0.34 THz肖特基二极管高速OOK信号直接检波器

为了满足340 GHz高速OOK无线通信的需求,完成了340 GHz零偏置波导检波器的设计、加工和测试。首先,在高频电磁仿真软件HFSS中对准垂直结构二极管（QVD）进行建模仿真,并结合二极管的非线性模型确定二极管的阻抗;随后设计了输入波导-微带转换以及低通滤波器等无源结构,并同时对二极管进行阻抗匹配;最后进行了检波器的加工和测试。测试结果表明该检波器的电压灵敏度在334 GHz时最佳,最大值为2 210 V/W,并且在315 GHz~357 GHz频率范围内的典型值为1 400 V/W,其对应的等效噪声功率典型值为5 pW Hz-0.5。最后,还利用该检波器进行了340 GHz频段的高速OOK信号接收实验,结果表明,该检波器能够近乎无误地检测10 Gbps的OOK信号,并且在OOK信号速率为15 Gbps时,检波器解调得到的误码率为3.1510-7,证明了该检波器的高速信号检测能力能够满足高速OOK无线通信系统的需求。     

Millimeter-wave planar InP Schottky diodes and their small-signalequivalent circuit

Two planar indium phosphide Schottky diode designs have been fabricated and analyzed for millimeter-wave detector applications up to 150 GHz. Device structure and fabrication are discussed, and small-signal equivalent circuit models are presented. The following topics are included: the planar InP diode structure fabricated by megaelectron volt ion implantation. DC and RF measurements, circuit model values, and 94-GHz small-signal detector performance. The zero-bias detector sensitivity at 94 GHz was measured to be as high as 400 mV/mW, and the calculated tangential signal sensitivity was -56 dBm     

太赫兹平面肖特基二极管参数模型

根据太赫兹平面肖特基二极管物理结构,在理想二极管SPICE参数模型的基础上建立了二极管小信号等效电路模型。依据该二极管等效电路模型设计了基于共面波导（CPW）去嵌方法的二极管S参数在片测试结构,并对其在0.1~50 GHz、75~110 GHz频率范围内进行了高频小信号测试,利用测试结果提取了高频下二极管电路模型中各部分电容、电阻以及电感参数。将相应的高频下电容与电阻参数分别与低频经验公式电容值和直流I-V测试提取的电阻值进行了对比,并利用仿真手段对高频参数模型进行了验证。完整的参数模型以及测试手段相较于理想二极管SPICE模型和传统的参数提取方法可以更为准确地表征器件在高频下的工作状态。该建模思路可用于太赫兹频段非线性电路的优化设计。     

基于新颖宽带肖特基二极管模型的毫米波平衡式混频器设计

介绍了一个用于混频器设计的肖特基二极管模型.根据二极管的物理结构,建立了三维电磁模型,并采用有限元法分析该模型.根据二极管中分布的寄生效应,建立了直到110 GHz的宽带等效电路.基于该等效电路,设计并优化了一个Ka频段的平衡式混频器.在32～37 GHz频率范围内,测试的变频损耗为7.5～10 dB.测试结果与仿真结...     

5 THz混频二极管等效电路模型研究

采用电磁场和电路联合仿真,基于直流测试和三维电磁建模仿真技术,建立了截止频率5 THz的混频肖特基二极管的等效电路模型。重点研究了二极管的非线性结模型和外围结构三维电磁全波仿真模型,构建了考虑实际电路形式的四端口三维电磁全波仿真模型。该等效电路模型可用于太赫兹低频段混频模块设计,该模型的建立方法也为更高频段模型的建立提供了一种参考。基于该模型设计了一款220 GHz分谐波混频器,在192~230 GHz宽带范围内,双边带变频损耗小于10 dB,测试结果与仿真结果较为一致。     

