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1.
This article presents an accurate and efficient extraction procedure for microwave frequency small‐signal equivalent circuit parameters of AlInN/GaN metal‐oxide‐semiconductor high electron mobility transistor (MOSHEMT). The parameter extraction technique is based on the combination of conventional and optimization methods using the computer‐aided modeling approach. The S‐, Y‐, and Z‐ parameters of the model are extracted from extensive dynamic AC simulation of the proposed device. From the extracted Y‐ and Z‐ parameters the pad capacitances, parasitic inductances and resistances are extracted by operating the device at low and high frequency pinch‐off condition depending upon requirement. Then, the intrinsic elements are extracted quasi analytically by de‐embedding the extrinsic parameters. S‐parameter simulation of the developed small‐signal equivalent circuit model is carried out and is compared with TCAD device simulation results to validate the model. The gradient based optimization approach is used to optimize the small‐signal parameters to minimize the error between developed SSEC model and device simulation based s‐parameters. The microwave characteristics of optimized SSEC model is carried out (fT = 169 GHz and fmax = 182 GHz) and compared with experimental data available from literature to validate the model. 相似文献
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Lin‐Sheng Liu 《国际射频与微波计算机辅助工程杂志》2011,21(3):343-352
A complete empirical large‐signal model for the GaAs‐ and GaN‐based HEMTs is presented. Three generalized drain current I–V models characterized by the multi‐bias Pulsed I–V measurements are presented along with their dependence on temperature and quiescent bias state. The new I–V equations dedicated for different modeling cases are kept accurate enough to the higher‐order derivatives of drain‐current. Besides, an improved charge‐conservative gate charge Q–V formulation is proposed to extract and model the nonlinear gate capacitances. The composite nonlinear model is shown to accurately predict the S‐parameters, large‐signal power performances as well as the two‐tone intermodulation distortion products for various types of GaAs and GaN HEMTs. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE , 2011. 相似文献
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An improved method to determine the small‐signal equivalent circuit model for HEMTs is presented in this study, which is combination of the analytical approach and empirical optimization procedure. The parasitic inductances and resistances are extracted under pinch‐off condition. The initial intrinsic elements are determined by conventional analytical method. Advanced design system (agilent commercial circuit simulator) is used to optimize the whole model parameters with small deviation of initial values. An excellent agreement between measured and simulated S‐parameters is obtained for 2 × 20 μm2 gate width HEMT up to 40 GHz. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:464–469, 2014. 相似文献
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In this article, bias‐dependent small‐signal modeling approach based on neuro‐space mapping is proposed for MOSFET. Good agreement is obtained between the simulated and measured results for a 130 nm MOSFET in the frequency range of 100 MHz–40 GHz confirming the validity and effectiveness of our approach. In addition, higher accuracy is achieved by our approach in contrast to conventional empirical model. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
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Giovanni Crupi Alina Caddemi Dominique M. M.‐P. Schreurs Gilles Dambrine 《国际射频与微波计算机辅助工程杂志》2016,26(9):749-762
The small‐signal equivalent circuit modeling of microwave field‐effect transistors (FETs) is an evergreen and ever flourishing research field that has to be up‐to‐date with technological developments. Hence, modeling techniques must be continuously adapted and extended to suit best evolving technologies. The extraction of a FET high‐frequency small‐signal equivalent circuit is a very active and broad research area of significant interest, owing to its use as a prerequisite for noise and large‐signal modeling. The aim of this invited article is to provide in‐depth knowledge, critical understanding, and new insights into how to extract a FET small‐signal equivalent circuit from both theoretical and practical perspectives. To illustrate potential solutions to the key challenges faced by researchers, experimental results for different semiconductor technologies are reported and discussed. The study is focused on the hot research topic of the cold approach that has been, and still is, the most widely used technique for extracting FET small‐signal models and on the active role of the transconductance for successful modeling. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2016. 相似文献
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Anwar Jarndal 《国际射频与微波计算机辅助工程杂志》2019,29(9)
This article presents an artificial neural network (ANN) approaches for small‐ and large‐signal modeling of active devices. The small‐signal characteristics were modeled by S‐parameters based feedforward NN models. The models have been implemented to simulate the bias, frequency and temperature dependence of measured S‐parameters. Feedback NN based large‐signal model was developed and implemented to simulate the drain current and its inherent thermal effect due to self‐heating and ambient temperature. Both small‐ and large‐signal models have been validated by measurements for 100‐μm and 1‐mm GaN high electron mobility transistors and very good agreement was obtained. 相似文献
7.
