This paper presents a novel dual-band planar inverted-e-shaped antenna (PIEA) using defected ground structure (DGS) for Bluetooth and wireless local area network (WLAN) applications. The PIEA can reduce electromagnetic interferences (EMIs) and it is constructed on a compact printed circuit board (PCB) size of 10 × 5 × 4？mm3. Experimental results indicate that the antenna with a compact meandered slit can improve the operating impedance matching and bandwidths at 2.4 and 5.5？GHz. The measured power gains at 2.4 and 5.5？GHz band are 1.99 and 3.71？dBi; antenna efficiencies are about 49.33% and 55.23%, respectively. Finally, the good performances of the proposed antenna can highly promote for mobile device applications. 1. Introduction In recent years, wireless local area networks (WLANs) have tremendously advanced. The WLAN facilitates the wireless connection between laptop computers, mobile devices, and other equipment within a local area. Small volume antennas are highly attractive for Bluetooth and wireless local area network (WLAN)/worldwide interoperability mobile access (WiMAX) applications [1–4]. Additionally, the frequency bands located around 2.4？GHz and 5？GHz have been widely used in Bluetooth and WLAN/WiMAX simultaneously. A multiband antenna is thus more efficient than multiple antennas specifically designed to operate on each frequency band. Dual-band antennas, composed of a pair of dipoles or of a T-shaped monopole, have been presented to cover the frequency band of 2.4 and 5？GHz in [5, 6]. According to [7–15], the meander slit antenna includes many basic folded elements in various patterns and it can produce various resonant frequencies markedly lower than resonances frequency of a single-element antenna under the same length. Apparently, owing to the various current cancellation and reinforcements, a larger number of higher resonances frequencies can occur on a meander monopole antenna than on a simple monopole of the same length [7–11]. The antenna with a meandered slit can reduce the tag sizes. Moreover, meandered slit can use open-end slots in the ground plane, generally located under the radiating patch. The size reduction method is highly promising for implementing practical antenna. Previous work [12–15] described the feasibility of using a slotted ground plane for broadening the operational bandwidth of a small terminal antenna. Additionally, due to their small size, the planar inverted-F antennas (PIFAs) or monopole antennas have a narrow bandwidth, especially at 5？GHz band. Numerous dual-band designs have been developed for WLAN
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