基于石英基片的二毫米频段三倍频器的研制

介绍了一个基于石英基片的二毫米频段三倍频器.采用反向并联变容二极管对结构实现倍频.建立了该二极管管对的等效电路模型并提取了模型参数.设计实现的倍频器输入为K型接头结构,输出为WR-8波导结构.获得的倍频器在输出频率为112.8～118.2 GHz范围内,输出功率大于0 dBm,最大输出功率超过2 dBm,最小倍频损耗为...     

D频段新型二倍频器设计

利用阻性二极管实现了一种D频段二倍频器,设计了一种新型双鳍线输入过渡结构,并成功应用于该二倍频器,该结构能更好地实现输入波导与二极管的匹配.该二倍频器采用肖特基势垒二极管MA4E2038,电路制作在0.05 mm厚石英基片上.仿真结果表明,在146.8 GHz处获得最高倍频效率10.3％.实物测试结果显示,在自偏置情况下倍频器在148 GHz处获得最高倍频效率2.3％,在0.7V偏置电压下倍频器在154 GHz处获得最大输出功率1.1 mW.输出功率可以满足多数应用下对信号源的需求,该倍频器对处于大气窗口的140GHz通信系统具有借鉴作用.     

毫米波宽带二倍频器设计

基于鳍线/悬置微带线耦合器提出了一种适用于毫米波变容二极管的宽带平衡式二倍频器结构。鳍线作为二极管对的驱动输入端,同时提供直流偏置接地。二极管对的直流偏置电压由输出悬置微带/WR-22波导转换的探针馈入。结合宽带输入WR-42波导/鳍线转换、宽带鳍线/悬置微带线耦合器以及宽带悬置微带线/WR-22波导转换实现了覆盖整个Q频段的平衡式二倍频器。在输入功率为+20dBm,变容管反偏置电压1.2V时,输出33～50GHz的范围内倍频效率大于10%。     

0.14 THz倍频器的设计与仿真

固态倍频器是毫米波及亚毫米波频段超外差接收机中的关键器件,其研制对太赫兹通信具有重要意义。介绍了一种基于肖特基变容二极管的宽带、高效率0.14 THz二倍频器的拓扑结构和仿真设计。该倍频器基于波导腔体石英基片微带电路形式,通过引线互联分别实现肖特基二极管接地和施加外部直流偏置,倍频器各部分采用了宽带电磁耦合结构设计。在开展了二极管建模及阻抗特性分析的基础上,采用三维有限元与非线性谐波平衡联合仿真方法,实现了倍频器的最优化设计。仿真结果表明,当输入频率为65 GHz~75 GHz,驱动功率为20 dBm时,倍频器的输出功率最高达10.1 dBm,倍频效率达10.8%。     

170 GHz高功率二倍频器设计及工艺优化

基于国产肖特基变容二极管,设计了一种170 GHz高功率二倍频器。为了提高肖特基二极管的散热效率,微带基板选用高热导率的氮化铝材料,基片粘接选用一种高热导率的导电银胶。通过实测数据可知,倍频器在171～189 GHz频段内的倍频效率大于10%。当输入功率为100～200 mW时,具有最大倍频效率20.5%;当输入功率为500～1 000 mW时,具有最大输出功率91 mW。     

基于肖特基变容二极管的0.17 THz 二倍频器研制

研制了一种基于肖特基变容二极管的0.17 THz 二倍频器, 该器件为0.34 THz 无线通信系统收发前端提供了低相噪、低杂散的本振信号.倍频器结构基于波导腔体石英基片微带电路实现, 其核心器件是多结正向并联的肖特基变容二极管.文中采用结参数模型和三维电磁模型相结合的方式对二极管进行建模, 通过两种电路匹配方式实现了0.17 THz 二倍频器的最优化设计, 最终完成器件的加工及测试.测试结果表明, 在输入80~86 GHz, 20 dBm 的驱动信号下, 倍频器的最大输出功率达12.21 mW, 倍频效率11%, 输出频点为163 GHz;当前端输入功率达到饱和状态时, 该频点输出功率可达21.41 mW.     

