| With the development of MMIC processing,Millimeter wave is becoming more and more practicable among secured communication,microwave imaging,precise missile guidance,point-to-point communication,driving assistance radar,etc.due to its inherent wide bandwidth and high resolution.Lately,requirements for big data,AI,and Internet of Things are driving humanity to process huge amount of information faster and with high mobility.The capacity of current 3G and 4G mobile communication system is becoming a bottle neck.However,the spectrum resource in lower frequency band is almost fully deployed.Mobile communication system has to advance to higher frequencies.As a result,5G in millimeter wave range is a hot topic for industries and academic research.5G communication system employs higher bandwidth and higher order modulation schemes,which puts higher requirements on system performance,such as linearity and EVM.However,the millimeter circuits face a lot of challenges.As the wavelength reaches millimeter or sub-millimeter range,traditional circuit design method is no longer valid.Due to physical limitations,performances of MMICs such as noise figure,linearity,phase noise,power efficiency will drastically deteriorate at such high frequencies,making the design and application of millimeter wave communication circuits more difficult.Although millimeter MMICs are widely used in radar and remote-sensing area,the design methodologies covering linearity,EVM,power efficiency for communication systems are not well developed.In addition,traditional equivalent-circuit device models become less and less accurate.As a result,both design methodology and device models need to be improved for higher frequencies.In this paper,new device modeling and parameter extraction methods are discussed by studying the new behaviors of devices under millimeter wave range.A number of new design theories and methods for different functional blocks are introduced in this thesis work.With the help of above items,MMICs of LNA,PA,Mixer,Multiplier and VCO for 5G communications are designed,fabricated and verified.This thesis work contains the following aspects:Firstly,in order to improve the design accuracy and reduce design iterations,modeling and parameter extraction method of millimeter and sub-millimeter device have been studied here.Distributed effects and parasitic effects at high frequency are analyzed first.And then modeling error is estimated via the studying of several high frequency effects such as self-heating effect,DC-AC dispersive effects,distribution effect and boundary condition calibration techniques for EM simulation.A new accurate small-signal model with freely scaling the gate width and number of gates is proposed,which provides a solid foundation for the further circuits design.Secondly,the co-design of high efficiency and high linearity of millimeter wave power amplifier is discussed here.Key technologies of harmonic suppression technic,low-loss matching network,dynamic biasing and “Sweet-Spot” for high-efficiency PAs are discussed.Specially,the trade-off design and relationship between harmonic suppression and linearization technics are explored.In the meantime,problems such as odd-mode oscillation,spurious and gate current design are also analyzed.Finally,a compromise design between linearity and efficiency performance is achieved by combining "Sweet-Spot" and harmonic control.A Ka-band balanced PA and a W-band high power PA are designed and fabricated to verify the design methodology,solving the key development problems of millimeter transmitter.Thirdly,low phase noise millimeter wave VCO design method is analyzed.Different structures for millimeter wave VCO are compared,and the major source of phase noise and the key design points are analyzed.The conditions of oscillatory and stability in circuits design are analyzed by the negative resistance oscillation.The design of optimization bias choice and the important role of cross-phase lock loop technics are summarized at the same time.Two kinds of Ka-band and W-band VCO MMICs are designed and fabricated,exploring the accurate signal source in high-frequency communication systems.Also,in order to improve the linearity and phase noise in millimeter wave mixer and frequency multiplier,the source of phase noise and non-linearity are summarized.The mechanism and improved method of the imbalance of quadrature hybrid and Baluns are proposed.Also,the design process of passive mixer is summarized here.At the same time,the analysis of limit factors for bandwidth and performance in mixer design utilizing the nonlinear diode model and high performance mixer diode technology,the relationship between diode saturation characteristic and image rejection ratio of IQ mixer,the mechanism and source of intermodulation signal in mixer,and the high-linearity design of mixer are analyzed separately.Finally,referring to these theories,several types of mixers are designed and fabricated,including a Ka-band double-balanced stacked mixer,a W-band single-balanced mixer,a C-band wideband IQ mixer and a V-band IQ mixer.In the meantime,millimeter multiplier design technics are analyzed.Pros and cons of different circuit topologies,and the key design technics of Class-E,balanced,Class-F multiplier are summarized.Also,the key design technics of frequency multiplier and buffer amplifier are discussed.A Ka band high-rejection active 4x multiplier is designed and fabricated finally,which achieves a complete millimeter wave frequency conversion solution.Finally,a kind of method of low noise amplifier design in millimeter wave has been proposed to improve the design accuracy.Begin with the device noise performance and different noise models,together with the classical two-port noise theory,parasitic and distributed effects of different gate width and number of gates,and the relationship between noise figure and device bias are studied.A LNA design method which can be quantized accurately is proposed,the precise quantification basis of optimum single finger gate width and gate index,optimum bias operating point and optimum negative feedback inductance are obtained.At the same time,the design flow of LNA for broadband and narrowband requirements is proposed based on theoretical analysis.The design method by quantifying the noise performance precisely is proposed finally and lays the foundation of millimeter front-end MMICs,of which correctness is verified by designing a W-band LNA based on that.Design methodologies and theories for severial typical MMICs are detailed analyzed in this thesis work.These methodologies and theories are of good academic and engineering value.All the MMICs are fabricated and analyzed based on NEDI compound semiconductor platform.Numbers of these MMICs are widely deployed in communication systems,contributing to the localization of critical devices in millimeter wave radar and communication systems and the exploration of impendent research on millimeter wave MMICs.This thesis work has the following innovative achievements(1)A new distributed and precise device model extraction technique which can be accurately scaled for the millimeter devices is presented.The source of error in the millimeter device model extraction is analyzed.Through the analysis of high-frequency distribution effect,DC-AC dispersive effects,and the precision of Anglov,EEHEMT as well as TOM4 device model extraction method,a method of passive calibration structure design and feasible error correction for EM simulation is proposed,With the help of the presented device model,5 W Ga N PA MMIC working in the 3mm-band is designed and fabricated.The performance has reached the international advanced level.(2)A Ka-band balanced PA MMIC with medium-power level is designed and fabricated with the combination of the class-F biasing and “Sweet-Spot” design method.This Ka-band PA MMIC has high PAE,high linearity performance and shows insensitivity for the load impedance change,which has been applied in the military and civilian electronics successfully.(3)A global optimization design method for millimeter LNA MMIC is proposed based on the analyzation and designation of several parameters such as the minimized noise factor,noise resistance and device size,avoiding the randomness in the experiential design.A W-band balanced LNA MMIC is designed and fabricated.Good noise factor performance is shown in the measured results. |
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