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1.
提出一种自适应线性化偏置的电路结构,通过调节控制电压改变偏置管的工作状态,提高功率放大电路的线性度,降低偏置电流对参考电压和环境温度的敏感度.利用双反馈环结构抑制输入阻抗随频率的变化,实现了宽带匹配,拓展了放大器的带宽.采用微波电路仿真软件AWR进行仿真,验证了带宽范围内的相位偏离度在2°以内.基于2μm InGaP/GaAs HBT工艺,设计了集成电路版图并成功流片.测试结果表明:在3.5V电压供电下,该放大器在1~2.5 GHz频带范围内,输入反射系数均在-10 dB以下,功率增益为23 dB,输出功率大于30 dBm,误差向量幅度在2.412 GHz时为.2.7%@24 dBm,最大功率附加效率达40%.  相似文献   

2.
提出了一种拓展带宽的新型电路拓扑结构,该结构由四级射极跟随器级联而成,通过自适应有源偏置电路调节各级晶体管跨导,以及改变级间电感与后一级射极跟随器的结电容Cbe谐振峰的频率位置来拓展带宽.对其工作原理和稳定性进行了分析,并基于2 μm InGaP/GaAs HBT工艺,设计了应用此结构的宽带放大器.仿真结果表明:新型电...  相似文献   

3.
Main amplifier, AGC amplifier, and preamplifier ICs have been designed and fabricated using an advanced silicon bipolar process to provide the required characteristics of repeater circuits for a gigabit optical fiber transmission system. The bipolar technology used involved a separation width of 0.3 /spl mu/m between the emitter and the base electrode. New circuit techniques were also used. The differential type main amplifier has a peaking function which can be varied widely by means of DC voltage supplied at the outside IC terminal. A bandwidth which can be varied to about three times the value for a nonpeaking amplifier is easily obtained. The gain and maximum 3-dB down bandwidth were 4 dB and 4 GHz, respectively. The main feature of the AGC amplifier is that the diodes are connected to the emitters of the differential transistor pair to improve the linearity. The maximum gain and 3-dB down bandwidth were 15 dB and 1.4 GHz, respectively, and a dynamic range of 25 dB was obtained. The preamplifier has a shunt-series feedback configuration. Furthermore, a gain and 3-dB down bandwidth of 22 dB and 2 GHz, respectively, were achieved with an optimum circuit design. The noise figure obtained was 3.5 dB.  相似文献   

4.
An optimum design of a low noise amplifier (LNA) in S-band working at 2-4 GHz is described. Choosing FHC40LG high electronic mobility transistor (HEMT), the noise figure of the designed amplifier simulated by Microwave Office is no more than 1.5 dB, meanwhile the gain is no less than 20 dB in the given bandwidth. The simulated results agree with the performance of the transistor itself well in consideration of its own minimum noise figure (0.3 dB) and associated gain (15.5 dB). Simultaneously, the stability factor of the designed amplifier is no less than 1 in the given bandwidth.  相似文献   

5.
An optimum design of a low noise amplifier (LNA) in S-band working at 2-4 GHz is described. Choosing FHC40LG high electronic mobility transistor (HEMT), the noise figure of the designed amplifier simulated by Microwave Office is no more than 1.5 dB, meanwhile the gain is no less than 20 dB in the given bandwidth. The simulated results agree with the performance of the transistor itself well in consideration of its own minimum noise figure (0.3 dB) and associated gain (15.5 dB). Simultaneously, the stability factor of the designed amplifier is no less than 1 in the given bandwidth.  相似文献   

6.
High power, high frequency linear distributed amplifiers are available commercially which provide high power single-ended drive capability from a single-ended source. The signal source can be either analog or digital. Such amplifiers must have stringent gain and phase response requirement over a wide bandwidth in order to maintain good eye quality of the signal. A limiting amplifier, with less stringent bandwidth requirement than analog amplifiers, can be used to amplify pure digital signal source. The purpose of this paper is to present a high power, fully differential limiting distributed amplifier operating at 10 Gb/s. The amplifier has been fabricated with both AlGaAs/GaAs and InGaP/GaAs heterojunction bipolar transistor (HBT) processes. The amplifier is designed to drive any 50 Ω system. In particular, this amplifier is intended to drive a III-V Mach-Zehnder modulator  相似文献   

