A sensitive photoinduced current transient spectroscopy technique using a computer for data acquisition and processing has been worked out. It enables one to determine separately the signatures and concentrations of deep levels in high-resistivity bulk materials. In a previous paper, possible signal processing has been analyzed from a rather theoretical point of view. In the present report, the instrumentation used as well as the experimental procedure and some practical and complementary aspects will be discussed. For the determination of reliable trap signatures, we have proposed and tested a four-gate data treatment that eliminates, or at least reduces, many of the problems encountered when using the usual double-gate procedure provided some experimental precautions are taken. Yet the double-gate method is useful when one wants to estimate the trap concentrations. A standard experimental procedure is presented that takes into account the temperature dependence of the mobility/free-lifetime product of thermal emitted carriers, and its possible variation during the relaxation of the traps.

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Abstract-Recently, the RF/microwave electronic technology evolved with the consideration of plastic and organic substrates. Such a technology offers two-folded benefits: in one side for lowering the fabrication cost and in another side for the possibility to bend electronic devices. Such a technology is particularly interesting for the implementation of antenna system. This paper is dealing with the design of flexible microstrip 1×2 antenna array. Theoretical approach on the typically symmetrical 1×2 antenna array is proposed. The design methodology of microstrip antenna combined with 1 : 2 T-power divider (T-PWD) is described. Based on the transmission line theory, the S-parameter model of the antenna system with non-standard reference load is established. Then, the microstrip antenna passive system is theoretical analysed in function of the physical dimensions of the designed structure. The feasibility of the flexible antenna passive system is investigated with the proof-of-concept (POC) designed on Kapton substrate. The POC prototype consisted of microstrip 1 × 2 antenna array is designed to operate at about 5.8 GHz. Comparisons between the full wave simulated and measured return losses were performed. Then, simulated radiation pattern highlights the efficiency of the fabricated prototype of passive antenna array.

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