Design of a Pattern Reconfigurable Switched Parasitic Array for Null Steering Application

With the evolution of technologies like cognitive communication and beam division multiple access, the scope of smart antennas is increasing. In this direction, electrically steerable parasitic array radiator (ESPAR) antennas are emerging as a substitute for traditional bulky phased arrays. This work proposes an 8-element switched parasitic array (SPA) which consists of an active octagonal patch antenna element surrounded by seven rectangular patches as parasitic elements. The elements are connected to the active patch using PIN diode switch. By turning ON or OFF different switch connected to the active element, the radiation pattern of the antenna can be altered. When three consecutive elements are connected to the active element at a time, the SPA yields a wide beam and a null in the opposite direction. By selecting different sets of three consecutive parasitic elements, the beam and the null can be steered.