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This paper presents a patch loaded slot antenna for super wideband (SWB) application. To obtain SWB characteristic, the proposed antenna geometry combined a rectangular slot and an overlying patch excited by a trident shaped microstrip feed. It is observed that the hybrid nature of the proposed antenna effectively enhances the impedance bandwidth up to 120%, by combining the resonance of both patch and slot. Besides, it is investigated that after converting the conventional tapered feed into the trident shape feed, the impedance bandwidth is increased further from 120 to 167% ranging between 1.25 and 15 GHz. Moreover, one U-shaped slot and two L-shaped stubs are inserted into the antenna design to introduce the dual-band rejection property from 1.8 to 2.4 GHz (GSM 1800, Wi-Fi 2.1 and 2.4) and 3.1–4.2 GHz (WiMAX and C-band). Further, to validate the simulation results a prototype is practically constructed and tested. The measured result demonstrates that the designed antenna offered an impedance bandwidth of 170.3% from 1.2 to 15 GHz. Both frequency and time domain analysis ensure the suitability of the designed antenna for SWB applications. [ABSTRACT FROM AUTHOR]

This paper presents effect of the weather impairments on a high altitude platform (HAP) broadband wireless communication system. It is shown that attenuation due to oxygen, water vapor, fog, cloud, and rain has significant effect on a radio link which is operating in a millimeter frequency range. Channel capacity is calculated for different seasons using Shannon’s channel capacity theorem. The location of HAP is taken to be Delhi (India). Further, it is considered that a user and the HAP platform are stationary. [ABSTRACT FROM AUTHOR]