毫米波单片有源混频器的研制

采用OMMIC 0.18μm GaAs pHEMT工艺,研制了毫米波单片有源混频器.该混频器选用单栅极单端FET混频结构.在中频输出端设计了低通滤波器,以提高LO-IF、RF-IF的隔离度.芯片的尺寸仅为0.95mm×1.85mm.在射频频率为39GHz、输出中频频率为3GHz时,该混频器的变频增益为0.6dB,LO-IF隔离度大于55dB,RF-IF的隔离度大于30dB.     

一款集成驱动放大器的低变频损耗混频器设计

采用0.5μm GaAs工艺设计并制造了一款单片集成驱动放大器的低变频损耗混频器.电路主要包括混频部分、巴伦和驱动放大器3个模块.混频器的射频(RF)、本振(LO)频率为4～7 GHz,中频(IF)带宽为DC～2.5 GHz,芯片变频损耗小于7 dB,本振到射频隔离度大于35 dB,本振到中频隔离度大于27 dB.1 dB压缩点输入功率大于11 dBm,输入三阶交调点大于20 dBm.该混频器单片集成一款驱动放大器,解决了无源混频器要求大本振功率的问题,变频功能由串联二极管环实现,巴伦采用螺旋式结构,在实现超低变频损耗和良好隔离度的同时,保持了较小的芯片面积.整体芯片面积为1.1 mm×1.2 mm.     

120 GHz GaAs MMIC双平衡式基尔伯特混频器

作为低频段混频电路中的典型拓扑结构,基尔伯特单元在毫米波、太赫兹领域的应用较少,在Ⅲ-Ⅴ族化合物半导体单片微波集成电路(MMIC)设计中,超过100 GHz的基尔伯特混频器很少有文献报导。基于70 nm GaAs mHEMT工艺,设计了一款120 GHz的双平衡式基尔伯特混频器,同时对该混频器版图结构进行优化改进,提升了混频器中频差分输出端口间的平衡度。仿真结果显示该混频器在本振输入0 dBm功率时,在100~135 GHz频率范围内有(-7.6±1.5) dB的变频损耗,射频输入1 dB压缩点为0 dBm@120 GHz,中频输出带宽大于10 GHz,差分输出信号间的功率失配<1 dB,相位失配<4°。该芯片直流功耗为90 mW,面积为1.5 mm×1.5 mm。     

12GHz波段GaAs双栅MESFET单片混频器

研制了用于直播卫星接收机的12GHz波段GaAs双栅MESFET单片混频器。为了缩小芯片面积,把一个缓冲放大器直接与混频器的中频端口连接,而不采用中频匹配电路。混频器和缓冲放大器分开制造在两个芯片上,以便单独测量。混频器芯片尺寸为0.96×1.26mm~2,缓冲放大器芯片尺寸为0.96×0.60mm~2。混频器的双栅FET,以及缓冲放大器的单栅FET的电极间距很小。栅长和栅宽各1μm和320μm。在11.7～12.2GHz,带有缓冲放大器的混频器提供转换增益为2.9±0.4dB,单边带噪声系数12.3±0.3dB。本振(LO)频率为10.8GHz。低噪声变频器由单片前置放大器、镜象抑制滤波器,以及单片中频放大器与混频器连接构成。在同一频段,变频器提供转换增益为46.8±1.5dB,单边带噪声系数为2.8±0.2dB。     

12GHz频段GaAs双栅MESFET单片混频器

用于直播卫星接收机中的12GHz频段GaAs双栅MESFET单片混频器已经研制成功。为了减小芯片尺寸,缓冲放大器直接连在混频器的中频输出端后面,而不采用中频匹配电路。混频器和缓冲器制作在各自的芯片上,以便能分别测量。混频器芯片尺寸是0.96×12.6mm,缓冲器芯片尺寸是0.96×0.60mm。用于混频器的双栅FET和用于缓冲器的单栅FET都具有间隔紧密的电极结构。栅长和栅宽分别是1μm和320μm。带有缓冲放大器的混频器在11.7～12.2GHz射频频段提供2.9±0.4dB变频增益和12.3±0.3dB单边带(SSB)噪声系数。本振频率是10.8GHz。将一个单片前置放大器、一个镜象抑制滤波器和一个单片中频放大器与混频器连接起来构成低噪声变频器。变频器在上述频段内提供46.8±1.5dB的变频增益和2.8±0.2dB单边带噪声系数。     

