Synthesis of n-way active topology for wide-band RF/microwave applications

A simple circuit consisting of a linear differential amplifier IC chip and a few components is described which would provide the over-voltage and current protection for regulated power supplies. The circuit is also capable of providing under-voltage indication and both the over- and under-voltages can be preset by simple potentiometric adjustment.     

L频段150W固态连续波放大器设计

介绍了一种L波段150 W固态连续波功放的设计与实现。由于使用频带没有经济型的大功率功率管,设计过程中采用临近频带的大功率LDMOS功率管,采用动态阻抗匹配和ADS仿真相结合的方法进行跨频带匹配。采用微带巴伦进行分/合路,提高了模块的偶次谐波抑制,同时提高了模块的一致性。设计过程中采取了一系列的控制措施,提高模块的幅度相位一致性指标。制作调试了960~1 215 MHz频段150 W放大器,测试结果表明使用该方法设计放大器满足要求。     

半波对称振子天线的设计与仿真

该文设计了一种中心频率为2.4GHz的半波对称振子天线,其工作频率范围为2.3GHz～2.55GHz.利用电磁仿真软件Ansoft HFSS对此天线进行了仿真设计并进行了实验分析.通过设计“巴伦”解决了天线的馈电和阻抗变换问题,并对其回波损耗、驻波比、阻抗匹配以及远场增益的仿真结果进行了分析.结果表明,计算结果与仿真结果吻合良好.该天线基本满足设计要求,可用于移动通信基站天线.     

基于0.18-μm锗硅BiCMOS工艺的60 GHz匹配型高隔离小型化变压器巴伦

介绍了一种工作在60 GHz频率的具有输出端口间高隔离和全端口匹配特性的小型化变压器巴伦芯片,该芯片采用0.18-μm锗硅BiCMOS工艺设计并加工.通过在60 GHz变压器巴伦的输出端口之间引入隔离电路,提高巴伦的隔离度性能并改善输出端口匹配性能;在此基础上,提出了一种基于左手材料传输线的隔离电路,能大大改善传统隔离...     

电阻、扼流圈组成的平衡与非平衡之间阻抗转换器

文章介绍了一种用电阻和扼流圈组成的平衡与非平衡之间（以下简化为平衡←→专非平衡）阻抗转换器。该转换器具有制作简便、成本低廉、工作频带宽和较好的阻抗转换性能等优点。     

An UTRA/FDD Direct-Downconversion Mixer in 0.25 μm CMOS

In this paper the design of a 2 GHz direct-downconversion mixer for a UTRA/FDD receiver is presented. The mixer is implemented using a standard low-cost 0.25 m, single-poly, six-metal CMOS process. An on-chip passive balun is used to generate a balanced RF input signal. In-house optimized device models are used for both active and passive components to achieve a voltage conversion gain of 12.8 dB, an iIP₂ of 25 dBm, an iIP₃ of –3.1 dBm, and a noise figure of 8 dB. The circuit provides I and Q signal path outputs while drawing 6 mA from a 2.5 V supply.     

小型化介质加载方形四臂螺旋天线

本文采用了新的介质加载方法来设计卫星定位系统中手持机的天线。与传统的空心四臂螺旋天线相比,介质加载四臂螺旋天线的体积大大缩小,只有8mm*8mm*18mm,仿真结果表明,介质加载天线的增益为1.2dB,左右旋极化隔离度达到29dB,3dB轴比波束宽度为127度,前后比小于27.3dB。实测的设计频点处的回波损耗仅为-23.3dB,亦即驻波比VSW R=1.147。     

A novel model for a planar wideband Marchand balun

A new lumped element model for conventional Marchand baluns is presented.Analyzed by the evenand odd-mode method,the equivalent equations are derived forλ/4 coupled lines.Based on the proposed 5th-order lumped equivalent circuit forλ/4 coupled lines,the self-inductance,mutual inductive coupling and the capacitance can be calculated according to the even- and odd-mode characteristic impedance,therefore,the model parameters of the balun can be easily gained from the derived equations.To verify the model,a GaAs monolithic wideband Marchand balun was implemented and tested.The EM simulation and experimental results show a good agreement with the model simulation.This model is available in a wide frequency range and makes the design procedure of the Marchand balun faster and easier.     

GaAs pHEMT工艺6～18GHz有源倍频器MMIC

基于GaAs pHEMT工艺,设计了一个6～18 GHz宽带有源倍频器MM IC,最终实现了较高的转换增益和谐波抑制特性。芯片内部集成了输入匹配、有源巴伦、对管倍频器和输出功率放大器等电路。外加3.5 V电源电压下的静态电流为80 mA;输入功率为6 dBm时,6～18 GHz输出带宽内的转换增益为6 dB;基波和三次谐波抑制30 dBc。当输出频率为12 GHz时,100 kHz频偏下的单边带相位噪声为-143 dBc/Hz。芯片面积为1 mm×1.5 mm。     

双频带巴伦馈电的宽带双频印刷偶极子设计

研究一种巴伦馈电双频印刷偶极子天线。为了使印刷偶极子天线工作在WLAN 频段,H 形状的缝隙开在偶极子两个臂上。优化无巴伦馈电的辐射单元,使得天线在回波损耗小于-10 dB 的情况下工作在2.4 GHz (2180-2750 MHz)和5.2 GHz (5040-5480 MHz)。为了展宽带宽,本文设计了一种改进的Marchand 巴伦,它能提供两个谐振点以增加阻抗带宽。通过优化辐射单元和双频带巴伦,设计了工作在2150-2750 MHz 和5050-6230 MHz 的印刷偶极子天线。设计公式在文章中已经给出,计算和测试结果吻合得很好。