A monolithic DC temperature compensation bias scheme for multistageHEMT integrated circuits

This work benchmarks the first demonstration of a multistage monolithic HEMT IC design which incorporates a DC temperature compensated current-mirror bias scheme. This is believed to be the first demonstrated monolithic HEMT bias scheme of its kind. The active bias approach has been applied to a 2-18 GHz five-section low noise HEMT distributed amplifier which achieves a nominal gain of 12.5 dB and a noise figure <2.5 dB across a 2-18 GHz band, The regulated current-mirror scheme achieves better than 0.2% current regulation over a 0-125°C temperature range, The RF gain response was also measured over the same temperature range and showed less than 0.75 dB gain degradation. This results in a -0.006 dB/°C temperature coefficient which is strictly due to HEMT device G_m variation with temperature. The regulated current-mirror circuit can be employed as a stand-alone V_gs-voltage reference circuit which fan be monolithically applied to the gate bias terminal of existing HEMT ICs for providing temperature compensated performance, This monolithic bias approach provides a practical solution to DC bias regulation and temperature compensation for HEMT MMICs which can improve the performance, reliability, and cost of integrated microwave assemblies (IMAs) used in space-flight military applications     

Development of highly dense four-stage flat-gain 1-W 6-18-GHz MMICpower amplifier chip

A state-of-the-art dual-channel four-stage MMIC power chip operating over C-X-Ku bands has been produced. The chip, which is only 4.35 mm×5.1 mm, operates over 6-17 GHz with very small gain ripple. At 25°C each one of its channels provides 29.5±0.5 dBm at 2-dB compression (2 dBc) from a small-signal gain of 19.5±1.5 dB. The drain bias is 7 V. and the power added efficiency is 11-14%. At 85°C, power and gain decrease by 0.5-1 and 3.5-4 dB, respectively. The design was iterated once to produce an all-monolithic amplifier chip that operates over the full 6-18-GHz frequency band and provides more than 1 W at 18 GHz. The architecture and size were maintained in the iterated design. The excellent power and gain ripple performances of the C-X-Ku chip extended to 18 GHz with a small-signal gain reduction of 0.5-1 dB. The chip is designed for use with inputs and outputs coupled externally for additional 2-2.5 dB of power. Excellent performance over 6-18 GHz was achieved using Lange couplers on 10-mil alumina     

具有正斜率增益的GaAs MMIC宽带放大器芯片设计

介绍了一种宽带放大器芯片,该放大器的工作频率覆盖了2～12 GHz,采用砷化镓(GaAs)赝配高电子迁移率晶体管(PHEMT)单片电路工艺实现。在一个宽带负反馈放大器的前面集成了一个幅度均衡器,使放大器的增益在整个带内具有7 dB的正斜率,频率低端(2 GHz)增益为3 dB,高端(12 GHz)为10 dB,输入输出电压驻波比为1.6∶1,饱和输出功率为20 dBm,芯片尺寸为2.0 mm×1.5 mm×0.1 mm。详细描述了电路的设计流程,并对最终的测试结果进行了分析。该芯片具有频带宽、体积小、使用方便的特点,可作为增益块补偿微波系统中随着频率升高而产生的增益损失。     

A 20 GHz Band 0.5 W GaAs FET Amplifier for Satellite Communications

GaAs FET amplifier modules for 20 GHz band satellite communications have been developed using newly developed power FETs. The deep recess gate structure was adopted in the power FET, which improved both power output capability and power gain. Power added efficiency of 22 percent with more than 1 W power output has been achieved with 3 mm gate width FETs. The amplifier modules containing two-stage internally matched FET's can be hermetically sealed in metal packages. The modules had 8.4-8.9 dB linear gain in the 17.7-18.8 GHz band and 7.9-8.4 dB linear gain in the 18.5-19.6 GHz band. The power output at 1 dB gain compression point was more than 0.5 W. The third-order intermodulation distortion ratio was 81-83 dB at 18.2 GHz and 77-80 dB at 18.9 GHz, when individual output signal power was -4 dBm.     

