Novel designs of miniaturized patch antenna arrays with electromagnetic band gap (EBG) for wideband operation are presented in this paper. For this purpose, three unequal arms are fed by CPW-to-slotline with the T-shaped slotline transitions in order to widen the impedance bandwidth with three resonances. By adding two conventional mushroom-type EBG (CMT-EBG) structures on both sides of 100 Ω slotline transitions, a compact dual-band patch array is achieved. The proposed 1×2 patch array with CMT-EBG covers two bands with the measured ranges (S11≤-10 dB) of 6.65-6.95 GHz and 8.57- 11.53 GHz. Moreover, by applying an edge-shorted mushroomtype EBG (ESM-EBG) into the proposed array, a more size reduction is attained. Compared to the proposed array without EBG, the design with the ESM-EBG indicates more than 36% size reduction. Measurement results show that the proposed designs have good unidirectional radiation patterns and antenna gain (until 7 dBi) over the operating bands.
