Ultra-wideband balun and power divider using coplanar waveguide to microstrip transitions

An ultra-wideband transition from coplanar waveguide (CPW) to a pair of microstrip lines is presented in this letter. It is shown that the proposed transition can be used to devise an ultra-wideband T-junction power divider with equally split in-phase output signals. More importantly, it is demonstrated that the out-of-phase magnetic currents in the slots of the CPW can be utilized to achieve an out-of-phase power divider or a balun. Both the T-junction power divider and the balun benefit from compact size and good performance over an ultra wide frequency band from 3 to 16 GHz. Prototypes of both proposed devices are fabricated and measured to provide an experimental verification on the concept and numerically predicted features.     

一种宽频带双极化印刷偶极子基站天线

设计并优化了一款适用于LTE天线系统的基站天线振子单元。在印刷偶极子天线以及微带巴伦的基础上,通过等效电路模型进行分析,设计出该天线的多级阻抗匹配巴伦。采用寄生贴片、领结型设计等技术,有效地拓展了天线频带带宽,实现了±45°双极化。仿真结果表明,天线的VSWR≤1.5和回波损耗大于15 d B的带宽达到了54.5%,可以覆盖GSM1800,CDMA2000,WCDMA,TD-SCDMA和LTE系统。在此频带范围内,该天线的驻波特性、方向性、增益和隔离度等指标均满足LTE多模式系统的指标。同时该天线也易于制作,适用于LTE多模式基站天线系统。     

小型化三耦合线Marchand巴伦的等效模型分析与验证

为了实现三耦合线Marchand巴伦的快速设计,缩小巴伦的尺寸,提出了一种简化的三耦合线Marchand 巴伦等效模型及小型化设计方法。该等效模型将复杂的三耦合线的S参数散射矩阵的计算问题简化为对两个并联的平行耦合线的S参数散射矩阵的计算。为了验证该模型和设计方法的有效性,采用0.1 μm 砷化镓pHEMT (pseudomorphic High Electron Mobility Transistor)工艺制作了一款75~110 GHz的单平衡混频芯片,最终应用于单平衡混频器的巴伦耦合线长度被缩减为中心频率1/4波长的44%。良好的混频器性能和紧凑的芯片面积证明了所提三耦合线巴伦的等效模型和设计方法能够为单片集成微波电路芯片的设计提供指导作用。     

65-nm CMOS上带图案悬浮屏蔽的片上巴伦的特性

本文首先用一种简单的巴伦综合方法在工作频率范围内对巴伦结构进行估计,并借助电磁场仿真优化来检验估计的准确性,然后把优化后的巴伦（包括带屏蔽和不带屏蔽的两种情况）用于65-nm 1P6M CMOS工艺进行实现。测试结果显示图案悬浮屏蔽结构在频率范围内明显改善了插入损耗,并十分清晰地显示了线性改善的趋势。我们同样注意到图案悬浮屏蔽结构随着频率的增加逐渐改善了巴伦的相位平衡性,但对巴伦的幅度平衡性影响很小。为了得到器件本身的功率传输能力,我们提出一种方法从测得的三端口S参数直接获得巴伦的最大可用增益（Gmax）,并发现使用插入损耗比较的方式来检验屏蔽效果不是十分客观。另外阻性耦合效率也被用来衡量屏蔽效果。虽然图案悬浮屏蔽结构在测试中是完全对称的,但我们发现它对巴伦显示出不平衡的屏蔽效果。我们可以证明这种不平衡的屏蔽现象来自于巴伦本身的版图不平衡性。     

宽频带微带传输线巴伦的研究

对具有宽频带特性的微带传输线巴伦进行了研究,并应用微波网络优化理论对其进行了详细的理论分析与设计,数值计算结果与有关文献一致。最后,设计并制做了具有十倍频程的微带传输线巴伦,举例说明了本文方法的有效性。     

一种基于平面螺旋电感的不平衡变压器的设计

提出了一种基于0.13μm工艺,采用平面螺旋电感结构的宽带单片不平衡变压器。该电路的中心频率为23 GHz。在中心频率附近,模拟结果显示,单端口损耗为8 dB,在20~30 GHz频率范围内,两端口信号幅度误差为1 dB,相位误差为5°。     

Compact meta-material transmission line balun based on meander lines structure and MEMS technology

This paper presents a novel compact meta-structure microstrip balun, which is characterized by left-handed properties. In the novel structure, two coupled meander lines are used to generate series capacitor and series inductor. Compared with conventional composite right/left-handed transmission-line structures, the new structure has smaller size and is easily fabricated by MEMS (Micro Electromechanical Systems) technology. Using such a meta-structure, a wide band microstrip balun is designed and fabricated. Good performance in phase error in wide pass band has been achieved.     

一种采用印制线巴伦技术的1kW高功率放大器

介绍了一种P波段1kW微波脉冲功率放大器.功率合成方式采用印制线巴伦,从理论上简单地分析了这种印制线巴伦功率合成技术,阐述了印制线巴伦的应用,并将其实用化.功率器件采用的是具有高增益特性的功率LDMOS器件,实现了该放大器的高增益设计.这种放大器有效地降低了高功率、高增益放大器的尺寸和成本,功放功率大于900 W,增益大于20 dB,尺寸≤222 mm×82 mm×20 mm.     

20－44GHz 宽带倍频器单片集成电路的设计研究

摘要：本文采用0.15μm GaAs pHEMT工艺设计了输出信号带宽为20~44GHz的宽带倍频器。倍频器由三部分组成：将单端信号转换成差分信号的有源巴仑, 产生倍频信号的推－推结构的平衡倍频器和分布式放大器。输出信号功率在整个频段为12～17dBm。基波抑制比的典型值为－20dBc左右,该倍频器的偏置电压为±3.5V,直流电流为200mA。芯片的面积为1.5mm ×1.8mm。     

An ultra-wideband antenna for the reinforced concrete detection

In this paper, an Ultra-Wideband （UWB） planar antenna is proposed for the reinforced concrete detection, which consists of a pair of planar waterdrop arms, a microstrip to coplanar par- allel-strips transition and a shallow rectangular cavity. In order to overcome the disadvantages of the shallow cavity, some absorbing material is loaded to weaken the narrow-band effect of the cavity and the crosstalk interference. The simulated and measured results show that the proposed antenna has a large bandwidth from 0.48 GHz to 3.6 GHz with Voltage Standing Wave Ratio （VSWR） below 2 and a fractional bandwidth about 200% under the center frequency of 1.6 GHz, directional radiation char- acteristics and small late-time ringing in the time domain, which can be suitable for nondestructive detection of the reinforced concrete.