排序方式: 共有71条查询结果,搜索用时 15 毫秒
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提出了基于RS码(Reed-Solomon Code)的光码分多址(OCDMA)系统的前向纠错编码方案,仿真分析了该方案对一维、二维OCDMA系统的纠错能力.研究结果表明:对于相同码长、相同码重光地址码的OCDMA系统,采用前向纠错(FEC)技术能够有效降低系统误码率,提高系统客量,改善系统性能.对于来自同一码族的OCDMA系统,随码重增加,系统性能改善越好.Abstract: A novel forward error-correct (FEC) scheme based on Reed-Solomon code (RS code) is proposed for optical code division multiple access (OCDMA) systems.The error-correcting ability of the presented FEC scheme for one-dimension and two-dimension OCDMA systems are simulated and analyzed.Researched results show that the bit error rate (BER) of OCDMA system using FEC technology is better than that withoutwit using FEC technology at the condition of same code length and code weight.And the capacity is also largely enhanced due to the application of FEC technology.Moreover,for the address code of OCDMA system coming from the same code family,the BER is improved with the increase of the code weight. 相似文献
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The generation of optical millimeter waves via the improved phase modulator in a RoF system and the transmission character of the signal are theoretically investigated. A new phase modulating scheme is proposed, in which the sidebands are separated by wave length demultiplexer and one of them doesn't feed digital signals, thereby the phase wake-off is restrained. 相似文献
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分布拉曼放大器(DRA)的增益轮廓平坦度是衡量放大器性能的一个重要指标.文章通过实验验证了泵浦方式及入射信号功率对增益轮廓的重要影响作用.实验采用20信道符合ITU-T建议的波分复用(WDM)信号,波长从l537.377(信道1)~l560.605nm(信道20),每一信道用2.5Gbit/s、码长2^7-1的非归零码通过电吸收调制器(EA)进行外调制.实验结果对分布拉曼放大器的增益轮廓平坦优化具有实际参考价值. 相似文献