一种超宽带零中频接收机的设计与实现

针对雷达、电子战和通信等多功能一体化探测要求,设计了一种基于零中频架构的0.3～18 GHz超宽带接收机。硬件系统由宽带数字接收机、超宽带模拟解调器和超宽带频率源组成,实现了0.3～2 GHz频段信号的直接数字化接收和2～18 GHz频段信号的模拟正交解调。给出了FPGA软件处理流程,采用了基于镜像功率检测方法对I/Q支路进行时延误差校正,采用了基于矩阵求逆最小方差法对I/Q支路进行幅相误差校正。样机测试结果表明,接收机的最大瞬时带宽为4 GHz,校正后的镜像抑制度超过50 dB。     

化学品供给、回收系统配管——FA管道安装工艺简述

介绍了在芯片工厂中,应用于化学品供给、回收系统的PFA管道安装工艺。     

键合互连对微波多芯片组件相位特性的影响

对键合互连对微波多芯片组件的相位特性影响进行了理论分析,并通过仿真软件HFSS对金丝键合互连模型进行了仿真。给出了在8~18 GHz的频率范围内,由于金丝拱高和跨距装配误差带来的相位误差。仿真分析表明,当金丝跨距在0.4~0.8 mm范围内波动时,最大相位差值在11 GHz以上时会超过20°,而当拱高在0.1~0.4 mm范围内波动时,最大相位差值在10 GHz以上时会超过20°,在13 GHz以上频率会超过30°。     

Quantitative evaluation of space charge effects of laser-cooled three-dimensional ion system on a secular motion period scale

In this paper,we introduce a method of quantitatively evaluating and controlling the space charge effect of a lasercooled three-dimensional(3 D) ion system in a linear Paul trap.The relationship among cooling efficiency,ion quantity,and trapping strength is analyzed quantitatively,and the dynamic space distribution and temporal evolution of the 3 D ion system on a secular motion period time scale in the cooling process are obtained.The ion number influences the eigen-micromotion feature of the ion system.When trapping parameter q is ~ 0.3,relatively ideal cooling efficiency and equilibrium temperature can be obtained.The decrease of axial electrostatic potential is helpful in reducing the micromotion heating effect and the degradation in the total energy.Within a single secular motion period under different cooling conditions,ions transform from the cloud state(each ion disperses throughout the envelope of the ion system) to the liquid state(each ion is concentrated at a specific location in the ion system) and then to the crystal state(each ion is subjected to a fixed motion track).These results are conducive to long-term storage and precise control,motion effect suppression,high-efficiency cooling,and increasing the precision of spectroscopy for a 3 D ion system.     

共面波导延迟线薄膜电路研制

基于薄膜电路工艺制作的共面波导延迟线不仅具有体积小、重量轻、损耗低、抗干扰性强等优点,还易与其他微波电路集成,延时精度较准。但它对高精度、密集孔薄膜电路的制作提出了更高的要求。通过优化薄膜电路制作工艺流程,研制出图形精度优于±5μm,具有良好金属化通孔的X波段两位延迟线薄膜电路。测试结果显示,该X波段两位延迟线的插入损耗为-5.7～-4.6 dB,带内起伏优于±0.3 dB,中心频率点相位偏差为±5°,满足设计要求。     

S波段25kW固态发射机的优化设计

介绍了该发射机的优化设计过程和全模块化设计思想,使复杂系统的设计变得简化、清晰。合理的模块化分解给系统的状态控制提供了可靠的数据依据。同时,它能使系统的调试分级进行,为发射系统的优化设计提供了保证。     

微波功率晶体管的激励功率选取

对于C类工作的固态微波功率管,降低工作电压是提高其可靠性的有效手段.文中就某功率管在工作电压降低的情况下,给出激励功率合理选择所必须考虑的综合因素:输出功率、工作效率、脉内顶降、增益平坦度.并给出影响工作效率、脉内顶降的物理分析和相应的实验数据.     

OLED实验线洁净室工程管理要点

说明为保证OLED的洁净生产环境所采取的各种措施及良好效果。     

Determining the structural phase transition point from the temperature of ~（40）Ca~＋ Coulomb crystal

We observed the linear-to-zigzag structural phase transition of a ^40Ca^＋ crystal in a homemade linear Paul trap. The values of the total temperature of the ion crystals during the phase transition are derived using the molecular-dynamics（MD） simulation method. A series of simulations revealed that the ratio of the radial to axial secular frequencies has a dependence on the total temperature that obeys different functional forms for linear and zigzag structures, and the transition point occurs where these functions intersect; thus, the critical value of the ratio of secular frequencies that drives the structure phase transition can be derived.     

一种超宽带耦合带线3dB耦合器设计

本文介绍了一种超宽带耦合带线3dB耦合器的设计.通过10%的加工公差仿真设计表明该种耦合器具有优良的性能.实际的设计结果在1.2～4.2GHz频带内插入损耗小于0.5dB,带内波纹大于-0.25dB小于 0.35dB,端口隔离大于17dB,端口驻波小于1.3.文章还对该种耦合器的峰值功率容量进行了分析,为其高功率应用提供了依据.