VHF宽带E类高效率功率放大器设计

使用ADS(Advanced Design System)软件仿真设计了基于28-V MOSFET器件的VHF频段30 MHz～80 MHz E类开关模式高效率功率放大器。输入端使用了宽带匹配,输出端通过开关改变后端的匹配电路和滤波器。电路实测:30 MHz～80 MHz输出功率3.2 W～7.1 W,效率从30 MHz的71.4%到80MHz的52.5%,并且具有优良的调幅线性度,可以将其应用到EER发射机。     

S波段E类功率放大器的设计

开关模式E类功率放大器的理论效率可达100%,可用于天气雷达发射机系统中。采用GaN HEMT器件,设计了一个在2.8 GHz频点下的E类功率放大器,输出功率达到40 dBm,PAE为67%,增益为13 dB。此外,设计的微带负载网络对谐波进行了有效抑制。     

模拟预失真射频功率放大器设计

本文介绍了一种WCDMA频段模拟预失真功率放大器的设计。在设计中采用预失真技术对幅度一幅度（AM—AM）和幅度一相位（AM—PM）曲线进行校正,以补偿功率放大器的非线性失真。实现了在输出功率为39dBm时信号带宽内偏离第一个5MHz信道的ACPR值优于-53dB。     

动态偏置射频宽带功放设计

射频宽带功率放大器是目前功率放大器的主要发展趋势。为了提高射频宽带功率放大器的增益平坦度与效率,采用推挽结构LDmos晶体管,使用ADS软件对动态偏置电路和匹配电路进行仿真设计。详细介绍了动态偏置功率放大器的工作原理及其实现方法。实现了多倍频程带宽、确保带内增益平坦、提高功率附加效率。仿真结果表明该功率放大器对于100MHz~400MHz的信号,在整个输入功率变化范围内,功率附加效率（PAE）与传统的功放相比提高了5~15%左右。     

平衡功率放大器的设计与实现

设计了一个工作频段为902MHz～928MHz、输出功率为32dBm、应用于读卡器系统的末级功率放大器。为了在工作频段内实现平坦的功率增益并获得良好的输入、输出驻波比,本功率放大器采用平衡放大技术设计。仿真优化和实际测试表明,在整个工作频段内放大器的增益平坦度小于±0.5dB,输入、输出驻波比小于1.5,完全满足设计指标要求。     

一种480MHz无线数传模块的设计

针对中国智能电网开放的免费无线计量频段,设计了一种可工作在470 MHz～510 MHz、中心频率为480 MHz、输出功率可调的无线数传模块。模块采用MSP430F2274单片机和射频芯片CC1100E设计,利用EDA软件ADS2008仿真优化了射频电路的输出匹配网络。最后对无线模块输出功率、通信距离等参数进行了测试和验证。     

基于小信号S参数的MOSFET射频功率放大器设计

介绍了如何利用场效应管的小信号散射(S)参数设计射频功率放大器,并采用此设计方法,选用场效应管,设计了一种工作在160 MHz频段的金属氧化物半导体场效应管(MOSFET)功率放大器.在工作频段内,功率放大器增益大于23 dB,输入端口的匹配网络的回波损耗S11优于-19 dB.实例证明:该设计方法仿真简单,易于实现,具有重要的工程应用价值.     

E类射频功率放大器设计

基于0.18μm CMOS工艺,采用包含增益驱动级在内的两级电路结构,设计了一个工作频率为2.4GHz的E类开关模式功率放大器,并实现了全片集成.电路通过负载牵引技术获得最佳输出负载,在2V电源电压下经ADS2005A仿真,当输入信号功率为-10dBm时,获得约21.5dBm的输出功率,功率增益为31dB,功率附加效率达到57.69%的较好结果.     

基于北斗卫星通信的射频收发系统设计

我国海上的导航、定位、电台、勘探等应用和业务都与北斗卫星密切相关,但由于海上气候条件恶劣,海面的不平坦性以及特殊的地理和电磁特性等原因,会对北斗卫星的信号产生严重的影响。本文设计了一款轻量化、低功耗、高性能的多频段射频前端系统。该设备由1615MHz、2004MHz两路发射和1575MHz、1176MHz两路接收单元组成。在放大功率、隔离度等各项设计参数满足指标的同时,还具备输出功率可调、功率放大器开关可控、驻波比告警等功能。设备位于天线与终端设备之间,实现基于北斗卫星系统的海上通信,提供稳定可靠的通信链路。     

驱动级功率放大器的设计与实现

设计了一个工作频段在902 MHz～928 MHz,输出功率为19 dBm、功率增益高达27 dBm、应用于射频识别(RFID)系统的驱动级功率放大器。为缩短功率放大器的研发周期并提高其开发的成功率,设计运用了仿真优化和实际测试相结合的方法。测试结果与仿真结果的高度一致性验证了这种方法的有效性。     

A high efficiency inductor‐less broadband fully integrated CMOS power amplifier

This work presents the design and implementation of a novel broadband completely inductor‐less 300 MHz–2.4 GHz power amplifier (PA) in 180 nm CMOS, primarily for applications in the ultrahigh frequency (UHF) industrial scientific and medical band. This is capable of delivering up to 15.6 dBm saturated output power with an associated peak power added efficiency of 31% in measurement. Although amplifiers with higher output power have been reported, this amplifier occupies only 0.086 mm² and does not require any off chip component for its operation, even at the UHF band. It also achieves the highest power density among a similar class of PA's below 10 GHz. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:311–320, 2015.     

