signal of 10GHz can generate pure signals of 20GHz,30GHz and 40GHz,the corresponding RFSSR were 22.32dB,20.08dB and 10.47dB.3.This theis innovatively proposes a new microwave photon multifrequency multiplication scheme based on the multi-DPMZM structure whose frequency multiplication factor is continuously adjustable from 3 to 10,which can achieve the microwave with 3,4...,10 times the frequency of the local oscillator signal.The corresponding RFSSR is all higher than 20dB,the highest can reach 36dB.The accuracy of the system in the continuously tunable frequency multiplication factor is verified by simulation experiments,and the influence of the modulator extinction ratio on the RFSSR of the microwave signal is analyzed.Compared with the traditional microwave photon frequency doubling technology scheme,the system has good frequency tunability,the frequency doubling factor FMF can reach up to 10,and at the same time,it realizes the rare frequency doubling of odd numbers such as 3,5,and 7,and has better performance.The stability can well meet the flexible frequency requirements in future communications.