论文部分内容阅读
无论是光路交换还是光突发交换,都离不开有光开关矩阵组成的光交叉连接节点(OXC)。OXC节点是组建波分复用光网络的基本单元,OXC节点引入的串扰成为限制其投入实用的主要原因。理论分析了基于扩展Benes(DB)结构和改进扩展Benes(GMDB)结构的三种典型OXC结构中的带内串扰,结果表明基于DB结构和GMDB结构的OXC节点可以完全消除低于二阶的各类串扰。数值模拟了基于两种结构的OXC节点中带内串扰的积累特性,发现基于GMDB结构的OXC节点能大大降低串扰引起的功率代价,实验测量了8×8DB结构和GMDB结构中串扰的影响,实验结果证实了GMDB结构的低串扰特点。同时与基于DB结构的OXC节点相比,基于GMDB结构的OXC节点对光开关串扰系数的要求放宽了5dB,大大降低了对光开关隔离度的要求。
Optical switching or optical burst switching can not do without the optical cross-connect node (OXC) consisting of a switched optical matrix. OXC nodes are the basic units for forming WDM optical networks. The crosstalk introduced by OXC nodes becomes the main reason that limits their practical application. The theoretical analysis of in-band crosstalk in three typical OXC structures based on the extended Benes (DB) structure and the improved extended Benes (GMDB) structure shows that the OXC nodes based on the DB structure and the GMDB structure can completely eliminate the Crosstalk. The numerical simulation of the accumulation of in-band crosstalk in OXC nodes based on two structures shows that OXC nodes based on GMDB structure can greatly reduce the power cost caused by crosstalk. The effect of crosstalk in 8 × 8DB structure and GMDB structure has been experimentally measured. The results confirm the low crosstalk characteristics of the GMDB structure. Compared with the OXC nodes based on DB structure, OXC nodes based on the GMDB structure relax the optical crosstalk coefficient by 5dB, which greatly reduces the requirements on optical isolation.