7.
A monolithic wide-band amplifier for applications in counters from dc to UHF frequencies has been realized. The use of computer-aided design techniques, using a transistor model, and a broad-band feedback configuration has resulted in a monolithic amplifier that previously could only be constructed in hybrid form. This paper describes the development of a new high-frequency transistor model and a dc-coupled monolithic high-frequency amplifier that incorporates a final masking step option to obtain a maximally flat response over a 700-MHz bandwidth.  相似文献   

8.
提出了一种用于PDIC的跨阻放大器.电路由三级相同的推挽放大器级联而成,每级均采用一动态电阻对负载进行补偿,以提高放大器的相位裕度.反馈电阻由一栅极受控的PMOS管替代,避免了大尺寸多晶硅电阻引入的附加相移,增加了电路的稳定性.采用XFAB 0.6μm CMOS工艺提供的PDK,在Cadence Spectre环境下进行电路设计、仿真验证.仿真结果表明,电路的增益、带宽及稳定性均得到满意结果.
Abstract:
Presented is a transimpedance amplifier for PDIC.The designed amplifier is configured on three identical push-pull amplifier stages that use an active load compensated by an active resistor to improve the phase margin of the amplifier.The feedback resistor is replaced by a PMOS transistor which is biased by the gate voltage.The replacement not only avoids the phase-shift introduced by the large ploy-resistor but improves the stability performance of the transimpedance amplifier.Based on XFAB's 0.6 μm CMOS,circuit design and simulation were performed by using Cadence Spectre.The simulation results show that the gain,bandwidth and stability of the amplifier all achieve good performance.  相似文献   

9.
For a high-speed limiting amplifier with small phase deviation, a new design technique using a uniplanar passive balun and a narrow-band matching network is proposed. It is revealed that a device with small bias-dependence of parasitic capacitances, such as a high electron mobility transistor (HEMT), and a differential operation using passive baluns enables phase deviations at very high frequency to be reduced. Furthermore, suppressing harmonics can reduce phase deviation in a limiting amplifier, which operates in the highly nonlinear region. To verify these design techniques, two types of limiting amplifier ICs using an InP HEMT and AlGaAs/GaAs BCT technology were designed and fabricated. These IC's feature narrow-band matching circuits for input and output using transmission lines and uniplanar CPW-slot transition baluns for differential signals. The devices achieved high frequency operation of over 30 GHz with small phase deviations  相似文献   

10.
A four-stage silicon bipolar transistor power amplifier operating at centre frequency 9.25 GHz is reported. The amplifier has output power exceeding 1.0 W over an instantaneous bandwidth of approximately 800 MHz. The power-added efficiency of the amplifier is measured to be better than 18%.  相似文献   

11.
An ultrawide-band amplifier module has been developed that covers the frequency range from 350 MHz to 14 GHz. A minimum gain of 4 dB was obtained across this 40:1 bandwidth at an output power of 13 dBm. The amplifier makes use of negative and positive feedback and incorporates a GaAs MESFET that was developed with special emphasis on low parasitics. The transistor has the gate dimensions 800 by 1 mu m. The technology and RF performance of the GaAs MESFET are discussed, as are the design considerations and performance of the single-ended feed-back amplifier module.  相似文献   

12.
针对雷达发射多波束的需求,研制了一套基于氮化镓高电子迁移率晶体管三代半导体器件的增益可控固态放大器系统。描述了系统中微波放大模块、幅相控制和相位补偿的实现方案,分析了功率放大器栅极电压与放大器增益和输出信号相位的关系。通过幅相控制电路实现发射通道输出信号幅度和相位快速转换,满足发射多波束的需求。经试验验证,研制的大动态范围增益可控固态放大器系统,提高了效率和工作带宽,解决了传统发射多波束系统中的问题。  相似文献   

13.
The problem of wide bandwidth and flat in-band gain response for microwave transistor amplifiers has been reduced to the optimization of a number of important variables from computer prepared design charts. Through the general flexibility of the computer-generated data, a large variety of amplifier responses are possible using distributed circuit matching networks. As experimental verification of the overall design procedure, single-stage and two-stage octave wide transistor amplifiers were fabricated on 1inch by 1inch and 1inch by 1/2 inch 20 mil thick alumina, respectively. The experimental data gained from these units showed excellent correlation with the computer predicted response.  相似文献   

