Efficient Spurious Rejection and Null Steering Using Slot Antennas

Reconfigurable antennas are susceptible to spurious signal reception through feed lines, interconnects and connector transitions. In this letter, a two-slot antenna backed by a metal box is demonstrated, where such spurious signals are not picked up and, consequently, spurious rejection is very high. It is shown that the direction from which signals are strongly rejected is also switchable. Finally, a four-slot array for rejecting spurious signals over some angular range, rather than at a specific angle, is presented .