Study of TE and TM modes in waveguides of arbitrary cross-section using an FD-TD formulation
01 Dec 1992-Vol. 139, Iss: 6, pp 491-494
TL;DR: In this article, the cutoff frequencies of TE and TM modes in waveguides of arbitrary cross-section were obtained using the finite-difference method in the time domain for determining cutoff wavelengths and modal field distributions in a square coaxial waveguide.
Abstract: The paper describes the application of the finite-difference method in the time domain for obtaining the cutoff frequencies of TE and TM modes in waveguides of arbitrary cross-section. Maxwell's equations are discretised in a two-dimensional space. The application of the discrete Fourier transform also provides the spatial distribution of the modes in the cross-section of the waveguide. The method is validated against rectangular and a circular waveguides, each with a known cutoff spectrum. Finally, the method is applied to determine cutoff wavelengths and modal field distributions in a square coaxial waveguide.
Citations
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TL;DR: This survey presents some of the significant works that made the FDTD method so popular, and tracks its development up to the present-day state-of-the-art in several areas.
Abstract: The finite-difference time-domain (FDTD) method is arguably the most popular numerical method for the solution of problems in electromagnetics. Although the FDTD method has existed for nearly 30 years, its popularity continues to grow as computing costs continue to decline. Furthermore, extensions and enhancements to the method are continually being published, which further broaden its appeal. Because of the tremendous amount of FDTD-related research activity, tracking the FDTD literature can be a daunting task. We present a selective survey of FDTD publications. This survey presents some of the significant works that made the FDTD method so popular, and tracks its development up to the present-day state-of-the-art in several areas. An "on-line" BibT/sub E/X database, which contains bibliographic information about many FDTD publications, is also presented. >
237 citations
Cites background from "Study of TE and TM modes in wavegui..."
...Navarro and co-workers [218], [219], [220] have also investigated rectangular, circular, and T-junctions in square coaxial waveguides, and narrow-wall multiple slot couplers....
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TL;DR: In this paper, an extension of the finite difference time domain is applied to solve the Schrodinger equation, and a systematic analysis of stability and convergence of this technique is carried out.
Abstract: An extension of the finite difference time domain is applied to solve the Schrodinger equation. A systematic analysis of stability and convergence of this technique is carried out in this article. The numerical scheme used to solve the Schrodinger equation differs from the scheme found in electromagnetics. Also, the unit cell employed to model quantum devices is different from the Yee cell used by the electrical engineering community. A bound for the time step is derived to ensure stability. Several numerical experiments in quantum structures demonstrate the accuracy of a second order, comparable to the analysis of electromagnetic devices with the Yee cell.
87 citations
TL;DR: In this paper, a single-layer corporate-feed slot array antenna is presented, which is realized by adopting hollow rectangular coaxial lines for the corporate feed circuit and placing the feeding circuit and the radiating elements in the same layer.
Abstract: A single-layer corporate-feed slot array antenna is presented. The single-layer structure is realized by adopting hollow rectangular coaxial lines for the corporate-feed circuit and placing the feeding circuit and the radiating elements in the same layer. Based on this, a 16 × 16-element slot array for the 60-GHz band is designed and fabricated by diffusion bonding of laminated thin copper plates. A 32.3 dBi gain and 72.2% antenna efficiency are confirmed at the design frequency of 61.5 GHz in the measurements. The 1-dB down gain bandwidth is 8.8%. The conductor loss of the antenna is estimated to be 0.85 dB at 61.5 GHz.
27 citations
Cites methods from "Study of TE and TM modes in wavegui..."
...The cutoff frequencies of the higher-order modes are computed by utilizing the FDTD method [23]....
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TL;DR: In this paper, the scaled boundary finite element method (SBFEM) is developed for the solution of waveguide eigenvalue problems, which combines the advantages of the finite element and the boundary element method.
Abstract: The scaled boundary finite element method (SBFEM) is developed for the solution of waveguide eigenvalue problems, which combines the advantages of the finite element method and the boundary element method. A new variational principle formulation to derive the SBFEM equations for waveguide is developed. An equation of the dynamic stiffness matrix for waveguide representing the relationship between the ‘flux’ and the longitudinal field components at the discretised boundary is established. A continued fraction solution in terms of eigenvalue is obtained. By using the continued fraction solution and introducing auxiliary variables, the flux–longitudinal field relationship is formulated as a system of linear equations in eigenvalue then a generalised eigenvalue equation is obtained. The eigenvalues of rectangular, L-shaped, vaned rectangular and quadruple corner-cut ridged square waveguides are calculated and compared with analytical solution and other numerical methods. The results show that the present method yields excellent results, high precision and less computational time and rapid convergence is observed.
