Design of an Antenna with a Cosecant Square Radiation Pattern in Upward and Downward Directions

摘要

In the FWA system, base station antennas are planned to be mounted on telephone poles so as to achieve low cost. Since antenna position is relatively low, a cosecant square. radiation pattern in upward and downward directions is requested. Previously, patch antennas were employed. Those antennas were not suitable for wide frequency use. In this paper, a reflector antenna is employed. A single reflector curvature is shaped by the ray-tracing method for a TM01mode horn. Calculated results showed that radiation patterns were distorted by direct waves from a feed horn. In order to achieve satisfactory radiation patterns, a shaped dielectric lens was inserted in a feed horn. An excellent radiation pattern was ensured through calculations.