A W-band image-rejection downconverter

The design, fabrication, and evaluation of a W-band image-rejection downconverter based on pseudomorphic InGaAs-GaAs HEMT technology are presented. The image-rejection downconverter consists of a monolithic three-stage low-noise amplifier, a monolithic image-rejection mixer, and a hybrid IF 90° coupler with an IF amplifier. The three-stage amplifier has a measured noise figure of 3.5 dB, with an associated small signal gain of 21 dB at 94 GHz while the image-rejection mixer has a measured conversion loss of 11 dB with +10 dBm LO drive at 94.15 GHz. Measured results of the complete image-rejection downconverter including the hybrid IF 90° coupler and a 10 dB gain amplifier show a conversion gain of more than 18 dB and a noise figure of 4.6 dB at 94.45 GHz     

A W-band monolithic downconverter

The design, fabrication, and evaluation of a fully integrated W-band monolithic downconverter based on InGaAs pseudomorphic HEMT technology are presented. The monolithic downconverter consists of a two-stage low-noise amplifier and a single-balanced mixer. The single-balanced mixer has been designed using the HEMT gate Schottky diodes inherent to the process. Measured results of the complete downconverter show conversion gain of 5.5 dB and a double-sideband noise figure of 6.7 dB at 94 GHz. Also presented is the downconverter performance characterized over the -35°C to +65°C temperature range. The downconverter design was a first pass success and has a high circuit yield     

A K-Band GaAs FET Amplifier with 8.2-W Output Power

An 8.2-W GaAs FET amplifier with 38.6+-0.5-dB gain over a 17.7-19.1 GHz frequency band has been developed. This amplifier combines the outputs of eight multistage amplifier modules utilizing a radial combiner. This state-of-the-art power level has been achieved with AM/PM of less than 2°/dB. The third-order intermodulation products at 1-dB gain compression were 20 dBc, and variation in group delay over the frequency band was less than +-0.25 ns. Tests show that the amplifier is unconditionally stable and follows the graceful degradation principle.     

Prediction of Wide-Band Power Performance of MESFET Distributed Amplifiers Using the Volterra Series Representation

The power performance of a four-section MESFET distributed amplifier is predicted over the frequency range 2-8 GHz. The nonlinear model of the MESFET used has three nonlinear elements: g/sub d/, and C/sub gs/, which are represented by power series up to the third order. The analysis employs the Volterra series representation up to the third order. Experimental verification is first made on a 0.5x400-µm medium-power MESFET device to confirm the validity of the nonlinear model used in the analysis. The agreement between predicted and measured output power at 1-dB gain compression is within +-0.5 dBm across the 2-16 GHz band. A four-section distributed amplifier was then built with four 0.5x400-µm MESFET's. The agreement between predicted and measured output power at 1-dB gain compression of this amplifier is within +-0.7 dBm across the 2-8-GHz band. The measured output power at 1-dB gain compression is (22+-1) dBm across the 2-8-GHz band.     

A high-performance 2—18.5-GHz distributed amplifier—Theory and experiment

A high-performance 2-18.5-GHz monolithic GaAs MESFET distributed amplifier has been designed and fabricated. The distributed amplifier is analyzed theoretically using a normalized transmission matrix approach, and a closed-form gain equation is presented for the MMIC m-derived drain-line case. Theoretical predictions are compared to measured results and more complicated CAD models. The measured small, signal gain is typically 8.0±0.40 dB from 2-18.5 GHz at standard bias. Typical input return loss is greater than 12 dB, and the output return loss is greater than 15 dB. The saturated output power is in excess of 23 dBm over most of the band, and the noise figure is less than 7.5 dB.     

