宽频带微带双工器的计算机辅助设计

一、前言在电子战系统中,往往要求将天线接收到的、复盖几个倍频程的宽带信号分隔成两个或多个波段,分别送到不同的接收机进行处理。这就需要采用双工器或多工器来进行分隔。早在60年代后期,国外就对于这种双工器理论进行了比较系统的研究。即采用单终端原型或缩减双终端原型来进行综合,设计高通——低通或带阻——带通滤波器相并联(或串联)构成互补双工器。两滤波器的输入导纳(或阻     

一种用于电力线载波通信的椭圆滤波器设计

针对电力线通信中LC无源滤波器体积大、元件参数不易确定等问题,阐述了利用GIC设计椭圆低通和高通滤波器的方法。利用Filter Solutions软件设计归一化椭圆低通滤波器,用GIC代替D元件或电感,经过频率变换和阻抗变换,得到实际的低通或高通滤波器。经过仿真,滤波器达到设计指标。该设计方法在某电力线载波通信门禁系统得到应用,使112～114 kHz的载波信号被完整提取,保证了系统的完整性能。     

用改进的电流传送器实现电流模式滤波器

本文提出了用四个改进的ＣＣⅡ器件实现二阶和一阶电流模式滤波器的新电路，为了验证理论分析的正确性，电路用ＰＳＰＩＣＥ程序进行了仿真，并且给了二价低通，带通，高通及一阶低通，高通，全通滤波器的计算机仿真结果，该电路具无源灵敏度低的特点。     

一种用于电力线载波通信的椭圆滤波器设计

针对电力线通信中LC无源滤波器体积大、元件参数不易确定等问题,阐述了利用GIC设计椭圆低通和高通滤波器的方法.利用Filter Solutions软件设计归一化椭圆低通滤波器,用GIC代替D元件或电感,经过频率变换和阻抗变换,得到实际的低通或高通滤波器.经过仿真,滤波器达到设计指标.该设计方法在某电力线载波通信门禁系统得到应用,使112～114kHz的载波信号被完整提取,保证了系统的完整性能.     

悬置梳状线双工器的理论设计与仿真

介绍了移动通信系统中双工器的设计原理和方法,此双工器是基于同一个低通滤波器模型的两个不同带宽和不同中心频率的悬置梳状线滤波器的组合.计算出了双工器的几何尺寸,并应用HP-ADS 仿真软件对此双工器进行了仿真和优化设计.     

运算放大器应用(續二)

19.滤波器利用运算放大器可以做成滤波器。一般来讲,采用LC滤波器能获得较好的特性和稳定性,然而为了获得更好的特性,就需要用很多元件,这样调整就困难些,同时其体积、重量均也加大。因此不适合用于晶体管电路。而当采用RC滤波器时,其特性就很差,特别在超低频中根本无法采用。在这种情况下,可以采用放大器和反馈电路组成的所谓有源滤波器。有源滤波器的特点为,以RC和放大器来组成低通滤波器、通带滤波器和阻带滤波器等。图22为运算放大器与二组RC电路组成的通带滤波器之一例。若放大器的增益(—A)     

升级的网络分析仪能应对多端口测量的挑战

无线电话的设计师正面临着继续增加新的频率覆盖范围、新的接入方法以及新功能的要求,而所有这些功能都须放进很小的芯片器件内。无疑,这已激发起人们努力对许多以往的分立功能进行集成,这导致了具有许多端口的射频元件的出现,而所有这些元件都必须加以测试。例如,当前的三波段电话前端中的天线开关模块包含了双工器、同向双工器和带通滤波器。天线开关模块可能有9个必须测量的端口,而早期的无线电话中,独立的双工器、同向双工器和带通滤波器需分别加以测量且最多为4个端口。 对多端口的器件进行测试,若每个端口必须手动测试、每次将电缆与各端口相连接和断开,将是一个艰苦的过程。为了显著减少进行这些测量所花的     

高通和低通滤波器对ADF谐波检测效果的研究

HVDC直流侧谐波电流的实时检测是直流有源滤波器(ADF)实现抑制谐波的重要环节。为获取有效电流信号，滤波器应该满足动态响应速度和测量精度的要求。本文研究了高通滤波器(HPF)和低通滤波器(LPF)对ADF谐波检测效果的影响，利用MATLAB仿真软件建立了相应的仿真电路，并就滤波器对谐波电流检测效果的影响进行了仿真研究，同时对两种电路的性能进行了对比。结果表明，谐波电流检测电路采用LPF，无论从设计上、可实现性上，还是从检测效果方面都有优势。     

