Application Research Of Pulse Position Modulation In High Speed Optical Label Switching System

In modern society,science and technology are developing rapidly.with the development of big data,artificial intelligence,cloud computing,5G communication and other emerging industries and technological innovation,the demand for information transmission rate and data transmission capacity is getting higher and higher,and the innovation of optical communication technology is becoming more and more urgent.At present,the optical transmission network has reached 100 G commercialization,and the research of 400 G module is being carried out.The photoelectric switching problem caused by high speed is becoming more and more prominent.Solving the problem of photoelectric switching and improving the overall data transmission rate is the development requirement of modern information society.Based on this background,Pulse Position Modulation(PPM)and Quadrature Amplitude Modulation(QAM)are introduced into the optical label switching system.The basic theory and technical principle of Pulse Position Modulation(PPM)and its transmission characteristics in high-speed optical label switching system are analyzed.A high-speed 16QAM/PPM optical label switching system model is built using simulation software VPI.This paper mainly studies the following contents:Through literature reading,the paper introduces the development status of optical fiber communication technology and optical switching technology,and analyzes the specific implementation schemes and key technologies of optical label switching technology.The pulse position modulation technology and the quadrature amplitude modulation technology are analyzed.The basic principles,basic frame structure and technical scheme types are introduced.The basic signal modulation principle and the signal realization and demodulation methods of the quadrature amplitude modulation technology are introduced.Based on the above principles,the simulation of the optical label switching system with a payload rate of 40 Gb/s is carried out.With 16 QAM as the payload signal modulation mode and 2PPM as the label signal modulation mode,the parameters of the key components in the system are optimized and the transmission characteristics of the system are analyzed.The results show that the 40 Gb/s 16QAM/2PPM optical label switching system has good system performance and transmission characteristics.The generation mode of PPM signal is optimized and analyzed.It is concluded that 64 PPM has better transmission characteristics in local range.According to the above simulation system,the modulation rate of 16 QAM is increased to 160Gb/s and 640Gb/s,and the optical label switching system is built with 64 PPM label.The parameters of key components in the simulation system are optimized and analyzed,including the bandwidth of optical bandpass filter,bandwidth of electrically low pass filter and frequency interval between label charges,and analyzed the optimized system transmission performance.The results show that for the high-speed 16QAM/64 PPM optical label switching system,both label and payload have good reception effect,and the power cost of label and payload does not exceed 3dB after 96 km transmission in the optical fiber.The overall optical label switching system shows good transmission characteristics.