Study of transient phenomena with feature selective validation method

In recent years, computational electromagnetism has had a great development thanks to the computational systems speed increase and their cost reduction. With those improvements the mathematical algorithms are able to work properly with more practical EMC issues. The problem that arises many times is to become condent with the results, in other words, to be able to quantitatively validate the results of the numerical simulation. In this paper we present a method to evaluate the diference between results obtained by visual expert opinion and those obtained from the FSV method.Peer ReviewedPostprint (published version

Transient perturbation analysis in digital radio

This paper presents a new simulation methodology to study the effect of radiated transient disturbances on digital communication systems. The procedure is divided in two stages. In the first one, FDTD numerical simulation is used to determine the transient levels coupled to the antennas. In the second stage, these levels are analyzed by means of a signal processing simulation software to determine the degradation caused in the system. The procedure is applied to a DAB system in car when a radiated interference is generated by a transient in a vehicle cable. The results show that the amplitude of the radiated transient coupled signal is a key parameter, but it is also essential to take into account other parameters such as burst duration and frequency.Postprint (published version

Factors influencing the successful validation of transient phenomenon modelling

An increased requirement for validation of computational electromagnetic simulation and modelling through the publication of IEEE Standard 1597.1 brings to light some interesting issues surrounding the validation of transients. The structure of a transient event has three particular regions of interest that can have an influence on the results, of which only two are generally well defined. These are the initial quiescent phase from t = 0 to the transient event; the transient event itself up to the point where the energy has fallen to a predefined limit, and the post-transient phase where residual energy is still present in the system. This latter region is generally ill-defined and changes the way that a validation comparison should be made, from, for example a frequency domain coupling study where the region of interest is usually well defined. This study looks at the influence of the three regions on the validation results and suggests how the Feature Selective Validation (FSV) method can be applied in transient studies.Peer ReviewedPostprint (published version

Characterization of EMI filters based on metamaterials

This paper analyzes the behavior of EMI filters based on metamaterials. The filters are developed by means of sub-wavelength resonators and designed to have notch-type attenuation in the 2.45 GHz band. Two types of filters based on SRR and CSRR rings are presented. The simulated responses by MoM and FDTD are compared with the measurement data obtained from the developed prototypes.Peer ReviewedPostprint (published version

Numerical validation methods

In the last years, numerical simulation has seen a great development thanks to costs reduction and speed increases of the computational systems. With these improvements, the mathematical algorithms are able to work properly with more realistic problems. Nowadays, the solution of a problem using numerical simulation is not just finding a result, but also to ensure the quality. However, can we say that the model results are correct regarding the behaviour of the system? In other words, how could we quantify the similarity between reality and simulations? To answer these questions, it is necessary to establish a validation criterion that allows an objective quantification of the difference between the results and the reality. Another way to say this is, how “true” our results are. In the case of numerical methods, the main objective is to replicate as closely as possible the behaviour of the "real" world through numbers. Normally, the results of the numerical methods are expressed in terms of graphics, pictures, etc. These results represent the view of reality that the chosen method provides. In order to affirm that the result of a numerical solution is fully consistent with the reality, it must be satisfied that: a. The mathematical model must incorporate all aspects of the real world. b. The numerical method has to solve exactly the equations of the mathematical modelling. The problem starts with these two conditions that guarantee the "truth" of the results, since none of them are fully accomplished and it must be admitted that the numerical prediction never completely matches the "real" world behaviour. Then you can only be sure that the numerical solution is a good approximation of the reality. Now, new questions arise: How much does the result obtained by a numerical method resemble the reality? How can we objectively quantify this similarity? The answers to these questions are those that give rise to the validation methods.Peer Reviewe

Study of transient phenomena with feature selective validation method

In recent years, computational electromagnetism has had a great development thanks to the computational systems speed increase and their cost reduction. With those improvements the mathematical algorithms are able to work properly with more practical EMC issues. The problem that arises many times is to become condent with the results, in other words, to be able to quantitatively validate the results of the numerical simulation. In this paper we present a method to evaluate the diference between results obtained by visual expert opinion and those obtained from the FSV method.Peer Reviewe

Broadband antenna FDTD modeling for EMC test

This paper describes the modeling and analysis to modeling EMC immunity test by means of computer simulation with Finite Difference Time Domain (FDTD) method. To ensure the integrity of the results the log-periodic antenna was simulated separately and then included in a more complex model. Despite the many limitations of both the numerical models and the measurements, the models provide a satisfactory representation of the electrical field radiated by the antenna

Study of transient phenomena with feature selective validation method

In recent years, computational electromagnetism has had a great development thanks to the computational systems speed increase and their cost reduction. With those improvements the mathematical algorithms are able to work properly with more practical EMC issues. The problem that arises many times is to become condent with the results, in other words, to be able to quantitatively validate the results of the numerical simulation. In this paper we present a method to evaluate the diference between results obtained by visual expert opinion and those obtained from the FSV method.Peer Reviewe

Examination of ecological and economic aspects of welding processes

Translated from Russian (Report of the E O Paton Electric Welding Institute, Kiev, 1998)Available from British Library Document Supply Centre-DSC:9023.190(VR-Trans-9316)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Aplicación del método Feature Selective Validation al análisis de fenómenos transitorios

In recent years, there has been an increased requirement for validation of computer simulation and electromagnetic modelling. During the development and implementation of new simulation methods it is useful, if not essential, to verify the appropriate modelling and simulation by comparison with appropriate measures. However, few studies are using an objective validation method to quantify the quality of their results. This paper presents the comparison between measurements and simulations using the W-FSV validation method. Specifically, the study used the validation method for analyzing and quantifying the quality of the mesh in the method of finite differences in time domain when a transient disturbance appears.Peer Reviewe