Yusuke Kusama

Toyo University · Department of Electrical and Electronic Engineering

In this research, a compact and broadband microstrip line quarter-wavelength open circuited stub, which is the core of the band-stop filter, is studied from the viewpoint of the characteristic impedance ratio between the main transmission line and the stub line. Furthermore, a circuit pattern in which an inductive diaphragm is inserted at the stub...

Many studies on the conductor loss of the copper-clad dielectric substrate have already been reported. And a method of obtaining frequency characteristics of the conductivity from the measured value by applying the concept of effective conductivity is adopted. In this report, the decrease rate of the signal line cross-sectional area due to the skin...

The use of a triple combination of theory, simulation, and lab exercise is most commonly used to promote better student understanding of microwave fundamentals. As part of the RF engineers training education program, an advanced experiments program has been developed in which students can experience successive trial and error procedures including d...

In this program, 2-D FDTD source code was introduced with references for beginners so that a progressive series of simulations including model creation, source code modification, compilation, results output on display while introducing some of the specific analysis cases such as wire and reflector antenna, waveguide, diffraction, scattering, shield...

When the FDTD method is applied to the analysis of a multimode waveguide, a problem is the treatment of the absorbing boundary corresponding to the matching at the termination. In the present study, the electromagnetic field in the cross section of the waveguide one cell inward from the termination is expressed as a linear combination of the eigenm...

Assuming a choke groove depth of half the present value, the FD-TD method is used to obtain a value for the effectiveness of shielding against leakage waves that is very close to the actual value, including higher modes. To reduce computation time, the optimum dimension is first calculated for a TEM mode wave incident on a choke groove with a two-d...

By means of the three-dimensional FDTD, the shield effect is studied for a sheet-type lossy material inserted in the gap between a microwave oven body and its door as a way to suppress the microwave leakage in place of the generally used choke structure. Specifically, the shield effect versus the inserted length of the lossy material and the gap is...

This paper focuses on the choke structure, which is generally used in suppressing the leakage wave from the door gap of microwave ovens. A choke structure which simulates the interdigital periodic choke structure for mass-produced microwave ovens is considered, and the shielding effect is examined by the FDTD method for leaky waves (hybrid waves) i...

In this paper, the shielding effects for various door seals of a microwave oven are discussed. The FDTD method is adopted in the numerical calculations. It is shown here that there are optimum combinations of part sizes and structures by which the high shielding effect is obtained. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 19: 333–3...