Patent ID: 7755559

Claim:
A dual-band omnidirectional antenna which comprises: a vertically stacked antenna array comprising, in order in the stack, a first dual-band dipole which resonates at a first frequency band and a second frequency band, a first single-band dipole which resonates only at the first frequency band, a second single-band dipole which resonates only at the first frequency band, and a second dual-band dipole, which resonates at the first frequency band and the second frequency band; the first frequency band being of a higher frequency that the second frequency band; a feed point for a transmission line located between the first single-band dipole and the second single-band dipole; and said single-band dipoles having DC shorts; the first single-band dipole and the second single-band dipole are non-symmetrical from the feed point whereby the phase contributions of the first dual-band dipole and the first single-band dipole are different from the phase contributions of the second single-band dipole and the second dual-band dipole.