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A CMOS image-rejection mixer with 58-dB IRR for DTV receivers

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Journal of Semiconductors 2009年第6期30卷 94-99页

作者：袁帅李智群黄靖王志功 Institute of RF&OE Integrated Circuits Southeast University

The design,implementation,and characterization of an image-rejection double quadrature conversion mixer based on RC asymmetric polyphase filters（PPF） are presented.The mixer consists of three sets of PPFs and a mixer core for quadrature down conversion.Two sets of PPFs are used for the quadrature generation and the other one is used for the IF signal selection to reject the unwanted image band.Realized in 0.18-μm CMOS technology as a part of the DVB-T receiver chip,the mixer exhibits a high image rejection ratio（IRR） of 58 dB,a power consumption of 11 mW,and a 1-dB gain compression point of-15 dBm.

关键词： mixer image rejection polyphase filter

Design of a monolithic millimeter-wave doubly-balanced mixer in GaAs

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Journal of Semiconductors 2009年第8期30卷 119-122页

作者：徐雷钧王志功李芹 Institute of RF- & OE-ICs Southeast University School of Electrical and Information Engineering Jiangsu University

This paper presents the design of a 26-40 GHz monolithic doubly-balanced mixer for high-speed wireless communication. A modified Marchand balun is used to expand the bandwidth. A coupled line of the U section improves the port to port isolation and provides the IF-output port. The mixer was simulated and fabricated in 0.15-μm GaAs PHEMT technology;the measurement results agree well with the simulation results.The mixer achieves low conversion loss of 5.9 to 8.6 dB and high isolation over a 26-40 GHz RF/LO bandwidth and a DC-14 GHz IF bandwidth.

关键词： mixer MMIC millimeter-wave balun GaAs

Flow-Field of an Axisymmetric Lobed mixer

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Journal of Thermal Science 2004年第1期13卷 40-45页

作者： I.Yimer S.Manipurath I.Campbell W.E.Carscallen Gas Turbine Environmental Research Centre Aerodynamics LabInstitute for Aerospace ResearchNational Research Council Canada1200 Montreal RoadOttawaOntarioCanadaK1A 0R6Gas Turbine Environmental Research CentreAerodynamics LabInstitute for Aerospace ResearchNational Research Council Canada1200 Montreal RoadOttawaOntarioCanadaK1A 0R6Gas Turbine Environmental Research CentreAerodynamics LabInstitute for Aerospace ResearchNational Research Council Canada1200 Montreal RoadOttawaOntarioCanadaK1A 0R6Gas Turbine Environmental Research CentreAerodynamics LabInstitute for Aerospace ResearchNational Research Council Canada1200 Montreal RoadOttawaOntarioCanadaK1A 0R6

The flow-field of a fuel/air mixing system with an axisymmetric lobed mixer was numerically investigated. Large-scale streamwise vortices are formed immediately downstream of the mixer trailing edge, stretched further downstream, and finally broken into fragments where more intense mixing occurs. Both numerical and experimental results indicate that the length required for streamwise vortices breakdown in the confined flow-field of an axisymmetric lobed mixer is much shorter than that in the case of planar lobed mixers subject to parallel freestreams. For the conditions studied, the streamwise vortices start to breakdown at three wavelengths downstream of the mixer trailing edge.

关键词： axisymmetric lobed mixer confined flow fuel/air mixing.

Numerical study on solid suspension characteristics of a coaxial mixer in viscous systems

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2325-2336页

作者： Baoqing Liu Zilong Xu Qing Xiao Bolin Huang College of Energy Engineering Zhejiang UniversityHangzhou 310027China

A coaxial mixer consisting of an anchor and a Rushton turbine was selected as the research object,whose solid suspension characteristics were studied with the help of Computational Fluid Dynamics(CFD)method.Based on the Eulerian–Eulerian method and modified Brucato drag model,the just-suspension speed of impeller was predicted,and the simulation results were in good agreement with the experimental data.The quality of solid suspension under different rotation modes was also compared,and the results showed the coaxial mixer operating under co-rotation mode could get the best performance,and a larger anchor speed was beneficial to solid suspension by enhancing the turbulent intensity at the bottom.Compared with the anchor,the inner Rushton turbine played a dominant role in solid suspension due to its high rotational speed,whereas an extremely high inner impeller speed would make the uniformity of solid distributions become worse.Additionally,the effects of solid phase properties were also investigated,the results revealed that the higher the overall solid volume fraction and the smaller the Shields number,the worse the performance of solid suspension,meanwhile the solid suspension was more susceptible to solid density compared with particle diameter within the same Shields number gradient.

