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This paper discusses the resonance of a modified bifin fractal antenna in comparison to the corresponding printed modified bifin having a centrefeed microstrip line. The antennas are designed based on a finite biconical antenna operating at 1.575 GHz.The Global Positioning Satellite system receiver operates at this frequency. Modifications have been made to the bifin struclure which is half-wavelength long. The modification done on the bifin is intended to maintain the operating frequency. Hence, a compact structure can be obtained. By employing a configuration that resembles the fractal, the modified antenna is further reduced in size. The modified bifin antennas have 60' arm flare angle. The antennas have been successfully investigated using numerical simulations. The one-port performance of each modified fractal bifin is investigated and analysed. The structures operate at the corresponding frequency of operations.

The alternating current (AC) total interference of power lines may pose a threat to personnel and equipment in its vicinity. The main objective of this work is to determine the electromagnetic distribution and induced voltages on human body, equipment, and houses due to the AC total interference for different soil resistivities. The electromagnetic field and induced voltages may cause health problems to the human body and put it at risk. Two main approaches were used to compute the electromagnetic and induced voltages, namely the field approach, which is based on electromagnetic field distribution, and the circuit approach, which uses the circuit grounding analysis to compute the conductive interference and then uses the circuit based models to compute the inductive interference. Human body, steel houses and 10-km-long transmission line were modelled. The soil resistivity was varied, and the induced voltages obtained from both approaches were compared. Soil resistivity and soil structure are important parameters that affect the AC interference level. The results show that the touch voltage increases when the distance between electromagnetic source and human body increases. For high soil resistivity, the danger of the touch voltage becomes more prominent compared to that for low soil resistivity. Power system voltage level and soil resistivity are two key factors influencing the induced voltage level.

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