用于UHF RFID的功率放大器设计

功率放大器是UHF RFID系统的重要模块,也是RFID系统中功耗最大的器件。本文采用TSMC0.18rf CMOS工艺,设计了一款用于RFID的线性功率放大器。在915 MHz频段,最大输出功率为17.8 dBm,饱和效率达到了40%,输出1 dB压缩点(P1dB)为15.4 dBm,其小信号增益达到了28.7 dB。     

Highly efficient switched‐mode transmitter using a current mode class‐D RF amplifier

This article presents a switched‐mode transmitter architecture using a current mode class‐D (CMCD) amplifier. To achieve high average efficiency for a modulated signal the envelope of the complex baseband signal is transformed into pulses such that the CMCD amplifier is operated either at its peak efficiency or completely switched off. The CMCD amplifier has been designed based on single‐tone active harmonic load‐pull measurements to achieve a power‐added efficiency (PAE) of 61.5% with 25 W output power at 900 MHz using LDMOS FETs. Removing the losses of the demodulation filter and of the amplifier a 10% higher efficiency than in an ideal class‐B amplifier can be obtained for burst‐mode operation with a peak‐to‐average power ratio of 10 dB. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.     

Class-E self-oscillation for the transmission of wireless power to implants

This paper develops the concept of Class-E self oscillation for wireless power delivery to implantable sensors with the comparison of several topologies. Power amplifiers and oscillators are considered as two separate blocks in wireless power transmission. By combining these topologies into a self-oscillating power transmitter, greater efficiency can be achieved. Various topologies are compared with measured hardware results, determining that a crystal feedback network provides both accuracy and high power output. A new crystal feedback Class-E self oscillator has been implemented by transmitting power through 2 cm-thick biological tissue. The paper includes a second order modelling and design process that can be used to design a Class-E self oscillator as an inductive power transmitter as well as measured results.     

基于E类放大器的电容耦合电能传输系统参数研究

由于接触式电能传输方式在转轴扭矩测试等特殊环境下使用的局限性,无线电能传输技术越来越受到国内外研究者的重视.分析了E类放大器在电容耦合电能传输系统的工作原理.在E类放大器与CLC调谐电路模型的基础上,基于E类放大器中开关管的零电压开关(ZVS)与零电压变化率开关(ZDS)条件,采用粒子群算法,设计出电路中的各个参数的最优解,并建立电容耦合电能传输系统的电路模型.应用Muhisim电路仿真软件对设计结果进行验证.仿真结果表明:该模型有效提高了机构的带负载能力.     

Broadband Doherty power amplifier with improved band‐pass auxiliary network

In this article, a Doherty power amplifier (DPA) with improved band‐pass auxiliary impedance inverter is proposed for broadband operation. As a wideband DPA solution, the output matching networks of main and auxiliary devices are designed to achieve proper impedance matching at back‐off and peak power by employing a two‐point matching technique without the λ/4 impedance transformer. It is found that the modified band‐pass network has broader bandwidth feature and is compact in form from the comparison with some different topologies of matching networks. So, it is more suitable to be the auxiliary transformer to achieve the broadband configuration of DPA. For validation purpose, a Doherty power amplifier based on two commercially available gallium nitride HEMT (Cree CGH 40010F) devices was designed, fabricated, and measured. Under the drive of continuous wave (CW) signal, the measurement results show that the DPA has a 6‐dB back‐off efficiency of 35% to 48% and a saturated efficiency of 44% to 64% within the frequency band from 1.50 GHz to 2.35 GHz, which is about 44% fractional bandwidth.     

Analysis and design of a novel concurrent Class B/J continuum power amplifier

In this paper, a novel concurrent Class B/J continuum mode is presented based on waveform shaping of current and voltage. The behavior characteristics and performances of power amplifiers (PAs) in concurrent dual‐band mode are investigated in detail. According to the analysis of proposed concurrent mode, the optimal load impedances at fundamental, harmonic and intermodulation (IM) frequencies are related to the magnitude ratio of the two carriers. Comparing with concurrent Class‐B mode, two parameters α, β can be configured independently in the proposed concurrent mode, which provides more freedom and flexibility for design without output power and drain efficiency degradation. In order to verify the proposed theory, a 1.9/2.35 GHz dual‐band power amplifier based on proposed concurrent mode is designed, fabricated and measured. Experimental results show that when the PA is driven by two 10 MHz LTE signals concurrently with total 9.2 dB peak‐to‐average power ratio (PAPR), the total average power is 36.0 dBm with 40.6% drain efficiency, which indicates a good concurrent performance.     

Analysis and improvement of PSRR in an envelope‐tracking power amplifier using a common‐drain amplifier topology

A common‐drain power amplifier (PA) for envelope tracking systems is presented. In envelope tracking, the main PA operates mostly in compression and the power supply rejection ratio (PSRR) is not high. Furthermore, the output noise of the supply modulator can be mixed with the RF signal and generates out‐of‐band emissions. In this article, instead of using a common‐source topology, the PSRR of the envelope tracking PA is inherently improved by utilizing a common‐drain topology. A comprehensive analysis shows that the common‐drain topology is less sensitive to the supply noise, as compared to the conventional common‐source topology. The proposed common‐drain PA is implemented using a discrete LDMOS PD20010‐E RF transistor. Measurement results show that the PSRR of the proposed common‐drain PA is improved by up to 7 dB as compared to that of the common‐source PA. For a two‐tone input with 10 MHz bandwidth at the center frequency of 700 MHz, the power added efficiency (PAE) and IM3 of the envelope tracking common‐drain PA are 20% and ? 28 dBc, respectively, at an average output power of 33.4 dBm. The amplifier also shows a 12.4 dB power gain. Moreover, by utilizing the envelope tracking, the PAE is improved by more than 5%.