A CYLINDRICAL SHAPED-REFLECTOR ANTENNA WITH A LINEAR FEED ARRAY FOR SHAPING COMPLEX BEAM PATTERNS

In this paper, we present a cylindrical shaped-reflector antenna which is spatially fed by an off-set linear feed array to form complex beam patterns. The linear feed array consists of twelve microstrip patch elements and forms a flat-topped beam pattern with a beam-width of ±45° in the azimuth plane. The vertical curve on the cylindrical reflector with the linear feed array is shaped to form a cosecant beam pattern within the range of -5° to -25° in the elevation plane. By using the proposed design procedure to form complex beam patterns, a hybrid antenna with a cylindrical reflector aperture of 140 cm x 50 is designed to be operated within the IMT 2000 service band, and a prototype antenna is also fabricated. Its electrical performance is measured and compared with simulation results.