Solid state vs. Micro relay-switches employed in a circular switched parasitic array antenna

Beam steering and beam shaping with parasitic array antennas pose a suitable alternative to expensive phased array technology. Parasitic array antennas mainly consist of one or few active antenna elements which are surrounded by passive elements. The parasitic reactances of the passive elements can be controlled either by electronic tuning or switching. Doing this in a suitable way different antenna patterns can be produced. The presented circular switched parasitic array (CSPA) antennas consist of a circular array of passive monopoles and one active monopole in the center. The circumferential monopoles can be switched between a reflecting and a non-reflecting state by means of either micro-relay switches or solid state switches. In the reflecting state, high currents can be expected on the monopoles and the attached switching circuits. This may lead to a non-linear behavior of the solid state switches. It will be investigated, if the height of the radio frequency (RF) power which is supplied to the active center monopole has an impact on the radiation characteristics of the antenna.