基于倒扣技术的K波段 CPW环形混频器

本文给出了一种应用在汽车防撞雷达前端的单平衡环形混频器。混频器设计中采用CPW线作为传输线,以降低传输损耗,并提出了一种新的混合环的分析方法。电路设计中重点考虑了在较低的本振功率的情况下获得较小的变频损耗。当本振在25GHz有9dBm的信号功率输入时,混频器有5. 2dB的变频损耗,本振到射频和本振到中频分别有46. 4dB和37. 7dB的隔离度。该混频器的结构简单,便于批量生产。     

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.     

GaAs MMIC宽带双平衡混频器的研制

采用GaAs肖特基二极管工艺,设计并制造了一款宽带无源双平衡混频器,射频、本振频率为1.5～3.7 GHz,变频损耗小于10 dB,本振到射频隔离度大于35 dB,中频带宽DC～0.8 GHz.该混频器采用了环形二极管和螺旋式巴伦结构,在获得良好的变频损耗与隔离度的同时,显著减小了芯片面积,整体芯片尺寸为1.2 mm × 1.2 mm.     

基于LTCC技术的C频段星载接收机混频器

利用低温共烧陶瓷(LowTemperature Co-fired Ceramic,简称LTCC)技术,设计制作了一种可应用于C频段星载接收机的双平衡混频器。该混频器将射频和本振巴伦等无源器件集成在多层LTCC基板内,实现了电路的小型化、高集成度和高可靠性。测试表明,当射频输入为5.925～6.425GHz、本振频率为2.225GHz、中频输出频率为3.7～4.2GHz时,混频器的变频损耗≤9.3dB,P1dB为5.7dBm,本振到射频和本振到中频的隔离度分别为39.44dB和35.58dB。混频器的尺寸为40×22×1.92mm3。     

X波段低变频损耗混频器设计

采用商用肖特基势垒二极管HSMS-2822,研制了低变频损耗、高隔离度X波段单平衡混频器。为实现所需要的混频带宽,本振信号和射频信号采用三分支定向耦合器耦合输入,仿真研究表明其能有效地改善工作频率带宽,提高本振端口与射频端口间的隔离度。通过设计合理的空闲频率回收电路,回收利用空闲频率能量,能有效地降低混频器变频损耗,提高本振信号、射频信号及空闲频率信号到中频端口的隔离度。在10.6GHz,测得最小变频损耗5.67dB;在10～11.5GHz,混频器变频损耗为6.4±0.7dB,变频损耗平坦度好,RF-IF隔离度优于27dB,LO-IF隔离度高于24dB,LO-RF隔离度优于14dB。     

太赫兹宽带分谐波混频器设计

太赫兹分谐波混频器的变频损耗、噪声系数等指标与基波混频器相近,且本振频率为射频频率的一半,大大 降低了本振源的设计难度和制作成本,是高性能太赫兹接收前端的关键部件。本文介绍了一种覆盖全波导带宽的太赫 兹宽带分谐波混频器的设计,对电路中射频波导至悬置带线过渡结构和本振中频双工器进行仿真和优化设计。并以 0.14~0.22THz 分谐波混频器为例进行设计和制作,测试结果表明0.14 ~0.22THz 分谐波混频器在全波导频段内最大变频 损耗低于15dB,中频3dB 带宽大于20GHz。     

采用次谐波混频技术的毫米波超宽带混频器研制

提出了一种次谐波混频技术结合宽带匹配滤波电路的设计方法,能有效降低本振源的制作难度,并可扩展中频带宽。应用高频场仿真软件以及谐波平衡仿真软件,研制了两个频段的超宽带次谐波混频器。测试结果:K频段混频器,固定本振频率15 GHz,射频频率在18~26.5 GHz的频带内变化时,变频损耗小于10.7 dB,最小变频损耗为7.5 dB;Ka频段混频器,固定本振频率22 GHz,射频频率在26.5~40 GHz的频带内变化时,变频损耗小于11.5 dB,最小变频损耗为8 dB。测试结果指标与传统的双平衡混频器指标相当,证明了电路设计方案的正确性。     

