The Book End

ELEKTA Professional

Stephan Weber
Noble Publishing Corp.
User Manual and CD-ROM; $99

This interactive software package is a knowledge-based system for analog electronics designed for everyday engineering assistance. It includes an encyclopedia of electronic principles, tutorial instruction with interactive examples and an extensive set of design and analysis utilities.

The software is Windows® based and organized as familiar help files. The program comprises tutorial background information on hundreds of electronic topics with ample explanations and examples, dozens of utility program screens to perform design-related calculations, engineering support to aid in starting a project and to assist during advanced circuit design and simulation activities, and tools to set up the circuit and simulate it in SPICE.

The encyclopedia features an overview, menu, tools, bibliography, World Wide Web references, important addresses, history and abbreviations, and symbols. A search function is available and green text links take the user to related topics. In addition, back and history functions are available.

There are a large number of tools incorporated that are designed for solving specific electronic tasks that can be accessed directly from Windows independent of the ELEKTA program. These tools include math aids, fundamentals of electrical engineering, filter circuits and RF design, transistor and amplifier circuits, and SPICE parameter extraction.

The circuit simulation capability starts with a schematic (the program contains more than 180 complete schematics that can be varied by the user). Once the time or frequency range is chosen, the circuit simulation can be accomplished. The software includes a compact version of Microsim’s PSpice Design Center program and uses APLAC, a program developed in cooperation with the University of Helsinki and Nokia, for more specific simulations. SSPICE is also included, which enables the user to perform analytical calculations of linear circuits, thus yielding an equation for the transfer function. The interactive mathematics section provides math fundamentals in the form of equations and graphs that, in many cases, can be modified interactively.

To order this software, contact:

Noble Publishing Corp.,
4772 Stone Dr.,
Tucker, GA
(770) 908-2320.

Behavioral Modeling of Nonlinear RF and Microwave Devices

Thomas R. Turlington
Artech House Inc.
368 pages; $89, £61
ISBN: 1-58053-014-1

The methodology of behavior modeling — developing equations that acceptably reproduce an observed object’s linear or nonlinear behavior — is the subject of this book. The objects of interest in this text are electronic in nature and operate at RF and microwave frequencies. The curve-fitting methods described can generate equations that provide acceptably accurate fits to data that otherwise cannot be represented by a single equation. Coefficients used in these new curve-fit equations are measurable parameters such as power, voltage, current, gain, phase, noise figure and compression coefficient.

The new curve-fit methods are applied to microwave and RF transistor devices. Nonlinear models are developed for bipolar and MESFET devices used in amplifiers. The models then are used to generate characteristic amplifier data as a function of bias current and drive level. The data generated by the behavior models of transistors at different bias conditions and varying input power levels at saturation and cutoff are the basis for developing nonlinear behavior models for class A and AB amplifiers.

New modeling techniques are used to characterize these amplifiers and develop relationships among the 1 dB compression point, third-order intercept, power output at saturation, small-signal gain and other characteristics. The unique amplifier stage behavior model equations then are applied to cascading amplifiers and trade-off areas are developed that illustrate the relationship between noise figure, current consumption and input third-order intercept as functions of amplifier stage gain distribution and compression characteristic. Nonlinear behavioral model equations of cascaded stages are combined to develop a direct relationship between saturated power output of each cascaded stage, compression characteristic, small-signal gain per stage and maximum saturated power output available. Probability distributions of small-signal gain, saturated power output, bias current and noise figure also are discussed.

To order this book, contact:

Artech House Inc.,
685 Canton St.,
Norwood, MA 02062
(781) 769-9750, ext. 4002; or

46 Gillingham St.,
London SW1V 1HH, UK
+44 (0) 171 973 8077.