超宽带有源匹配FET反馈放大器的分析与设计

本文提出用广义S参数设计有源匹配FET反馈放大器的方法，给出了共源、共栅、共漏反馈电路单元的广义S参数计算公式。最后举例说明了共栅－共漏和共栅－共源－共漏放大器的优化设计方法。     

微波晶体管放大器的非单向化设计

一般微波晶体管放大器的单向化设计是基于S12＝0的假设，而实际上放大器的S12≠0。若进行放大器设计时，从一开始就考虑放大器的S12项，则是放大器的非单向化设计。本文介绍了放大器的非单向化设计及其方法。     

微波集成MESFET放大器的灵敏度分析与设计

本文介绍一种计及MESFET S参数灵敏度的微波集成放大器的灵敏度分析方法;定义了放大器特性的频带灵敏度和电路灵敏度,它们可作为选择低灵敏度电路的一个综合判据。最后介绍一种具有低灵敏度特性的微波集成MESFET放大器的设计方法,并给出了算例。     

反向传输对微波放大器的影响

本文分析了微波晶体管反向传输参数S12≠0的情况下，用理想器件代替实际器件进行放大器设计时，反得转换功率增益的误差。     

3.6~4.7GHz低噪声放大器

以一种经典的窄带低噪声放大器结构为基础,分析级联放大器的S参数,通过优化元件参数,获得了一种在3.6~4.7 GH z范围内具有低输入回波损耗、低噪声系数的放大器。采用标准的0.18μm RF CM O S工艺进行了设计和实现。芯片面积为0.6 mm×1.5 mm。测试结果表明:在3.6~4.7 GH z的范围内,该宽带低噪声放大器输入回波损耗小于-14 dB;噪声系数小于2.8 dB,增益大于10 dB。在1.8 V电源下功耗约为45 mW。     

单管单元MOS RAM读出放大器的瞬态分析与设计

本文定义一个电流灵敏度函数S(t)来描述单管单元RAM读出放大器的灵敏度,它比较形象地描绘了读出放大器到达自锁这一瞬态过程。利用计算机模拟计算,可以改变各种设计因素(器件参数、位线预充电电平,φ_S上升波形……等)来观察它们对于S(t)函数曲线特征的影响,并以此作为最佳化设计的依据,直观地获得设计参数。本文还对读出放大器的设计提出了若干改进建议。     

四公分低噪声场效应晶体管放大器

本文介绍四公分低噪声场效应晶体管放大器的初步研制结果,通过对晶体管S参数的测试进行电路设计。制成两级级联放大器作为接收机低噪声前端。在实验室内实现的指标是:放大器的噪声系数小于4.3分贝,放大器增益为14分贝。文中同时介绍了放大器所能承受的射频脉冲功率及实验数据。     

2.4 GHz、增益可控的CMOS低噪声放大器

介绍了一种基于 0 35 μmCMOS工艺、2 4GHz增益可控的低噪声放大器。从噪声优化、阻抗匹配及增益的角度详细分析了电路的设计方法 ,讨论了寄生效应对低噪声放大器性能的影响。仿真结果表明在考虑了高频寄生参数的情况下 ,低噪声放大器依然具有良好的性能指标 :在 2 4GHz工作频率下 ,3dB带宽为 6 6 0MHz,噪声系数NF为 1 5 8dB ,增益S2 1为 14dB ,匹配参数S11约为 - 13 2dB。     

C波段固态微波功率放大器的设计

本文介绍了C波段固态微波功率放大器的宽带设计方法,即利用小信号S参数和切比雪夫型低通滤波阻抗变换技术;同时给出了根据该方法设计成功的放大器的实例及其试验和测试结果。最后就国内外在研制微波晶体管方面的现状及其发展趋势进行了简要的介绍。由于固态放大器特有的优良性能,该放大器代替小功率行波管应用于雷达发射机中,将使雷达性能进一步提高。     

场效应晶体管微波参数测量

本文介绍了用作图法测量场效应晶体管的噪声参数,用网络分析仪测量散射参数(s参数)的方法。给出了国产WC50型低噪声砷化镓场效应晶体管在C波段的噪声参数及在C、S波段的s参数。用测出的s参数设计的C波段场效应晶体管放大器获得了初步良好的结果。     

Analytical expressions for simplifying the design of broadband lownoise microwave transistor amplifiers

An analytical expression for the minimum achievable noise figure for a specified gain at a given frequency is derived for a microwave amplifier. The minimum noise figure is given in terms of the specified gain, the amplifier noise parameters, and the S-parameters. Similarly, another expression for the maximum gain at a specified noise figure is derived in terms of the noise figure, the noise parameters, and the S-parameters. It is shown that these expressions simplify the tradeoff considerations for broadband low noise amplifier design by avoiding the need to draw several constant noise and gain circles at each frequency of interest     

Analysis and Design of the 0.13- $muhbox{m}$ CMOS Shunt–Series Series–Shunt Dual-Feedback Amplifier

This paper demonstrates the design methodology of the shunt–series series–shunt dual-feedback Meyer wideband amplifier. The small-signal S-parameters are obtained for the first time using the pole-and-zero analysis, thus giving the RF designers a detailed insight into the Meyer amplifier. A 10-GHz wideband amplifier is demonstrated in this paper, using 0.13-${rm mu}hbox{m}$ CMOS technology to verify our design theory. The experimental results of the S-parameters highly agree with our theory.      

