On the Field Distribution in Rectangular Apertures Using Surface Patch Modeling

1975 ◽  
Vol 53 (9) ◽  
pp. 869-873
Author(s):  
R. J. Spiegel ◽  
D. E. Young
Keyword(s):  
Integral Equation ◽  
Plane Wave ◽  
Field Distribution ◽  
Method Of Moments ◽  
Numerical Stability ◽  
Surface Patch ◽  
Point Matching ◽  
Conducting Screen ◽  
Plane Wave Diffraction ◽  
Stability Of The Solution

In this paper the H integral equation is investigated for the problem of plane wave diffraction by a rectangular aperture cut into an infinite, perfectly conducting screen. The field distribution in the aperture is calculated by the application of the method of moments with point matching and pulse expansion functions. Various sized apertures are considered and the numerical stability of the solution is discussed.

Scattering by a perfectly conducting multislotted cylinder

1992 ◽  
Vol 70 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Mousa I. Hussein ◽  
M. Hamid
Keyword(s):  
Integral Equation ◽  
Circular Cylinder ◽  
Plane Wave ◽  
Method Of Moments ◽  
Boundary Value ◽  
Integral Equation Method ◽  
Equation Method ◽  
Incident Plane Wave ◽  
Incident Plane ◽  
Field Integral

The problem of scattering by a perfectly conducting multislotted circular cylinder excited by a z-polarized incident plane wave is presented. The solution is carried out using two methods of analysis. In the first method, the fields in and around the cylinder are found in terms of the aperture fields, using the boundary value technique. Then Galerkin's method is introduced to solve for the unknown aperture fields. In the second method, the aperture-field integral equation method is employed and the fields in and around the cylinder are found in terms of the aperture fields, while the resulting equations are solved using the method of moments. Results are obtained and presented using the two methods.

scholarly journals Closed-Form Expressions for Numerical Evaluation of Self-Impedance Terms Involved on Wire Antenna Analysis by the Method of Moments

Electronics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1316
Author(s):  
Carlos-Ivan Paez-Rueda ◽  
Arturo Fajardo ◽  
Manuel Pérez ◽  
Gabriel Perilla
Keyword(s):  
Numerical Integration ◽  
Method Of Moments ◽  
Computing Time ◽  
Basis Functions ◽  
Wire Antenna ◽  
Complex Geometries ◽  
Point Matching ◽  
Piecewise Constant ◽  
Matching Procedure ◽  
Time Required

This paper proposes new closed expressions of self-impedance using the Method of Moments with the Point Matching Procedure and piecewise constant and linear basis functions in different configurations, which allow saving computing time for the solution of wire antennas with complex geometries. The new expressions have complexity O(1) with well-defined theoretical bound errors. They were compared with an adaptive numerical integration. We obtain an accuracy between 7 and 16 digits depending on the chosen basis function and segmentation used. Besides, the computing time involved in the calculation of the self-impedance terms was evaluated and compared with the time required by the adaptative quadrature integration solution of the same problem. Expressions have a run-time bounded between 50 and 200 times faster than an adaptive numerical integration assuming full computation of all constant of the expressions.

scholarly journals Ultrasonic Scattered Field Distribution of One and Two Cylindrical Solids with Phased Array Technique

2019 ◽  
Vol 32 (1) ◽  
Author(s):  
Xiaozhou Liu ◽  
Jian Ma ◽  
Haibin Wang ◽  
Sha Gao ◽  
Yifeng Li ◽  
...  
Keyword(s):  
Plane Wave ◽  
Field Distribution ◽  
Scattered Field ◽  
Phased Array ◽  
Simulation Analysis ◽  
Plane Waves ◽  
Theoretical Solution ◽  
Steel Matrix ◽  
Field Distributions ◽  
Scattered Fields

AbstractThe scattered fields of plane waves in a solid from a cylinder or sphere are critical in determining its acoustic characteristics as well as in engineering applications. This paper investigates the scattered field distributions of different incident waves created by elastic cylinders embedded in an elastic isotropic medium. Scattered waves, including longitudinal and transverse waves both inside and outside the cylinder, are described with specific modalities under an incident plane wave. A model with a scatterer embedded in a structural steel matrix and filled with aluminum is developed for comparison with the theoretical solution. The frequency of the plane wave ranged from 235 kHz to 2348 kHz, which corresponds to scaling factors from 0.5 to 5. Scattered field distributions in matrix materials blocked by an elastic cylindrical solid have been obtained by simulation or calculated using existing parameters. The simulation results are in good agreement with the theoretical solution, which supports the correctness of the simulation analysis. Furthermore, ultrasonic phased arrays are used to study scattered fields by changing the characteristics of the incident wave. On this foundation, a partial preliminary study of the scattered field distribution of double cylinders in a solid has been carried out, and the scattered field distribution at a given distance has been found to exhibit particular behaviors at different moments. Further studies on directivities and scattered fields are expected to improve the quantification of scattered images in isotropic solid materials by the phased array technique.

Sign in / Sign up

Export Citation Format

Share Document