Analysis of waveguide multi-ports discontinuities by the helmholtz weak form and mode expansion

Design and Analysis of Several Kinds of Dielectric Lens Antennas

“…Detailed information of the WF-FEM has been presented in other paper [4,5], so the theory of WF-FEM will not be repeated here. However, it is necessary to testify the accuracy of our program at first, and the scattering problem of a dielectric cylinder (ε r = 2.1) is used to do this job.…”

“…To analyze the electromagnetic characteristics of the lens, physical optics method (PO) and geometrical optics method (GO) are the most commonly used methods, but these methods are accurate only for the refractive lens under the condition of curvature radius of lens surface is greater than a wavelength, and these methods are not applicable to the analysis of diffractive lens whose diffractive steps size is less than a wavelength in most cases and the coupling effect among the diffractive zones can not be neglected. In this paper, FEM based on the weak form of Helmholtz equation [4,5] (called WF-FEM latter) is used to analyze the lens antenna, as everyone know, FEM is a full-wave method and is powerful to solve complex boundary value problems. The advantage of this WF-FEM arithmetic is that it is not needed to deduce variational formulation and do inner product in this arithmetic, which is an unavoidable procedure in the traditional FEM arithmetic that is based on Ritz method.…”

Dielectric lens antennas designed for millimeter-wave monopulse system

“…The numerical methods used to analyze lenses are usually GO and PO methods [4][5][6][7], but these two methods are inaccurate in some cases [8] and the accuracies of these two method for new problems are not able to be predicted. As a result, a full-wave method -FEM based on the weak form of Helmholtz equation [9] (called WF-FEM latter) is used to analyze the radiation pattern of the lens antenna in this paper. Two lens-the wave front matching (WFM) lens antenna and shaped lens (SL) antenna are analyzed using WF-FEM, the radiation pattern and the frequency characteristics of these two antennas are given first, and then the sum and difference beams are presented.…”

“…The FEM region Q is enclosed by absorbing boundary conditions (ABC) 17 which is used to simulate a boundary where the wave can propagate through without any reflection. Details of the WF-FEM can be found in [9]. After the fields in region Q are obtained, the far field at any point outside Q can be obtained by *This work is supported by the NSFC (60571028) G (r O(r,r r) Esc = E (r') GOrr -Go( ' E( Where G0(r,r')= 4 HO2)(k0r-r') , F is any path that encircles the scattering object in region Q.…”

Full-Wave Analysis of Monopulse Dielectric Lens Antennas at W-band

“…However, these two methods are inaccurate in some cases [9] and the accuracy of these two methods for the application to new problems is unpredictable. Therefore, in order to analyze the radiation pattern of the lens antenna, finite element method (FEM) based on the weak form of Helmholtz equation [10][11][12][13] (called WF-FEM latter) is employed in this paper. It is well-known that FEM is a full-wave method and powerful to solve complex boundary value problems.…”