关键词： Coaxial mixer Mixing Two-phase flow CFD

Structural parameters improvement of an integrated HBT in a cascode configuration opto-electronic mixer

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Journal of Semiconductors 2013年第9期34卷 35-40页

作者： Hassan Kaatuzian Hadi Dehghan Nayeri Masoud Ataei Ashkan Zandi Photonics Research Laboratory(PRL) Electrical Engineering Department AmirKabir University of Technology

We analyze an integrated electrically pumped opto-electronic mixer, which consists of two InP/GalnAs hetero junction bipolar transistors （HBT）, in a cascode configuration. A new HBT with modified physical structure is proposed and simulated to improve the frequency characteristics of a cascode mixer. For the verification and calibrating software simulator, we compare the simulation results of a typical HBT, before modifying it and com paring it with empirical reported experiments. Then we examine the simulator on our modified proposed HBT to prove its wider frequency characteristics with better flatness and acceptable down conversion gain. Although the idea is examined in several GHz modulation, it may easily be extended to state of the art HBT cascode mixers in much higher frequency range.

关键词： cascode down conversion gain mixer opto-electronic photo HBT simulation

A low voltage low power up-conversion mixer for WSN application

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Journal of Semiconductors 2014年第4期35卷 123-127页

作者：吴晨健李智群孙戈 Institute of RF-& OE-ICs Southeast University Jiangsu Provincial Key Laboratory of Sensor Network Technology Soochow University

This paper presents an up-conversion mixer for 2.4-2.4835 GHz wireless sensor networks （WSN） in 0.18 μm RF CMOS technology. It was based on a double-balanced Gilbert cell type, with two Gilbert cells having quadrature modulation applied. Current-reuse and cross positive feedback techniques were applied in the mixer to boost conversion gain; the current source stage was removed from the mixer to improve linearity. Measured results exhibited that under a 1 V power supply, the conversion gain was 5 dB, the input referred 1 dB compression point was -11 dBm and the IIP3 was -0.75 dBm, while it only consumed 1.4 mW.

关键词： low voltage low power current-reuse positive feedback mixer

A high linearity dual-band mixer for IMT-A and UWB systems

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Journal of Semiconductors 2014年第11期35卷 130-134页

作者：唐旭升王晓羽杨江唐欣黄风义 RF & OEIC Research Institute National Mobile Communications Research LaboratorySoutheast University

The design and analysis of a reconfigurable dual-band down-conversion mixer for IMT-advanced （3.4 3.6 GHz） and UWB （4.2-4.8 GHz） applications are presented. Based on a folded double-balanced Gilbert cell, which is well known for its low voltage, simplicity and well balanced performance, the mixer adopts a capacitive cross-coupling technique for input matching and performance improvement. Switched capacitors and resistors are added to shift the working bands. Fabricated in a TSMC 0.13 #m process, the test results show flat conversion gains from 9.6 to 10.3 dB on the IMT-A band and from 9.7 to 10.4 dB on the UWB band, with a noise figure of about 15 dB on both bands. The input third-order intercept points （lIP3） are about 7,3 dBm on both of the frequency bands. The whole chip consumes 11 mW under 1.2 V supply and the total area of the layout is 0.76 × 0.65 mm^2.

关键词： mixer IMT advanced UW13 IIP3 conversion gain noise figure

A Broadband 630-720 GHz Schottky Based Sub-Harmonic mixer Using Intrinsic Resonances of Hammer-Head Filter

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China Communications 2019年第2期16卷 76-84页

作者： Yue He Yaoling Tian Li Miao Jun Jiang XianJin Deng Microsystem and Terahertz Research Center China Academy of Engineering Physics Institute of Electronic Engineering China Academy of Engineering Physics

An room temperature low noise anti-parallel Schottky diode based 630-720 GHz sub-harmonic mixer(SHM) is designed, built and measured. Intrinsic resonances in lowpass hammer-head filter have been adopted to prevent the LO and RF power leak from the IF channel, while greatly minimizing the transmission line size. The mixer consists of 15 um quartz terahertz circuit and 127 um Al2 O3 IF transformer circuit. An improved lumped element equivalent noise model of SBDs guarantees the accuracy of simulation. The measurement indicates that with local oscillating(LO)signal of 2-8 mW, the lowest double sideband(DSB) conversion loss is 8.2 dB at 645 GHz,and the best DSB noise temperature is 2800 K at 657 GHz. The 3 dB bandwidth of conversion loss is 75 GHz from 638 to 715 GHz. The work IF frequency band is above 20 GHz ranging from 1 to 20 GHz with-10 dB return loss.

关键词： erahertz sub-harmonic mixer hammer-head filter Schottky diode

A 0.18μm CMOS Gilbert low noise mixer with noise cancellation

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Journal of Semiconductors 2012年第2期33卷 77-81页

作者：孙景业黄鲁袁海泉林福江 Department of Electronic Science and Technology University of Science and Technology of ChinaHefei 230027China

This paper presents a broadband Gilbert low noise mixer implemented with noise cancellation technique operating between 10 MHz and 0.9 GHz.The Gilbert mixer is known for its perfect port isolation and bad noise performance.The noise cancellation technique of LNA can be applied here to have a better NF.The chip is implemented in SMIC 0.18μm CMOS technology.Measurement shows that the proposed low noise mixer has a 13.7-19.5 dB voltage gain from 10 MHz to 0.9 GHz,an average noise figure of 5 dB and a minimum value of 4.3 dB.The core area is 0.6 x 0.45 mm;.

关键词： noise cancellation mixer LNA low noise figure