• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.3 s.118
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• pp.323-333
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• 2007

In this paper, a new MDAS-DR antenna structure designed to efficiently shape a flat-topped radiation pattern is proposed. The antenna structure is composed of a stacked micro-strip patch exciter and a multi-layered disk array structure(MDAS) surrounded by a dielectric ring. The MDAS, which was supplied by a stacked microstrip patch exciter with radiating power, can form a flat-topped radiation pattern in a far field by a mutual interaction with the surrounding dielectric ring. Therefore, the design parameters of the dielectric ring and the MDAS structure are important design parameters for shaping a flat-topped radiation pattern. The proposed antenna used twelve multi-layered disk array elements and a Teflon material with a dielectric constant of 2.05. An antenna operated at 10 GHz$(9.6\sim10.4\;GHz)$ was designed in order to verify the effectiveness of the proposed antenna structure. The commercial simulator of CST Microwave $Studio^{TM}$, which was adapted to a 3-D antenna structure analysis, was used for the simulation. The antenna breadboard was also fabricated and its electrical performance was measured in an anechoic antenna chamber. The measured results of the antenna breadboard with a flat-topped radiation pattern were found to be in good agreement with the simulated one. The MDAS-DR antenna gain measured at 10 GHz was 11.18 dBi, and the MDAS-DR antenna was capable of shaping a good flat-topped radiation pattern with a beam-width of about $40^{\circ}$, at least within a fractional bandwidth of 8.0 %.