Intrinsic stability of an HBT based on a small signal equivalent circuit model

Intrinsic stability of the heterojunction bipolar transistor(HBT) was analyzed and discussed based on a small signal equivalent circuit model.The stability factor of the HBT device was derived based on a compact T-type small signal equivalent circuit model of the HBT.The effect of the mainly small signal model parameters of the HBT on the stability of the HBT was thoroughly examined.The discipline of parameter optimum to improve the intrinsic stability of the HBT was achieved.The theoretic analysis resul...     

基于AlGaN/GaN HEMT的C波段混合集成功率合成放大器的设计

研制了一种基于AlGaN/GaN HEMT的功率合成技术的混合集成放大器电路.该电路包含4个10×120 μm的HEMT晶体管以及一个Wilkinson功率合成器和分配器.在偏置条件为VDS=40V,IDS=0.9A时,输出连续波饱和功率在5.4GHz达到41.4dBm,最大的PAE为32.54%,并且功率合成效率达到69%.     

浅谈水利施工中各个步骤的应用

大中型水利工程施工牵涉的专业多、规模大、工序复杂,其施工组织设计对保证工程质量、缩短建设周期、降低工程造价、提高工程效益等都有十分重要的作用。文章结合一工程实例,阐述了流水作业法的基本原则、组织原则和一般步骤,供技术人员参考。     

GaAs MMIC用无源元件的模型

制作了不同结构参数的GaAs MMIC无源元件,包括矩形螺旋电感、MIM电容和薄膜电阻,建立了无源元件的等效电路模型库,采用多项式公式表征无源元件的模型参数和性能参数,便于电路设计的应用.并提取得到MIM电容的单位面积电容值,约为195pF/mm2,NiCr薄膜电阻的方块电阻约为16.1Ω/□.分析结构参数对螺旋电感性能的影响可知,减小线圈面积相关的寄生损耗有助于获得高品质的电感.     

A 6 GHz high power and low phase noise VCO using an InGaP/GaAs HBT

A 6 GHz voltage controlled oscillator (VCO) optimized for power and noise performance was designed and characterized. This VCO was designed with the negative-resistance (Neg-R) method, utilizing an InGaP/GaAs hetero-junction bipolar transistor in the negative-resistance block. A proper output matching network and a high Q stripe line resonator were used to enhance output power and depress phase noise. Measured central frequency of the VCO was 6.008 GHz. The tuning range was more than 200 MHz. At the central frequency, an output power of 9.8 dBm and phase noise of -122.33 dBc/Hz at 1 MHz offset were achieved, the calculated RF to DC efficiency was about 14%, and the figure of merit was -179.2 dBc/Hz.     

InGaP/GaAs HBT单管6GHz 大功率低噪声压控振荡器

A 6 GHz voltage controlled oscillator （VCO） optimized for power and noise performance was designed and characterized. This VCO was designed with the negative-resistance （Neg-R） method, utilizing an InGaP/GaAs hetero-junction bipolar transistor in the negative-resistance block. A proper output matching network and a high Q stripe line resonator were used to enhance output power and depress phase noise. Measured central frequency of the VCO was 6.008 GHz. The tuning range was more than 200 MHz. At the central frequency, an output power of 9.8 dBm and phase noise of-122.33 dBc/Hz at 1 MHz offset were achieved, the calculated RF to DC efficiency was about 14%, and the figure of merit was -179.2 dBc/Hz.     

基于不同器件结构的多指HBT热电稳定性研究

本文基于不同的器件结构同时对多指HBT器件的热稳定性和电稳定性进行了分析和讨论。通过直流测试、热阻计算以及基于S参数的稳定性因子K的计算,评估了两个不同版图结构的HBT器件的热稳定和电稳定特性,实验结果表明高热稳定性的器件具有低电学稳定性。引入一个基于小信号等效电路模型的K稳定因子公式对实验结果进行了合理解释。同时基于该公式,具有热镇流电阻结构的器件稳定性也进行了讨论。     

具有在片稳定网络的GaAs HBT微波功率管

采用GaAs标准MMIC工艺制作了具有片上RC并联稳定网络的InGaP/GaAs HBT微波功率管单胞.依据K稳定因子,RC网络使功率管在较宽的频带内具有绝对稳定特性.Load-pull测试表明RC网络没有严重影响功率管的大信号特性,在5.4GHz饱和输出功率为30dBm,在11GHz 1dB压缩点输出功率大于21.6dBm.功率合成电路验证了该功率管具有高稳定性,非常适合制作微波大功率HBT放大器.     

基于InGaP/GaAs HBT的X波段MMIC功率放大器研制

研制了X波段的InGaP/GaAs HBT单级MMIC功率放大器,该电路采用自行开发的GaAs HBT自对准工艺技术制作.电路偏置于AB类,小信号S参数测试在8～8.5GHz范围内,线性增益为8～9dB,输入驻波比小于2,输出驻波比小于3,优化集电极偏置后,线性增益为9～10dB.在8.5GHz进行连续波功率测试,在优化的负载阻抗条件下,P1dB输出功率为29.4dBm,相应增益7.2dB,相应PAE〉40%,电路的饱和输出功率Psat为30dBm.     

InGaP/GaAs HBT X波段混合集成功率合成放大器的研制

研制了面向X波段应用的InGaP/GaAs HBT混合集成功率合成放大器模块.电路采用一种新颖的具有片上RC稳定网络的InGaP/GaAs HBT功率管作为功率合成单元以提高电路的稳定性,并采用紧凑的微带线并联匹配网络进行功率分配和合成.在8.1GHz,偏置为Vcc=7V,Ic=230mA的AB类工作条件下,连续波最大输出功率为28.9dBm,功率合成效率达到80%.