It includes the measurement of Raman gain spectra in DCF and G652, new design and set up of S+C band DFRA, measurement and analyze of performance and noise. The ideas of lowing down noise and improving performance are put forward.
包括对G652和DCF光纤的拉曼增益光谱的测量研究、S+C波段的分布式光纤拉曼放大器新的设计和实现、性能和噪声的测试和分析。
Meanwhile, comparison tests with EDFA show that DFRA has better performances when it is used as in-line amplifiers in the remote FOH system.
同时将分布式光纤拉曼放大器和掺铒光纤放大器进行了实验对比，结果表明前者可以作为远程光纤水听器系统的在线放大器，并且具有比后者更好的噪声性能。
Distributed Fiber Raman Amplifier (DFRA) magnify light signal directly by using transmitted fiber as gain medium.
分布式光纤拉曼放大器（DFRA）利用传输光纤本身作为增益介质来放大光信号。
With increasing DFRA on off gain, Δ OSNR increases first linearly and then logarithmically, resulting in saturation.
指出：随着DFRA开关增益的增加，ΔOSNR会由线性增加逐渐变为对数增加而趋于饱和。
Most strains show little sensitivity to streptomycin, erythromycin and polymyxin B, with the sensitivity of 1.0%, 6.0%and 3.3%.99.0%of the strains show resistance to more than two kinds of antibiotics.47.0%(140) of the strains show the same multi-drug resistant profiles, which are ampicillin, streptomycin, tetracycline, chloramphenicol, Sulfamethoxazole/Rimethoprim, nalidixic acid, erythromycin and kanamycin. Distribution of integrons shows that 64.3%of the Vibrio cholerae O139 strains contain the class 1 integron, and the class 2 and 3 integron was negative in Vibrio cholerae, and the class 4 of integron, also known as super-integron, are found in all strains.90.1%of the variable regions of the class 1 integron showed that there was only one gene cassette, such as aadA gene, but a small number of strains found the dfrA and arr-3 gene cassette. The gene sequencing of the topoisomerase resistance-determining region of these nalidixic acid resistant strains showed that:95.3%of the strains have two gene mutations, such as the 83 amino acid of GyrA and the 85 amino acids of ParC, In addition to the 83 amino acid mutation in GyrA and 85 amino acid mutation in ParC, 7 Ciprofloxacin-resistant strains have additional gene mutation, such as the 87 amino acids in GyrA from Asp into Asn and the 87 amino acids in ParE from Asp into Asn.
霍乱弧菌1类整合子阳性菌株中90.6%的可变区只有一个耐药基因，插入基因盒以aadA基因家族为主，7.8%菌株的可变区含dfrA12、orfF和aadA2共3个基因，另外还有2株菌含2个耐药基因arr-2和aadA3C，1株菌含3个耐药基因arr-3，dfrA27和aadA16.215株萘啶酸耐药菌株拓扑异构酶耐药决定区测序结果显示：95.3%的菌株都存在两个位点突变，即gyrA第248位碱基突变导致第83位氨基酸由丝氨酸变为异亮氨酸，parC第254位碱基点突变导致第85位氨基酸由丝氨酸Ser变为亮氨酸。8株环丙沙星耐药菌株中6株分离于2001年，在1998年和2006年各分离一株，除上述两个位点突变外，GyrA第87位氨基酸由天冬氨酸变为天冬酰胺，另外其中7株菌Pare第420位氨基酸由天冬氨酸变为天冬酰胺，还有1株环丙沙星耐药菌ParE第439位氨基酸由脯氨酸变为丝氨酸。
The DFRA researched in this paper is supported gravely by science and technology item Research and manufacture on Distributed Fiber Raman Amplifier of zhejiang province.
本论文结合浙江省科技厅重大科技项目《分布式光纤拉曼放大器的研制》来进行研究。
A transmission scheme of 2.5 Gbit/s over 250 km unrepeated span, which is based on the DFRA + EDFA hybrid amplification technology.
提出了基于DRFA+EDFA混合放大技术，实现传输速率为2.5Gbit/s、无中继距离为250km的传输技术解决方案。
DFRA and optimization on structure of product
DFRA与产品结构优化
Extending the Transmission Distance in Repeaterless Submarine Fiber Optic Cable with DFRA
用DFRA延长无中继海底光缆的传输距离