Abstract: Printed antennas are becoming one of the most popular designs in personal wireless communications systems. In this paper, the design of a novel tapered meander line antenna is presented. The design analysis and characterization of the antenna is performed using the finite difference time domain technique and experimental verifications are performed to ensure the effectiveness of the n...

To facilitate the design of high power klystrons an investigation into the reliability and accuracy of three modern particle-in-cell codes was performed. A 150MW S-band klystron for which measurements were available was used for this comparison. The field calculations of the particle-in-cell codes are based on a finite difference time domain scheme, and use a port approximation to speed up the ...

We developed a magnetic field probe consisting of a LiNbO3 optical waveguide modulator and a loop antenna element for accurate magnetic near-field measurements in the gigahertz range. We confirmed the probe invasiveness by measuring magnetic field distributions above a patch antenna operating at 2.49 GHz using the probe. Then we compared those measured results with those for shielded loop probe...

We have found a blueshift in the cavity modes confined in two-dimensional photonic crystal microcavities when the thickness of the slab was varied uniformly by accurate dry etching. The shifts in the wavelength of the cavity modes were around 2 nm towards shorter wavelengths per nanometer reduced in the thickness of the slab. Three-dimensional plane wave expansion calculations showed that the o...

We have previously proposed a method of cutting bones using high intensity focused ultrasound. The goal of the method is to cut bones in a body without incising skin, but the condition under which bones are cut properly is so sensitive that 1 mm of displacement makes cutting bones fail resulting in necrosis around the focal point. In this paper, we have developed a focused ultrasound propagatio...

Comparison between Staggered and Unstaggered Finite-Difference Time-Domain Grids for Few-Cycle Temporal Optical Soliton Propagation L. Gilles,∗,† S. C. Hagness,∗ and L. Vázquez† ∗Department of Electrical and Computer Engineering, University of Wisconsin, 1415 Engineering Drive, Madison, Wisconsin 53706; and †Departamento de Matemática Aplicada, Escuela Superior de Informática, Universidad Compl...

This paper describes an efficient urban outdoor and indoor wave propagation model that supports receiver performance and coverage analyses as well as system effectiveness analyses within urban canyon environments described in the Compact Terrain Database (CTDB) format. The model has been used to support Joint MEASURE based analyses of GPS III performance/coverage within a typical urban environm...

A hybrid method for analysis of electromagnetic propagation in large unbounded wave structures is presented. This method is a combination of Gaussian Beam Tracing (GBT), Gabor Expansion and the Finite Difference Time Domain method (FDTD). The input field is first expanded into a sum of Gaussian Beams (GBs) using the Gabor Expansion. The resultant GBs are launched inside the system and traced us...

Both experiments and finite difference time domain (FDTD) calculations show that infrared (IR) absorption spectroscopy and IR transmission resonances of metal films with arrays of subwavelength holes (meshes) are more sensitive to material in the holes of the mesh than to material on the front or back surfaces of the mesh. IR extinction spectra of isolated, individual latex (polystyrene) sphere...