14.
The problem of wide bandwidth and flat in-band gain response for microwave transistor amplifiers has been reduced to the optimization of a number of important variables from computer prepared design charts. Through the general flexibility of the computer-generated data, a large variety of amplifier responses are possible using distributed circuit matching networks. As experimental verification of the overall design procedure, single-stage and two-stage octave wide transistor amplifiers were fabricated on 1 inch by 1 inch and 1 inch by 1/2 inch 20 mil thick alumina, respectively. The experimental data gained from these units showed excellent correlation with the computer predicted response.  相似文献   

15.
The problem of wide bandwidth and flat in-band gain response for microwave transistor amplifiers has been reduced to the optimization of a number of important variables from computer prepared design charts. Through the general flexibility of the computer-generated data, a large variety of amplifier responses are possible - using distributed circuit matching networks. As experimental verification of the overall design procedure, single-stage and two-stage octave wide transistor amplifiers were fabricated on 1 inch by 1 inch and 1 inch by ½ inch 20 mil thick alumina, respectively. The experimental data gained from these units showed excellent correlation with the computer predicted response.  相似文献   

16.
介绍了一种L波段150 W固态连续波功放的设计与实现。由于使用频带没有经济型的大功率功率管,设计过程中采用临近频带的大功率LDMOS功率管,采用动态阻抗匹配和ADS仿真相结合的方法进行跨频带匹配。采用微带巴伦进行分/合路,提高了模块的偶次谐波抑制,同时提高了模块的一致性。设计过程中采取了一系列的控制措施,提高模块的幅度相位一致性指标。制作调试了960~1 215 MHz频段150 W放大器,测试结果表明使用该方法设计放大器满足要求。  相似文献   

17.
Cascode amplifiers have three configurations: bipolar junction transistor-bipolar junction transistor (BJT-BJT), field-effect transistor (FET)-BJT, and FET-FET. Although the high-frequency behaviors of these configurations are not the same in practice, in most textbooks only the BJT-BJT configuration is analyzed. High-frequency response of the BJT-BJT cascode amplifier is limited by three factors: 1) the source impedance or the output impedance of the previous stage; 2) the output impedance or the load of the amplifier; and 3) the dc bias current of the amplifier. In order to cope with these limitations, this article presents a modified cascode amplifier. In this new configuration, only a single transistor is added to the elements of each of the aforementioned cascode amplifiers. Corresponding to each configuration, a modified configuration results in greater or approximately equal gain and higher bandwidth.  相似文献   

18.
An integrated bridge network of four transistors is used as a self-neutralized active element in tuned RLC amplifier designs. The bridge network compensates for the transistor collector-base junction capacitance (C/SUB c/), yielding a 95-percent reduction in the common-emitter reverse transmission admittance. IF amplifier stages that achieve the maximum unilateral power gain of a common-emitter transistor while maintaining excellent alignability are realized using the C/SUB c/ compensated transistor structure. Variations of the relative bias current levels of the transistors in the bridge network provides gain control by way of signal cancellation. This technique produces minimal frequency response variations of the amplifier stage being controlled. A noise analysis shows output signal to noise ratio at maximum attenuation can be a performance limitation.  相似文献   

19.
Three artificial transmission line sections followed by an input emitter follower buffer are used for constructing a new traveling wave matching structure to enhance the bandwidth of broadband amplifiers. An InGaP HBT MMIC broadband amplifier with 20-mW dc power consumption and a flat gain of 7.5dB over a frequency range from 30kHz to 23GHz is demonstrated.  相似文献   

20.
提出一种具有新型匹配网络的宽带高效率功率放大器,以及利用开路扇形微带线构成的紧凑型输出匹配网络,并给出了阻抗推导过程。该输出匹配网络在一定带宽条件下能满足晶体管的高效率所对应的阻抗设计空间要求。为了进一步拓展带宽,采用阶跃式阻抗匹配方法设计输入匹配网络。通过理论分析与仿真,最后设计并制作了一款频段为1~3.1 GHz的宽带高效率J类功率放大器。测试结果表明,在该频段内漏极效率为61.4%~70.2%,输出功率为39.3~41.7 dBm,增益为9.3~11.7 dB。  相似文献   

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