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A solution strategy is presented using a five-section transmission line impedance transformer aiming for multiple band matching network circuits. In this paper, the analysis, which is based on the transmission line theory and application of the evolutionary algorithm for the solution of the stated problem are explained. Design of the matching networks was performed and optimized at three different frequencies 1.8 GHz, 2.4 GHz and 3 GHz at the same time. Tests were performed for two different load configurations. The optimized design values obtained from the particle swarm optimization algorithm were verified for correctness using microwave simulator. After the fabrication of the circuits, the measurements were taken for these circuits for the validation of the design. From the observations that were made, it can be concluded that particle swarm optimization can be a good choice for the design and optimization of multiple band matching network circuits.

In this paper, an approach for teaching basic antenna theory and propagation to senior level undergraduate students for electrical engineering related fields is proposed and described. The method combines mathematical and theoretical studies with antenna design and laboratory measurements to reinforce the subject’s theoretical and practical aspects together. Topics discussed in lectures include performing antenna radiation calculations, learning how to make antenna radiation pattern measurements, and designing of antennas such as microstrip patch antenna. The education is based on teaching these principles and enabling students to make some antenna measurements. At the end of the semester, an analysis on learning outcomes of the course was performed and feedback from students was taken. The feedback from students showed that there was a huge satisfaction in terms of achieving the goals in learning outcomes. The course structure proposed can be a good example for instructors who teach antennas and propagation courses.

This letter presents the concept of particle swarm optimization (PSO) technique applied to two sets of microwave circuits: microstrip coupler and single shunt stub matching circuit. The PSO technique that is applied to these two set of designs is tested and compared with simulation results. The results show that PSO is an efficient method for solving these kinds of problems and can be applied for the design of microwave circuits. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1333–1336, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23369

Artificial immune systems are classified as computational systems inspired by theoretical immunology and are mechanisms that can solve complex problems. Clonal selection algorithm is a selection algorithm, which is derived as a special selection algorithm to this artificial intelligence concept. In this work, Clonal selection algorithm is applied to design a simple microwave matching network for a load with arbirtary impedance. The results obtained were tested in a microwave simulator and indicated that clonal selection algorithm can be very effectively applied for microwave design problems. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:991–993, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25935

This letter presents a proof-of-concept implementation of a millimeter-wave reflectometer for measuring complex reflection coefficients. The reflectometer is based on the six-port architecture and consists of a single section of WR-10 rectangular waveguide and a set of three Schottky power detectors. Design considerations as well as measurements in the 75 to 110 GHz range are described and discussed. Because of its simple architecture, the reflectometer is amenable to scaling for measurements well into the submillimeter-wave region of the spectrum.

A quasi-optical balanced doubler based on the dual-polarized sinuous antenna is presented. The input fundamental and output second harmonic signals are isolated by polarization and external wire-grid polarizers are used for impedance tuning. The doubler exhibits 1.6 dB of conversion gain at an input frequency of 5 GHz with a bandwidth of 10%.