This paper presents a printed slot antenna using the printed structure in order to improve its dual-band and compact size performances. The printed slot structure is used as additional resonators to produce dual-band operation for covering the worldwide interoperability for microwave access (WiMAX) and the 5.2-GHz wireless local area network (WLAN) bands. In order to achieve wideband and multi-band operation, the slot antennas with a slotted structure and an inverted-L slot structure for covering the wireless communication operations are developed. Finally, we propose a novel and compact printed slot antenna with mixing slot structures to obtain and cover for the 2.4-GHz WLAN (2.4--2.484 GHz), the WiMAX (IEEE 802.16e in the Taiwan: 2.5--2.69/3.5--3.65 GHz), and the 5-GHz WLAN (5.15--5.35/5.725--5.825 GHz). Several properties of the proposed antennas for dual- and multi-band characterize radiation performances such as impedance bandwidth and radiation pattern. Measured gain has been confirmed experimentally for the multi-band wireless communication systems.
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