Abstract-Ultra-wideband (UWB) antennas have advantages such as high data rates, improved multipath resistance and low power consumption. In this work, UWB patch antennas based on electrically conductive adhesive were manufactured with a simple technique and evaluated in the laboratory. Results showed that the thickness of the samples ranged from 207 to 261 µm. The bandwidth optimization obtained was 200% compared to a traditional copper-layer antenna. UWB antennas showed an average bandwidth of 8.558 GHz in the region 609 MHz to 9.105 GHz. The antennas covered the whole of UHF band, L band, S band, C band and part of X band. Finally, the proposed technique allows reducing the size of patch by 70% for low frequencies of operation, while achieving a similar performance.

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In this work, a perfect absorber based on a split ring resonator structure is proposed and numerically analyzed. The software CST STUDIO was employed to carry out the numerical analysis and the optimization of the proposed structure. The electromagnetic properties of the proposed metamaterial cell were analyzed in the first phase of this study demonstrating that such structure resonates at 2.4 GHz and 4.2 GHz simultaneously. In fact, this structure has negative permittivity and permeability in these two bands. The optimization process has led us to obtain a compact resonator, which has a total size of 15 mm × 15 mm. Subsequently, the capacity of this structure as an absorber of electromagnetic energy is analyzed. The obtained results reveal that this structure has absorption efficiencies of 98.2% and 99.7% for the first and second bands respectively. Also, other characteristic parameters were evaluated. This shows that the proposed structure has a high electrical performance and can be used for the collection of electromagnetic energy, which can be used to power wireless sensor networks.

This work proposes and analyzes a low-cost fixed microstrip beamforming system based on a uniform linear array with four rectangular patch antennas controlled by a Butler matrix that operates in the 2.4 GHz ISM band. A 4×4 Butler matrix consisting of four hybrid quadrature directional couplers, two crossovers, and two 45° phase shifters was designed and implemented to control the beam direction of the entire system. Similarly, a comparative study is performed between two different antenna arrays, the first consisting of a conventional linear antenna array and the second antenna array consisting of four patch antennas loaded with metamaterial structures on the ground plane. Finally, the electrical performance of both smart beamforming systems was evaluated, and their potential application as a wireless power transmitter was evaluated. Four beams with distinct orientations were created in each situation. The smart antenna based on a conventional array has a higher gain, while the smart antenna based on metamaterial structures has a higher HPBW.

In this paper the measurement of chromatic dispersion in a novel Side-hole PCF is reported. We chose a simple technique based on a Michelson interferometer. The results open the possibility of tunable chromatic dispersion compensators.