In this paper a modified version of the multi-band multiple ring monopole antenna is proposed. The height of the new design which consists of multiple half rings is half of the original one. The modified design is more attractive for low profile applications due to its lower height. The antenna is simulated and measured. It is shown that the simulation and measurement results are in good agreement. The performance of the modified version of the antenna is compared with the original design in terms of input characteristic and far field radiation patterns. It is shown that the multiband behaviour of the modified design is similar to the original one. However, there is a frequency shift between the operating bands of the new and the original antennas. The radiation patterns of the both antennas are similar to the conventional monopole antenna in lower operating frequency bands. However, degradation in radiation patterns of the both antennas is observed as frequency increases.
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