Wideband circularly polarized antennas for satellite communications

Antennas for satellite communications have been dominated by reflectors, horns, waveguides and helix for many years. Recent years have seen a huge amount of publications on wideband circularly polarized (CP) antennas for satellite communications. This paper aims to provide a brief overview of the recent development in wideband CP antennas and arrays for satellite communications, as it is impossible to provide a comprehensive overview within 3 pages. This paper has two parts. In the first part, basic principles of CP antennas are introduced. Then, an overview of recent development in wideband CP antennas and arrays is given, and various techniques for bandwidth enhancement of CP antennas are discussed. In the second part, two examples of recent work at the University of Kent are discussed. These include a wideband CP antenna element using inverted-S element, and an ultra-wideband (UWB) CP array using the tightly-coupled array concept. A conclusion and future work are given at the end.