WO/1996/027219 is referenced by 6 patents.
A planar meandering inverted-F antenna is provided, which is in one embodiment a broadband omnidirectional radiator and in another embodiment a narrow band omnidirectional radiator. The meandering inverted-F is a planar radiating structure having alternating cutouts along a longitudinal dimension of a planar radiating element or patch which is parallel to a nearly coextensive ground plane. In all cases the antenna structure as a whole has the advantage of an efficient omnidirectional radiation pattern from a structure which has a maximum dimension of less than 1/5 of the wavelength of the operating frequency and preferably as small as 1/10 of the wavelength of the operating frequency. Factors which impact frequency and bandwidth include: meandering patch length, vertical element (also called 'post') height and width, and permittivity of the dielectric spacer between the meandering patch and the ground plane. The structure is easily manufactured due to its simple design and absence of requirements of exotic materials or multidimensional shaping processes. Three embodiments are discussed: an air-dielectric version for broadband and low cost applications, a thick solid-dielectric version having broadband applications, and a thin solid-dielectric version having narrow band applications.