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Parallel coupled lines and directional couplers
Book
Reviews
LOGIC DESIGN OF DIGITAL SYSTEMS, by Donald L. Dietmeyer. 800 pages, diagrams, 6 x 9 in. Boston, Mass., Allyn & Bacon, 1971 and 1972. Due to the growing importance of automated design techniques in digital system design (1, 2), this book, with its emphasis on computer-implementable algorithmic approaches to logic design, is a useful addition to the field. The book covers a wide range of topics from the basic to the advanced. Chapter 1, which covers number systems and some of the binary codes, provides an adequate background for the other chapters. Then set theory, Boolean algebra, switching functions and their representation are introduced, along with Minimization using simple examples. Karnaugh maps and Quine-McCluskey algorithm is described and illustrated by practical design examples. Chapter 3 is concerned with algorithmic synthesis of combinational networks. Apart from developing the theory and algorithms, FORTRAN programs implementing many of the algorithms are also given. These programs can be used if the operators defined are implemented on a computer as FORTRAN subroutines. Next is an introduction to the analysis and synthesis of synchronous sequential networks. Hazards in combinational networks and analysis and synthesis of asynchronous sequential networks are covered in Chap. 5. A good overall introduction to digital system architecture and design is given. A simple digital computer is described and used a.s a vehicle to illustrate the theory, thus making the concepts easier to understand. A section on microprogramming is included. In going through the book in detail, this reviewer noted that very little background is needed to study the book as it is selfcontained. It is clearly written, easy to follow, and contains many practical examples. A large number of student exercise problems (with answers to many of them) and a comprehensive list of references are included at the end of each
chapter. A digital-system design language (3), useful for describing large digital networks, is described and used throughout,. The book does not deal with redundancy techniques used for increasing reliability, except for information redundancy. Also, there is only a brief treatment on threshold devices. However, these omissions detract from the completeness of the book in only a minor way. Overall, this book is extremely wellsuited for use in the classroom. It is also excellent as a text for self-study and as a reference. RAMACHENDRA P. BATNI Department of Electrical Engineering University of Wisconsin Madison, Wisconsin References
(1) Computer,
Vol. 5, No. 3, May/June 1972. (2) M. A. Breuer (Ed.), “Design Automation of Digital Systems: Theory and Techniques. Volume I, Hardware”, Prentice-Hall, Englewood Cliffs, N.J., 1972. (3) J. R. Duley and D. L. Dietmeyer, “A Digital System Design Language (DDL)“, IEEE Trans. Computers, Vol. C-17, pp. 850-861, Sept. 1968.
PARALLEL COUPLED LINES AND DIRECTIONALCOUPLERS,edited by Leo Young. 274 pages, diagrams. Dedham, Mass., 1972. Price $11.95 Artech House, (approx. $4.25). This book consists of a collection of 30 papers on the subject of electromagnetic coupling between a pair of transmission lines propagating in TEMtype modes. The topic is an important one in the microwave field since most very broad band coaxial and stripline components are based on such coupled lines. The book is divided into nine main sections. The first three consist of papers dealing with the calculation of the coupling between lines of various geometrical shapes, plus an important short paper by Podell on a technique for realizing high directivity
497
Book Reviews in microstrip couplers. Section 4 is a bibliography, while section 5 republishes some of the earlier work in the field. Sections 6 and 7 deal with symmetric and asymmetric couplers of the multi-step type, and section 8 is concerned with tapered designs. The final section is intended to introduce the reader to the topic of slot line. This book contains almost all important papers published on the subject to the middle of 1970, and references those few papers which were excluded for reasons of space. Most of the papers have appeared in the IEEE Trans. on Microwave Theory and Techniques, but it is most useful to have them collected in one source particularly since several errors present in the original papers have been corrected (however several have not!), and at least two papers have been republished from obscure sources. The work will be especially valuable to new research workers entering the field since it will save much of the literature delving inherent in such new enterprises. It is recommended for all libraries end microwave people connected with the components field. Microwave
R. LEVY Development Laboratories, Inc. Needham, Massachusetts
DIGITALCOMPUTERPROCESSCONTROL, by Cecil L. Smith. 289 pages, 6x 9 in. Intext Educational Publishers, Scranton, Pa., 1972. Price $12.95 (approx. $4.90). The basic objective of this book is to present techniques by which digital computers can be used to generate a larger economic return from a process than can be obtained by using conventional control instrumentation. Unfortunately, the book falls short of this objective. The author presents instead a survey of hardware and software used in the process computer configuration, the design techniques us’mg z-tr&sforms,~identif%&ion, feedforwardfeedback control systems, adaptive control, and a rather cursory treatment of ontimal control. In fact. the chanter on optimal control has a negative effect on the reader since it makes dynamic programming appear too restrictive to be of I
