Abstract

Gain is an important parameter of the antenna through which the performance of the antenna is determined. Generally to increase the gain of the antenna, array configuration will be used but the overall size of the antenna will be increased. A method to enhance gain of a fractal antenna is investigated by partially removing the substrate surrounding the patch. The partial substrate removal reduces the losses due to surface waves. The effects of substrate removal in different configurations on the gain of the antenna are studied numerically and simulated. Compared to a conventional patch antenna, the antennas with partial substrate removal can enhance gain, for example, up to 2.7 dB. Furthermore, it is observed that the enhancement of gain is more due to the loss reduction of surface waves and dielectric substrate than increased patch size when the effective dielectric constant of substrate is lowered. Such a technique can be applied on designs, operating at higher frequencies where by surface wave and substrate losses are more significant.

Keywords:

Fractal antenna, gain enhancement, radiation characteristics, substrate removal,

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Competing interests

The authors have no competing interests.

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