Active scan-beam reflectarray antenna loaded with tunable capacitor

In this paper, the design concept of an active reconfigurable reflectarray antenna has been proposed and tested. The elementary radiators are hollow patch antennas loaded with varactor-diode device which its reflected phase can be varied. This phase alteration is based on the variation of the diode capacitance which can be achieved by varying the biasing voltage of the active varactor device. By activating these varactor devices, the phase of each antenna element in the array configuration can be adopted dynamically and consequently its radiation beam can be reconfigured. The advantage above the MEMS switches is complexity of the integration and continues beam scanning capability. The reflectarray incorporating active elements has been built and tested at 6.0GHz. The performance of the proposed active antenna is excellent which pioneers design of arbitrarily reconfigurable antennas.