基于GaAs肖特基二极管的330GHz接收前端技术研究

基于GaAs肖特基二极管,设计实现了310~330 GHz的接收机前端.接收机采用330 GHz分谐波混频器作为第一级电路,为降低混频器变频损耗,提高接收机灵敏度,分析讨论了反向并联混频二极管空气桥寄生电感和互感,采用去嵌入阻抗计算方法,提取了二极管的射频、本振和中频端口阻抗,实现了混频器的优化设计,提高了变频损耗仿真精度.接收机的165 GHz本振源由×6×2倍频链实现,其中六倍频采用商用有源器件,二倍频则采用GaAs肖特基二极管实现,其被反向串联安装于悬置线上,实现了偶次平衡式倍频,所设计的倍频链在165 GHz处输出约10 dBm的功率,用以驱动330 GHz接收前端混频器.接收机第二级电路采用中频低噪声放大器,以降低系统总的噪声系数.在310~330 GHz范围内,测得接收机噪声系数小于10.5 dB,在325 GHz处测得最小噪声系数为8.5 dB,系统增益为(31±1)dB.     

用于数字相控阵雷达收发组件的0.7~4.0GHz SOI CMOS有源下混频器

基于0.18μm SOI CMOS工艺设计了一款用于数字相控阵雷达的宽带有源下混频器。该混频器集成了射频、本振放大器、Gilbert混频电路、中频放大器以及ESD保护电路。该芯片可以直接差分输出,亦可经过片外balun合成单端信号后输出。射频和本振端口VSWR的测试结果在0.7~4.0GHz范围内均小于2,IF端口的VSWR测试结果在25 MHz~1GHz范围内小于2。当差分输出时,该混频器的功率转换增益为10dB,1dB压缩点输出功率为3.3dBm。电源电压为2.5V,静态电流为64mA,芯片面积仅为1.0mm×0.9mm。     

一种基于0.18-μm CMOS 工艺的超宽频带分布式无源栅注入混频器

本文介绍了一种基于0.18-μm CMOS 工艺的宽带无源分布式栅注入混频器。通过采用分布式拓扑结构,该混频器具有很宽的工作频带;中频输出端口使用了一个4阶低通滤波器,从而极大地提高端口之间的隔离度。此外,文中还分析了混频器的阻抗匹配与转换损耗。测试表明：该混频器在3GHz到40GHz频率范围工作时的转换损耗为 9.4 ~ 17 dB,零直流功耗,其芯片面积为0.78 mm2。在射频频率为23GHz固定中频频率为500MHz时的输入参考1dB压缩点大于4dBm。在整个工作频带内,其射频到本振端口、射频到中频端口及本振到中频端口的隔离度分别大于21dB, 38dB,45dB。该混频器适用于WLAN,UWB,Wi-Max,车载雷达系统和其它毫米波射频的相关应用。     

基于GaAs工艺的单片毫米波双平衡混频器设计

本文设计了一个用于高速无线通讯的26-40 GHz的单片双平衡混频器,提出了一种改进的Marchand balun用于扩展带宽。电路使用U型耦合线改善了端口之间的隔离度并提供了中频输出端口。该混频器使用0.15-µm GaAs PHEMT 工艺进行仿真并流片,测试结果与仿真结果具有较好的一致性,在26-40 GHz频带范围内,混频器具有较低的变频损耗为5.9-8.6 dB和较好的隔离度,并且中频带宽为DC-14 GHz。     

一款GaAs PHEMT超宽带无源双平衡混频器MMIC

混频器是微波系统关键部件之一.微波通信系统的宽带化和小型化发展趋势对混频器性能提出更高要求.基于GaAs赝配高电子迁移率晶体管(PHEMT)工艺设计了一款超宽带无源双平衡混频器单片微波集成电路(MMIC).该混频器采用环形肖特基二极管结构和两个新颖的螺旋式平行耦合微带线巴伦结构,大大提高了混频器工作带宽,减小了芯片尺寸,提高了本振(LO)到射频(RF)端口的隔离度.在片探针测试结果显示该芯片在上、下变频模式下RF和LO工作频率均为2～ 22 GHz,中频工作频率为0～4 GHz,变频损耗≤11.5 dB,LO到RF端口隔离度≥37 dB,LO输入功率为15 dBm.芯片尺寸为1.7 mm×1.0 mm.     

