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The CGG-FFT method: Application of signal processing techniques to electromagnetics
Journal
ofAfmo.phmc
Pergamon
and
Solar-Terrrsrrral
Physrcs, Punted
Vol. 10 Great
59. No 5, pp. 597-599, 1997 ,A: 1997 Elsev~er Science Ltd Britam All rmhts reserved 13646X26/97 il7.00+0.00
Book reviews circuits with sources is not treated here but in the eleventh chapter, whose general purpose is multilayered substrates for the planar structures. The planar circuits with sources are very useful for engineers and researchers in the microwave domain, The simulation permits us to compute the transmission and reflection coefficient for any planar two port. The sixth chapter is devoted to diffraction problems by three dimensional bodies of any shape. The elements for discretization are now cubic and the process is close to that of the preceding chapter. Results about metallic and dielectric cubes and spheres are given. The seventh chapter treats the coupled integral equations in planar circuits with application to the Vivaldi antenna. As for the eleventh chapter the place of this chapter would be better in a part devoted to planar circuits. The remainder of the work is devoted to periodic structures. Considered here are: planar circuits drawn on bodies of revolution (an interesting and original study), biperiodic circuits on stratified substrates and an analysis of three dimensional bodies which are periodic in one dimension. The reader interested by the treatment of the above mentioned problems will find in this book the main theory, bibliographic references of recent works and numerous applications. Otherwise, one can regret the lack of synthesis and physical explanations. The abuse of abbreviations (even in the title of the book!) sometimes gives the text the appearance of a coded message. These points are not of major importance and will not put off the scientist who is concerned with integral methods in the electromagnetic diffraction. H. Baudrand ENSEEIT, Toulouse
The CGG-FFT Method: Application of Signal Processing Techniques to Electromagnetics, Catedra M. F., Torres R. F., Basterrechea J., Gago E., 1995, 361 pp. Artech House Books, Boston, London, E76.00, ISBN O-89006-634-5. This book whose title is a little mysterious to the layman’s mind is in fact a review of integral methods used in problems of electromagnetic wave diffraction. The interest of this book is to mix numerical and electromagnetic aspects, contrary to many other books. Each chapter (there are twelve in the book) is built following the same model: introduction, development of the theory concerned, examples and some concluding remarks. The object of this book is not to give at each stage the essential demonstrations, but rather to give practical and useful methods and to comment on published works. The reader will appreciate the numerous bibliographic references (about thirty per chapter). The researcher who wants to begin work in the field of electromagnetic diffraction will be helped by this book which permits him/her to know quickly the present level of the solutions. After a short introductory chapter, the authors devote the following chapter to the Fourier transform, both continuous and discrete. Six books are given in the references to show the importance of Fourier transforms in electromagnetism. Some tables give the transform or the most useful functions. Immediately after, a relatively simple application is given. This concerns one dimensional static problems. The authors reach in the third chapter the periodic structures which will be abundantly developed in the following. The periodicity of the structures gives discrete transforms; therefore, these are easily solved by the methods proposed in this book. The advance in complexity leads the authors to develop the descent method. Indeed, the integral methods explained in the preceding chapter lead us to solve linear equations characterized by a full matrix. The conjugate gradient method is well adapted for most of the cases. The curves showing the comparison of convergence between different methods are very interesting and useful. The next chapters are devoted to some electromagnetic problems graded in growing difficulty. In most cases, a short introduction poses the theoretical problem; afterwards a choice of discretization process is described and numerical results are presented. They are compared with published or experimental results. An original interest of these studies is to present the evolution of the error with the number of iterations. The reader wanting to be initiated into the numerical treatment of a given problem will find here some very interesting information and, as in the first part of this book, pertinent bibliographic references. Successively, the authors treat the following problems: in the fifth chapter. the one dimensional and two dimensional planar circuits are solved with Green’s functions in the real domain and spectral domain (for the two dimensional circuits). This last choice justifies the use of fast Fourier transform. The current density is used as a trial function. The given examples describe some resonant patches, rectangular, circular and of any shape. The important problem of planar
Spotlight Synthetic Aperture Radar: Signal Processing Algorithms, Carrara W. G., Goodman R. S. and Majewski R. M., 1995, 554 pp. Artech House, Boston, London, f63. hb, ISBN o-89006-728-7. This book is a detailed description of processing schemes for spotlight synthetic aperture radar (SAR), with particular emphasis given to the polar format algorithm. The core of the book is an exhaustive discussion of the signal phase equation for a point scatterer and its use in producing high fidelity radar images. A comprehensive treatment of the processing chain is given, including both its SAR-specific components, such as autofocus, and more generally applicable operations, such as interpolation schemes. The approximations used by the different algorithms and error sources in the phase equation are dealt with in great detail, together with indications of their effects on image quality. Comparison of algorithms in terms of accuracy and complexity is also provided. The systems dealt with are primarily airborne SARs or ground-based inverse SAR facilities, with an implicit bias towards the needs of military reconnaissance (target detection and identification). Space-based radar is barely mentioned and civilian applications receive little attention 597
