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221.
Saffrine Kingsly Sangeetha Velan Malathi Kanagasabai Sangeetha Subbaraj Yogeshwari Panneer Selvam Bhuvaneswari Balasubramaniyan 《International Journal of Electronics》2019,106(4):620-633
In this paper, a compact, single-section, Ultra-wideband (UWB) coupled-line coupler designed using concentric loop in the signal plane and defect in the ground plane is presented. Bandwidth enhancement is achieved with low coupling at the X-band satellite downlink range to improve the signal strength for defence applications. Return loss greater than 15 dB and isolation greater than 20 dB is achieved over the entire UWB band. The prototype is fabricated and tested to validate the simulation results. Further to detect the quality of the output signal, signal integrity analysis is performed and metrics such as error vector magnitude (EVM), magnitude and phase error, eye pattern, constellation plots and signal to noise ratio are presented for the proposed UWB coupled-line coupler. 相似文献
222.
因PCB上微带线(MSL)与外界电磁能量耦合而生成感应电流(Current),会对敏感器件造成耦合伤害。而目前对此研究的关注度不够,故以带拐角MSL的PCB板内置于开孔屏蔽腔为研究对象,以Current计算为主要切入点,进行多参数耦合特性计算。先建立相应数值模型并验证建模方法有效性后,外置平面波激励源,利用有限元法考察不同计算位置、有无屏蔽腔、MSL夹角大小及拐角补偿等参数变化对电流的影响。结果表明:直MSL上不同计算位置对Current影响不大,其数值都要比MSL弯折时要大,两者差值随频率增加而逐渐减小;谐振点处腔体抑制效果会被弱化甚至完全失效;MSL与电场E平行放置时,迹线需布成短线,MSL与电场E垂直放置时,迹线可布成长线;MSL宽度增加,电流数值会增加但趋势减缓。拐角补偿方法对提高信号完整性(SI)有效,但对降低电磁耦合作用有限。不会影响谐振点出现位置是上述多参数研究的共性结果。 相似文献
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A straight forward design of rectangular slotted microstrip planar antenna fed by 50 ohm microstrip line is proposed for Ku/K band satellite applications. The radiating patch of the antenna occupies an area of 17 × 17 mm2 and fabricated on 1.0 mm‐thick ceramic filled bioplastic composite material substrate whose dielectric constant (εr ) is 10.0. The dual resonant square‐shaped antenna has been formed by inserting four arc shape slots at the corners with the combination of circle and square and wide square shape slot at the center. The results from the measured data show that the antenna has a lower resonant mode impedance bandwidth for S11 < −10 dB is of 18.4% (11.67–14.05 GHz) and upper resonant mode bandwidth is of 8.2% (18.19–19.75 GHz) centered at 12.94 GHz and 19.04 GHz, respectively. The antenna prototype has achieved maximum gains of 3.1 dBi and 4.13 dBi with average radiation efficiencies of 75.3% and 86.4% for the lower band and the upper band, respectively. The numerical data analyses of both the measured and simulated results show relatively good agreement. Moreover, the consistent and symmetrical radiation patters of the proposed antenna make it suitable candidate for the Ku/K band satellite applications. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
225.
Mohammad Reza Salehi Leila Noori Ebrahim Abiri 《International Journal of Electronics》2016,103(11):1882-1893
In this paper, a subsystem consisting of a microstrip bandpass filter and a microstrip low noise amplifier (LNA) is designed for WLAN applications. The proposed filter has a small implementation area (49 mm2), small insertion loss (0.08 dB) and wide fractional bandwidth (FBW) (61%). To design the proposed LNA, the compact microstrip cells, an field effect transistor, and only a lumped capacitor are used. It has a low supply voltage and a low return loss (–40 dB) at the operation frequency. The matching condition of the proposed subsystem is predicted using subsystem analysis, artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS). To design the proposed filter, the transmission matrix of the proposed resonator is obtained and analysed. The performance of the proposed ANN and ANFIS models is tested using the numerical data by four performance measures, namely the correlation coefficient (CC), the mean absolute error (MAE), the average percentage error (APE) and the root mean square error (RMSE). The obtained results show that these models are in good agreement with the numerical data, and a small error between the predicted values and numerical solution is obtained. 相似文献
226.
Adaildo Gomes d''Assunção Maria Rosa M. Lins de Albuquerque Everton N. R. Q. Fernandes 《International Journal of Infrared and Millimeter Waves》2000,21(12):2087-2097
We have studied the behavior of the microstrip lines on lossy biaxial anisotropic dielectric substrates. A spectral-domain moment method is used with the Galerkin testing procedure to determine the dispersion characteristics of single and coupled lines. Modes of both even and odd symmetries are included. It is found that the anisotropy of the substrate has a significant influence on the propagation characteristics. The theory is verified by comparison with previously published data. 相似文献
227.
Lingjian Li 《International Journal of Electronics》2013,100(7):755-765
Microstrip antennas suffer an inherent disadvantage of narrow impedance bandwidth, normally within 5%. In this article, a single layer linear U-slot microstrip patch antenna array is designed, fabricated and characterised. The measured results agree well with the simulated, showing an enhanced impedance bandwidth (voltage standing wave ratio < 2) of 10.6%, ranging from 5.35 to 5.95 GHz, on an FR4 substrate. The antenna array has high efficiency and gain. Only a pair of sidelobes appear in the E plane radiation pattern. The reported linear array design can provide a method of expanding to 4 × N antenna array for satellite to ground communication operating at C band. 相似文献
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229.
提出了一种减缩微带天线雷达散射截面(radar cross section,RCS)的新方法,该方法基于对微带天线表面感应电流的分析,给出可用于降低微带天线RCS的边缘结构。在参考天线的基础上,利用该方法设计了一款新型的低RCS微带天线。该设计天线与参考天线相比,具有同样的辐射性能。使用该方法后,参考天线在与水平面成小角度的平面波照射(掠入射)下,在4~12GHz的宽频带范围内,在φ=-45°~45°角域内的RCS平均值减缩了8.1d B。试验结果证明了该方法的有效性。 相似文献
230.