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The Martingale Hardy Type Inequalities for Dyadic Derivative and Integral

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1465-1474页

作者： JianYingNIE Xing Guo Nie GUO Wei LOU Institute of Near Sensing technique with millimeter wave & Optical wave Nanjing University of Science ~ Technology Nanjing 210094 P. R. China

Since the Leibniz-Newton formula for derivatives cannot be used in local fields, it is important to investigate the new concept of derivatives in Walsh-analysis, or harmonic analysis on local fields. On the basis of idea of derivatives introduced by Butzer, Schipp and Wade, Weisz has proved that the maximal operators of the one-dimensional dyadic derivative and integral are bounded from the dyadic Hardy space Hp,q to Lp,q, of weak type （L1,L1）, and the corresponding maximal operators of the two-dimensional case are of weak type （Hi, L1）. In this paper, we show that these maximal operators are bounded both on the dyadic Hardy spaces Hp and the hybrid Hardy spaces H^#p 0〈p≤1.

关键词： martingale Hardy space dyadic derivative dyadic integral Walsh-Fejer kernels p-atom,quasi-local operator

Model and Simulation of a New Ultra-Narrow Trigger Frequency Alterable Pulse Generator

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Journal of Shanghai Jiaotong university(Science) 2011年第6期16卷 687-690页

作者：杨运峰曹振新叶展窦文斌苏宏艳 State Key laboratory of millimeter waves Southeast University National Key laboratory of millimeter wave System

Two new kinds of ultra-narrow trigger frequency alterable picosecond pulse generator are *** can produce positive pulses and the other can produce negative *** two pulse generators are subdivided into three parts:signal driving circuit,differentiator network and pulse shaping *** pulse shaping circuit is made of step recovery diode(SRD) and short-circuit microstrip line.A positive pulse with width of 54 ps(50%-50%),rising time of 30 ps(10%-90%) and falling time of 32 ps(90%-10%),and a negative pulse with width of 54 ps(50%-50%),rising time of 30 ps(90%-10%) and falling time of 30 ps(10%-90%) are achieved in *** of the components are ready-made and *** can be applied in ultra-wideband(UWB) communication system,such as transmitters and receivers.

关键词： pulse generator ultra-narrow step recovery diode(SRD) pulse shaping circuit

Display technique based on surface plasmon resonant effect

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Chinese Science Bulletin 2008年第15期53卷 2257-2264页

作者： CAO ZhenXin WU LeNan State millimeter wave Key laboratory Southeast University Nanjing 210096 China

In a surface plasmon resonant (SPR) configuration, real part in refraction coefficient of modulation layer material is monotonic with resonant wave length, while imaginary part is monotonic with resonant magnitude. Based on the fact above, a new type of display is proposed and designed. Firstly, a display pixel with either controllable color or controllable brightness is discussed, and then a display pixel with both controllable color and brightness is proposed in detail. At last, an SPR display with 8×8 pixels is developed and simulated. The results show that color and brightness of each display pixel in an SPR display can be tuned directly, with no need of synthesizing three basic colors, traditionally. Moreover, the display has many merits, such as high color resolution, high contrast, high brightness, fast re-sponse, etc. Yet practical usage of SPR display demands deeper study on properties of modulation layer material and fabrication techniques.

关键词： SPR效应自然色表面等离子共振仪分层材料

Large Signal Statistical Model Oriented Parameter Extraction Method for GaN High Electron Mobility Transistors

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Chinese Journal of Electronics 2017年第6期26卷 1319-1324页

作者： YU Xuming XU Yuehang WEN Zhang CHEN Zhikai HONG Wei State Key laboratory of millimeter wave Southeast Univeristy School of Electronic Engineering University of Electronic Science and Technology of China

Efficient parameter extraction method is essential to establish large signal statistical model. This paper presents an automatic parameter extraction method of I-V model for Gallium nitride(GaN) High electron mobility transistors(HEMTs) large signal statistical model. To accurate modeling the statistical characterization, all of 53 parameters in an I-V model are considered. In order to realize automatic parameter extraction, the model parameters are divided into blocks according to their physical meaning to reduce the complexity of the I-V model. Different parameter blocks are extracted separately by fitting the pulsed I-V transfer characteristic curves of the device at different quiescent bias points. A large signal statistical model for 0.25μm GaN HEMTs process has been established by using the proposed method after measuring 34 GaN HEMTs from 10 batches. The results show that the large-signal performances(Output power and Power added efficiency) can be reproduced with high accuracy by the proposed statistical model.

关键词： Statistical model Parameter extraction GaN HEMTs Large signal model

IMPLEMENTATION OF ANISOTROPIC PML FOR FREQUENCY DOMAIN FEM SOLUTION OF DISCONTINUITY IN DIELECTRIC waveGUIDE

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Journal of Electronics(China) 2001年第4期18卷 297-305页

作者： Qin Weiping Fang Dagang (millimeter wave technique laboratory, Nanjing University of Science & Technology, Nanjing 210094) millimeter wave technique laboratory Nanjing University of Science & Technology Nanjing

The anisotropic Perfectly Matched Layer(PML) absorbing boundary condition is implemented in a 2-D finite element formulation to solve dielectric waveguide discontinuity problems. The choice of parameters of anisotropic PML has been investigated. Using the boundary truncating technique, the solution process of Finite-Element Method (FEM) has been greatly simplified compared with other hybrid methods. The required computational resources have also significantly declined since the anisotropic PML interface can be placed much closer to the scatterer compared to other well known artificial boundary.

