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A dual-band google lens logo-based patch antenna with defected ground structure was designed at 5.3 GHz for wireless applications and 7.4 GHz for wi-fi application. The designed antenna consists of a rounded rectangular patch antenna with a partial ground structure fed by a 50 Ω microstrip line. A google lens shaped logo is subtracted from the rounded rectangular patch and some regular polygon shaped slots are subtracted from the ground plane to obtain good dual-band characteristics and better results in terms of gain, VSWR, and return loss. The proposed antenna has a measurement of 20 × 20 × 1.6 mm3 and provides wide impedance bandwidths of 0.23 GHz (5.17‒5.40 GHz) and 0.16 GHz (7.33–7.49 GHz) at center frequencies of 5.3 GHz and 7.4 GHz, respectively. The antenna was designed and simulated using an ANSYS Electronics Desktop. Fabrication of the antenna was obtained using chemical etching and the results were measured by using an MS2037C Anritsu combinational analyzer. The return loss characteristics for dual bands are -20.56 dB at 5.3 GHz and -19.17 dB at 7.4 GHz, respectively, with a VSWR < 2 at both the frequencies and a 4 dB gain is obtained. [ABSTRACT FROM AUTHOR]

In this study, a three-pole hairpin structure was fabricated on the top of the substrate material and an open loop microstrip structure at the ground to give a modified triple-band BPF with a unique design. A Rogers (RT5880) material with εr = 2.2 and thickness of 1.27mm was used to fabricate the proposed structure. The space between two consecutive hairpin resonators has different distances d1 and d2 with values of 0.2mm and 0.4mm respectively. The proposed filter offers a compact size with low return loss. The equivalent LC circuit of the DGS and hairpin structure is obtained with the Ansys electronic desktop and by using simple circuit analysis. The desired microstrip triple-band BPF operates at the Ku band, resonates at 10.28GHz, 12GHz, and 14.62GHz, while the simulated and experimental results are almost identical. The proposed wideband BPF satisfies the International Telecommunication Union ((ITU) region 3 spectrum requirements. Direct Broadcast Service (DBS) and Fixed Satellite Service (FSS) in transmit mode respectively employ the frequency band 11.41-12.92GHz and 14-14.5GHz. [ABSTRACT FROM AUTHOR]

In this paper, an electrically small, planar antenna with broad side radiation pattern is presented. The design contains a dipole and a segmented circular loop which works equivalent to that of a magnetic dipole. A circular patch with slots is used to provide impedance matching. In general, electrically small antennas suffer from narrow bandwidth. In this paper, the reconfigurability of the small antenna for two different applications, 1.5GHz and 2.4GHz, is discussed. This reconfigurability was achieved by using a BAR 64-03W pin diode to adjust the resonant frequency. Two reconfigurable frequency bands were achieved at 1.5GHz and 2.4GHz with broad side radiation patterns. [ABSTRACT FROM AUTHOR]

Any wireless signal travelling in free space undergoes degradation due to the effects of the atmosphere that are naturally created in its pathway. Amongst all the degradation3 effects scintillation is significant at elevation angles above 5 degrees and also in tropical regions. Scintillation is mainly caused due to the rapid fluctuations in the refractive index of the layers of the atmosphere. Tropospheric scintillation is significant at frequencies above 3GHz. Ionosphere acts as a transparent layer above 10 GHz Tropospheric scintillation is receiving more attention because of the demand for higher bandwidth due to the congestion on the C and Ku bands. The rapid fluctuations induce variations in the received amplitude of the signal which decreases the quality of the signal. For systems with low elevation angle and the link operating with a frequency above 10GHz the effect of tropospheric scintillation is to be taken in to consideration. So, in this paper the effect of tropospheric scintillation is estimated for a Ku band beacon signal whose receiver is installed at K.L. University at a frequency of 11.7GHz. The scintillation amplitude is estimated using the beacon data and also using models that suit the tropical region. By comparing the scintillation amplitudes derived from the models and the with the one derived using beacon data, the best model that fits this geographical location is found which is the Otung model. [ABSTRACT FROM AUTHOR]