A 22-GHz-band low-noise down-converter for satellite broadcastreceivers

A simple low-cost and high-performance 22 GHz band down-converter developed for a direct-to-home satellite broadcasting system is discussed. The down-converter consists of a low-noise high electron mobility transistor (HEMT) preamplifier, an image recovery mixer with a particular structure using dielectric resonator filters, a 21.4 GHz GaAs FET oscillator stabilized by a dielectric resonator, and an IF amplifier. These components are fully integrating using microwave integrated circuit technology into a small size. A total noise figure of less than 2.8 dB is obtained over the 22.5-23.0 GHz frequency range. The local oscillator achieves a frequency variation of less than 600 kHz_p-p over a temperature range of -20° to +60°C     

110-120-GHz monolithic low-noise amplifiers

The authors discuss the development of 110-120-GHz monolithic low-noise amplifiers (LNAs) using 0.1-mm pseudomorphic AlGaAs/InGaAs/GaAs low-noise HEMT technology. Two 2-stage LNAs have been designed, fabricated, and tested. The first amplifier demonstrates a gain of 12 dB at 112 to 115 GHz with a noise figure of 6.3 dB when biased for high gain, and a noise figure of 5.5 dB is achieved with an associated gain of 10 dB at 113 GHz when biased for low-noise figure. The other amplifier has a measured small-signal gain of 19.6 dB at 110 GHz with a noise figure of 3.9 dB. A noise figure of 3.4 dB with 15.6-dB associated gain was obtained at 113 GHz. The authors state that the small-signal gain and noise figure performance for the second LNA are the best results ever achieved for a two-stage HEMT amplifier at this frequency band     

2～20GHz分布式单片放大器设计

介绍了一种采用0.15μm GaAs PHEMT工艺设计加工的2～20 GHz宽带单片放大器,为了提高电路的整体增益和带宽,在设计电路时采用两级级联分布式结构。此种电路结构不仅能够增加整体电路的增益和带宽,还可以提高电路的反向隔离,获得更低的噪声系数。利用Agilent ADS仿真设计软件对整体电路的原理图和版图进行仿真优化设计。后期电路在中国电子科技集团公司第十三研究所砷化镓工艺线上加工完成。电路性能指标:在2～20 GHz工作频率范围内,小信号增益>13.5 dB;输入输出回波损耗<-9 dB;噪声系数<4.0 dB;P-1>13 dBm。放大器的工作电压5 V,功耗400 mW,芯片面积为3.00 mm×1.6 mm。     

7.9?8.4 GHz GaAs m.e.s.f.e.t. amplifier

A 4-stage balanced GaAs m.e.s.f.e.t. amplifier has been developed for the 7.9?8.4 GHz satellite-communication frequency band. Linear gain of 26±0.5dB and 150 mW power at 1 dB compression were obtained across the design band. The small-signal gain, phase linearity, group delay and noise figure are described as a function of frequency. Large-signal gain saturation, 3rd-order intermodulation distortion, gain and phase against temperature and a.m.-to-p.m. conversion data are also presented.     

6～18GHz宽带功率放大器模块

研究了ＧａＡｓ功率ＭＥＳＦＥＴ的小信号特性、大信号特性和其宽带匹配网络。选用ＴＷＴ－２型功率器件，设计研制出了单级宽带功率放大器。在６～１８ＧＨｚ的工作频率范围内，小信号增益等于５．０±１．０ｄＢ，１ｄＢ压缩输出功率等于２５．０±０．８ｄＢｍ，输入输出驻波比小于２．５。     

L波段砷化镓单片低噪声放大器

设计、研制了一种工作在Ｌ波段的ＧａＡｓ单片低噪声放大器。该放大器在ＨＰ－８５１０Ｂ网络分析仪和ＨＰ－８９７０Ｂ自动噪声仪上的测试结果为：１．１～１．５ＧＨＺ频段，ＮＦ≤２．０ｄＢ，Ｇ≥１８ｄＢ，ＶＳＷＲ（ｉｎ，ｏｕｔ）≤２：１，增益起伏≤０．５ｄＢ；在１．５～２．０ＧＨＺ频段ＮＦ≤２．５ｄＢ，Ｇ≥１８ｄＢ，ＶＳＷＲ（ｉｎ，ｏｕｔ）≤２：１，增益起伏≤±０．５ｄＢ。     

