共查询到15条相似文献,搜索用时 140 毫秒
1.
围绕建设中国大学金课的核心思想,结合天线综合实践课程的教学内容和目标,以用于空间微波能收集的整流天线设计为例,提出了面向工程应用的综合实践教学模式.该模式采用基础设计、创新设计、综合训练和工程总结的阶梯式教学过程.实践内容选择工程前沿课题,既能提高学生兴趣,又具有一定的综合挑战性,可有效地提升学生解决复杂工程问题的... 相似文献
2.
3.
4.
黄太艳 《湖北成人教育学院学报》2013,19(2)
园路是园林景观重要元素之一.园路的弧线可以通过丰富的变化让人体会到不同的美感.园路设置时应注意“因景设路、因路得景”.道路要结合建筑水体来规划,树木景点的布置要围绕道路进行,相互依存、渗透,同时把园内的景点串联起来,贯穿园内所有的景点.因此,园林景观设计中园路铺设方法的分析和运用就显得十分重要. 相似文献
5.
6.
HUANG Biao YAN Guo-zheng LI Qian-ru 《浙江大学学报(A卷英文版)》2007,8(10):1560-1567
Antenna is very crucial to radiotelemetry capsules which can measure the physiological parameters of the gastroin- testinal (GI) tract. The objective of this paper is to design a novel spiral slots microstrip patch antenna for the radiotelemetry capsules communicating with external recorder at 915 MHz located in ISM (Industry, Science, and Medical) bands. The microstrip patch antenna is designed and evaluated using the finite-difference time-domain (FDTD) method. Return loss characteristics and the effect of the human body on resonant frequency are analyzed, and the performances of radiation patterns at different positions of the human alimentary tract are also estimated. Finally, specific absorption rate (SAR) computations are performed, and the peak 1-g and 10-g SAR values are calculated. According to the peak SAR values, the maximum delivered power for the designed antenna was found so that the SAR values of the antenna satisfy the ANSI (American National Standards Institute) limitations. 相似文献
7.
为了有效地计算非矩形光子晶体带隙结构,将非正交坐标系用于时域有限差分(FDTD)方法中,在非正交坐标系下离散麦克斯韦方程组,重新推导了FDTD递推公式。将本征色散变量表达方法应用到非正交坐标系,提高了计算的准确性。用这种非正交的FDTD方法研究了非矩形光子晶体横磁场模的带隙结构。数值模拟结果验证了上述计算方法的有效性。 相似文献
8.
The micro-genetic algorithm(MGA)optimization combined with the finite-difference time-domain(FDTD)method is applied to design a band-notched ultra wide-band(UWB)antenna. A U-type slot on a stepped U-type UWB monopole is used to obtain the band-notched characteristic for 5 GHz wireless local area network(WLAN)band. The measured results show that voltage standing wave ration(VSWR)less than 2 covers 3.1-10.6 GHz operating band and VSWR more than 2 is within 5.150-5.825 GHz notched one with the highest value of 5.6. Agreement among the calculated, HFSS simulated and measured results validates the effectiveness of this MGA-FDTD method, which is efficient for UWB antennas design. 相似文献
9.
吴小倩 《浙江教育学院学报》2008,(6):62-67
将基于FDTD的由粗到细网格逐步逼近计算电磁场的方法应用于内置带裂缝的金属谐振腔的电磁场的计算,并研究网格从大到小的变化过程中,始终保持谐振腔边界面的位置不变,该方法的计算精度和效率.结果表明:该方法与FDTD方法计算电磁场的精度一致,但效率明显提高. 相似文献
10.
Mohammed Ahmed ZHONG Shun shi 《上海大学学报(英文版)》1999,3(4):279-281
1 Introduction Thesuccessfulcommericalapplicationsofwirelesstechnologydemandappropriateantennas.Typically,adualpolarizationoperationsuchassimultaneousvertialandhorizontalpolarizationantennawithlowprofile,smallsize,andlightweightisrequiredforwidespre… 相似文献
11.
为了有效地计算矩形介质谐振器的主模,对变换方向隐式(ADI)时域有限差分(FDTD)算法的迭代系数进行修正,即添加各向异性参数修正相速度误差,从而减少数值色散,提高计算精度。给出了改进后的三维ADI—FDTD计算公式,并对算法的稳定性、色散关系以及各向异性参数的选取进行了研究,数值结果证明了所给方法的有效性。文中还用这种方法计算了位于电磁带隙结构上的矩形介质谐振器天线的方向图。 相似文献
12.
汪伟 《上海大学学报(英文版)》2006,(3)
In order to meet the urgent needs in wireless com-munications , microwave i mage synthetic aperture ra-dars (SAR) ,and electronic warfare systems ,this dis-sertation studies several types of broadband dual-polar-ized planar antenna elements and arrays ,and proposesa few of novel designs with experi mental verification.The main accomplishments reported in the dissertationare as follows . First ,the phenomena of symmetryin electromagne-tism, both in theory and in applications , are sum-marized.… 相似文献
13.
在三维柱坐标系下给出了麦克斯韦方程在完全匹配层(PML)吸收边界条件中的时域有限差分(PDTD)表达式,从而把FDTD推广到三维复柱坐标系中并加以实现.为了模拟柱面波在空间的传播,给出了在柱坐标系下完整的总场和散射场的连接边界条件.最后,模拟了柱面波在自由空间中的传播及空心圆柱体在柱面波入射下的近场和远场散射特性. 相似文献
14.
汪伟 《上海大学学报(英文版)》2006,10(3):282-282
In order to meet the urgent needs in wireless communications, microwave image synthetic aperture radars (SAR), and electronic warfare systems, this dissertation studies several types of broadband dual-polarized planar antenna elements and arrays, and proposes a few of novel designs with experimental verification. The main accomplishments reported in the dissertation are as follows. 相似文献
15.
为了广泛应用射频识别(RFID)技术,设计了一种标签天线。利用计算电磁场时域有限差分/矩量法的混合方法,分析了复杂环境中RFID天线的性能。将计算结果和实验进行比较,验证了混合方法计算结果的准确性,对RFID天线的工程设计有一定参考价值。 相似文献