22 citations
TL;DR: In this article, a hollow rectangular coaxial line is designed for the 60 GHz band and fabricated by diffusion bonding of laminated thin metal plates, and a low transmission loss of 0.036 dB/cm is confirmed at 60 GHz by measurement.
Abstract: A hollow rectangular coaxial line is designed for the 60-GHz band and fabricated by diffusion bonding of laminated thin metal plates. A low transmission loss of 0.036 dB/cm is confirmed at 60 GHz by measurement in a designed rectangular coaxial line. The suspended inner conductor is supported by a thin plate. A longitudinal slot excited by the metal support and its linear array are presented. The proposed structures are verified by comparing the measured results with the designed ones. The 1.5% bandwidth of the linear array for reflection below $-{\hbox{14 dB}}$ is obtained by the measurement.
22 citations
Cites methods from "Study of TE and TM modes in wavegui..."
...using the finite-difference time-domain (FDTD) method [11], the Schwarz–Christoffel conformal mapping [12], and the Wheeler Incremental Inductance (WII) rule [13], respectively....
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References
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Abstract: Maxwell's equations are replaced by a set of finite difference equations. It is shown that if one chooses the field points appropriately, the set of finite difference equations is applicable for a boundary condition involving perfectly conducting surfaces. An example is given of the scattering of an electromagnetic pulse by a perfectly conducting cylinder.
14,070 citations
Book•
01 Jul 1988
TL;DR: This book focuses on the application of the FFT in a variety of areas: Biomedical engineering, mechanical analysis, analysis of stock market data, geophysical analysis, and the conventional radar communications field.
Abstract: The Fast Fourier Transform (FFT) is a mathematical method widely used in signal processing. This book focuses on the application of the FFT in a variety of areas: Biomedical engineering, mechanical analysis, analysis of stock market data, geophysical analysis, and the conventional radar communications field.
1,432 citations
TL;DR: In this paper, a numerical method for the solution of the electromagnetic fields within an arbitrary dielectric scatterer of the order of one wavelength in diameter is described, and an error of less than /spl plusmn/10 percent in locating and evaluating the standing wave peaks within the cylinder is achieved for a program execution time of 1 min.
Abstract: A numerical method is described for the solution of the electromagnetic fields within an arbitrary dielectric scatterer of the order of one wavelength in diameter. The method treats the irradiation of the scatterer as an initial value problem. At t = 0, a plane-wave source of frequency f is assumed to be turned on. The diffraction of waves from this source is modeled by repeatedly solving a finite-difference analog of the time-dependent Maxwell's equations. Time stepping is continued until sinusoidual steady-state field values are observed at all points within the scatterer. The envelope of the standing wave is taken as the steady-state scattered field. As an example of this method, the computed results for a dielectric cylinder scatterer are presented. An error of less than /spl plusmn/10 percent in locating and evaluating the standing-wave peaks within the cylinder is achieved for a program execution time of 1 min. The extension of this method to the solution of the fields within three-dimensional dielectric scatterers is outlined.
1,300 citations
TL;DR: In this paper, the authors describe the application of the finite-difference method in the time domain to the solution of 3D eigenvalue problems, where the equations are discretized in space and time, and steady state solutions are then obtained via Fourier transform.
Abstract: This paper describes the application of the finite-difference method in the time domain to the solution of three-dimensional (3-D) eigenvalue problems. Maxwell's equations are discretized in space and time, and steady-state solutions are then obtained via Fourier transform. While achieving the same accuracy and versatility as the TLM method, the finite-difference-time-domain (FD-TD) method requires less than half the CPU time and memory under identical simulation conditions. Other advantages over the TLM method include the absence of dielectric boundary errors in the treatment of 3-D inhomogeneous planar structures, such as microstrip. Some numerical results, including dispersion curves of a microstrip on anisotropic substrate, are presented.
180 citations