Patch antenna element

An antenna element for transmission and/or reception of signals within a frequency band, the antenna element comprising a ground plane, a patch radiator, a connection point for connection of the antenna element to a feed network having a terminating impedance, and a probe having two ends, the probe being located between the ground plane and the patch radiator, the patch radiator being disposed in a parallel relationship with the ground plane to form a resonant cavity between the patch radiator and the ground plane,

• wherein the antenna element comprises a transmission line disposed in a parallel relationship with the ground plane, wherein the transmission line is connected to an end of the probe and arranged to have a length such that an impedance at said end of the probe is transformed, and
• wherein the transmission line is contained within the resonant cavity between the patch radiator and the ground plane,
• wherein the antenna element further comprises a matching stub of a determined length, one end of the matching stub being connected to the transmission line at the connection point,
• wherein the other end of the matching stub from the end connected to the transmission line is open circuit with respect to the ground plane,
• and wherein, wherein the antenna element further comprises a conductive barrier connected to the ground plane and perpendicular to the ground plane, the conductive barrier being arranged to form walls of enclosure defining the resonant cavity, the enclosure having a top face defined by the patch radiator and a bottom face defined by the ground plane, there being a non-conductive gap provided between the periphery of the patch radiator and the barrier.