Modeling the bias and temperature dependence of a C-class MESFETamplifier

In this paper, a complete bias and temperature-dependent large-signal model for a MESFET is determined from experimental S-parameters and dc measurements. This model is used in the analysis of the performance of a C-class amplifier at 4 GHz over a -50° to 100°C temperature range and for different bias conditions. The dependencies of the elements of the equivalent circuit, as well as the amplifier gain on the temperature and the operating point, are evaluated. The gain optimization and the analysis as a function of temperature of the MESFET amplifier are done by using the describing function technique. Optimum bias device conditions in the C-class are obtained for maximum gain and also the flattest gain versus input power rate. A comparison between theoretical and measured results over temperature and bias ranges is shown. Experimental results show an excellent agreement with the theoretical analysis     

Millimeter-wave CMOS circuit design

We have developed a 27- and 40-GHz tuned amplifier and a 52.5-GHz voltage-controlled oscillator using 0.18-mum CMOS. The line-reflect-line calibrations with a microstrip-line structure, consisting of metal1 and metal6, was quite effective to extract the accurate S-parameters for the intrinsic transistor on an Si substrate and realized the precise design. Using this technique, we obtained a 17-dB gain and 14-dBm output power at 27 GHz for the tuned amplifier. We also obtained a 7-dB gain and a 10.4-dBm output power with a good input and output return loss at 40 GHz. Additionally, we obtained an oscillation frequency of 52.5 GHz with phase noise of -86 dBc/Hz at a 1-MHz offset. These results indicate that our proposed technique is suitable for CMOS millimeter-wave design     

Two-Signal Method of Measuring the Large-Signal S-Parameters of Transistors

In this paper, large-signal S-parameters are reviewed, and transistors of Class-C are employed. Problems are encountered in obtaining large-signal parameters S/sub 12/ and S/sub 21/. A novel method is concisely developed based on theory presented herein. The acquired S-parameters are applied to amplifier design accordingly. The predicted and measured output power are compared, and suitable conclusions are duly recorded.     

Unconditional Stability of a Three-Port Network Characterized with S-Parameters

An analytical solution is presented which establishes nine conditions necessary for determining the unconditional stability of a network described with three-port S-parameters. In contrast to the unconditional stability conditions of a two-port network the unconditional stability conditions of a three-port network are dependent on both the three-port S-parameters and the port terminations. These criteria form the basis for three-port amplifier design, and are used to analyze measured three-port S-parameter data of a silicon BJT at 2.4 GHz.     

The determination of S-parameters from the poles of voltage-gain transfer function for RF IC design

A method for estimating the S-parameters of active circuits using hand analysis is introduced. This method involves the determination of S-parameters from the poles of voltage-gain transfer function. It is found that the information on the frequency responses of input/output return loss, input/output impedance, and reverse isolation is all hidden in the poles or equivalently in the denominator of the voltage-gain transfer function of a circuit system. The method has been applied to three commonly used RF circuit configurations and one fabricated CMOS wide-band amplifier to illustrate the usefulness of the proposed theory.     

Q-band (26?40 GHz) GaAs FET single-stage amplifier

The high-frequency S-parameters of a 0.3 ?m-gate-length GaAs FET have been measured and compared with the device equivalent circuit model. From the data a Q-band single-stage low noise (3.1 dB) amplifier was designed.     

跨阻放大器S参数与跨阻增益间的关系

在等效电路模型基础上,推导了单端输入单端输出和单端输入差分输出情况下跨阻放大器跨阻增益计算公式,探讨了光探测器输出阻抗对跨阻增益的影响,分析了电路S参数与跨阻增益的关系。并且利用ADS仿真工具对理论推导进行了仿真验证,最后通过实验测量单端输入单端输出跨阻放大器的S参数及数据分析,对理论进行了验证。     

A 40-Gb/s Transimpedance Amplifier in 0.18-$mu$m CMOS Technology

A 40-Gb/s transimpedance amplifier (TIA) is realized in 0.18-mum CMOS technology. From the measured S-parameters, a transimpedance gain of 51 dBOmega and a 3-dB bandwidth up to 30.5 GHz were observed. A bandwidth enhancement technique, pi-type inductor peaking (PIP), is proposed to achieve a bandwidth enhancement ratio (BWER) of 3.31. In addition, the PIP topology used at the input stage decreases the noise current as the operation frequency increases. Under a 1.8 V supply voltage, the TIA consumes 60.1 mW with a chip area of 1.17 X 0.46 mm2. The proposed CMOS TIA presents a gain-bandwidth product per DC power figure of merit (GBP/P_de) of 180.1 GHzOmega/mW.