砷化镓倍频变容管的研制

倍频变容管的特性直接影响变容管倍频器的性能。文中介绍倍频变容管的设计 ,并制作出了与设计结果基本一致的器件。获得了输入 8GHz、5 0 0 m W,输出 16 GHz,最高倍频效率大于5 0 %的二倍频测试结果 ,并给出了 8mm四倍频器的使用结果     

W频段宽带倍频器

介绍了一个W频段宽带倍频器.采用反向并联二极管对结构实现宽带倍频.该倍频器输入为WR-28波导到微带过渡结构,输出为WR-10减高波导.在输入功率为5dBm时,在整个W频段输出功率为0.81±1.80dBm,二次谐波抑制度大于25dBc.该倍频器可把Ka频段的信号源扩展到W频段.     

140 GHz二倍频器的研制

太赫兹通信中本振链输出功率无法满足实际需求,因此提出一种基于肖特基变容二极管的宽带、高效率140 GHz 二倍频器设计方案。该倍频器结构基于波导腔体石英基片微带电路的混合集成方式实现。采用三维有限元与非线性谐波平衡联合仿真方法,实现了倍频器的最优化设计。根据仿真结果,完成了140 GHz二倍频器的加工、制作与测试工作。实测结果表明,在20 dBm的驱动功率下,倍频器的输出功率最高达6.6 mW,倍频效率7.15%;输入功率23 dBm对应的最大输出功率可达11.2 mW。该器件的成功研制使得实现太赫兹通信中的本振链成为可能。     

超宽带高效无源二倍频器设计

针对传统无源二倍频器倍频效率低,工作频带窄等问题,提出了一种基于肖特基二极管,利用悬置带线巴伦进行双平衡二倍频器输入输出匹配的方式实现宽带倍频的新方法,该方法在实现倍频器超宽带倍频的同时降低了倍频器的倍频损耗,微波软件仿真和实测结果表明,在输入信号频率1～11 GHz,输入信号功率8～12 dBm时,二倍频器倍频损耗小...     

一种新型双频宽负载整流电路

提出一种新型双频宽负载整流电路,它能有效回收环境中的微波电磁能量.该整流电路主要由阻抗压缩匹配网络、肖特基二极管和低通滤波器构成.其中,阻抗压缩匹配网络由一个L型阻抗调节器和一个Ⅱ型阻抗匹配器组成,该网络能够在200 ～ 4000Ω的负载区间内减小输入阻抗的变化范围,从而提高整流电路的匹配性能.ADS 2017软件仿真...     

Circuits for High-Efficiency Avalanche-Diode Oscillators

This paper describes and analyzes the circuits which have been used successfully for TRAPATT oscillator studies. The results lead to a better understanding of the TRAPATT oscillator and yield a simple model of the oscillator which is useful for circuit design. The circuit characteristics of an experimental TRAPATT oscillator are determined from measurements on the circuits and from equivalent circuit model calculations. The following conclusions can be drawn from the analysis. First, the avalanche diode requires sufficient capacitance near the diode to sustain the high-current state required for TRAPATT operation. Secondly, at a distance from the diode corresponding to approximately one half-wavelength at the TRAPATT frequency the transmission line containing the diode should be terminated by a low-pass filter. The function of the filter is to pass the TRAPATT frequency and to provide a shorting plane for the harmonics of that frequency. Finally, on the load side of the filter, tuning for the TRAPATT frequency is required. The model of the circuit described above suggests a simple explanation of the diode-circuit interaction in a TRAPATT oscillator. Simplified waveforms suggested by the model have been used to calculate power out-put, efficiency, dc voltage change, and RF impedance for the oscillator. The results agree within a few percent with those obtained for an experimental oscillator. An important conclusion of the analysis is that the high-efficiency operation of avalanche diodes at frequencies in the UHF range can be explained by the TRAPATT theory, even though the trapped-plasma or low-voltage state may last only 1/20th of the oscillation period.     

260 GHz GaN高功率三倍频器设计

基于GaN太赫兹二极管芯片,采用非平衡式电路结构,设计了一款260 GHz三倍频器。采用GaN肖特基二极管芯片提高电路的耐受功率和输出功率;采用“减高+减宽”的输出波导结构抑制二次谐波;采用高低阻抗带线结构设计了倍频器的输入滤波器和输出滤波器。测试结果显示,该三倍频器在261 GHz峰值频率下,实现最大输出功率为69.1 mW,转换效率为3.3%,同时具有较好的谐波抑制特性。     

基于石英基片的W波段高输出功率肖特基二极管倍频器

W-band quartz based high output power fix-tuned doublers are analyzed and designed with planar Schot- tky diodes. Full-wave analysis is carried out to find diode embedding impedances with a lumped port to model the nonlinear junction. Passive networks of the circuit, such as the low pass filter, the E-plane waveguide to strip transitions, input and output matching networks, and passive diode parts are analyzed by using electromagnetic simulators, and the different parts are then combined and optimized together. The exported S-parameters of the doubler circuit are used for multiply efficiency analysis. The highest measured output power is 29.5 mW at 80 GHz and higher than 15 mW in 76-94 GHz. The highest measured efficiency is 11.5% at 92.5 GHz, and the typical value is 6.0% in 70-100 GHz.     

