US Patent 7365692 Wideband omnidirectional antenna for plug and play device

A wideband omnidirectional antenna for a plug and play device includes a system ground plane, a radiating element, a feeding element. The radiating element is installed above an edge of the system ground plane and comprises a first sub-radiating element and a second sub-radiating element. The first sub-radiating element is parallel to the system ground plane. The second sub-radiating element is electronically connected to an edge of the first sub-radiating element in a foldable manner. The second sub-radiating element is approximately perpendicular to the first sub-radiating element and extends in an upright direction above the system ground plane when in use condition, and is approximately parallel to the first sub-radiating element and extends horizontally above the system ground plane when not in use condition. The feeding element is electronically connected to a signal source and is used for transmitting signals outputted from the signal source to the radiating element.