一种U 波段鳍线单平衡混频器的设计

本文介绍了一种U 波段鳍线单平衡混频器的设计过程并给出了测试结果。混频器使用M/A-COM 公司的肖特基势垒二极管MA4E2037,整个电路制作在一块厚度为0.127mm 的RT-Duroid 5880 软基片上。射频端口采用鳍线过渡,本振端口通过波导-微带探针过渡,中频通过SMA 接头输出。测试结果显示,鳍线悬置微带线结构的混频器在本振为42 GHz, 射频在40～60GHz 范围内变化时,其变频损耗小于8.71 dB,本振到射频的隔离度大于25dB。     

0.67 THz宽带谐波混频器设计

为研制太赫兹多频段高灵敏度探测仪,依靠太赫兹砷化镓平面肖特基二极管的非线性特性,结合石英薄膜工艺,设计了宽带0.67 THz谐波混频器,并分析了砷化镓平面肖特基二极管性能表征参数指标对太赫兹混频器性能的影响。0.67 THz谐波混频器采用整体综合的设计方法,结合电气仿真软件ADS和电磁仿真软件HFSS,优化电路中不连续性微带与波导之间的电磁空间耦合效率,以混频器的变频损耗为优化目标,最终实现0.67 THz谐波混频器仿真设计。0.62~ 0.72 THz射频范围内,混频器单边带最低变频损耗小于8 dB,本振功率小于4 mW,本振端口与中频端口、射频端口与中频端口之间隔离度大于-30 dB。     

基于肖特基二极管的450 GHz二次谐波混频器

为了在亚毫米波波段进行遥感探测,研制了450GHz的二次谐波混频器.混频器的核心部件是一对反向并联的肖特基二极管,长度为74μm,截止频率高达8THz.在石英基片上搭建悬置微带的匹配电路,并采用一分为二的金属腔体.在二极管的仿真中获得二极管管芯的输入阻抗,然后考虑二极管的封装、匹配电路,仿真得到混频器的单边带变频损耗为8.0dB,所需本振功率为4mW.测试表明,本混频器的单边带变频损耗的最佳值为14.0dB,433~451GHz之间的损耗小于17.0dB,3dB带宽为18GHz,所需的本振功率为5mW.     

Broadband single- and double-balanced resistive HEMT monolithicmixers

A double-balanced (DB) 3-18 GHz and a single-balanced (SB) 2-16 GHz resistive HEMT monolithic mixer have been successfully developed. The DB mixer consists of a AlGaAs/InGaAs HEMT quad, an active LO balun, and two passive baluns for RF and IF. At 16 dBm LO power, this mixer achieves the conversion losses of 7.5-9 dB for 4-13 GHz RF and 7.5-11 dB for 3-18 GHz RF. The SB mixer consists of a pair of AlGaAs/InGaAs HEMT's, an active LO balun, a passive IF balun and a passive RF power divider. At 16 dBm LO power, this mixer achieves the conversion losses of 8-10 dB for 4-15 GHz RF and 8-11 dB for 2-16 GHz RF. The simulated conversion losses of both mixers are very much in agreement with the measured results. Also, the DB mixer achieves a third-order input intercept (IP₃) of +19.5 to +27.5 dBm for a 7-18 GHz RF and 1 GHz IF at a LO drive of 16 dBm while the SB mixer achieves an input IP ₃ of +20 to +28.5 dBm for 2 to 16 GHz RF and 1 GHz IF at a 16 dBm LO power. The bandwidth of the RF and LO frequencies are approximately 6:1 for the DB mixer and 8:1 for the SB mixer. The DB mixer of this work is believed to be the first reported DB resistive HEMT MMIC mixer covering such a broad bandwidth     

InAlAs/InGaAs HBT X-band double-balanced upconverter

We report on an InAlAs/InGaAs HBT Gilbert cell double-balanced mixer which upconverts a 3 GHz IF signal to an RF frequency of 5-12 GHz. The mixer cell achieves a conversion loss of between 0.8 dB and 2.6 dB from 5 to 12 GHz. The LO-RF and IF-RF isolations are better than 30 dB at an LO drive of +5 dBm across the RF band. A pre-distortion circuit is used to increase the linear input power range of the LO port to above +5 dBm. Discrete amplifiers designed for the IF and RF frequency ports make up the complete upconverter architecture which achieves a conversion gain of 40 dB for an RF output bandwidth of 10 GHz. The upconverter chip set fabricated with InAlAs/InGaAs HBT's demonstrates the widest gain-bandwidth performance of a Gilbert cell based upconverter compared to previous GaAs and InP HBT or Si-bipolar IC's     

