Microwave Journal 

About: Microwave Journal is an academic journal. The journal publishes majorly in the area(s): Amplifier & Microstrip. It has an ISSN identifier of 0192-6225. Over the lifetime, 863 publications have been published receiving 10485 citations.

Electromagnetic Optimization by Genetic Algorithms

Abstract: From the Publisher: Authoritative coverage of a revolutionary technique for overcoming problems in electromagnetic design Genetic algorithms are stochastic search procedures modeled on the Darwinian concepts of natural selection and evolution. The machinery of genetic algorithms utilizes an optimization methodology that allows a global search of the cost surface via statistical random processes dictated by the Darwinian evolutionary concept. These easily programmed and readily implemented procedures robustly locate extrema of highly multimodal functions and therefore are particularly well suited to finding solutions to a broad range of electromagnetic optimization problems. Electromagnetic Optimization by Genetic Algorithms is the first book devoted exclusively to the application of genetic algorithms to electromagnetic device design. Compiled by two highly competent and well-respected members of the electromagnetics community, this book describes numerous applications of genetic algorithms to the design and optimization of various low- and high-frequency electromagnetic components. Special features include: *Introduction by David E. Goldberg, "A Meditation on the Application of Genetic Algorithms" *Design of linear and planar arrays using genetic algorithms *Application of genetic algorithms to the design of broadband, wire, and integrated antennas *Genetic algorithm—driven design of dielectric gratings and frequency-selective surfaces *Synthesis of magnetostatic devices using genetic algorithms *Application of genetic algorithms to multiobjective electromagnetic backscattering optimization *A comprehensive list of the up-to-date references applicable to electromagneticdesign problemsSupplemented with more than 250 illustrations, Electromagnetic Optimization by Genetic Algorithms is a powerful resource for electrical engineers interested in modern electromagnetic designs and an indispensable reference for university researchers.

Optimum design for linearity and efficiency of a microwave doherty amplifier using a new load matching technique

Abstract: A Doherty amplifier with full load matching circuits of the carrier and peaking amplifiers at both low and high power levels is demonstrated for the first time. In the circuit design, sections of transmission lines are inserted in the load matching network for power-level-dependent load impedances. The circuit elements and bias points are designed and optimized using a large-signal harmonic balance simulation to offer simultaneous improvements in linearity and efficiency. Two 1.4 GHz Doherty amplifiers have been implemented using silicon LDMOS FETs. The RF performances of the Doherty amplifier-I (a combination of a class B carrier amplifier and a bias-tuned class C peaking amplifier) have been compared with those of a class B amplifier alone. The Doherty amplifier-II (a combination of a class AB carrier amplifier and a bias-tuned class C peaking amplifier) has been compared with a class AB amplifier alone. The new Doherty amplifiers show an improved linearity as well as higher efficiency.

A new model for broadband waveguide to microstrip transition design

Abstract: A new model is presented which permits the prediction of the resonant frequencies created by antipodal finline waveguide to microstrip transitions. The transition is modeled as a tapered transmission line in series with an infinite set of coupled resonant circuits. The resonant circuits are modeled as simple microwave resonant cavities of which the resonant frequencies are easily determined. The model is developed and the resonant frequencies determined for several different transitions. Experimental results are given to confirm the models.