Study Of The Effect On The Pulse Due To Polarization Mode Dispersion In The Optical Fiber Communication System

Polarization Mode Dispersion (PMD) causes pulse broadening because of the difference in speed between two polarized modes in optical fiber communication systems. It limits the upgrading of bit rates and span of relay distance. Solving PMD is the key to realizing optical long-haul transmissions systems and becomes one of the most important considerations. The difficulty of solving PMD lies in its randomness of differential group delay (DGD) betweenthe principal states of polarization (PSP) and the change in PSP with time and wavelength. So Polarization Mode Dispersion is becoming more important and is paid more attention now. The impact of PMD on high-speed data transmission and the key technologies of PMD compensation are the focus of optical fiber communication system in the word. The basic research task about PMD includes the fundamental theory, the PMD emulator and the techniques of measurement and compensation. Therefore, study of PMD due to pulse broadening is important to improvement of optical fiber communication system. The importance of PMD and the foreign and domestic status of studying PMD are expounded. And Polarization Mode Dispersion and its Influence on the Propagation of Light Pulse are expounded is this article. The details show as following:Several popular methods of the PMD measurement and compensation are also expounded here. The pulse root mean square (RMS) broadening is a main physical variable to judge signal transmission performance. We derive the broadening effects induced by the PMD, and give the exact analytical expressions for the expected pulse broadening in a fiber-optic transmission system suffering from first-order polarization mode dispersion (PMD). And the light pulses which are propagating with PMD are also simulated. Then the pulse broadening with first-order compensation in optical fiber systems were calculated and discussed. Furthermore, the pulse which is propagating with PMD compensation and without PMD compensation was compared here. The interaction of the PMD and nonlinearity was discussed. The coupled nonlinear Schrodinger equation and the Method of Split-step Fourier were used here. The light pulses which are propagating with PMD and nonlinearity are also simulated by solving the coupled nonlinear Schrodinger equation.