498
any practical value and, in the use of Pontryagin’s maximum principle, it overestimates the difficulty of solving the twopoint boundary value problem for nonlinear systems. The chapter on identification barely serves as an introduction since it does not take into account the effects of correlated noise which cannot be neglected for many physical processes, and limits the discussion to processes with one input and one output. But the author brings the reader into the realm of physical systems by examining the control of a distillation column and a chemical reactor. He also considers the practical aspects of choosing the sampling time although the optimum sampling time is not the sampling time corresponding to the point where the cost of decrease in loop performance equals the cost of computing effort. The lack of precision in the deflnit,ion and in the use of fundamental terms (such as physical model vs mathematical model, factor vs term, algorithm, functional, and A) coupled with minor errors in various equations (e.g. Eqs. 3-17, 6-19, 620, 621, 7-22, 7-23, 9-26 and 9-27) and the occasional omission of a period over a symbol (to denote differentiation with respect to time) will probably make the book difficult to read for one not familiar with the field. But since the book is intended for graduate instruction, these are of minor consequence as compared to its overall shortcomings in not providing sufficient depth for evaluating the real possibilities of digital computer control. Department
REIN Luus of Chemical Engineering University of Toronto Toronto, Ontario, Canada
ATOMIC AND MOLECULAR RADIATION r(,___:_.-_-1 _~~_~~.672 PHYSICS, by I cr. fi bnrls~“pn”r”u oases. diaeran is, 6 x 9 in. Wiley 1 ionographs in Chemical Physics (eds. John B. Birks and Sean P. McGlynn). New York, John Wiley & Sons, 1971. Price, $29.00 (approx. fll.50). 1.
I
Intended for the postgraduate student and research worker in the field, Christophorou states that the book “deals with
Journalof
The
Franklin Institute
Reviews
LOGIC DESIGN OF DIGITAL SYSTEMS, by Donald L. Dietmeyer. 800 pages, diagrams, 6 x 9 in. Boston, Mass., Allyn & Bacon, 1971 and 1972. Due to the growing importance of automated design techniques in digital system design (1, 2), this book, with its emphasis on computer-implementable algorithmic approaches to logic design, is a useful addition to the field. The book covers a wide range of topics from the basic to the advanced. Chapter 1, which covers number systems and some of the binary codes, provides an adequate background for the other chapters. Then set theory, Boolean algebra, switching functions and their representation are introduced, along with Minimization using simple examples. Karnaugh maps and Quine-McCluskey algorithm is described and illustrated by practical design examples. Chapter 3 is concerned with algorithmic synthesis of combinational networks. Apart from developing the theory and algorithms, FORTRAN programs implementing many of the algorithms are also given. These programs can be used if the operators defined are implemented on a computer as FORTRAN subroutines. Next is an introduction to the analysis and synthesis of synchronous sequential networks. Hazards in combinational networks and analysis and synthesis of asynchronous sequential networks are covered in Chap. 5. A good overall introduction to digital system architecture and design is given. A simple digital computer is described and used a.s a vehicle to illustrate the theory, thus making the concepts easier to understand. A section on microprogramming is included. In going through the book in detail, this reviewer noted that very little background is needed to study the book as it is selfcontained. It is clearly written, easy to follow, and contains many practical examples. A large number of student exercise problems (with answers to many of them) and a comprehensive list of references are included at the end of each
chapter. A digital-system design language (3), useful for describing large digital networks, is described and used throughout,. The book does not deal with redundancy techniques used for increasing reliability, except for information redundancy. Also, there is only a brief treatment on threshold devices. However, these omissions detract from the completeness of the book in only a minor way. Overall, this book is extremely wellsuited for use in the classroom. It is also excellent as a text for self-study and as a reference. RAMACHENDRA P. BATNI Department of Electrical Engineering University of Wisconsin Madison, Wisconsin References
(1) Computer,
Vol. 5, No. 3, May/June 1972. (2) M. A. Breuer (Ed.), “Design Automation of Digital Systems: Theory and Techniques. Volume I, Hardware”, Prentice-Hall, Englewood Cliffs, N.J., 1972. (3) J. R. Duley and D. L. Dietmeyer, “A Digital System Design Language (DDL)“, IEEE Trans. Computers, Vol. C-17, pp. 850-861, Sept. 1968.
