Modern Reflectarray Antennas: A Review of the Design, State-of-the-Art, and Research Challenges

As communication technology advances, high-gain antennas are being investigated for a variety of long-distance applications. One such high gain antenna is reflectarray, it has combined advantageous characteristics of a reflector and phased array antennas. However, to design the reflectarray antenna its phase range, bandwidth, gain, cross polarization and the side lobe levels must be in optimal range to meet the requirements for distant applications. In this article, we have reviewed various research works of reflectarray antenna and highlighted the techniques to develop an efficient high gain reflectarry antenna. Recently, for high gain applications, as per end user requirement, there is a need to vary the frequency and radiation characteristics in a controlled manner. This can be achieved by using reconfigurable reflectarray antennas. In this article, reconfigurable mechanisms and active elements used for reconfiguration are reviewed in detail. In the end of this survey, some of the works on reflectarray antenna which were published by the research society are compared, summarizing the important parameters such as operating frequency, phase range, gain bandwidth, peak gain, cross polarization levels, and side lobes.