US Patent 8228251 Ultra-wideband, low profile antenna

An ultra-wideband, low profile antenna is provided. The antenna includes a ground plane substrate and a radiating element. The radiating element includes at least two loop sections, wherein each of the at least two loop sections is electrically connected to a feed network and to the ground plane substrate. The radiating element is configured to radiate over a first frequency band when the feed network provides an in-phase input signal to the at least two loop sections and to radiate over a second frequency band when the feed network provides an out-of-phase input signal to the at least two loop sections. The second frequency band includes a lower frequency than the first frequency band.