特高压电网超长距传输新方向:塔内光中继

针对特高压电网建设对超长距传输提出的更高要求,提出了新的技术方向——塔内光中继。分析了塔内光中继的理论依据并设计了技术方案,在哈密郑州特高压直流输电光纤通信工程石城至环县段实现了我国首个塔内光中继实验工程,工程顺利开通,运行稳定,验证了塔内光中继方案的可行性。随着我国电网建设的不断发展,塔内光中继将得到更广泛的应用

521km超长站距无中继光传输系统研究

文章介绍了利用新型SMF-28ULL超低损耗光纤作为传输介质,使用相位啁啾、前向拉曼、增强型前向纠错（FEC）以及前置随路远程泵浦光放大（ROPA）技术,实现了2.5Gbit/s系统无中继521km的超长站距传输,这也是迄今所报道的使用前置随路ROPA技术所实现的距离最远的传输

一种基于多步插值的频偏估计法

提出了一种基于多步插值的频偏估计算法,用于相干光通信中数字相干接收机的频偏估计补偿。该算法首先采用少量的数据点作FFT（快速傅里叶变换）,粗估计出频偏值,然后采用DFT（离散傅里叶变换）进行多步插值计算,降低了计算复杂度。在一个28GBaud的QPSK（正交相移键控）仿真系统中进行了仿真验证,结果表明,与最新报道的LS（最小二乘）算法相比,该文所提算法可以大大降低现有算法的复杂度

高速光纤通信系统中DBP算法的步长选择

文章提出了一种新的应用于高速光纤通信系统接收端的数字背向传输（DBP）算法的步长变换选择方法。通过采用斜线方法对光纤非线性系数的指数形式曲线进行近似,找出使斜线的斜率与原曲线各点斜率差值最小情况下的步长,再用于变步长DBP算法中对光纤传输中的非线性损伤进行补偿。在3 200km单信道25Gbaud光纤传输系统中对所提步长选择方案进行了仿真。结果表明,在相同系统中,与其他步长选择方法相比,在最佳入纤功率时所提步长选择方案的Q值提升了0.5dB;当入纤功率越大、非线性效应越强时,所提方法对于光纤传输非线性损伤的补偿能力更好,而算法复杂度没有改变

联合在束γ装置的发展和实验

简要介绍了联合在束 γ装置 ,经过十多年实验和发展的基本概况 ,以及最近使用 10套 BGO(AC)HPGe探测器在北京 HI- 13串列加速器上进行了 12 8Te+19F、NZr+19F、115In+3 5Cl反应的首批实

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies