Yoon-Mi Park

Electromagnetic Field Penetration Analysis of a Rectangular Aperture-Backed Cavity Based on Combination of Electromagnetic Topology and Mode Matching

Abstract In this article, a new method that is based on a combination of electromagnetic topology and mode matching is proposed for the analysis of electromagnetic field coupling. The proposed method can accurately solve the electromagnetic field coupling in a complex system with a short computation time and reduced memory. A wire within an aperture-backed cavity model was analyzed, and the electric field intensity in the cavity and the induced surface current on the wire were computed. The results were compared with finite difference time domain results and confirmed the electromagnetic field coupling is influenced by the geometry of the enclosure.

Analysis of electromagnetic field penetration through apertures based on electromagnetic topology

In this paper, a method for computation of electromagnetic field penetration is proposed. A cavity model with an aperture was analyzed using electromagnetic topology (EMT) based on Baum-Liu-Tesche (BLT) equation. The rectangular cavity Greendasias function is used to determine the fields in the cavity and the free space Greendasias function is used to determine the scattered fields due to the aperture in the free space. The equations are substituted in the BLT equation and determine electromagnetic field penetration. The results from topological modeling are in agreement with simulation results. In this research, field coupling phenomenon between external fields and a wire in the cavity is studied, thus further research is required relating EMC analysis to the integrated circuit in the cavity using EMT.

Numerical Technique for Nonlinear Circuit Analysis Using the Method of Electromagnetic Topology Based on Harmonic Balance

Abstract The purpose of this study is to propose an improved numerical technique for large and nonlinear circuit analysis using electromagnetic topology based on harmonic balance. Harmonic balance has been used for the analysis of a nonlinear system; however, it needs a large number of variables that must be optimized, and this makes the method impractical for large systems. Electromagnetic topology is proper for a large system using volume decomposition; the method has been studied for linear analysis [Park, Y.-M., Y. Lee, Y.-S. Chung, C. Cheon, & H.-K. Jung, 2009. Electromagnetic field penetration analysis of a rectangular aperture-backed cavity based on combination of electromagnetic topology and mode matching. Electromagnetics 29:447–462], but the method for a nonlinear system has never been studied. Therefore, a technique for combining electromagnetic topology and harmonic balance to analyze large and nonlinear systems is proposed. In the proposed method, electromagnetic topology and harmonic balance communicate in real time; the updated voltage through harmonic balance are applied to electromagnetic topology as boundary conditions, and the results of the electromagnetic topology are used for computing linear currents in the harmonic balance until errors are negligibly small. Compared with conventional methods for analyzing large and nonlinear systems, the merits of the proposed method are fast computation time, reduced memory requirements, and compatibility with other simulation and experiment techniques. A voltage doubler model was analyzed using the proposed method at 100 and 230 MHz. The results of the analysis are compared with experimental results, and the validity of the method was confirmed.

Electromagnetic Topology combined with Mode Matching for the electromagnetic field penetration analysis of an aperture backed cavity

In this paper, a new method, based on the combination of Electromagnetic Topology (EMT) and Mode Matching (MM), is proposed for the analysis of the electromagnetic field coupling phenomena from an external field to an inner electric system. The proposed method can solve the electromagnetic field coupling in a complex system accurately and requires a short computation time and reduced memory. To verify the validity of this method, an aperture backed cavity model was analyzed and the electric field intensity in the cavity and the induced surface current on the wire were computed. The results were compared with FDTD results.

A Study of Error Estimation and Adaptive Junction Subdivision for Electromagnetic Topology

Electromagnetic topology simplifies a complex analysis area in accordance with electromagnetic coupling. And then electromagnetic topology divides the simplified continuous area into sub-areas and analyzes electromagnetic problems at the sub-areas. Therefore electromagnetic topology has a merit to analyze the electromagnetic coupling in large and complex systems, however simplified modeling technique can generate large errors. In this paper, power balance method is used to estimate errors and subdivide junctions in the electromagnetic topology. The method is applied to analyze conducted and radiated electromagnetic coupling in two kinds of cavity models. Improvement of accuracy was accomplished in accordance with junction subdivision. Moreover we could save computation time and memory comparing with FDTD results.

The investigation of measurement method for HPM radiation to the analog switch chip

In this paper we suggest a special measurement system using an optical transformation when an analog switch chip is exposed by an external High Power Microwave(HPM). The proposed measurement system can compare a normal operation with a malfunction of the chip, analyzed signals at each pin of the chip when the HPM radiates to the chip. To analyze accurately the operation of the chip proposed measurement system uses an optical communication method. An electrical signal of the chip is modulated to an optical signal by a laser diode(LD) within the range of the HPM. After that, the modulated optical signal is demodulated to the electrical signal by a photo diode(PD) beyond the range of the HPM and then signal is measured. Because this system has no interference between frequency of microwaves and optical waves, an accurate analysis is possible.

Susceptibility analysis of a nonlinear system using hybrid method of Electromagnetic Topology and Harmonic Balance

This paper suggests an improved Electromagnetic Topology (EMT) method, based on Harmonic Balance (HB), to analyze electromagnetic field coupling to nonlinear system. In the proposed method, EMT and HB communicate in real-time. The voltage results from the HB are imposed on the EMT as boundary conditions and the voltage results from EMT are used for computing linear and nonlinear currents in the HB. Voltage responses on a voltage doubler in a cavity were calculated. Measurement and simulation results agreed.

Investigation of the nonlinear circuit analysis by electromagnetic topology based on harmonic balance

Over the past few decades, several studies have been made on the nonlinear analysis of electronic circuits. In microwave and RF circuits, components such as limiting amplifiers, oscillators, doublers, and mixers rely on device nonlinearity for proper operation. The problem of analyzing and designing nonlinear circuits is usually more complicated than it is for linear circuits. Therefore, this paper is intended as a proposal of an improved numerical technique for large and nonlinear circuit analysis using electromagnetic topology (EMT) based on harmonic balance (HB). HB has been used for the analysis of nonlinear system. However the HB needs the large number of variables that must be optimized, and this makes the method impractical for large systems. On the other hand, EMT is an effective method for analyzing large systems using volume decomposition. The EMT has been studied for linear analysis [1], but very few attempts have been made at the nonlinear circuit analysis. Therefore, a combination method for EMT and HB is proposed. In the proposed method, EMT and HB communicate real-time: the updated voltage result by the HB are excited to the EMT as sources, and the computation results by the EMT are substituted for computing linear and nonlinear current in the HB until errors are negligibly small. The merits of the proposed method are fast computation time, reduced memory requirements, and compatibility with other simulation and experiment in comparison with conventional methods. To verify the proposed method, the analysis of a voltage doubler circuit was performed at 500MHz. The analysis results were compared with experimental results, and the results indicated a validity of the method.

Investigation of a Method for RF Circuits Analysis Based on Electromagnetic Topology

In this paper, electromagnetic topology (EMT) was used to analyze the electromagnetic compatibility (EMC) of RF circuits including passive and active components. It is difficult to obtain usable results for problems relating to electromagnetic coupling in complex systems when using conventional numerical or experimental methods. Thus it is necessary to find a new methodology for analyzing EMC problems in complicated electromagnetic environments. In order to consider the nonlinear characteristics of active components, a SPICE diode model was used. A power detector circuit and the receiver circuit of a radio control (RC) car were analyzed and experimented in order to verify the validity of this method.

Analysis of printed circuit boards including active components based on electromagnetic topology

It has been shown that the circuit with the active components is analyzed by using the EMT based on the BLT equation. In order to consider the nonlinear behavior of the diode, the SPICE diode model is applied to the EMT method. The results from the topological modeling are in agreement with the simulation and measured results. In this research, the EMT is based on the circuit simulation, thus it is needed to combine with full-wave simulation for more accuracy.