摘要:

AbstractOddand even‐mode capacitances are computed by a variational method. Trial functions for the charge density distributions are supplied by conformal mapping calculations. Comparison is made with values derived from different methods, and resulting accuracies are discusse

ISSN:0895-2477    

DOI:10.1002/mop.4650080202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe generalized transmission line model (GTLM) analysis has been applied to the study of cylindrical‐circular microstrip antennas. In this study, the equivalent circuit for the circular microstrip antenna excited at TM11mode is given, and formulation of the input impedance is derived. Numerical results of the input impedance for different feed positions and cylinder radii are calculated and presented, and the accuracy of the GTLM analysis is discusse

ISSN:0895-2477    

DOI:10.1002/mop.4650080203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThere exist various hybrid techniques that combine the finite element method (FEM) and surface integral equation‐type (SIE) techniques to solve Maxwell's equations for objects located in unbounded regions. In this article a novel first‐order hybrid approach is considered, which combines the conventional FEM and MoM techniques in two distinct phases by using the field solution initially obtained by FEM to modify the incident field expression of the subsequent MoM analysis p

ISSN:0895-2477    

DOI:10.1002/mop.4650080204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractA flexible catheter antenna with a curved tip is described for transcutaneous microwave treatment of cardiac tachyarrhythmias. In tissue‐equivalent phantom modeling materials, the enlarged inner conductor cap and coaxial choke design yields SAR distributions that accentuate heating of tissue toward the distal end of the catheter antenna. The power reflection coefficient is less than 4

ISSN:0895-2477    

DOI:10.1002/mop.4650080205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractA three‐phase‐shift‐controlled wavelength tunable optical filter is proposed. Theoretical calculation based on the transfer matrix method indicates a tuning range of more than 30 Å. The peak gain and bandwidth are almost constant during tuning. The side‐mode suppression is ov

ISSN:0895-2477    

DOI:10.1002/mop.4650080206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractWe present the design of an extremely high extinction ratio metal‐clad GaAs/GaAlAs TE‐pass polarizer with the buffer layer also of GaAlAs. Our investigations on the effect of the buffer layer index on the extinction of TM modes show that high index buffers corresponding to GaAlAs can give an extremely high TM loss by a suitable choice of Al concentration. The choice of this type of buffer also eliminates the depositon step, during device fabrication, required for materials like SiN and oxide buffer layers reported earl

ISSN:0895-2477    

DOI:10.1002/mop.4650080207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractIn the analysis of antennas and scattering problems by the finite‐difference‐time‐domain (FDTD) method, the dimensions of the problem space are primarily determined by the quality of the radiation boundary condition (RBC) that is used to truncate the computational grid. The performance of the recently proposed higher‐order boundary conditions in cases of practical importance is often worse than the standard Mur‐second‐order condition. In the present article we will show that the reason for this unexpected result is the inability of this type of one‐way wave equation to deal with the evanescent or inhomogeneous plane‐wave part of the field. On the basis of this consideration we have constructed a new semiglobal operator that does have the required property. By combining this operator with the unusual Mur‐second‐order condition one arrives at an RBC with a much better performance. The novel RBC can also be used to anal

ISSN:0895-2477    

DOI:10.1002/mop.4650080208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThis work presents an automatic network analyzer (ANA) using a single six‐port reflectometer in the W frequency band (75‐110 GHz). Its analysis, design, and testing are described. A calibration procedure requiring two standards and a new calibration technique are used to determine the full scattering parameters of the device under test (DUT). Finally, a comparison between experimental results performed with the six‐port network analyzer and the other measurement systems available in the W frequency band is pres

ISSN:0895-2477    

DOI:10.1002/mop.4650080209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractFinite‐difference methods are standard techniques for solving the differential form of Maxwell's equations. In spite of many advantages, a drawback of the technique is how to implement an absorbing boundary condition in an essentially exact fashion. In this article an absorbing boundary condition is proposed based on the Green's functions arising in integral equations. The radiation condition in this approach is built up iteratively as the solution progresses utilizing the Green's function. In the proposed method only two layers of meshes outside the boundary may be sufficient. Examples have been presented for the electrostatic case to illustrate the accuracy and convergence of this new techniqu

ISSN:0895-2477    

DOI:10.1002/mop.4650080210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractBased on programmable polarization‐optical neighborhood interconnection, which is a stacked integration of rotatable crystal plates for beam splitting the controllable wave plates for polarization direction controlling, a kind of morphological processor with real‐time programmable structure elements is developed. It is compact in structure and effective as well as stable in performa

ISSN:0895-2477    

DOI:10.1002/mop.4650080211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY