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1.
The importance of high-performance,low-cost and millimeter-wave transmitters for digital communications and radar applications is increasing.The design and performance of a Ka-band balanced in-phase and quadrature-phase(I-Q)type vector modulator,using GaAs heterojunction bipolar transistors(HBTs)as switching elements,are presented.The balanced technique is used to remove the parasitics of the HBTs to result in near perfect constellations.Measurements of the monolithic microwave integrated circuit(MMIC)chip with a size of 1.89×2.26 mm~2 demonstrate an amplitude error below 1.5 dB and the phase error within 3°between 26 and 40 GHz except for a singular point at 35.6 GHz.The results show that the technique is suitable for millimeter-wave digital communications.  相似文献   
2.
我们制造出了栅长为88 nm的InP基InAlAs/InGaAs 高电子迁移率器件(HEMTs),该器件的频率特性为ft = 100 GHz, fmax = 185 GHz。本文对横向栅槽宽度分别为300 nm, 412 nm, 1070 nm的器件进行了实验。借助能带图的方式,定性分析了横向栅宽的增加会因为表面态和碰撞电离的作用,使得器件直流特性表现出kink效应,并得到减小横向栅槽宽度能减弱kink效应的结论,文中还讨论了横向栅槽宽度通过改变器件寄生电容及其源漏电阻,从而对频率特性产生影响。这些分析对制造出更高性能的HEMT器件有比较重要的意义。  相似文献   
3.
A large signal model for InP/InGaAs double heterojunction bipolar transistors including thermal effects has been reported,which demonstrated good agreements of simulations with measurements.On the basis of the previous model in which the double heterojunction effect,current blocking effect and high current effect in current expression are considered,the effect of bandgap narrowing with temperature has been considered in transport current while a formula for model parameters as a function of temperature has been developed.This model is implemented by Verilog-A and embedded in ADS.The proposed model is verified with DC and large signal measurements.  相似文献   
4.
A two-stage MMIC power amplifier has been realized by use of a l-μm InP double heterojunction bipolar transistor(DHBT).The cascode structure,low-loss matching networks,and low-parasite cell units enhance the power gain.The optimum load impedance is determined from load-pull simulation.A coplanar waveguide transmission line is adopted for its ease of fabrication.The chip size is 1.5×1.7 mm~2 with the emitter area of 16×1μm×15μm in the output stage.Measurements show that small signal gain is more than 20 dB over 75.5-84.5 GHz and the saturated power is 16.9 dBm @ 79 GHz with gain of 15.2 dB.The high power gain makes it very suitable for medium power amplification.  相似文献   
5.
正An 88 nm gate-length In_(0.53)Ga_(0.47)As/In_(0.52)Al_(0.48)As InP-based high electron mobility transistor (HEMT) was successfully fabricated with a gate width of 2×50μm and source-drain space of 2.4μm.The T-gate was defined by electron beam lithography in a trilayer of PMMA/A1/UⅧ.The exposure dose and the development time were optimized,and followed by an appropriate residual resist removal process.These devices also demonstrated excellent DC and RF characteristics:the extrinsic maximum transconductance,the full channel current, the threshold voltage,the current gain cutoff frequency and the maximum oscillation frequency of the HEMTs were 765 mS/mm,591 mA/mm,-0.5 V,150 GHz and 201 GHz,respectively.The HEMTs are promising for use in millimeter-wave integrated circuits.  相似文献   
6.
SDD定义的InP DHBT大信号模型   总被引:1,自引:1,他引:0  
A self-built accurate and flexible large-signal model based on an analysis of the characteristics of InP double heterojunction bipolar transistors (DHBTs) is implemented as a seven-port symbolically defined device (SDD) in Agilent ADS. The model accounts for most physical phenomena incluuing the self-heating effect, Kirk effect, soft knee effect, base collector capacitance and collector transit time. The validity and the accuracy of the large-signal model are assessed by comparing the simulation with the measurement of DC, multi-bias small signal S parameters for InP DHBTs.  相似文献   
7.
A W-band frequency doubler MMIC is designed and fabricated using 1-μm InP DHBT technology. Active balun is employed to transform the single-ended signal into differential output. Push-push configuration loaded with harmonic resonant network is utilized to acquire the second harmonic frequency. A multi-stage differential structure improves the conversion gain and suppresses the fundamental frequency. The MMIC occupies an area of 0.55×0.5 mm2 with 18 DHBTs integrated. Measurements show that the output power is above 5.8 dBm with the suppression of fundamental frequency below -16 dBc and the conversion gain above 4.7 dB over 75-80 GHz.  相似文献   
8.
88 nm栅长fmax=201 GHz InP基In0.53Ga0.47As/In0.52Al0.48As HEMT器件   总被引:1,自引:1,他引:0  
我们成功研制了栅长88 nm, 栅宽2 50 μm, 源漏间距为2.4 μm 的InP基In0.53Ga0.47As/In0.52Al0.48As高电子迁移率器件(HEMT)。栅是使用PMMA/Al/UVⅢ,通过优化电子束曝光时间及其显影时间的方式制作的。这些器件有比较好的直流及其射频特性:峰值跨导、最大源漏饱和电流密度、开启电压、ft和fmax 分别为765 mS/mm, 591 mA/mm, -0.5 V, 150 GHz 和201 GHz。这些器件将非常适合于毫米波段集成电路。  相似文献   
9.
对于雷达通信高性能,低成本的毫米波发射机显得尤为重要。Ka波段(26.5GHz~40GHz)基于GaAs HBT工艺,以HBT为开关器件的平衡式I/Q调制器的成功研制。采用平衡式拓扑可以有效的消除由于HBT电容所带来的寄生,从而达到较高性能的星座图。此芯片面积是1.89x2.26mm2,测试的幅度和相位的误差在26~40GHz间除了35.6GHz的单点外,分别小于1.5dB和3度。测试的结果可用于毫米波通信。  相似文献   
10.
AW-bandtwo-stageamplifierMMIChasbeendevelopedusingafullypassivated 2 × 20 μm gate-width and 0.15 μm gate-length InP-based high electron mobility transistor (HEMT) technology. The two-stage amplifier has been realized in combination with a coplanar waveguide technique and cascode topology, thus leading to a compact chip-size of 1.85 × 0.932 mm^2 and an excellent small-signal gain of 25.7 dB at 106 GHz. Additionally, an inter-digital coupling capacitor blocks low-frequency signal, thereby enhancing the stability of the amplifier. The successful design of the two-stage amplifier MMIC indicates that InP HEMT technology has a great potential for W-band applications.  相似文献   
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