Mrinal Mishra

Monte Carlo Integration Technique for the Analysis of Electromagnetic Scattering from Conducting Surfaces

A new numerical method is proposed for the analysis of electromagnetic scattering from conducting surfaces. The method involves Monte Carlo integration technique in the Method of Moments solution of the Electric Field Integral Equation for determining the unknown induced current distribution on the surface of the scatterers. The unknown current distribution is represented in terms of a modified entire domain polynomial basis functions satisfying the appropriate edge conditions and symmetry conditions of the problem. This leads to very small order of the Method of Moments matrix as compared to the conventional sub-domain basis functions. The accuracy and the effectiveness of the method are demonstrated in three cases of scattering from conducting circular disks and results are compared with the solutions using conventional sub-domain basis functions. While the sub domain analysis is incapable of handling large domain problems, the proposed method overcomes this limitation. It is also observed that the proposed method is superior to conventional sub-domain method in dealing with singularity problem of the integral equation easily and efficiently.

Study of a Fluorescent Tube as Plasma Antenna.

The present paper is a work on fluorescent tube performing the function of a monopole plasma antenna. In the construction, the needed power supply to the fluorescent tube is controlled by an IC 555 timer. In the experiments the supply frequency varies from 25Hz to 200Hz. By using a vector network analyzer it is shown that the persistence of plasma developed inside the tube persists for longer duration with increase in supply frequency. It is also found that the stability of resonant frequency increases with the increase in frequency of the AC power supply measured up to 200 Hz. Result shows that the effective part of a fluorescent tube functioning as Monopole plasma antenna is about 60% of the total length of the tube.

Application of Quasi Monte Carlo Integration Technique in Efficient Capacitance Computation

A new integration technique based on use of Quasi Monte Carlo Integration (QMCI) technique is proposed for Method of Moments (MoM) solution of Integral equation for capacitance computation. The integral equation for unknown charge distribution over the capacitors is formulated. The solutions are obtained by MoM using the QMCI technique. It is observed that the proposed method is not only capable of dealing with the problem of singularity encountered in the Integral Equation e-ciently but also provides accurate computation of the capacitances of parallel plate, cylindrical and spherical capacitors.

Application of Quasi Monte Carlo Integration Technique in EM Scattering from Finite Cylinders

In this work, a Quasi Monte Carlo (QMC) Integration Technique using Halton Sequence is proposed for the Electric Field Integral Equation (EFIE) in the Method of Moments (MoM) solution for scattering problems. It is found that the Halton Sequence used in QMC integration scheme is capable of handling the singularity issue in the EFIE automatically and at the same time provides solution to the scattering problems very easily. Finally the proposed technique is applied to solve the scattering problem from a finite cylinder employing the entire domain basis function expansions. The results obtained show a good agreement between the proposed and conventional technique.

Monte Carlo integration Technique in Method of Moments solution of Integral equation

A new integration technique based on use of Monte Carlo integration is proposed for Method of Moments solution of Integral equation. As an example numerical analysis is carried out for the solution of the integral equation for unknown charge distribution on metallic structures. This employs a new set of entire domain basis functions. It is observed that the proposed method is not only capable of dealing with the problem of singularity efficiently but also provides accurate and fast computation of the unknown charge distribution on the surface of the metallic structures.

Lightning alarm system using stochastic modelling

It is true that such a long-range forecasting of lightning is not possible, the reason being the abrupt high value of the parameters at the time of lightning strike as compared to other weather conditions. But still a system that will predict the occurrence of lightning over few minutes or few hours will be beneficial for protection of lives and equipments. In this work, atmospheric electric field data are used for devising an alarm system for lightning. With the help of Markov chain stochastic modelling of the electric field data, probabilities of a lightning strike are calculated.

A New Algorithm for Method of Moments Solution of Static Charge Distribution

A new integration algorithm based on use of Quasi Monte Carlo Integration (QMCI) technique is proposed for Method of Moments (MoM) solution of Integral equations. As an example, solution of the integral equation for unknown charge distribution on metallic structures is obtained. It is observed that the proposed method is not only capable of dealing with the problem of singularity efficiently but also provides accurate computation of the static charge distribution on thin metallic rods.