The influence of guard‐ring (GR) on the direct current (DC) and high‐frequency performance of deep‐submicrometer metal oxide semiconductor field effect transistors (MOSFETs) is investigated in this study. MOSFETs with four different GRs are fabricated using 90 nm complementary metal oxide semiconductor (CMOS) process, and a detailed comparative study on their device performances is performed. A united DC and small signal equivalent circuit model that takes into the effect of GR is developed. A set of simple, but efficient formulas provide a bidirectional bridge for the S parameters transformation between devices with different GRs. The corresponding model parameters for MOSFETs with different GRs are determined from S parameter on‐wafer measurement up to 40 GHz. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:259–267, 2014. 相似文献
8.
Artem Popov Dmitry Bilevich Andrei Salnikov Igor Dobush Aleksandr Goryainov Alexey Kalentyev Aleksandr Metel 《国际射频与微波计算机辅助工程杂志》2020,30(9)
Based on the earlier experimental investigation of the existing GaAs pHEMT small‐signal modeling approaches and their applicability to different manufacturing processes, a combined automatic small‐signal noise model extraction technique, suitable for design of low‐noise and buffer amplifiers is proposed. The technique is based on the usage of measured S‐parameters of passive test structures and S‐parameters of the transistor in cold modes. Expressions are given for extraction of the intrinsic parameters of an equivalent circuit using linear regression. It is shown that the application of the proposed method allows extracting a small‐signal GaAs pHEMT model both in the probe‐tip reference planes and at on‐wafer calibration planes. The moving average algorithm was applied for preprocessing the results of measurements of the 50 Ohm noise figure during extraction of the noise model. The results of S‐parameters and noise figure simulation agree well with the measurements. The new technique was implemented as a plugin in a commercial EDA tool and enables to derive a ready‐to use small‐signal noise model from measured S‐parameters and 50 Ohm noise figure of a 0.15 μm GaAs pHEMT. 相似文献
9.
Giovanni Crupi Dominique M. M.‐P. Schreurs Alina Caddemi Antonio Raffo Giorgio Vannini 《国际射频与微波计算机辅助工程杂志》2010,20(1):87-93
The present article analyzes in detail different intrinsic small‐signal models for transistors. Particular attention is devoted to the non‐quasi‐static effects, which play a crucial role at microwave and millimeter‐wave frequencies. The advantages and disadvantages of these different equivalent circuit topologies are analyzed from both theoretical and experimental standpoints. This study clearly proves that best choice among these model representations depends on the specific device technology besides the investigated frequency range. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. 相似文献
10.
A new modeling methodology for gallium nitride (GaN) high‐electron‐mobility transistors (HEMTs) based on Bayesian inference theory, a core method of machine learning, is presented in this article. Gaussian distribution kernel functions are utilized for the Bayesian‐based modeling technique. A new small‐signal model of a GaN HEMT device is proposed based on combining a machine learning technique with a conventional equivalent circuit model topology. This new modeling approach takes advantage of machine learning methods while retaining the physical interpretation inherent in the equivalent circuit topology. The new small‐signal model is tested and validated in this article, and excellent agreement is obtained between the extracted model and the experimental data in the form of dc I–V curves and S‐parameters. This verification is carried out on an 8 × 125 μm GaN HEMT with a 0.25 μm gate feature size, over a wide range of operating conditions. The dc I–V curves from an artificial neural network (ANN) model are also provided and compared with the proposed new model, with the latter displaying a more accurate prediction benefiting, in particular, from the absence of overfitting that may be observed in the ANN‐derived I–V curves. 相似文献
11.
