光栅不理想特性对不同调制码型的光传输系统的影响

分析了光纤光栅不理想特性的产生机理，对以啁啾光纤光栅为色散补偿器的10Gb/s光传输系统中，啁啾光纤光栅的不理想特性包括群时延纹波、反射纹波及光栅通带带宽对采用归零码(RZ)、非归零码(NRZ)以及载波抑制归零码(CSRZ)三种调制格式传输系统性能的影响进行了详细的数值分析和比较. 同时进行了基于光纤光栅色散补偿的1500km无误码传输实验，通过对啁啾光纤光栅由于不理想特性的差别而导致对实际传输系统不同信道性能影响的比较，进一步验证了仿真分析的正确性. 关键词： 光传输 啁啾光纤光栅 不理想特性 调制码型

Effects of nonideal characteristics of chirped fiber grating dispersion compensators on the system with different modulation formats

The causes leading to the nonideal characteristic of the chirped fiber Bragg grating (CFBG ) are discussed. The impact of the group delay ripple (GDR), reflectivity ripple (RR) and bandwidth of the CFBG on the 10Gb/s transmission system where non-return-to-zero (NRZ), return-to-zero (RZ) and carrier-suppressed return-to-zero (CSRZ) formats was investigated and the CFBG employed as dispersion compensator was simulated and compared in detail. The analytical result helps to optimize the practical 1500km CFBG-based transmission and the relation between the system performance and the nonideal characteristic of the grating validated the analysis in this paper.