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International audience; Conducting polymers have found significant applications in the past decade in industrial, scientific, and medical (ISM) fields. The characteristic features of conducting polymers like reversible proton doping, variable conductivity, facile synthesis, and low cost make them potential candidates in various microelectronic applications. Conventional microwave absorbing materials such as carbon and graphite in the powder form were blended with polyaniline as base at different proportions and microwave properties such as transmission, reflection, and shielding efficiency (SE) were evaluated from S parameter measurements using HP 8714ET network analyzer. The newly, developed polyaniline blend exhibits high-electromagnetic interference shielding efficiency when compared with previously developed materials and is a promising candidate for shielding applications. (C) 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 393-397, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOT 10.1002/mop.24939

This Letter points out the drop in radiation efficiency observed in active microstrip antennas with switching capabilities for inadequate values of the bias current. For a frequency agile antenna based on p-i-n diodes, a trade-off between the dc consumption of the diodes and the antenna gain is demonstrated. It is also shown that this type of integrated active antenna can be reasonably predicted by a simple resistor model of the diode in a TLM analysis. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 44–47, 2002; DOI 10.1002/mop.10226

This paper investigates the dual-frequency operation of a stacked microstrip antenna based on a small parasitic patch inserted slightly above an EBG patch. It is shown that the periodic texture of the EBG patch exhibits different behaviours for each frequency. It is also demonstrated that the high-impedance concept is no longer valid when a parasitic patch is located too close to the EBG material. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 207–209, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20589