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This paper develops a location based analog beamforming (BF) technique using compressive sensing (CS) to be feasible for millimeter wave (mmWave) wireless communication systems. The proposed scheme is based on exploiting the benefits of CS and localization to reduce mmWave beamforming (BF) complexity and enhance its performance compared with conventional mmWave analog BF techniques. CS theory is used to exploit the sparse nature of the mmWave propagation channel to estimate both the angle of departures (AoDs) and the angle of arrivals (AoAs) of the mmWave channel, and knowing the node location effectively reduces the number of BF vectors required for constructing the sensing matrix. Hence, a high accurate mmWave BF with a low set-up time can be obtained. Simulation analysis confirms the high effectiveness of the proposed mmWave BF technique compared to the conventional exhaustive search BF and the CS based BF without localization using random measurements.I.

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In this work, a solution cast technique was used to prepare flexible nanocomposite films of PVA/ PANI/Ag with different concentrations of PANI and AgNPs. The samples were described by X-ray diffraction (XRD), transmission electron microscope (TEM), and infrared spectroscopy, which confirmed the successful synthesis of the nanocomposite films. After that, the PVA/10%PANI/ 6%Ag nanocomposite film was irradiated by different influences of the oxygen ion beam (8 × 1017, 16 × 1017, and 24 × 1017 ions/cm2). The Ac conductivity, dielectric properties, electric modulus, complex impedance behaviour, and the energy density efficiency of the nonirradiated and irradiated films were measured in the frequency range of 100-106 Hz. The results revealed significant changes in these parameters with an increase in concentrations of PANI and Ag nanoparticles inside the host and also with ion beam irradiation. The reported improvements in this study would open the road for appropriating the unirradiated and irradiated nanocomposite films for electromagnetic shielding and optoelectronic applications.

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