摘要
为了实现光标记交换(OLS)系统中频移键控(FSK)信号速率透明以及频率间隔可调,提出了一种基于偏振调制的频移键控(FSK)/幅移键控(ASK)联合正交调制OLS系统,其中FSK标记信号与ASK净荷信号的速率分别为1.25Gbit/s和20Gbit/s.通过仿真对该信号传输后的误码率(BER)特性及ASK净荷的消光比(ER)、FSK标记的频率间隔对系统性能的影响进行了分析.分析结果表明,增大FSK频率间隔对FSK信号的影响较小,但会恶化ASK信号;而增大ASK净荷的ER可改善ASK信号,但恶化了FSK信号.因此,最终选定ASK净荷ER和FSK标记频率间隔的最佳值分别为4dB和50GHz.
n order to realize the transparent bit rate and the tunable frequency of frequency shift keying （FSK） in the optical label switching （OLS） system, a new method is proposed and verified by simulation with 1.25 Gbit/s FSK label which is generated by polarization modulation and 20 Gbit/s amplitude shift keying （ASK） payload. The bit error rate （BER） performance of combined orthogonal FSK/ASK signal is also researched by simulation in the case of back-to-back and the fiber transmission. Besides, the ex- tinction ratio （ER） of ASK payload and the frequency spacing of FSK label have also been studied to ob- tain the better performance of this OLS system. It is indicated that larger frequency spacing of FSK label will deteriorate the ASK payload, but has little influence on FSK label; larger ER of ASK payload can improve the ASK payload, however, it will bring adverse impact on FSK label. As a result, the optimum ER of ASK payload and the most proper frequency spacing of FSK label are selected to be 4 dB and 50 GHz, respectively.
出处
《北京邮电大学学报》
EI
CAS
CSCD
北大核心
2010年第5期117-120,共4页
Journal of Beijing University of Posts and Telecommunications
基金
国家自然科学基金项目(60677004)
国家高技术研究发展计划项目(2007AA01Z260
2009AA01Z220)
教育部科学技术研究重点项目(107011)
关键词
光标记交换
频移键控
幅移键控
正交调制
偏振调制
optical label switching
frequency shift keying
amplitude shift keying
orthogonal modulation
polarization modulation