关键词： Anisotropic perfectly matched layer Dielectric waveguide discontinuity Finiteelement method

ALGEBRAIC MULTI-GRID METHOD IN TWO-DIMENSION ELECTRICALLY LARGE PROBLEMS

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Journal of Electronics(China) 2000年第1期17卷 77-83页

作者： Xu Yuan Fang Dagang (millimeter wave technique laboratory, Nanjing University of Science & Technology, Nanjing 210094) millimeter wave technique laboratory Nanjing University of Science & Technology Nanjing

In this paper the algebraic multi-grid principle is applied to the multilevel moment method, which makes the new multilevel method easier to implement and more adaptive to structure. Moreover, the error spectrum is analyzed, and the reason why conjugate gradient iteration is not a good relaxation scheme for multi-grid algorithm is explored. The numerical results show that our algebraic block Gauss Seidel multi-grid algorithm is very effective.

关键词： Moment method Algebraic multi-grid method Block Gauss Seidel algorithm

A High Power 320–356GHz Frequency Multipliers with Schottky Diodes

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Chinese Journal of Electronics 2016年第5期25卷 986-990页

作者： YAO Changfei ZHOU Ming LUO Yunsheng Science and Technology on Monolithic Integrated Circuits and Modules laboratory Nanjing Electronic Devices Institute(NEDI) Department of Microwave and millimeter wave Modules NEDI

A 320–356GHz fixed-tuned frequency doubler is realized with discrete Schottky diodes mounted on 50μm thick quartz substrate. Influence of circuit channel width and thermal dissipation of the diode junctions are discussed for high multiplying efficiency. The doubler circuit is flip-chip mounted on gold electroplated oxygenfree copper film for grounding of RF and DC signals, and better thermal transportation. The whole multiplying circuit is optimized and established in Computer simulation technology(CST) suite. The highest measured multiplying efficiency is 8.0% and its output power is 5.4mW at 328 GHz. The measured typical output power is 4.0mW in 320–356GHz.

关键词： Schottky diode Frequency doubler Efficiency Thermal dissipation

Comparison of on-wafer calibrations for THz In P-based PHEMTs applications

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Journal of Semiconductors 2015年第6期36卷 64-67页

作者：王志明黄辉胡志富赵卓彬王旭东罗晓斌刘军杨宋源吕昕 Beijing Key laboratory of millimeter wave and Terahertz Technology Beijing Institute of Technology National Institute of Metrology Hebei Semiconductor Research Institute

A quantitative comparison of multiline TRL （thru-reflect-line） and LRM （line-reflect-match） on-wafer calibrations for scattering parameters （S-parameters） measurement of InP-based PHEMTs is presented. The com- parison is undertaken for the first time and covers a frequency range from 70 kHz to 110 GHz. It is demonstrated that the accuracy of multiline TRL and LRM calibration is in good agreement. Both methods outperform the conven- tional SOLT calibration in the full frequency band up to 110 GHz. Then the excellent RF performance is obtained by extrapolation on the basis of inflection point, including a maximum current gain cut-off frequency ft of 247 GHz and a maximum oscillation frequency fmax of 392 GHz. The small-signal model based on LRM calibration is es- tablished as well. The S-parameters of the model are consistent with the measured from 1 to 110 GHz.

关键词： on-wafer calibration scattering parameters PHEMTs small-signal model

Design and implementation of 83-nm low noise InP-based InAlAs/InGaAs PHEMTs

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Journal of Semiconductors 2015年第8期36卷 83-87页

作者：王志明赵卓彬胡志富黄辉崔玉兴孙希国默江辉李亮付兴昌吕昕 Beijing Key laboratory of millimeter wave and Terahertz Technology Beijing Institute of Technology Hebei Semiconductor Research Institute National Institute of Metrology

83-nm T-shaped gate InP-based In0.52Al0.48As/In0.65Ga0.35As pseudomorphic high electron mobility transistors （PHEMTs） with excellent DC and RF performance as well as low noise characteristics are reported, including a maximum saturation current density/ass of 894 mA/mm, a maximum extrinsic transconductance gm, max of 1640 mS/mm, an extrapolated cutoff frequency ft of 247 GHz and a maximum oscillation frequency fmax of 392 GHz which were based on the measured S-parameters from 1 to 110 GHz. The minimum noise figure （NFmin） measured by the cold-source method is 1 dB at 30 GHz associated with a gain of 14.5 dB at Vds of 0.8 V and Ids of 17 mA. These results were obtained by the combination of increased InAs mole fraction in the channel, gate size scaling, parasitic reduction and the quantization channel. These excellent results make it one of the most suitable devices for millimeter wave （MMW） low noise applications.

关键词： InP PHEMT millimeter wave low noise on-wafer measurement