Matthew N. O. Sadiku

Numerical Techniques in Electromagnetics, Second Edition

Numerical Techniques in Electromagnetics is designed to show the reader how to pose, numerically analyze, and solve electromagnetic (EM) problems. It gives them the ability to expand their problem-solving skills using a variety of available numerical methods. Topics covered include fundamental concepts in EM; numerical methods; finite difference methods; variational methods, including moment methods and finite element methods; transmission-line matrix or modeling (TLM); and Monte Carlo methods. The simplicity of presentation of topics throughout the book makes this an ideal text for teaching or self-study by senior undergraduates, graduate students, and practicing engineers.

A further introduction to finite element analysis of electromagnetic problems

An elementary tutorial introduction in finite-element numerical analysis is presented. The finite-element method is applied to Laplacian electrostatic field problems. Suggestions are offered on how the basic concepts developed can be extended to finite-element analysis of problems involving Poissons or the wave equation. A step-by-step procedure for coding the numerical method is presented; a useful, working FORTRAN program is also included. >

Refractive index of snow at microwave frequencies

A systematic procedure for calculating the refractive index of snow at microwave frequencies is presented. The refractive index of snow at 0°C was calculated for different snow types (classified in terms of snow wetness as dry, most, wet, and watery) and microwave frequencies. For the sake of completeness, the refractive indices of water and ice were also calculated for the same frequencies.

Software-defined radio: a brief overview

This paper overviews the software-defined radio (SDR), also called software radio (SR), refers to wireless communication in which the transmitter modulation is generated or defined by a computer. The receiver then also uses a computer to recover the signal intelligence. SDR is an enabling technology that is useful in a wide range of areas within wireless systems. The primary goal of SDR is to replace as many analog components and hardwired digital VLSI devices of the transceiver as possible with programmable devices. This technology is receiving enormous recognition and generating widespread interest in the telecommunication industry. The SDR Forum is an international, nonprofit organization that includes members from academia, the military, vendors, wireless service providers, and regulatory bodies. SDR has been described as the cornerstone in the evolution of GSM.

Integrated services digital network

Publisher Summary This chapter reviews the concept of an integrated services digital network or ISDN. Now, integrating voice and data communications is also motivated by advances in computer and communications technology. Also, The ISDN is based on the well-known Open Systems Interconnection (OSI) reference model of the International Organization for Standardization, which defines seven-layer architecture for communications functions. ISDN is a result of a dozen of years of effort by communications experts the world over, and is an international push to upgrade business and home communications. ISDN is the final step in which digital reaches the customer premises, first on copper and later on fiber optical wires. ISDN is the first network-based standard for simultaneous integrated voice, data, and image signal transmission. ISDN is not itself a service but rather an interface to existing and future services. ISDN promotes innovation and the convergence of information technology and telecommunications in open network structures. ISDN is mutually beneficial to the network operator, service provider, the equipment manufacturer, and the end user. ISDN is the replacement of the analog plant using standardized access to permit the user to transmit voice and/or data over a worldwide network to any other user on a demand basis. Subsequently, as an all-digital network, ISDN offers increased clarity, accuracy, and speed; ISDN allows users to achieve convenience, flexibility, and economy.

Monte Carlo methods in an introductory electromagnetic course

Although the pedagogical value of introducing numerical methods such as finite-element methods, finite-difference methods, and moment methods in an introductory electromagnetics (EM) course has been recognized, no similar attempt has been made to introduce Monte Carlo methods. An attempt is made to fill this gap by presenting Monte Carlo procedures in simple terms that can be presented in an introductory EM course. The statistical method is specifically applied to potential problems. Typical illustrative examples are provided. >

Solution of Dirichlet problems by the Exodus method

Applying the Exodus method to Dirichlet problems in rectangular and axisymmetric solution regions is proposed. The stochastic technique is illustrated with specific practical applications to the solution of Laplaces equation. Although the method is probabilistic in its approach, it is not subject to randomness as are the other Monte Carlo techniques because it does not involve the use of a pseudo-random generation subroutine. The method provides a more accurate solution in less amount of time compared with the fixed random walk. It is also found that the accuracy of the Exodus method is comparable to that of the finite difference method. >

Next generation networks

The forces for high speed, high capacity data services are driving the next generation network architecture toward a packet network. These next generation networks are basically of two types: wired networks and wireless networks. Changes in network services, technology and regulation are creating a golden era of network innovation. Much is certain in this evolution. For instance, the networks will have a shared, packet-based, optical-core network using dense wavelength division multiplexing (DWDM) optical transport with optical add/drop and multiplexing. Wireless communications is expected to be a major driver for growth in the telecommunications industry over the next decade. It will become a cornerstone of the information society. Future networks (both wireless and wireline) of the type described here will pave the way for an environment in which information will be made more portable, personal and affordable. They will achieve the ultimate goal of communications-communications from anywhere to anywhere-clear as a bell.

A Simple Introduction to the Method of Lines

The method of lines (MOL), a semianalytical procedure, is well known to experts in computational techniques in electromagnetics. The range of applications of the method has increased dramatically in the past few years; nevertheless, there is no introductory paper to initiate a beginner to the method. This paper illustrates the application of the MOL to solve Laplaces equation in rectangular and cylindrical coordinates. Two numerical examples are used to verify the procedure. The results obtained compare well with analytical solutions.

Monte Carlo Methods for Electromagnetics

Introduction Why Monte Carlo? Historical Background Applications of MCMs Review of Electromagnetic Theory Probability and Statistics Generation of Random Numbers Statistical Tests of Pseudorandom Numbers Generation of Random Variates Generation of Continuous Random Variates Evaluation of Error Summary Finite Difference Method Finite Differences Finite Differencing of Parabolic PDEs Finite Differencing of Hyperbolic PDEs Finite Differencing of Elliptic PDEs Accuracy and Stability of Finite Difference Solutions Maxwells Equations Summary Fixed Random Walk Introduction Solution of Laplaces Equation Solution of Poissons Equation Solution of Axisymmetric Problems Summary Floating Random Walk Introduction Rectangular Solution Regions Axisymmetric Solution Regions Summary The Exodus Method Solution of Laplaces Equation Solution of Poissons Equation Summary Neumann Problems Governing Equations Triangular Mesh Method Computing Procedure Summary Whole Field Computation Introduction Regular Monte Carlo Method Absorbing Markov Chains Summary Time-Varying Problems Introduction Diffusion Equation Rectangular Solution Region Cylindrical Solution Region Summary Scattering from Random Rough Surfaces Introduction Scattering of by 1-D Random Rough Surfaces Scattering of by 2-D Random Rough Surfaces Summary Multidimensional Integration Introduction Crude Monte Carlo Integration Monte Carlo Integration with Antithetic Variates Improper Integrals Summary References and Problems appear at the end of each chapter.