Millimeter-Wave Lange Coupler Design and Its Application in the Monolithic Image Rejection Mixer Design

This paper reports on the design of a Ka-band monolithic Lange coupler and its application in the monolithic fourth-harmonic image rejection mixer. Detailed design and analysis using Ansoft-HFSS simulator have been carried out. The simulated results of the Lange Coupler show the insert loss is better than ?3.64 dB; the amplitude balance is less than 0.55 dB and the phase balance is less than 0.65° from the 90° phase difference over the 30 to 40 GHz frequency range. The Lange Coupler is employed in a monolithic image rejection mixer that is fabricated by a commercial 0.18-μm pseudomorphic high electron-mobility transistor (pHEMT) process. The chip size is 1.4 mm × 1.9 mm. The image rejection ratio (IMR) is from 15 to 34 dB in the RF frequency range of 30 to 40 GHz.     

Ka频段GaAs单片平衡混频器

报道Ｋａ频段ＧａＡｓ单片平衡混频器的设计和研究结果。用自行开发的“ＴＵＭＭＩＸＥＲ”软件进行电路设计，工艺以半绝缘ＧａＡｓ为衬底，采用ＮｂＭｏ／ＧａＡｓ接触形成肖特基势垒二极管，以ＳｉＯ２和聚酰亚胺双介质为保护膜，增强了工艺的成功率。研制成功的芯片尺寸为：２ｍｍ×３ｍｍ×０．２ｍｍ，在ｆ＝３１～３６ＧＨＺ范围内ＮＦＳＳＢ≤１０ｄＢ，最佳点ｆ＝３２．２ＧＨｚＮＦ．ＳＳＢ＝８．７ｄＢ［ｆＩＦ＝１．２ＧＨｚ］。     

12GHz GaAs单片混频器

分析研究了一种新型１２ＧＨｚＧａＡｓＭＥＳＦＥＴ单片混频器，这种混频器采用级联ＦＥＴ作为混频元件。射频（ＲＦ）和本振（ＬＯ）信号分别通过各自的匹配网络进入混频电路，在中频输出端用中频缓冲放大器代替通常的中频匹配电路。电路在厚０．２ｍｍ，面积１．５ｍｍ×１．２ｍｍ的ＧａＡｓ基片上实现。设计的ＭＭＩＣ混频器在本振１１ＧＨｚ，射频１１．７～１２．２ＧＨＺ频率范围内的最大变频增益１．８ｄＢ。这一结果使进一步研究单片微波接收机成为可能。     

A Novel 94-GHz MHEMT Resistive Mixer Using a Micromachined Ring Coupler

In this letter, we present a high performance 94-GHz millimeter-wave monolithic integrated circuit resistive mixer using a 70-nm metamorphic high electron mobility transistor (MHEMT) and micromachined ring coupler. A novel three-dimensional structure of a resistive mixer was proposed in this work, and the ring coupler with the surface micromachined dielectric-supported air-gap microstrip line structure was used for high local oscillator/radio frequency (LO–RF) isolation. Also, the LO–RF isolation was optimized through the simulation. The fabricated mixer has excellent LO–RF isolation, greater than 29 dB, in 2-GHz bandwidth of 93–95GHz. The good conversion loss of 8.9dB was measured at 94GHz. To our knowledge, compared to previously reported W-band mixers, the proposed MHEMT-based resistive mixer using a micromachined ring coupler has shown superior LO–RF isolation and conversion loss.     

