Small square slot antenna with dual band-notch function by using inverted T-shaped ring conductor-backed plane

In this article, a novel method for designing a new slot antenna with dual band-notch characteristic for ultra-wideband applications has been presented. By inserting a coupled inverted T-shaped ring strip on the other side of the substrate, a dual band-notch function generated, also additional resonance is excited and hence much wider impedance bandwidth can be produced, especially at the higher band. The measured results reveal that the presented dual band-notch slot antenna offers a wide bandwidth with two notched bands, covering all the 5.2/5.8-GHz wireless local area network, 3.5/5.5-GHz WiMAX, and 4-GHz C bands. The designed antenna has a small size of 20 × 20 mm2. Good return loss and radiation pattern characteristics are obtained in the frequency band of interest. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2267–2270, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27057