双运放电压模式二阶通用滤波器的实现

视无限增益多路反馈低通滤波器为变形状态变量滤波器,用2个运算放大器、2个电容和4个电阻实现了电压模式二阶通用滤波器.该电路不仅可同时实现低通、带通和高通输出,具有低的无源灵敏度,而且其品质因数、极点角频率与电容比值和电阻比值有关,从而可实现二者的独立、精确调节,实现高精度滤波.此外,该电路中两运算放大器承受的共模电压为零,降低了对运放的要求,电路简单,适合VLSI单片集成技术.通过计算机仿真表明,所提出的电路方案是可行的.     

电压模式CCⅡ+/-双二阶滤波器

提出了一种用八个CCⅡ +/ -实现的电压模式双二阶滤波器结构 ,该结构用了两个电容和八个电阻。它无需改变输入电压和接地点的位置 ,可实现电压模式二阶低通、高通、带通、陷波和全通滤波特性 ,且各滤波电路的零点参数和极点参数均可独立调节。     

FULLY EMBEDDED COMPACT DIPLEXER INTO ORGANIC PACKAGE SUBSTRATE FOR DUAL-MODE (GSM/DCS) HANDSET APPLICATIONS

ABSTRACT

In this paper, a fully embedded compact diplexer has been designed, fabricated, and characterized for small size and low cost dual-mode (GSM/DCS) handset applications. The diplexer is fully embedded into an organic packaging substrate and remarkably reduced in size and volume by using high Q embedded circular spiral inductors and high dielectric MIM (metal-insulator-metal) capacitors. The fabricated diplexer has insertion losses and isolations of max. ?0.5 dB and min. ?35 dB at 880–960 MHz and max. ?0.9 dB and min. ?22 dB at 1710–1880 MHz, respectively. The fabricated diplexer is the smallest one of the diplexers formed onto organic substrate. It has 3.4 × 4.7 × 0.77 mm³ in volume.     

Updated structure of vertical double-diffused MOSFETs for irradiation hardening against single events

The gate oxide layer and parasitic bipolar junction transistor are inherent elements of vertical double-diffused power metal–oxide–semiconductor field-effect transistors (MOSFETs). Single-event gate rupture (SEGR) and single-event burnout (SEB) may be triggered by penetration of energetic ions through sensitive regions of such MOSFET devices when used in space environments. Based on the recombination mechanism in a heavily doped P+ buried layer and the higher breakdown voltage when using a thick oxide layer, a new structure for power MOSFETs that are irradiation hardened against SEGR and SEB was developed in this work, based on three typical characteristics: an N+ buried layer, a P+ buried layer, and a thick oxide above the neck. The results reveal that the safe operation region of such an N-channel power MOSFET in a single-event irradiation environment is enhanced by 300 % for a linear energy transfer value of 98 MeV cm²/mg. Such structures could be widely used when designing single-event irradiation-hardened power MOSFETs.     

一种紧凑结构的LTCC三路功分器

根据LTCC内埋电感的兀型等效电路,对传统Wilkinson功分器的集中参数模型进行了简化,提出了紧凑结构的LTCC结构三路功分器电路模型.根据该电路模型建立了三路功分器的三维LTCC模型,并进行了仿真计算.根据仿真优化结果制作了带宽中心频率为2.45GHz、大小为3.2× 1.6× 1.3mm的LTCC功分器.由于隔...     

FABRICATION AND CHARACTERIZATION OF FULLY EMBEDDED DIPLEXER AND BAND-PASS FILTERS FOR ORGANIC RF SOP APPLICATIONS

ABSTRACT

In this paper, fully embedded dual-band WLAN diplexer, 2.4 GHz WLAN BPF and wide-band pass filter are investigated into a multi-layered organic package substrate for low cost RF SOP (System on Package) applications. These embedded passive components were designed and analyzed by using ADS circuit simulator and CST 3D EM simulator for verifying their applicability. The fabricated diplexer and filters are the smallest one of the filters formed onto the organic substrate. The diplexer has a size of 3 mm × 2.5 mm × 0.77 mm and exhibits an insertion loss of max ?0.68 dB in 2.4 ～ 2.5 GHz band and max –3 dB in 5.15 ～ 5.32 GHz band, respectively. The 2.4 GHz BPF has a size of 2.7 mm × 2.1 mm × 0.77 mm and exhibits an insertion loss of max ?2.7 dB. The WBPF has a size of 3.2 mm × 2.5 mm × 0.77 mm and exhibits an insertion loss of ?2.65 dB. The major benefit of these embedded passive components, compared to a discrete solution, is a significant simplification and size/volume reduction of RF systems design.     

