With the concept of everywhere and every time wireless communications, there are lot of developments in various wireless operations including the mobile phones, PDA, Bluetooth, wireless local area network (WLAN), and worldwide interoperability for microwave access (WiMAX). The WLAN system usually designed as the backbones of short range wireless communication systems supporting the IEEE802.11b/g/a (2.4–2.484 GHz, 5.15–5.35 GHz, and 5.725–5.825 GHz) standards, is now developed to be used on mobile phones and other handheld devices. Recently, the WiMAX has emerged for mobile broadband wireless internet supporting the IEEE802.16e (2.5–2.69 GHz, 3.3–3.7 GHz, and 5.25–5.85 GHz) standard. Clearly, both the WLAN and the WiMAX have operating frequencies close together. Therefore, these frequencies can be arranged into three bands including 2.4–2.7 GHz, 3.3–3.7 GHz, and 5.15–5.85 GHz, respectively. Obviously, the antenna is an importance device for wireless systems which cannot much change, because the antenna could maintain good characteristics whereas employed in various applications. A printed planar antenna is usually designed for covering those WLAN/WiMAX bands. Furthermore, the printed planar antennas are designed with many techniques. For examples, the dual band printed planar antenna with a pair slit loading for triple bands generating is designed by [1] and the dual rectangular ring patch is employed for triple band generating [2]. Moreover, the printed antennas for WLAN/WiMAX are presented by [3] and [4]. The former antenna responds dual wideband and the latter antenna capably responds to triple band. Consequently, a multiband monopole antenna with dual band response is proposed [5]; however, this antenna cannot support the frequency band of 3.5 GHz. The coupling-fed multiband, 2.5/3.5/5.5 GHz, is presented by [6]; however, the middle band has too narrow bandwidth. The triple band printed mono- ole antennas are presented by [7]–[9], these antennas capably provide frequency bands covering all WLAN/WiMAX systems; however, these antennas are designed with double metallic side on substrate leading to more complicate structures.
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