664GHz 接收前端技术研究

基于X 波段源,通过9×2×2 次倍频链实现了输出约1-2mW 的320-356GHz 全固态倍频源。该信号源作为本振信 号驱动664GHz 接收前端的二次谐波混频器,该混频器采用了有源偏置技术以降低混频器的本振驱动功率和接收机的噪 声温度。仿真结果表明,混频二极管在0.3mW 本振驱动功率及0.35V 直流偏置下,在650-680GHz 带宽内,仿真得到的 单边带变频损耗小于12dB,666GHz 最小损耗为10.8dB。     

Design of Ka-band Monolithic Image Rejection Mixer

In this paper, a 30–40 GHz monolithic image rejection mixer is described. The mixer employs two drain LO injection mixer cells, which can perform well even with zero drain bias voltage. Also it employs Lange Coupler for RF quadrature signal generation. The mixer is fabricated by a commercial 0.18-μm pseudomorphic high electron-mobility transistor (pHEMT) process. It achieves image rejection ratio of more than 20.4 dB and conversion loss of less than 12.6 dB in the frequency range of 30 to 38 GHz.     

A 31-GHz monolithic GaAs mixer/preamplifier circuit for receiver applications

The portion of a monolithic receiver containing integrated Schottky mixer diodes and MESFET'S with microstrip circuitry has been developed and tested at 31 GHz. This work is part of a program to establish the feasibility of monolithic receivers and transmitters at microwave and millimeter-wave frequencies. Receiver designs using high-cutoff frequency diodes in a mixer configuration followed by a MESFET amplifier are capable of operating from microwave through millimeter-wave frequencies. However, the fabrication of monolithic receiver designs requires the integration on the same wafer of devices with different material requirements. We have developed a compatible integration scheme which is fundamental to the fabrication of monolithic receivers at millimeter-wave frequencies. Fabrication and design considerations for the 31-GHz balanced mixer and IF preamplifier are described. Completed monolithic units typically exhibit a conversion gain of 4 dB from the signal frequency of 31 GHz to the IF frequency of 2 GHz. The associated noise figure is typically 11.5 dB.     

A D‐Band Balanced Subharmonically‐Pumped Resistive Mixer Based on 100‐nm mHEMT Technology

A D‐band subharmonically‐pumped resistive mixer has been designed, processed, and experimentally tested. The circuit is based on a 180° power divider structure consisting of a Lange coupler followed by a λ/4 transmission line (at local oscillator (LO) frequency). This monolithic microwave integrated circuit (MMIC) has been realized in coplanar waveguide technology by using an InAlAs/InGaAs‐based metamorphic high electron mobility transistor process with 100‐nm gate length. The MMIC achieves a measured conversion loss between 12.5 dB and 16 dB in the radio frequency bandwidth from 120 GHz to 150 GHz with 4‐dBm LO drive and an intermediate frequency of 100 MHz. The input 1‐dB compression point and IIP3 were simulated to be 2 dBm and 13 dBm, respectively.     

MMIC混频器电路设计与非线性分析

采用清华大学自行编制的混频器非线性分析程序ＴＵＭＩＸＥＲ，设计并研制了Ｋａ频段ＭＭＩＣ平衡混频器。在对混频器电路的大信号非线性仿真过程中，进行了多频谐波平衡分析，给出了混频器电路在多频输入情况下的输出频谱，对电路中的各种分布参数元件及微带不连续性区域，采用场匹配法作了严格计算。所研制的Ｋａ频段单片集成混频器电路，制作在一块２ｍｍ×３ｍｍ的ＧａＡｓ芯片上，在３１～３６ＧＨｚ频段上，混频器的噪声系数小于１０ｄＢ。     

Design and Implementation of a Millimeter Wave Monolithic Integrated Mixer

This paper discusses design and implementation of a millimeterwave monolithic integrated balanced mixer, the measured performance compared with the predicted one is also reported. By designing this MMIC mixer, various mathematical methods are used, in which the Method of Conversion Matrix has been extended by the author to meet the requirement of inter-modulation analysis. The mixer is realized in a 2×3mm ² GaAs chip, working in Ka band with bandwidth of 5GHz with a noise figure less than 10 dB.