In general, the electrically small antenna is defined as ka < 1. Where, k is a wave number and a is the maximum length of antenna. The efficiency, gain, impedance bandwidth and quality factor (Q) of small antenna are changed as maximum length of antenna. The narrow impedance bandwidth, high Q and low gain are generated by miniaturization of antenna. Besides, the impedance matching is very difficult due to high reactance of small antenna. The reduction of defects of small antenna is main consideration of electrically small antenna study.[1] Recently, EESA (Efficient Electrically Small Antenna), which was simulated by HFSS, was proposed by Richard W. Ziolkowski in 2006. The EESA was achieved using spherical shell of SNG (Single Negative) or DNG (Double Negative) materials. The efficiency, gain and FBW (Fractional Band Width) of EESA was improved by SNG or DNG materials. The SNG and DNG materials don't exist in nature. The SNG and DNG structures, which can be realized by meta-material structure, are necessary for design of meta-material structure based antenna.[2～4] In this paper, the proposed small antenna, which using negative permittivity meta-material structure is designed, achieves wide Q more than calculated Q{sub}L of chu limits. The equivalent circuit of proposed antenna is realized by Ansoft Designer. The proposed small antenna is optimized by 3-D field simulation tool, CST MWS (Micro Wave Studio)[5].
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