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LIU Rong WANG Zheng PAN Wei-Min WANG Guang-Wei LIN Hai-Ying SHA Peng ZENG Ri-Hua 《中国物理C(英文版)》2009,33(7)
The new generation particle accelerator requires a highly stable radio frequency (RF) system. The stability of the RF system is realized by the Low Level RF (LLRF) subsystem which controls the amplitude and phase of the RF signal. The detection of the RF signal's amplitude and phase is fundamental to LLRF controls. High-speed ADC (Analog to Digital Converter), DAC (Digital to Analog Converter) and FPGA (Field Programmable Gate Array) play very important roles in digital LLRF control systems. This paper describes the implementation of real-time amplitude and phase detection based of the FPGA with an analysis of the main factors that affect the detection accuracy such as jitter, algorithm's defects and non-linearity of devices, which is helpful for future work on high precision detection and control. 相似文献
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针对"闪光二号"百kJ级储能型Marx发生器,设计了研究其建立时间和抖动的实验方案,根据发生器开关击穿模式的不同,分别研究了典型排的建立时间和抖动与Marx发生器建立时间和抖动之间的关系,研究了开关工作系数与Marx发生器及其典型排建立时间的关系。对Marx发生器建立时间、发生器第一排和第二排建立时间的实验测量表明:Marx发生器第一排建立时间对整个发生器的贡献大于60%,前两排建立时间对整个发生器的贡献大于73%;Marx发生器建立时间抖动主要来源于发生器第一排建立时间抖动,第一排建立时间和抖动则主要来自于气体火花开关的击穿时延抖动。根据实验结果,分析了影响建立时间抖动的主要因素,提出了减小建立时间抖动的措施。 相似文献
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We show the effect of varied order and width of super Gaussian pulse at 10 Gb/s in dispersion compensated optical communication system. The optical communication system consists of standard single-mode fiber of 16 ps/nm/km of a certain length, whose dispersion is compensated using pre-, post- and symmetrical-dispersion compensation schemes with proportionate length dispersion compensating fiber of −80 ps/nm/km. Performance of these three compensation schemes is compared at 14 dBm values of Er-doped fiber amplifiers (EDFA) power at 1st, 2nd and 3rd order RZ super Gaussian optical pulse. The pulse width, full width at half maximum (FWHM) is also varied from 5 to 30 ps to highlight the optimum performance. The graphical results obtained show a relationship among the attributes pulse width, order of RZ super Gaussian optical pulse and dispersion compensation scheme implemented. It shows that to decrease BER and timing jitter in the system, smaller width and 3rd order super Gaussian pulse should be used. It is recommended that to decrease dependency of BER and timing jitter in the communication system on the pulse width i.e. FWHM, the symmetrical compensation scheme should be implemented. 相似文献
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In this paper, the performance evaluation of path-averaged soliton transmission link for various performance measures viz. OSNR, optical power, extinction ratio, bit error rate (BER) and Q factor at different levels of noise figure and values of pulse width (FWHM) has been carried out. The performance of soliton transmission link is studied, taking into account soliton interaction, amplified spontaneous emission (ASE) noise and noise figure. The model presented considers interaction in a random sequence of solitons and the effect of the ASE noise added in each amplification stage. The influence of ASE noise, noise figure and pulse width with different amplifier spacing on the BER and quality factor has been investigated. It has been shown that these play dominant roles in degrading the performance measures. We have demonstrated the capability of path-averaged (guiding-centre) soliton for a long-haul distance of 17,000 km at a bit rate of 10 Gbps without ASE effect and noise figure in each amplifier span length of 500 km. The average value of quality factor is found to be 16.6 dB and the average BER is of the order of 10−12 over the transmission distance of 17,000 km. Further, it has been investigated that a severe system penalty results on the inclusion of ASE effect and noise figure in order to achieve the same level of performance. Thus, the investigations ascertain that in order to maintain the same level of BER and Q factor, the amplifier spacing and total transmission distance reduce considerably. 相似文献
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基于延迟抖动的流媒体传输QoS机制 总被引:1,自引:0,他引:1
着眼于流媒体的传输服务质量问题,研究给定网络条件下流媒体的自适应传输策略,提出了一种基于延迟抖动的流媒体传输QoS(Quality of Service)方法。仿真实验表明该方法能够迅速判断网络状态,使流媒体的数据传输与网络当前状态及时吻合,能够获得较低丢包率的同时获得较大数据传输 相似文献
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正在研制的Z箍缩实验装置(Z-pinch Primary Test Stand,PTS装置),由24个基于Marx发生器和水线的性能、结构相同的模块组成,各模块产生的大电流脉冲在绝缘堆上汇集后经磁绝缘传输线汇流到负载区,要求在不到0.2 Ω的低阻抗负载上得到8 MA以上电流,电流上升时间小于90 ns。研制的样机模块由Marx发生器、中间储能器、激光触发开关、脉冲形成线、水介质自击穿脉冲形成开关、三板型脉冲传输线组成,样机模块输出电流450 kA、输出电压2.2 MV、输出脉冲功率0.95 TW,从触发激光器信号输出到负载电压上升的系统延迟时间抖动小于6 ns。 相似文献
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多组多路输出100 kV快前沿电脉冲触发系统 总被引:4,自引:3,他引:1
在多路并联运行的电容储能型脉冲功率源中,为实现初级储能气体开关和脉冲形成主开关的同步,需要多组延时可调、每组多路输出的快前沿高电压脉冲来分别触发,为此研制了一套快响应低抖动100 kV快前沿电脉冲触发系统。该系统由同步机DG535和多组电脉冲放大单元组成,各组放大单元输出脉冲的延迟时间可调,延时步长由DG535设定,每组最短延时时间约为305 ns,抖动2 ns,可同时输出多路触发脉冲,在高阻负载上幅值可达180 kV,当输出信号为4路时,上升时间10 ns,当输出信号为8路时,上升时间15 ns。 相似文献
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