AbstractThis article describes a novel compact wideband slot antenna comprising of an E‐shaped patch that is excited with a trident‐shaped microstrip feed‐line structure. The antenna design exhibits a very wide operating bandwidth of over 163% with S11 < −10 dB in the frequency range 2–19.95 GHz. The antenna's radiation characteristics are stable across the 2–12 GHz band. The proposed antenna exhibits high polarization purity with cross‐polarization level that is well below −50 dB. A comprehensive parametric study was performed on the antenna to fully understand the effects of various antenna parameters that enable optimization of the antenna's performance. This antenna easily fulfills the requirements for ultra‐wideband wireless communication systems as specified by federal communication commission over the designated band 3.1–10.6 GHz. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1001–1006, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25096