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51.
采用切比雪夫低通原型滤波器综合法,设计了一种半波长开路谐振器平行耦合滤波器,该类型滤波器具有插入损耗低、结构简单、容易实现等诸多特点。从测试结果看出,实际测试值与理论分析及MWO软件仿真结果基本一致。 相似文献
52.
A dynamic beam propagation model of micro-vibrating spatial filters in inertial confinement fusion(ICF) facilities is built based on the additional beam in SG-II facility.The transfer matrix is then deduced,and the sensitivities of the beam positioning to the pellet in the target area to the vibrations of every spatial filter are analyzed,which indicates that the vibrations of spatial filters in the pre-amplify zone has less effects on beam positioning stability at the target.In addition,the vibrations of spatial filters in the main amplify zone dominates the beam positioning stability of the target,especially the vibration of the spatial filter SF7. 相似文献
53.
A demultiplexing scheme based on semiconductor optical amplifier(SOA)and optical filter for optical time division multiplexing differential quadrature phase shift keying(OTDM-DQPSK)system is proposed and investigated experimentally.With only a common half baudrate electrical clock modulated 33%duty cycle return-to-zero(RZ-33)optical clock signal as pump,this scheme is cost-effective,energy-efficient,and integration-potential.A proof-of-concept experiment is carried out for the demultiplexing of a 2×40-GBd OTDM-DQPSK signal.Error-free performance is demonstrated,and the average power penalty for both channels is about 3 dB. 相似文献
54.
Surface photovoltage spectroscopy equations for cathode materials with an AlxGa1-x As buffer layer are determined in order to effectively measure the body parameters for transmission-mode (t-mode) photocathode materials before Cs-O activation.Body parameters of cathode materials are well fitted through experiments and fitting calculations for the designed AlxGa1-x As/GaAs structure material.This investigation examines photo-excited performance and measurements of body parameters for t-mode cathode materials of different doping structures.It also helps study various doping structures and optimize structure designs in the future. 相似文献
55.
A software synchronous optical sampling system is constructed based on sum frequency generation (SFG) in periodically poled lithium niobate (PPLN). Five gigahertz of a non-return-to-zero (NRZ) data signal is sampled by sampling pulse with the repetition frequency of 29.31 MHz. The power of the SFG light is set at 23 dBm, and an eye diagram is successfully recovered. A band-pass filter is added before the sampling pulse is subjected to erbium-doped fiber amplifier to reduce gain competition and ensure a high power level of SFG. 相似文献
56.
57.
提出了一种基于局部反馈校正的无重置联邦滤波器的设计方法,该联邦滤波器在保证组合导航系统的容错性能不变的同时可以提高系统的导航精度。该方法用于船用组合导航系统设计中,通过计算机仿真,并同Carlson提出的无重置联邦滤波器的仿真结果相比较,表明该方法精度高、容错性好,该方法现已成功应用于船用组合导航系统设计中。 相似文献
58.
In order to avoid stimulated Brillouin scattering and smooth the final focal spot that reaches the D-T capsule, spectral broadening is essential. However, the modulation of spectral structure might result in frequency-to-amplitude modulation (FM-to-AM) conversion. The spatial filter pinhole is used to cut off the high-frequency transmission laser, and to ensure the desired pass. Improper parameter of pinhole would lead a negative impact. Using the spatial filter pinhole, we analyze the characteristic of intensity modulation using several pinholes of improper parameters. We then compare these results with the intensity modulation obtained from an experiment. Experimental diagnosis and design of an appropriate pinhole parameter would be highly beneficial to the field of high-power lasers. 相似文献
59.
提出了一种二维正交小波滤波器逼近的方法,采用分步优化的方法来构造小波滤波器,最后通过实验给出低通的小波滤波器. 相似文献
60.
收稿考滤了一类多带正交对称小波滤波器对应多相矩阵分解结构,系统地构造了一类具有自由参数多带小波滤波器簇,以4带小波为例得到了用参数角表示的一类正交对称滤波器序列. 相似文献