Patent ID: 8248321

Claim:
A dual polarization multi-band antenna, comprising: a high band feed section having a forward end and a closed rearward end, the high band feed section comprising: a high band waveguide configured to support propagation of electromagnetic waves in a high wavelength band and to not support propagation of electromagnetic waves in a low wavelength band, and a high band vertical feed and a high band horizontal feed for coupling forward-propagating orthogonally-polarized high band electromagnetic waves into the high band waveguide; a low band feed section having a forward end and a rearward end, the low band feed section comprising: a dual band waveguide configured to support propagation of electromagnetic waves in the low wavelength band and the high wavelength band, and a low band vertical feed and a low band horizontal feed for coupling forward-propagating orthogonally-polarized low band electromagnetic waves into the dual band waveguide; a transition section coupled between the forward end of the high band feed section and the rearward end of the low band feed section, the transition section configured to couple high band electromagnetic waves from the high band waveguide to the dual band waveguide and to inhibit coupling from the low band vertical feed and the low band horizontal feed into backward-propagating low band electromagnetic waves; and a dual band waveguide horn tapering outward from a rearward end coupled to the forward end of the low band feed section to a forward end open to free space, the dual band waveguide horn configured to couple waves in the low wavelength band and the high wavelength band from the low band feed section to free space.