A dual-band, dual-orthogonally-polarized antenna element includes a dielectric substrate having a conductor layer that includes a square ring slot and a shorted square ring, with each having a pair of orthogonal feed points. The shorted square ring is fed with coaxial probe feeds, while the square ring slot feeds striplines terminated in open-circuited stubs for coupling energy to each pair of orthogonal feed points. The first and second stripline feeds are not coplanar in order that each stub terminates past a center point of the element. The square ring slot operates as a high frequency band radiator and the shorted square ring operates as a low frequency band radiator, and both bands radiate substantially simultaneous dual-orthogonally-polarized modes. The modes can be any combination of dual-Circular Polarization (CP) and dual-Linear Polarization (LP), depending on the geometry of the radiators.