PARALLEL COUPLED LINES AND DIRECTIONALCOUPLERS,edited by Leo Young. 274 pages, diagrams. Dedham, Mass., 1972. Price $11.95 Artech House, (approx. $4.25). This book consists of a collection of 30 papers on the subject of electromagnetic coupling between a pair of transmission lines propagating in TEMtype modes. The topic is an important one in the microwave field since most very broad band coaxial and stripline components are based on such coupled lines. The book is divided into nine main sections. The first three consist of papers dealing with the calculation of the coupling between lines of various geometrical shapes, plus an important short paper by Podell on a technique for realizing high directivity
497
Book Reviews in microstrip couplers. Section 4 is a bibliography, while section 5 republishes some of the earlier work in the field. Sections 6 and 7 deal with symmetric and asymmetric couplers of the multi-step type, and section 8 is concerned with tapered designs. The final section is intended to introduce the reader to the topic of slot line. This book contains almost all important papers published on the subject to the middle of 1970, and references those few papers which were excluded for reasons of space. Most of the papers have appeared in the IEEE Trans. on Microwave Theory and Techniques, but it is most useful to have them collected in one source particularly since several errors present in the original papers have been corrected (however several have not!), and at least two papers have been republished from obscure sources. The work will be especially valuable to new research workers entering the field since it will save much of the literature delving inherent in such new enterprises. It is recommended for all libraries end microwave people connected with the components field. Microwave
R. LEVY Development Laboratories, Inc. Needham, Massachusetts
DIGITALCOMPUTERPROCESSCONTROL, by Cecil L. Smith. 289 pages, 6x 9 in. Intext Educational Publishers, Scranton, Pa., 1972. Price $12.95 (approx. $4.90). The basic objective of this book is to present techniques by which digital computers can be used to generate a larger economic return from a process than can be obtained by using conventional control instrumentation. Unfortunately, the book falls short of this objective. The author presents instead a survey of hardware and software used in the process computer configuration, the design techniques us’mg z-tr&sforms,~identif%&ion, feedforwardfeedback control systems, adaptive control, and a rather cursory treatment of ontimal control. In fact. the chanter on optimal control has a negative effect on the reader since it makes dynamic programming appear too restrictive to be of I
498
any practical value and, in the use of Pontryagin’s maximum principle, it overestimates the difficulty of solving the twopoint boundary value problem for nonlinear systems. The chapter on identification barely serves as an introduction since it does not take into account the effects of correlated noise which cannot be neglected for many physical processes, and limits the discussion to processes with one input and one output. But the author brings the reader into the realm of physical systems by examining the control of a distillation column and a chemical reactor. He also considers the practical aspects of choosing the sampling time although the optimum sampling time is not the sampling time corresponding to the point where the cost of decrease in loop performance equals the cost of computing effort. The lack of precision in the deflnit,ion and in the use of fundamental terms (such as physical model vs mathematical model, factor vs term, algorithm, functional, and A) coupled with minor errors in various equations (e.g. Eqs. 3-17, 6-19, 620, 621, 7-22, 7-23, 9-26 and 9-27) and the occasional omission of a period over a symbol (to denote differentiation with respect to time) will probably make the book difficult to read for one not familiar with the field. But since the book is intended for graduate instruction, these are of minor consequence as compared to its overall shortcomings in not providing sufficient depth for evaluating the real possibilities of digital computer control. Department
REIN Luus of Chemical Engineering University of Toronto Toronto, Ontario, Canada
ATOMIC AND MOLECULAR RADIATION r(,___:_.-_-1 _~~_~~.672 PHYSICS, by I cr. fi bnrls~“pn”r”u oases. diaeran is, 6 x 9 in. Wiley 1 ionographs in Chemical Physics (eds. John B. Birks and Sean P. McGlynn). New York, John Wiley & Sons, 1971. Price, $29.00 (approx. fll.50). 1.
I
Intended for the postgraduate student and research worker in the field, Christophorou states that the book “deals with
Journalof
The
Franklin Institute