A simple U‐shaped printed ultra‐wideband antenna with WLAN band rejection

In this article, a novel printed ultra‐wideband (UWB) antenna with band stop characteristics is proposed. The proposed antenna is a simple U‐shaped monopole structure where a rectangular strip is placed on both sides at the top of semi annular ring monopole structure. The band rejection characteristic is achieved by introducing a pair of L‐shaped slots in the ground plane to prevent interference due to wireless local area network (WLAN) systems operating within ultra‐wideband. To achieve the desired UWB response with WLAN band notched characteristics, the dimensions of rectangular strip, L‐shaped slot, symmetrical step slot on the both edge of ground plane, a single slot in the center of the ground plane and the gap between the ground plane and the radiating structure are optimized. Frequency rejection characteristics depend on the dimension of L‐shaped slot and can be fine controlled using other parameters. The antenna structure is designed, fabricated and tested. The simulation and measurement results show that the return loss = −10 dB from 3.09 to 10.6 GHz with band stop characteristics in 5.11–6.14 GHz frequency band. The radiation characteristics show its suitability for indoor wireless communication. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26091