Characteristics of an area-variable varactor diode

Photoresponses and microwave characteristics of an area-variable varactor diode are investigated in the frequency range of 1-7 GHz. The on/off ratio of the capacitance as large as 18.5 at 1 GHz is demonstrated and it is shown that the ratio strongly depends upon the access resistance between the cathode and the floating contacts. The capacitance of the diode is significantly altered by optical illuminations. The change increases nonlinearly with the input light power and the maximum value of 450% is achieved at 1 GHz with 1045 nW light power. These microwave and optical characteristics are described with a simple equivalent circuit model     

基于平面肖特基二极管的毫米波固定调节式谐波混频器

基于GaAs肖特基势垒二极管,研制出了两个不同波段的谐波混频器。在场仿真软件中,二极管的非线性结采用lumped端口来模拟,通过场分析方法分析二极管各端口的阻抗。谐波混频电路被分成不同部分来单独优化设计,基于优化设计的各独立电路,建立谐波混频器的整体场仿真模型,通过提取相应的S参数文件分析混频器的变频损耗。150GHz 谐波混频器测得最低变频损耗10.7dB,在135-165GHz变频损耗典型值为12.5dB。180GHz 谐波混频器测得最低变频损耗5.8dB,在165-200GHz变频损耗典型值为13.5dB,在210-240GHz变频损耗典型值为11.5dB。     

Integrated antenna with direct conversion circuitry for broad-band millimeter-wave communications

A compact integrated antenna with direct quadrature conversion circuitry for broad-band millimeter-wave communications is proposed. The conversion circuits include two even-harmonic mixers based on antiparallel diode pairs (APDPs). The equivalent circuit of the APDP derived here provides good agreement with the measured data from 17 to 23 GHz. Overall phase and amplitude imbalance between the in-phase/quadrature (I/Q) output channels are less than 1.2/spl deg/ and 1 dB at IFs of 10 and 100 MHz, respectively. An overall RF power conversion loss of 14.6 dB at the quadrature I/Q channels including the antenna is achieved in the frequency range from 39.75 to 40.25 GHz with a local oscillator (LO) power level of 11.8 dBm. LO leakages at 20 and 40 GHz are -31.5 and -44.8 dBm, respectively. In order to demonstrate the system capabilities for broad-band digital communication, a communication link is built with a pair of the proposed front-ends. Data transmission up to 1 Gb/s data rate for quadrature phase-shift keying modulation is demonstrated.     

Characterization of resonant tunneling diodes for microwave andmillimeter-wave detection

The authors report on the direct detection capabilities of resonant tunneling diodes in the 10-100 GHz range. An open circuit voltage sensitivity of 1750 mV/mW (in Ka-band) was measured. This is higher than the sensitivity of comparatively based commercially available solid-state detectors. The detector properties are a strong function of diode bias and the measured tangential signal sensitivity (-32 dBm at Ka-band with 1-MHz bandwidth) and the dynamic range (25 dB) of the diode are smaller compared to other solid-state detectors     

Broadband monolithic passive baluns and monolithic double-balancedmixer

The design and fabrication of four broadband monolithic passive baluns including CPW Marchand, multilayer MS Marchand, planar-transformer and broadside-coupled line baluns are presented. Operational frequencies range from 1.5 GHz to 24 GHz. Maximum relative bandwidths in excess of 3:1 are achieved. Simulated performances using full wave electromagnetic analysis are shown to agree with the measured results. Two accurate equivalent circuit models constructed from either electromagnetic simulated or measured S-parameters are developed for the MS Marchand and transformer baluns making the optimization of baluns and circuit design using the baluns much more efficient. The design of monolithic double-balanced diode mixer using two planar-transformer baluns is also presented. Without DC bias, the mixer shows a minimum conversion loss of 6 dB with the RF at 5 GHz and a LO drive of 15 dBm at 4 GHz. The measured input IP₃ of this mixer is better than 15 dBm over the 4 to 5.75 GHz frequency band     

On Estimating and Canceling Parasitic Capacitance in Submillimeter-Wave Planar Schottky Diodes

The equivalent circuit model of a submillimeter planar diode is investigated. In particular, the parasitic finger to pad capacitance that shunts the diode junction severely degrades the performance of frequency multiplier. Therefore, precise estimation of its value is crucial to circuit design in the submillimeter wave range. In this letter, a parallel diode structure is analyzed, and symmetry is utilized to remove parasitic elements external to the finger loop. This analytical approach is verified through measurement on a 200 GHz planar diode circuit. To increase the diode junction capacitance modulation ratio, one possible solution is also suggested.      

