A novel wideband circular polarization microstrip antenna - combination of different shaped antenna element

Although microstrip patch antennas have narrow VSWR and axial ratio bandwidth characteristics, they possess very attractive features, such as simple structure, low profile, light weight, low cost, etc. Satellite communication system mobile terminals are required to be small in size because of satellite antennas with high gain spot beams. As terminals become smaller, antennas for the terminals are also required to be low profile, light weight, simple structure, etc. Mobile terminal Earth station antennas, particularly for ship satellite communications systems, are mainly parabolic reflector antennas or helical array antennas. However, these antennas are too large for spot beam satellite antenna system. A novel low profile wideband circular polarization microstrip antenna is proposed. The antenna is composed of a combination of different shaped elements. As one example of the use of satellite communications system, the proposed antenna is applied to an INMARSAT Fleet F33 antenna. The calculated and measured results are demonstrated.