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Design of an ultra‐wideband MIMO antenna for PDA applications

A low‐profile, ultra‐wideband (UWB), multi‐input multi‐output (MIMO) antenna for a personal digital assistant application is proposed.To improve the impedance bandwidth, a 2 mm × 1 mm connecting strip is used on each antenna element. The isolation characteristic between the two antenna elements is improved by inserting two T‐shaped stubs. The optimized design parameters were obtained through parametric analysis. The designed antenna has a 10‐dB return loss bandwidth of 9 GHz (2.2–11.2 GHz) covering the WiBro, Bluetooth, WiMax, S‐DMB, and UWB frequency bands, with an isolation characteristic below −20 dB over the operating frequency. Additionally, the envelope correlation coefficient is less than 0.12. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2165–2170, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25478