Ultra-wideband omnidirectional conformable low-profile mode-0 spiral-mode microstrip (SMM) antenna

An ultra-wideband low-profile platform-conformable omnidirectional antenna based on the mode-0 SMM antenna has been developed. Its 10:1 gain bandwidth is slightly larger than that of the well-established conical monopole, yet its height is less than half that of the monopole. Compared with other well-known low-profile omnidirectional antennas with a gain bandwidth over 2:1, its gain bandwidth of 10:1 is much larger. Further size reduction improvement and performance enhancement for this new antenna are highly feasible.