基于背离路径的输电断面搜索新算法

针对潮流转移引起的连锁过载跳闸问题,分析了过载支路切除后的潮流转移特征,指出受潮流转移影响较大的支路都集中在与切除支路电气距离较近的范围内;给出了一种快速搜索与过载支路相关输电断面的新算法,把实时的电力网络转化成拓扑图,采用基于背离路径的前K条最短路搜索算法,快速搜索出受潮流转移影响较大的输电断面,避免了采用单一路径搜索时因搜索范围过小而使部分支路漏选的情况,保证了输电断面的完整性。当发生过载时,可通过分析过载切除对输电断面内支路的影响来快速估计整个系统安全性的影响,极大地减少了分析计算的负担,有利于防止连锁过载跳闸的发生。最后对中国电力科学研究院(CEPRI)36节点系统进行仿真分析,验证了该算法的有效性。     

COMPLEX POWER IN CIRCUITS WITH MULTIPLE REACTIVE ELEMENTS

ABSTRACT

This paper provides a detailed discussion of how complex powers combine in circuits with multiple reactive or phase dependent elements. Reactive powers in different circuit elements are additive by simple addition if and only if either the currents or the voltages are in phase or 180° out; this condition is met by multiple elements on a given circuit branch, and by multiple circuit branches between common nodes. The phase condition is not met between individual reactive circuit elements on different circuit branches, therefore reactive power cannot be determined using simple addition; a more complex procedure is necessary. The results are of direct importance for properly determining energy storage between multiple circuit elements within an electrical grid.     

土壤直埋110 kV电缆中间接头稳态载流量仿真研究

针对目前没有成熟的交流电缆中间接头载流量校核方法,搭建了土壤直埋110 kV电缆中间接头和电缆本体稳态载流量三维仿真模型,利用有限元对比研究环境温度、土壤导热系数和敷设深度对电缆中间接头和本体稳态载流量的影响规律。结果表明：在不同环境温度、土壤导热系数和敷设深度下,电缆中间接头载流量始终小于电缆本体载流量,土壤导热系数为0.5 W·(m·K)^-1、环境温度为293 K以及敷设深度为1.75 m时的中间接头载流量相较于相同条件下的本体载流量减小了10.8%。因此,如按照电缆本体载流量校核电缆载流能力,将导致中间接头主绝缘处于加速热老化状态。为确保电缆长期稳定运行,建议以本体载流量确定电缆载流时应留有一定裕度。     

Effects of NOx and SO2 in cathode stream on the performance of PEMFC

Anegative effect of NOx,mainly NO2,onthe performance ofproton exchange membrane fuel cell(PEMFC)[1-3]was reported·The negative effects of NO2with concentrations ranging from4×10-5%(in volume,the same as follow)to 5×10-4%were re-ported to be reversible …     

Mode‐matching analysis and design of substrate integrated waveguide T‐junction diplexer and corner filter

The mode‐matching technique is deployed in this paper in order to analyze and design a substrate integrated waveguide (SIW) T‐junction diplexer in Ku‐band. The diplexer has bandwidths of 4.12% and 3.79% at 14.55 and 15.85 GHz, respectively. Also in Ku‐band, an SIW corner filter is analyzed and designed with the same technique. Analytical results are compared with simulated data obtained from commercially available field solvers such as CST Microwave Studio and ANSYS HFSS. Excellent agreement between analytical and simulated data is achieved. Copyright © 2014 John Wiley & Sons, Ltd.     

埋地式变压器在城市配网供电工程中的应用

随着城市的规划发展和城市电网改造的深入,安全、可靠与用电空间小的变、配电设备正得到越来越多的关注,地埋式变压器系列产品的出现适应了架空设备入地这一趋势,逐渐成为城网配线改造的一个新方向。它不仅节约了投资,而且能够美化城市环境。论述了埋地式变压器的基本技术及应用情况,比较了与常规配电设备的优缺点,提出今后在城市供电工程中埋地式变压器应做的改进。