26.5–30-GHz Resistive Mixer in 90-nm VLSI SOI CMOS Technology With High Linearity for WLAN

A resistive mixer with high linearity for wireless local area networks is presented in this paper. The fully integrated circuit is fabricated with a 90-nm very large scale integration silicon-on-insulator (SOI) CMOS technology and has a very compact size of 0.38 mm$, times,$0.32 mm. Design guidelines are given to optimize the circuit performance. Analytical calculations and simulations with an SOI large-signal Berkeley simulation model show good agreement with measurements. At an RF of 27 GHz, an IF of 2.5 GHz and zero dc power consumption, a conversion loss of 9.7 dB, a single-sideband noise figure of 11.4 dB, and a high third-order intercept point at the input of 20 dBm are measured at a local-oscillator (LO) power of 10 dBm. At lower LO power of 0-dBm LO power, the loss is 10.3 dB. To the knowledge of the author, the circuit has by far the highest operation frequency reported to date for a resistive CMOS mixer. Furthermore, it provides the highest linearity for a CMOS mixer operating at such high frequencies.     

60 GHz MMIC double balanced Gilbert mixer in mHEMT technology with integrated RF, LO and IF baluns

A 60 GHz MMIC double balanced Gilbert mixer (DBGM) with integrated RF, LO and IF baluns has been designed, fabricated in an mHEMT MMIC technology and characterised with probed measurements. Although a standard mixer topology for integrated circuits in the low gigahertz region, the DBGM has had very little impact in the millimetre-wave range. To the authors' knowledge, the presented DBGM operates at the highest RF frequency ever published for any FET-based Gilbert type mixer, double or single balanced. A measured down conversion gain of 1.5 dB at 60 GHz is obtained with a DC power consumption of 300 mW. Further, IF bandwidth, isolation between the LO, RF and IF ports, 1 dB compression point for the RF input, and LO input power is presented     

Practical performance of a microwave distributed MESFET mixer

The practical performance of a two-stage microwave distributed MESFET mixer is presented for the first time, based on the concept of distributed or travelling-wave mixing. A conversion loss of 4 dB (+1, ?0.5 dB) was measured at fixed bias with a signal frequency varying from 2 to 10 GHz for an IF of 1.5 GHz and 6 dBm of LO pump power. This performance is believed to be superior to any currently available microwave mixer covering this wide bandwidth.     

Low-noise Ku-band MMIC balanced P-HEMT upconverter

An enhanced design methodology for a low-noise Ku-band monolithic balanced high electron mobility transistor (HEMT) upconverter and its performance are presented in this paper. The mixer topology consists of a common source/common gate HEMT pair that performs the mixing and balun functions. A detailed study has been done to establish the role of the transistor model elements in the performance of the mixer. Based on this study, a new analysis is proposed to optimize the operating point of the mixer in order to get a tradeoff between conversion gain and port isolations. To combine the LO and intermediate-frequency (IF) signals, active circuits were used, as well as a high-pass filter in order to improve the isolations. The circuit size, including the filter and the combiners, is 3 mm². On-wafer measurements show a conversion gain over 2.5 dB, with only 3 dBm of LO power. A LO/RF isolation over 27 dB was measured in the whole LO band. The LO/IF isolation is over 27 dB thanks to the low reverse gain of the combiner HEMT's. A single sideband noise figure of 7.3 dB has been obtained     

A 9–31-GHz Subharmonic Passive Mixer in 90-nm CMOS Technology

A subharmonic down-conversion passive mixer is designed and fabricated in a 90-nm CMOS technology. It utilizes a single active device and operates in the LO source-pumped mode, i.e., the LO signal is applied to the source and the RF signal to the gate. When driven by an LO signal whose frequency is only half of the fundamental mixer, the mixer exhibits a conversion loss as low as 8–11 dB over a wide RF frequency range of 9–31GHz. This performance is superior to the mixer operating in the gate-pumped mode where the mixer shows a conversion loss of 12–15dB over an RF frequency range of 6.5–20 GHz. Moreover, this mixer can also operate with an LO signal whose frequency is only 1/3 of the fundamental one, and achieves a conversion loss of 12–15dB within an RF frequency range of 12–33 GHz. The IF signal is always extracted from the drain via a low-pass filter which supports an IF frequency range from DC to 2 GHz. These results, for the first time, demonstrate the feasibility of implementation of high-frequency wideband subharmonic passive mixers in a low-cost CMOS technology.