Extending the Scan Range of Phased Arrays Using Reconfigurable Antenna Elements

In this paper, a novel multi-mode antenna element for mm-wave communications is introduced. The antenna element can be integrated in array configurations so to achieve broad scan capability. While scanning, the gain degradation of ideal arrays follows a cos(theta(0)) behavior due to the element pattern. By using an antenna element with a reconfigurable pattern, it is possible to extend the scan range and increase the realized gain by using the radiating mode which covers the subspace of scanning. With the three-port antenna element proposed in this paper, this is possible by modifying the phase offset between the three ports. The antenna consists of a capacitively fed triangular patch loaded with a cross-shaped dielectric resonator. Three radiating modes can be generated introducing a 180 degrees phase offset across the input ports according to a specific configuration. In this way, the antenna beamwidth can be increased up to 135 degrees.