Ka/Q band GaAs IMPATT amplifier technology

GaAs IMPATT diodes are capable of generating 2 to 3 W simultaneously with 18–22% efficiency in the 33 GHz to 46 GHz frequency band. The design of the amplifier circuits which utilize these devices is discussed. The circuit design is based on a 3-step closed form algorithm. The first step is a passive circuit characterization with an automatic network analyzer. In the second step, a computer is used to generate diode device lines. The third step is load line synthesis for predictable operation. The resulting performance is described. 2 W over a 2GHz bandwidth was achieved simultaneously with a minimum gain of 12 dB.     

Theoretical and experimental investigation of novel varactor-tunedswitchable microstrip ring resonator circuits

A microstrip ring resonator circuit loaded with two p-i-n diodes has been developed for use as a switchable filter. By replacing one p-i-n diode with a varactor diode, the switchable filter can be made electronically tunable. Isolation exceeding 20 dB with 9% tuning bandwidth was demonstrated. An analysis based on transmission line theory was used to model both circuits. The analysis includes the effects of diode parasitics, coupling gaps, dispersion, and mounting-gap capacitance. The experimental results agree very well with the theoretical calculation     

Single-stage electronic ballast with class-E rectifier as power-factor corrector

A single-stage high-power-factor electronic ballast with a Class-E rectifier as a power-factor corrector is proposed. A Class-E rectifier is inserted between the front-end bridge rectifier and the bulk filter capacitor to increase the conduction angle of the bridge-rectifier diode current for obtaining low line-current harmonics. The Class-E rectifier is driven by a high-frequency sinusoidal current source, which is obtained from the square-wave output voltage of the Class-D inverter through an LC series resonant circuit. A high-frequency transformer is used for impedance matching. The experimental results for a 32-W prototype ballast are given. The switching frequency was 61.3 kHz. At full power, the power factor was 0.992 and the total ballast efficiency was 88.3%. The lamp-current crest factor was about 1.36. The simulated and experimental results were in very good agreement.     

Compact Left-Handed Transmission Line as a Linear Phase–Voltage Modulator and Efficient Harmonic Generator

We construct a synthetic left-handed transmission line with cascaded varactors and shunt inductors. By modulating dc bias, the capacitance of the varactors can be changed and modulation of the output phase state is possible. For frequencies from 4.7 to 6.4 GHz, a very linear phase variation versus voltages of over 200deg phase variation with low insertion-loss variation (plusmn0.5dB) is demonstrated. This circuit can also act as an efficient harmonic generator when a large signal is applied. Since the left-handed transmission line shows high-pass filter response, harmonics generated are not seriously attenuated. However, because this synthetic transmission line is a very dispersive medium, strong dispersions and instabilities may arise. The circuit size is determined by the diode size and lumped-element inductor, allowing it to be compact     

Antiparallel operation of multiple high-efficiency avalanche diodes

This paper describes a new method for combining RF power from multiple high efficiency avalanche diodes. The basic circuit, called an antiparallel pair, has two avalanche diodes placed in opposite polarity to each other at the ends of an essentially one-half wavelength transmission line. A high-efficiency avalanche diode receives an incident half-sine wave and reflects an amplified half sine wave of opposite polarity. The half-sine wave travels back and forth along the transmission line with its polarity being reversed at each of the two diode positions. The antiparallel configuration has been extended to a circuit that combines RF power from four diodes. The four diodes are placed at the ends of a K-shaped microstrip line with two of the diodes being placed in opposite polarity with respect to the other two. The distance between any two diodes is approximately one-half wavelength. The K-shaped circuit has generated 620 W at 1.02 GHz.     

VHF／UHF宽带功率放大器设计

设计了一种30-520MHz功率放大器。采用传输线和集中常数相结合的阻抗匹配方式。实现了功率放大管的宽带匹配;对滤波器电子开关进行了分析并采用ADS进行仿真,插损及隔离度在全频段达到了设计要求;最后给出了测试结果,满足了指标的设计要求。该功率放大器已应用于某宽带通信设备且工作良好。