Schottky diodes for analogue phase shifters in GaAs MMICs

A simple Schottky diode structure, which is easily implemented in a foundry gallium arsenide (GaAs) process, is described. This structure occupies very much less area than the usual technique of realising Schottky diodes, using standard FET structures. Two variations of the diode have been characterized and modeled using a standard equivalent circuit. This has been used to design a simple analogue phase shifter based on a loaded-line configuration. The phase shifter was manufactured using a standard foundry process and has shown excellent results in terms of phase shift linearity with tuning voltage, combined with low insertion loss, over the range 2-8 GHz     

Millimeter-wave diode-grid phase shifters

Monolithic diode grids have been fabricated on 2-cm square gallium-arsenide wafers with 1600 Schottky-barrier varactor diodes. Shorted diodes are detected with a liquid-crystal technique, and the bad diodes are removed with an ultrasonic probe. A small-aperture reflectometer that uses wavefront division interference was developed to measure the reflection coefficient of the grids. A Phase shift of 70° with a 7-dB loss was obtained at 93 GHz when the bias on the diode grid was changed from -3 V to 1 V. A simple transmission-line grid model, together with the measured low-frequency parameters for the diodes, was shown to predict the measured performance over the entire capacitive bias range of the diodes, as well as over the complete reactive tuning range provided by a reflector behind the grid, and over a wide range of frequencies form 33 GHz to 141 GHz. This shows that the transmission-line model and the measured low-frequency diode parameters can be used to design an electronic beam-steering array and to predict its performance. An electronic beam-steering array made of a pair of grids using state-of-the-art diodes with 5-Ω series resistances would have a loss of 1.4 dB at 90 GHz     

高超噪比微波固态噪声源设计

固态噪声二极管的雪崩散弹噪声在一定条件下近似为白噪声。根据固态噪声二极管在雪崩击穿状态的等效电路,设计出与之匹配的电路结构,以实现超噪比的最大输出。在8.6~9.6 GH z,超噪比达到32~34 dB,平坦度±1 dB,超噪比随温度变化小于0.01 dB/°C。     

GaAs/AlAs resonant-tunneling diode for subharmonic mixers

A GaAs/AlAs resonant-tunneling diode is designed for use as part of a subharmonic mixer, and its prototypes are fabricated and characterized. Its current-voltage characteristics measured at room, liquid-nitrogen, or liquid-helium temperature provide evidence for its adequate performance over the entire temperature range. Its impedance is measured against frequency up to 40 GHz, on which basis an appropriate equivalent circuit is selected for the device, and its components are quantified. The operation of a subharmonic mixer incorporating the resonant-tunneling diode is simulated for a number of values of its quantum-well width. At liquid-helium temperature, adjusting the quantum-well width is predicted to make the appropriate local-oscillator power vary from 50 μW to 15 mW, while holding the conversion loss of a subharmonic mixer below 10 dB.     

