A Compact Printed Slot Antenna with High Out-of-band Rejection for WLAN/WiMAX Applications

The suppression of electromagnetic interferences (EMIs) caused by the out-of-band operation is required for broadband antennas. To achieve this purpose, a compact broadband printed slot antenna with build-in filters for band notching is presented. The filters, including I-shaped and inverse L-shaped narrow slits and an L-shaped conductor strip, whose lengths correspond to half wavelengths, were integrated in the proposed antenna structure. The mitigation of the EMIs at the frequency ranges of 2.7 to 3.2 GHz, 4.1 to 4.7 GHz, and over 6.1 GHz was obtained. The proposed antenna capably operated at WLAN/WiMAX frequency ranges of 2.26 to 2.68 GHz, 3.28 to 4.09 GHz, and 4.75 to 6.04 GHz. The nearly omni-directional and likely bi-directional radiation patterns were given by the proposed antenna in xz and yz planes, respectively. Therefore, this antenna is suitable for various WLAN/WiMAX applications.