volume | PIER Journals

Abstract

This paper investigates a miniaturized resonant antenna that comprises a meandered monopole and a partial ground plane. A bandwidth enhancement is found using the ground plane on the back side of the circuit board where the entire communication system resides. The meandered monopole together with the ground plane forms a wideband dipole antenna. The design shows over 25% 10 dB impedance bandwidth at 2.5 GHz ISM band with a monopole area of 300 mils by 166 mils on a small circuit board and a backside ground plane 1500 mils by 600 mils. The wire length is about one third and the Q factor is about twice as compared against the case of using a straight quarter-wave microstrip monopole. The antenna Q factor as a function ground plane area is characterized. The use of circuit ground as a part of an antenna should find useful applications in portable wireless systems. Good agreements are found between simulated and measured antenna gain patterns and return loss.

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Dr. Hung Yu Yang

Dr. Yanyan Zhang