Design of a W-band Frequency Tripler for Broadband Operation Based on a Modified Equivalent Circuit Model of GaAs Schottky Varistor Diode

This paper presents the design and experimental results of a W-band frequency tripler with commercially available planar Schottky varistor diodes DBES105a fabricated by UMS, Inc. The frequency tripler features the characteristics of tunerless, passive, low conversion loss, broadband and compact. Considering actual circuit structure, especially the effect of ambient channel around the diode at millimeter wavelength, a modified equivalent circuit model for the Schottky diode is developed. The accuracy of the magnitude and phase of S21 of the proposed equivalent circuit model is improved by this modification. Input and output embedding circuits are designed and optimized according to the corresponding embedding impedances of the modified circuit model of the diode. The circuit of the frequency tripler is fabricated on RT/Rogers 5880 substrate with thickness of 0.127 mm. Measured conversion loss of the frequency tripler is 14.5 dB with variation of ±1 dB across the 75?~?103 GHz band and 15.5?~?19 dB over the frequency range of 103?~?110 GHz when driven with an input power of 18 dBm. A recorded maximum output power of 6.8 dBm is achieved at 94 GHz at room temperature. The minimum harmonics suppression is greater than 12dBc over 75?~?110 GHz band.     

（英）一种基于透镜天线的宽带太赫兹准光检波器

设计了一种能够工作在140~325 GHz频带的宽带准光检波器,由一颗高阻硅透镜和单片集成检波芯片组成.设计并加工出双缝天线,在天线馈电端集成了肖特基二极管,该紧凑结构使其能够接收空间中的太赫兹辐射并转换为基带信号.为增强片上天线的方向性,利用MLFMM算法进行了扩展半球硅透镜的设计和优化,实现了良好的辐射特性.通过测试,天线在220 GHz和324 GHz处的辐射增益分别为26 dB和28 dB.在140~325 GHz,检波器测试得到的响应率可达到1 000~4 000 V/W,对应的等效噪声功率(NEP)估算为0.68~273 pW/Hz.     

高效170 GHz平衡式肖特基二极管倍频器

太赫兹源的输出功率是限制太赫兹技术远距离应用的重要参数。为了实现高效的太赫兹倍频器,基于高频特性下肖特基二极管的有源区电气模型建模方法,利用指标参数不同的两种肖特基二极管,研制出了两种170 GHz平衡式倍频器。所采用的肖特基二极管有源结区模型完善地考虑了二极管IV特性,载流子饱和速率限制,直流串联电阻以及趋肤效应等特性。通过对两种倍频器仿真结果进行对比,完备地分析了二极管主要指标参数对倍频器性能的影响。最后测试结果显示两种平衡式170 GHz倍频器在155~178 GHz工作带宽内的最高倍频效率分别大于11%和24%,最高输出功率分别大于15 mW和25 mW。从仿真和测试结果表示,采用的肖特基二极管建模方法和平衡式倍频器结构适用于研制高效的太赫兹倍频器。     

基于微带线的W波段二次分谐波混频器设计

采用微带混合集成电路技术设计了一款W波段二次分谐波混频器.通过分析二级管封装结构引入的寄生参量,提出了一种减小二级管并联寄生电容的方法.为了避免在W波段使用传统分谐波混频器中普遍使用的过孔接地及侧边平行耦合微带线带通滤波器,提出了一种改进型分谐波混频器结构.测试结果表明混频器在本振频率为45 GHz,中频频率为2.4 GHz时单边带变频损耗最小,最小值为8 dB.射频频率在90 ～ 100 GHz测试频率范围内,变频损耗的测量值小于10.5 dB.     

Low-noise 320?360 GHz cryogenically cooled waveguide Schottky diode mixer

Construction details and results of noise measurements on a cryogenically cooled Schottky diode mixer for the 320?360 GHz range are given. Critical mixer parts are electro-formed or machined on a precision lathe. The system double-sideband noise temperature is close to 400 K over a 30 GHz range with a lowest temperature of 385 K at 335 GHz. The mixer uses a tunable contacting backshort and has a total RF/IF double-sideband conversion loss of about 6dB, including input lens and diplexer losses. Corrected for input losses and second-stage contribution, a mixer double-sideband noise temperature of 271 K has been calculated at 335 GHz. This mixer has shown reliable and reproducible performance during five cooldowns to 15 K.