This book presents the current state of the art of ultra wideband (UWB) antennas, from theory specific for these radiators to guidelines for the design of omnidirectional and directional UWB antennas. Featuring illustrative examples, design equations, CST MICROWAVE STUDIO® simulations, and MATLAB® plot generations, the text delivers a brief exposition of numerical methods for electromagnetics oriented to antennas, describes solid-planar equivalence, addresses the time domain signal analysis for UWB antennas, and compares the performance of different UWB antennas, supplying insight into particular tendencies and unresolved problems.