ofAfmo.phmc
Pergamon
and
Solar-Terrrsrrral
Physrcs, Punted
Vol. 10 Great
59. No 5, pp. 597-599, 1997 ,A: 1997 Elsev~er Science Ltd Britam All rmhts reserved 13646X26/97 il7.00+0.00
Book reviews circuits with sources is not treated here but in the eleventh chapter, whose general purpose is multilayered substrates for the planar structures. The planar circuits with sources are very useful for engineers and researchers in the microwave domain, The simulation permits us to compute the transmission and reflection coefficient for any planar two port. The sixth chapter is devoted to diffraction problems by three dimensional bodies of any shape. The elements for discretization are now cubic and the process is close to that of the preceding chapter. Results about metallic and dielectric cubes and spheres are given. The seventh chapter treats the coupled integral equations in planar circuits with application to the Vivaldi antenna. As for the eleventh chapter the place of this chapter would be better in a part devoted to planar circuits. The remainder of the work is devoted to periodic structures. Considered here are: planar circuits drawn on bodies of revolution (an interesting and original study), biperiodic circuits on stratified substrates and an analysis of three dimensional bodies which are periodic in one dimension. The reader interested by the treatment of the above mentioned problems will find in this book the main theory, bibliographic references of recent works and numerous applications. Otherwise, one can regret the lack of synthesis and physical explanations. The abuse of abbreviations (even in the title of the book!) sometimes gives the text the appearance of a coded message. These points are not of major importance and will not put off the scientist who is concerned with integral methods in the electromagnetic diffraction. H. Baudrand ENSEEIT, Toulouse
The CGG-FFT Method: Application of Signal Processing Techniques to Electromagnetics, Catedra M. F., Torres R. F., Basterrechea J., Gago E., 1995, 361 pp. Artech House Books, Boston, London, E76.00, ISBN O-89006-634-5. This book whose title is a little mysterious to the layman’s mind is in fact a review of integral methods used in problems of electromagnetic wave diffraction. The interest of this book is to mix numerical and electromagnetic aspects, contrary to many other books. Each chapter (there are twelve in the book) is built following the same model: introduction, development of the theory concerned, examples and some concluding remarks. The object of this book is not to give at each stage the essential demonstrations, but rather to give practical and useful methods and to comment on published works. The reader will appreciate the numerous bibliographic references (about thirty per chapter). The researcher who wants to begin work in the field of electromagnetic diffraction will be helped by this book which permits him/her to know quickly the present level of the solutions. After a short introductory chapter, the authors devote the following chapter to the Fourier transform, both continuous and discrete. Six books are given in the references to show the importance of Fourier transforms in electromagnetism. Some tables give the transform or the most useful functions. Immediately after, a relatively simple application is given. This concerns one dimensional static problems. The authors reach in the third chapter the periodic structures which will be abundantly developed in the following. The periodicity of the structures gives discrete transforms; therefore, these are easily solved by the methods proposed in this book. The advance in complexity leads the authors to develop the descent method. Indeed, the integral methods explained in the preceding chapter lead us to solve linear equations characterized by a full matrix. The conjugate gradient method is well adapted for most of the cases. The curves showing the comparison of convergence between different methods are very interesting and useful. The next chapters are devoted to some electromagnetic problems graded in growing difficulty. In most cases, a short introduction poses the theoretical problem; afterwards a choice of discretization process is described and numerical results are presented. They are compared with published or experimental results. An original interest of these studies is to present the evolution of the error with the number of iterations. The reader wanting to be initiated into the numerical treatment of a given problem will find here some very interesting information and, as in the first part of this book, pertinent bibliographic references. Successively, the authors treat the following problems: in the fifth chapter. the one dimensional and two dimensional planar circuits are solved with Green’s functions in the real domain and spectral domain (for the two dimensional circuits). This last choice justifies the use of fast Fourier transform. The current density is used as a trial function. The given examples describe some resonant patches, rectangular, circular and of any shape. The important problem of planar
Spotlight Synthetic Aperture Radar: Signal Processing Algorithms, Carrara W. G., Goodman R. S. and Majewski R. M., 1995, 554 pp. Artech House, Boston, London, f63. hb, ISBN o-89006-728-7. This book is a detailed description of processing schemes for spotlight synthetic aperture radar (SAR), with particular emphasis given to the polar format algorithm. The core of the book is an exhaustive discussion of the signal phase equation for a point scatterer and its use in producing high fidelity radar images. A comprehensive treatment of the processing chain is given, including both its SAR-specific components, such as autofocus, and more generally applicable operations, such as interpolation schemes. The approximations used by the different algorithms and error sources in the phase equation are dealt with in great detail, together with indications of their effects on image quality. Comparison of algorithms in terms of accuracy and complexity is also provided. The systems dealt with are primarily airborne SARs or ground-based inverse SAR facilities, with an implicit bias towards the needs of military reconnaissance (target detection and identification). Space-based radar is barely mentioned and civilian applications receive little attention 597