Recent progress in impulse radiating antennas

We summarize here a number of advances in impulse radiating antennas. These devices are composed of a reflector and a broadband feed. We have demonstrated improved gain and reduced crosspolarisation by using feed arms located at /spl plusmn/30/spl deg/ to the vertical, as opposed to the original design that placed the arms at /spl plusmn/45/spl deg/. We have reduced the return loss (flattened the TDR) at the splitter, at the feed point (focus), and at the resistors in the feed arms. We have added a ground plane that enhances mechanical stability and reduces crosspolarisation. We have also improved the mechanical stability of the feed point.