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1.
采用矩量法结合复镜像理论计算了近地水平对数周期天线的阻抗矩阵,利用微波网络理论处理馈源问题,从而得到天线的电流分布,最后采用鞍点法计算了远区辐射场。计算结果与有关文献相吻合,证实了该方法的正确性和通用性。  相似文献   

2.
快速计算通信天线宽频带内的电特性   总被引:1,自引:1,他引:0  
在分析通信天线宽频事内的特性时,一般需要选取许多频点采用矩量法逐点求解天线上的电流分布,计算时间长。研究了一种对电流系统矩阵[I]进行频域插值的方法来快速分析天线宽频带内的电特性。该方法先利用矩量法直接求出少数较大间隔的频率点上的电流展开系数矩阵[I],然后利用这些采样频点上的[I]矩阵来插值计算其它频点上的电流展开系数矩阵的元素。采用该方法分析了几个不同天线,与直接采用矩量法计算相比,该方法计算时间显著减少,计算误差很小。  相似文献   

3.
本文提出了一种快速远场近似(FAFFA)加速的混合物理光学-矩量法(PO-MM),利用FAFFA加速计算矩阵方程中的矩阵矢量积,明显提高了计算效率.对物体表面上的远场组之间的耦合作用推导出了一组简洁的计算公式,并分析了计算复杂度.复杂金属组合体上线天线输入导纳、互导纳和方向性图的计算结果与文献结果一致.利用该方法分析计算了一个舰船模型上线天线的电磁特性.数值结果表明了这种方法的正确性和工程应用中的有效性.  相似文献   

4.
FAFFA加速的PO-MM研究复杂金属载体上线天线电磁特性   总被引:3,自引:0,他引:3       下载免费PDF全文
华夷和  徐金平  牛臻弋 《电子学报》2003,31(Z1):2045-2049
本文提出了一种快速远场近似(FAFFA)加速的混合物理光学矩量法(POMM),利用FAFFA加速计算矩阵方程中的矩阵矢量积,明显提高了计算效率.对物体表面上的远场组之间的耦合作用推导出了一组简洁的计算公式,并分析了计算复杂度.复杂金属组合体上线天线输入导纳、互导纳和方向性图的计算结果与文献结果一致.利用该方法分析计算了一个舰船模型上线天线的电磁特性.数值结果表明了这种方法的正确性和工程应用中的有效性.  相似文献   

5.
针对传统矩量法分析天线阵列效率低的问题,给出了一种分析蝶形天线阵列电磁辐射特性的有效数值方法,该方法基于特征基函数法(CBFM )和等效偶极矩法(EDM ),不仅可以加速阻抗矩阵的产生,还可根据特征基函数(CBFs)的阶数和子域的数目调节系数矩阵的维数,从而可以采用直接法求解缩减矩阵方程,与传统矩量法(MoM)相比,显著地减小了运算量。数值结果验证了蝶形天线阵列的方向图并证实了该方法的精确性和有效性。  相似文献   

6.
匡勇  姜新发 《天线技术》1998,(14):22-26
采用等效电路与矩量法相结合的方法,建立波导宽边纵向缝隙数学模型。它既克服了一般效电路分析方法无法进行频率特性分析的缺点,又克服了利用一般矩量法求解积分方程仅适应于几个缝的小阵的缺点。这种分析方法缝隙的辐射导纳是由矩量法直接求解的,与站平时征于谐振状态无关,因此,可以分析天线性能随频率的变化情况。介绍的分析方法包括一互耦,考虑了波导的壁厚、利用该分析方法,对宽边纵向缝隙阵端馈与中心馈电的两种情况进行  相似文献   

7.
AWE技术结合矩量法分析某型八木天线   总被引:3,自引:0,他引:3  
应用AWE技术结合矩量法分析了某型八木天线的辐射特性。首先采用矩量法求解八木天线的电场积分方程,得到某一频率点的电流分布和输入阻抗;通过Pade逼近^[5]获得任意频率的导纳,从而得到该型八木天线的频率响应;给出了天线上的电流分布、输入导纳以及辐射方向图,对AWE/MOM与MOM的计算结果进行了比较,两者比较接近,但AWE/MOM可大大加快计算速度。  相似文献   

8.
VHF宽带小型化套筒天线的优化设计   总被引:6,自引:3,他引:3  
研究了VHF宽带小型化套筒天线的设计与制作。采用遗传算法与模拟退火法相结合的优化方法,对套筒天线的结构参数以及宽带匹配网络的元件值进行一体化设计。分别采用外插收敛法、[Z]矩阵插值法以及小波变换法来提高矩量法分析计算天线的速度。利用该方法成功的设计了两副全向宽带小型化的套筒天线。  相似文献   

9.
无线设备互调干扰仿真分析   总被引:1,自引:0,他引:1  
系统电磁兼容(EMC)设计中,无线设备间互调干扰是非常严重的一个问题.本文首先建立了无线设备间互调干扰量的分析模型,并采用矩量法结合微波网络的方法求出互调干扰模型中最重要的参数天线间耦合度,然后把发射及接收设备的给定数据代入干扰模型算出发射机和接收机间互调干扰的量级.经过仿真数据与实测数据的对比,证明该方法理论正确,计算精度较高,文章最后给出了仿真实例.  相似文献   

10.
采用矩量法(MOM)结合一致性几何绕射理论(UTD)来分析和计算大型平面阵列天线的辐射特性。大型天线阵列含有很多的辐射单元,单独应用矩量法求解时,未知数太多,计算速度慢。而应用MOM-UTD混合方法,未知数的数量大大少于单独用矩量法时的未知数的数量。本文以振子组成的平面阵列为例,说明该方法如何应用。最后给出了数值解的结果,并与单独用矩量法得到的结果进行了比较。比较表明,该方法是有效的、准确的。  相似文献   