In this article, a large‐signal modeling approach based on the combination of equivalent circuit and neuro‐space mapping modeling techniques is proposed for MOSFET. In order to account for the dispersion effects, two neuro‐space (S) mapping based models are used to model the drain current at DC and RF conditions, respectively. Corresponding training process in our approach is also presented. Good agreement is obtained between the model and data of the DC, S parameter, and harmonic performance for a 0.13 μm channel length, 5 μm channel width per finger and 20 fingers MOSFET over a wide range of bias points, demonstrating the proposed model is valid for DC, small‐signal and nonlinear operation. Comparison of DC, S‐parameter, and harmonic performance between proposed model and empirical model further reveals the better accuracy of the proposed model. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE , 2011. 相似文献
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A framework for intelligent control is presented and different approaches to intelligent control are reviewed in light of this framework. The topics discussed include knowledge-based control, fuzzy control, neural networks, fault diagnosis, single loop control and distributed control. The key ideas behind these approaches are outlined and it is indicated how they may be used to make control systems with significantly improved capabilities. 相似文献
15.
This work aims at developing an explicit neuro‐fuzzy (NF) model to characterize complex engineered systems associated with high nonlinearity, uncertainties, and multivariable couplings. The NF model synergistically exploits the advantages of fuzzy belongingness of each input variable to all output variables and learning ability of neural networks. Owing to the inherent complexities associated with 2 complex engineered systems, a landfill and a boiler were selected to develop models that provide intelligent decisions for optimizing the operational parameters. Data compiled from field‐scale investigation/real plant operation involving various operating scenarios were used to develop the models. Predicting capability of the developed models was evaluated through the correlation coefficient and mean absolute percentage error values. Superiority of the proposed NF model to other similar models has been justified and demonstrated. 相似文献
16.
This article presents efficient parameters extraction procedure applied to GaN High electron mobility transistor (HEMT) on Si and SiC substrates. The method depends on combined technique of direct and optimization‐based to extract the elements of small‐signal equivalent circuit model (SSECM) for GaN‐on‐Si HEMT. The same model has been also applied to GaN‐on‐SiC substrate to evaluate the effect of the substrates on the model parameters. The quality of extraction was evaluated by means of S‐parameter fitting at pinch‐off and active bias conditions. 相似文献
17.
G. N. Marichal J. Toledo L. Acosta R. L. Marichal M. Sigut E. J. González 《Journal of Intelligent and Robotic Systems》2006,45(3):203-216
In this paper a new approach for steering a binocular head is presented. This approach is based on extracting the expert’s knowledge in order to improve the behaviour of the classical control strategies. This is carried out without inserting new elements in the system. Neuro–Fuzzy techniques have been chosen in order to reach this target. As a result a more friendly robotic system is achieved. 相似文献
18.
L. Acosta G. N. Marichal L. Moreno J. A. Méndez J. J. Rodrigo 《Journal of Intelligent and Robotic Systems》2000,27(4):305-319
In this paper, a neuro-fuzzy technique has been used to steer a mobile robot. The neuro-fuzzy approach provides a good way to capture the information given by a human. In this manner, it has been possible to obtain the rules and membership functions automatically whereas a fuzzy approach needs to make a prior definition of the rules and membership functions. In order to apply the neuro-fuzzy strategy, two mobile robots have been developed. However, in this paper only the smallest one has been considered. Similar results are obtained for the biggest one. The results of the approach are satisfactory, avoiding the obstacles when the mobile robot is steered to the target. 相似文献
19.
本文提出一种神经网络自组织控制器,并应用于非线性跟踪控制中,为了加快模糊控制器的在线学习,文中给出了一种变的最速梯度下降学习算法,仿真结果表明,该控制是有效的。 相似文献
20.
近年来,将神经网络用于图像融合处理取得了一些成果,但已有的方法存在着计算量大、需要用户设置网络结构和较多参数等缺点.自生成神经网络(SGNN)是一类自组织神经网络,它不需要用户指定网络结构和学习参数,而且不需要迭代学习,是一类特点突出的神经网络.提出一种基于SGNN进行图像融合的新方法,分3步：①对图像进行预处理,使用小波方法滤除图像的噪声;②用SGNN对图像像素进行聚类,将像素按灰度值聚为某几类;③对经过第2步处理的像素进行融合,用灰度值对像素进行模糊分类之后再用加权平均法精确化,最终得到融合图像.该方法易于使用、计算速度快.实验表明该方法融合结果的均方误差比拉普拉斯金字塔算法和小波变换方法降低约30%～60%. 相似文献