Research On Dispersion Suppression In Microwave Photonic Frequency Conversion Link

Microwave photonic frequency conversion technology is an important research content in microwave photonics.It has the advantages on wide bandwidth,low loss and strong ability to resist electromagnetic interference and improve the performance of the frequency conversion system.This paper studies the microwave photonic frequency conversion link and the dispersion suppression method based on it.In this paper,firstly,the development background,the research content and the research status of microwave photonics and microwave photonic frequency conversion technology are introduced.The significance of the research on microwave photonic frequency conversion technology is clarified,which also point out that the research scheme in this paper conforms to the trend of diversification of microwave photonic frequency conversion links.Secondly,the essential devices of the microwave photonic links,including light source,modulator,optical fiber and so on are introduced,as the theoretical basis for the microwave photonic frequency conversion link.Thirdly,the parameters of microwave photon frequency conversion link are introduced,and the specific frequency conversion scheme is explained and analyzed further.Finally,the theory and simulation of microwave photon frequency conversion method based on cascaded Mach-Zehnder modulator(MZM)are analyzed.The scheme proposed in this paper is as follows:(1)A dispersion suppression method for microwave photonic links based on Polarization Division Multiplexing Dual-Parallel Mach–Zehnder Modulator(PDM-DPMZM)is proposed.Through theoretical analysis and mathematical deduction,the DC voltage setting condition of the modulator is obtained,which can suppress the dispersion in the proposed link.When the length of the fiber or the frequency band of the input signal are changed,the method can suppress dispersion of the links without adjustment of the modulator parameters.(2)Based on the dispersion suppression scheme proposed in this paper,a method of microwave photonic dispersion suppression frequency conversion based on Polarization Division Multiplexing Dual-Parallel Mach–Zehnder Modulator is proposed subsequently.Through theoretical analysis and mathematical deduction,the setting conditions of DC voltage of the modulator are obtained,which completes the microwave photon up-conversion and suppresses the dispersion of optical fiber.By balanced detection method,the gain of the link is improved.The method has excellent dispersion suppression performance on the scenarios with different fiber lengths and input signal frequency bands,which proofs that the method is applicable to long-distance fiber transmission system applications.Due to the proposed method using the Polarization Division Multiplexing Dual-Parallel Mach–Zehnder Modulator,a kind of the highly-integrated microwave photonic devices,the link structure is simplified and the system stability is improved.In summary,the proposed scheme of microwave photon frequency conversion to suppress link dispersion in this paper successfully suppresses the influence of dispersion and completes the frequency conversion.The dispersion suppression operation is simple and stable.It is of theoretical and practical significance in the application of microwave photon frequency conversion technology.