11.
边界积分法及连接算法分析任意腔体的散射   总被引:3,自引:0,他引:3  
聂小春  葛德彪 《微波学报》1999,15(4):334-338
本文利用边界积分法分析二维任意腔体的散射,给出一种基于微波网络原理的连接算法,将腔体分为几段,分别用积分方程法计算每段的广义导纳矩阵,然后利用连接算法将各段连接,得到整个腔体的口径导纳矩阵,最后由广义网络原理求解腔体的等效磁流及后向散射场。本文方法可作为一种机辅设计算法。  相似文献   

12.
The electromagnetic scattering from arbitrary three-dimensional cavities is presented. To alleviate computational constraints for three-dimensional problems, a connection scheme is developed based on microwave network theory. This scheme allows the cavity to be divided into sections and each section to be analyzed independently of the rest of the cavity. Each section of the cavity is represented by a generalized admittance matrix which if formulated via a boundary-integral equation approach. Using the concept of input and load admittance, the aperture admittance matrix of the cavity can be derived by cascading the admittance matrices of individual sections. Once the cavity aperture admittance matrix is obtained, the aperture electric field and the backscattered field are found by the standard generalized network formulation. Numerical results are compared against modal solutions of regularly shaped cavities with good agreement. This connection scheme leads to a reduction in computational resources, especially for cavities with one dimension much larger than the other two  相似文献   

13.
在天线的设计过程中,天线表面的电流分布将对天线的性能产生重要影响。本文介绍了一种双圆柱体结构全向天线阵列的表面电流及等效端口导纳矩阵的计算方法,根据这个算法,本文计算了在一定物理尺寸下该天线阵列的电流分布和端口导纳矩阵。数值计算显示这种算法是可行的,结果是令人满意的。  相似文献   

14.
An array antenna is modeled after a linear multipole filter, one part of which is connected to a distant source, radiating in a specified direction, while the relations between the other parts are characterized by the antenna admittance matrix. This modeling technique is applied to an array of parallel linear wire antennas. It is shown how the array admittance matrix can be evaluated numerically by a discrete quantization of the Maxwell’s equations with the proper boundary conditions (Harrington’s method of moments). The admittance matrix is then used to formulate the optimum signal processing for transmission (maximization of antenna gain, with or without constraints) and for reception (maximization of signalto-noise ratio). Along with the model of the array antenna that is submitted, a method of signal processing is developed in which accurate estimates are included of the losses that occur within the array elements as well as of the coupling between elements and of the noise arising in the receiving system. The antenna designer can thus optimize the geometric configuration of the array and study the phenomenon of superdirectivity with a more realistic approach than was hitherto possible.  相似文献   

15.
We use planar slot antennas proximal to proteins in solution to detect changes in conformation. The antennas are attached to fused-quartz or glass sample holders and the cuvette/antenna assembly is placed in the sample holder of an optical spectrophotomer (either UV/VIS or fluorescence polarization), allowing simultaneous dielectric and optical measurements. Return loss is recorded using a vector network analyzer. This system was used to study the equilibrium thermal unfolding and refolding of a small globular protein, as well as the binding of small hormones to a receptor. Good agreement between optical and microwave measurements was obtained for all systems studied. We show that microwave measurements can be made at protein concentrations as low as 0.3 ng/mL (19 pM), several orders of magnitude lower than that required for optical spectroscopy. The results from these experiments demonstrate that resonant slot antennas can be used to detect changes in protein conformation and the presence of microwave radiation does not perturb the system under study.  相似文献   

16.
导电平板上任意孔缝的TM波散射及传输特性分析   总被引:2,自引:0,他引:2  
该文利用边界积分法分析导电平板上任意孔缝的TM波散射及传输特性,并引入了一种基于微波网络原理的连接算法以缓解计算机内存对所计算孔缝尺寸的限制。首先将孔缝内腔分为几段,用积分方程法分别计算每段的广义导纳矩阵,然后利用连接算法将各段连接起来得到整个孔缝的口径导纳矩阵,最后由广义网络原理求解孔缝的等效磁流、后向散射场以及传输系数。  相似文献   

17.
A modular technique originally proposed for waveguide junctions, the multimode equivalent network approach based on the integral equation formulation (IEMEN), is extended to the analysis of multilayer frequency selective surfaces integrated with waveguide array antennas. This technique represents each layer and transition between layers in terms of a generalized impedance or admittance matrix, obtained directly from the solution of an integral equation with reduced kernel. Thanks to the adopted formulation, the integral equation needs to be solved only in a limited set of frequency points. The IEMEN method is validated by comparison with results available in literature.  相似文献   

18.
Tao WANG  Yong WANG  Yue ZHANG 《通信学报》2015,36(10):263-270
In order to exchange information among k users using the technology of physical-layer network coding in the multiple input multiple output Y two-way relay channels,the GSA-GSA scheme was proposed,using the technology of general signal alignment during the uplink and the downlink.The signals were exchanged between every source node align in a transformed subspace,rather than the direct subspace.This was realized by jointly designing the precoding matrices at all source nodes and the processing matrix at the relay.The constraints of the number of sending and receiving antennas and the sum rate of proposed scheme were analyzed.In simulation,it can figure out that the proposed scheme needs fewer antennas in the whole system and can improve the achievable system sum rate under the same SNR and degrees of freedom.  相似文献   

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