Composite second-order performance improvement in optical fibre CATV transmission system using chirped fibre grating
啁啾光纤光栅对光纤CATV系统中二阶非线性失真的改善

Theoretically, we analyze the dispersion compensation characteristics of the chirped fiber grating (CFG) in an optical fiber cable television (CATV) system and obtain the analytic expression of the composite second-order (CSO) distortion using the time-domain form of the field envelope wave equation. The obtained result is in good agreement with the numerical simulation result. Experimentally, we verify the result by making use of the tunable characteristics of CFG to change the dispersion compensation amount and obtain an optimal CSO performance in a 125-km fiber transmission link. Both the theoretical and experimental results show that the CSO performance can be improved by properly choosing the dispersion compensation amount for a certain fiber transmission link.