全离子注入C波段功率单片放大器及内匹配功率单片放大器

报道了全平面C波段功率单片放大器及四单片合成放大器研究结果。单片放大器采用全离子注入工艺，均匀性好，平均成品率40％，可靠性高。工作频率4．7—5．2GHZ，中心频率5．0GHz处输出功率2．5W，增益15dB，功率附加效率31．5％。单片放大器芯片面积2．8mm×2．0mm，四路合成的4×MMIC频率范围不变，中心频率4．95GHz处输出功率8．2W，增益13dB，功率附加效率26％，四路合成效率接近80％。实验结果与理论预测基本吻合。     

A W-band InAs/AlSb low-noise/low-power amplifier

The first W-band antimonide based compound semiconductor low-noise amplifier has been demonstrated. The compact 1.4-mm/sup 2/ three-stage co-planar waveguide amplifier with 0.1-/spl mu/m InAs/AlSb high electron mobility transistor devices is fabricated on a 100-/spl mu/m GaAs substrate. Minimum noise-figure of 5.4dB with an associated gain of 11.1 dB is demonstrated at a total chip dissipation of 1.8 mW at 94 GHz. Biased for higher gain, 16/spl plusmn/1 dB is measured over a 77-103 GHz frequency band.     

2～6GHz单片功率放大器

报道了有耗匹配宽带单片功率放大器的研究方法和结果。该两级单片功放电路采用自建的 Root非线性模型进行了谐波平衡分析。在 2 .0～ 6.7GHz频带上线性增益为 17d B,平坦度为± 0 .75d B,输入和输出驻波分别小于 2。全频带上 ,饱和输出功率为 1～ 1.4 W,功率附加效率大于2 0 %。该宽带单片功率放大器在 76mm Ga As单片 MMIC工艺线上用全离子注入、0 .5μm栅长工艺研制完成 ,电路芯片面积为 0 .1mm× 2 .6mm× 2 .7mm。     

A 77 GHz mHEMT MMIC Chip Set for Automotive Radar Systems

A monolithic microwave integrated circuit (MMIC) chip set consisting of a power amplifier, a driver amplifier, and a frequency doubler has been developed for automotive radar systems at 77 GHz. The chip set was fabricated using a 0.15 µm gate‐length InGaAs/InAlAs/GaAs metamorphic high electron mobility transistor (mHEMT) process based on a 4‐inch substrate. The power amplifier demonstrated a measured small signal gain of over 20 dB from 76 to 77 GHz with 15.5 dBm output power. The chip size is 2 mm × 2 mm. The driver amplifier exhibited a gain of 23 dB over a 76 to 77 GHz band with an output power of 13 dBm. The chip size is 2.1 mm × 2 mm. The frequency doubler achieved an output power of –6 dBm at 76.5 GHz with a conversion gain of ?16 dB for an input power of 10 dBm and a 38.25 GHz input frequency. The chip size is 1.2 mm × 1.2 mm. This MMIC chip set is suitable for the 77 GHz automotive radar systems and related applications in a W‐band.     

Design of a 24-40 GHz balanced low noise amplifier using Lange couplers

A wide band(24-40 GHz)fully integrated balanced low noise amplifier(LNA)using Lange couplers was designed and fabricated with a 0.15/zm pseudomorphic HEMT(pHEMT)technology.A new method to design a low-loss and high-coupling Lange coupler for wide band application in microwave frequency was also presented.This Lange coupler has a minimum loss of 0.09 dB and a maximum loss of 0.2 dB over the bandwidth from 20 to 45 GHz.The measured results show that the realized four-stage balanced LNA using this Lange coupler exhibites a noise figure(NF)of less than 2.7 dB and the maximum gain of 30 dB;moreover,a noticeably improved reflection performance is achieved.The input VSWR and the output VSWR are respectively less than 1.45 and 1.35 dB across the 24-40 GHz frequency range.