Artificial-line-division distributed ICs with 0.1-μm-gate-length GaAs MESFET and three-dimensional transmission lines

2002 ◽  
Vol 50 (6) ◽  
pp. 1603-1608 ◽  
Author(s):  
S. Kimura ◽  
Y. Imai ◽  
S. Yamaguchi ◽  
K. Onodera ◽  
H. Kikuchi
2014 ◽  
Vol 986-987 ◽  
pp. 677-680
Author(s):  
Yu Chen Tian ◽  
Wei Jian Xue ◽  
Ying Zhou ◽  
Lan Jiang

Southwest area of china is the zone of the transmission lines which often happens icing disaster. It is also an earthquake-prone area, also influenced by the interaction between ice and earthquake. This article uses the finite element method (fem), establishing three-dimensional model for steel towers in southwest china, to analyze the dynamic performance of the ice condition and the analysis of seismic action. The aim is to get internal forces for steel towers under the action of earthquake and deformation law along with the change of ice thickness.


2011 ◽  
Vol 2011 (CICMT) ◽  
pp. 000043-000049
Author(s):  
Ehab Abousaif ◽  
Aicha Elshabini ◽  
Fred Barlow

Microwave filters are generally designed with microwave transmission lines. However these filters are typically lossy. The waveguide filters using conventional inductive elements such as metal rods and transverse diaphragm have some disadvantages such as complicated structure, high cost and they can be hard to mass produce. But they also have many advantages such as the capability of high power transmission, a non-radiating structure, and their thermal efficiency. A novel waveguide inductive strip filter embedded in LTCC is introduced in this paper where the disadvantages of the conventional waveguide filters are eliminated. By using LTCC technology, the cost will typically be lower, it can easily be mass produce, and these designs can also be tested easily. The equivalent T-network parameters of the inductive strip mounted in a waveguide and embedded in LTCC substrate were derived. A new iterative technique was used based on the Variation principle. The design formulas and curves of the filter were presented. The design method of the filter was derived by applying the equivalent network of the inductive strip to the usual method of the filter design. A complete set of new curves relating the various filter parameters were introduced. Similar curves can be derived to design similar filters for any frequency band using any dielectric material. Three-dimensional electromagnetic field modeling and simulation was carried out using HFSS (High Frequency Structure Simulator). An optimization process was done for the designed filter. The modeling and the optimization S-parameters curves are shown. This paper introduces a new methodology of designing waveguide inductive strip filters embedded in LTCC. The design methodology was derived and presented with formulas and curves. The design steps are explained and verified by examples and results.


2014 ◽  
Vol 32 (4) ◽  
pp. 599-603 ◽  
Author(s):  
Chongyang Mao ◽  
Xiaobing Zou ◽  
Xinxin Wang

AbstractThe electromagnetic simulation of the monolithic radial transmission lines for future Z-pinch was performed. Focusing on the difference in the maximum transmitted power efficiency between the electromagnetic simulation and the circuit simulation, the monolithic radial transmission lines with different impedance profile (exponential, Gaussian, hyperbolic) were compared. The power efficiency for the exponential line is higher than that for the Gaussian lines and the hyperbolic line, which is similar to that from the circuit simulation. However, all the power efficiencies obtained with the electromagnetic simulation are about 15% lower than those obtained with the circuit simulation, indicating the existence of considerable non-TEM modes and a non-ignorable error in the circuit simulation based on the quasi-TEM mode approximation. In consideration of several monolithic radial transmission lines being stacked together and the flat electrodes required by the stacked lines, the hyperbolic line was compared with the exponential line with several wide radial slots cut on the flat electrodes. While the hyperbolic line has a little bit lower transmitted power efficiency than that of the exponential line, it is much easier in fabrication. For this reason, the hyperbolic line was recommended as the best choice.


Electronics ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 538
Author(s):  
Farhad Larki ◽  
Md Shabiul Islam ◽  
Arash Dehzangi ◽  
Mohammad Tariqul Islam ◽  
Hin Yong Wong

In this paper, we investigate the effect of lateral gate design on performance of a p-type double lateral gate junctionless transistors (DGJLTs) with an air gate gap. The impact of lateral gate length, which modifies the real channel length of the device and gate gap variation down to 50 nm which have been found to be the most influential factors in the performance of the device have been comprehensively investigated. The characteristics are demonstrated and compared with a nominal DGJLTs through three-dimensional technology computer-aided design (TCAD) simulation. At constant channel geometry (thickness and width), when the lateral gate length decreases, the results show constant flatband drain current characteristics while the OFF state current (IOFF) increases significantly. On the other hand, by decreasing the air gap the subthreshold current considerably decreases while the flatband current is constant. Moreover, at a certain gate gap, the gates lose control over the channel and the device simply works as a resistor. Electric field component, carriers’ density, band edge energies, and recombination rate of the carriers inside the channel in depletion and accumulation regimes are analysed to interpret the variation of output characteristics.


2013 ◽  
Vol 838-841 ◽  
pp. 388-391
Author(s):  
Yan Hai Wang ◽  
Ming Hu

Derrick supported by inner suspension and inner backstay group tower is a construction technique commonly used in the construction of overhead transmission lines, the locale sketch and construction technique are complex, and not conducive to the analysis of the key construction and improve the level of decision-making. Through analysis assembly tower construction technology of derrick supported by inner suspension and inner backstay, using engineering visualization design software 3ds Max, the establishment of a three-dimensional model of the tower, the pole, tackle. According to the construction process for dynamic visual simulation, accurate image show the complexity of the construction process. Visual simulation provides an intuitive basis for the construction organization design and construction scheme optimization; enhance the level of construction management.


1999 ◽  
Vol 9 (11) ◽  
pp. 447-449 ◽  
Author(s):  
A. Darwish ◽  
A. Ezzeddine ◽  
H.C. Huang ◽  
M. Mah

2012 ◽  
Vol 166-169 ◽  
pp. 2259-2264
Author(s):  
Li Tian ◽  
Hong Nan Li ◽  
Wen Ming Wang

The behavior of transmission line under three-dimensional seismic excitations is studied by numerical simulation. According to a practical engineering, the transmission towers are modeled by frame elements and the transmission lines are modeled by cable element account for the nonlinearity of the cable. The effects of single-dimensional, two-dimensional and three-dimensional ground motions on the responses of transmission line are investigated using nonlinear time history analysis method, respectively. The results indicate that the longitudinal maximum response of transmission lines can be obtained considering longitudinal ground motion excitation only. The transverse maximum response of transmission lines can be obtained considering transverse ground motion excitation only. Neglecting multiple nature of ground motion in analysis will significantly underestimate the vertical responses of the transmission lines. To obtain an accurate seismic response of transmission lines, three-dimensional ground motion inputs are required.


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