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This paper proposes design and investigates of graphene based plasmonic microstrip antenna for terahertz high speed communication and application systems 0.1-20 THz. The proposed antenna structure composed of graphenebased rectangular patch and transmission line mounted on a grounded silicone dioxide substrate. SPP (Surface Plasmon Polariton) waves that appear in graphene at THz band is analyzed. The proposed antenna simulation was done by using numerical method CST program. The simulation results show the scattering parameter S11 less than -10 dB at frequency band (0.1-20) THz. Also, the presented antenna system has a good gain along the frequency band.

The demand for electricity is increasing day by day and we have to produce more electrical energy to meet the load demands. Most of the experts prefer to extend the existing electrical networks over building the new network with greater costs. In this paper, the implementation of the flexible AC transmission systems (FACTS) devices in a simple electrical network is described. FACTS devices enhance power transfer capacity of the line without laying out new transmission line. These devices also protect the system from overloading in case of any contingency in the electrical network. Moreover, this paper describes the impacts of FACTS devices on improving the voltage stability and power handling capability of a transmission line. The proposed methods for the controllable flow of active and reactive power in a transmission line are also elaborated. A simple electrical system is examined to explain the improvement in the constraints of power system using FACTS devices.

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In this paper, a compact configuration of zeroth-order resonator antenna is described. The unit cell zeroth-order resonator properties are introduced by composite right/left-handed transmission line approach is fed by coplanar waveguide. The proposed resonator is analyzed by changing the coupling space and stub length of the unit cell. The size of implemented resonator is (0.185 λ0 × 0.185 λ0 × 0.027 λ0) at the centre frequency. In this work, a zeroth-order resonator antenna design with enhanced bandwidth has been presented, and the size reduction by using the metamaterial inclusion. The proposed zeroth-order resonant antenna (ZORA) achieves a 64% reduction compared to a traditional λ/2 microstrip patch antenna. The bandwidth for the 10 dB return loss is 5.66 GHz (2.76 GHz to 8.42 GHz), the peak value of gain is 0.8 dBi and radiation efficiency of the designed antenna is 87% at 5.5 GHz. The return loss is about -59.48 dB at the center frequency. The competition among the simulated performances and other antennas shows that the proposed resonator achieves wide bandwidth. The performance of zeroth-order resonator antenna is evaluated by full-wave electromagnetic (EM) simulator HFSS11.