Low sidelobe characteristics of a dual-frequency base station antenna in the case of electrical beam tilt use

To accommodate the remarkable increase in the numbers of mobile phone subscribers, plural systems and multi-frequency bands are being employed. In Japan, PDC (Personal Digital Cellular) systems use the frequency bands of 800 MHz and 1500 MHz. Typical electrical characteristics of base station antennas are low sidelobe levels and electrical beam tilt capabilities. In case of frequency sharing the 800 MHz and 1500 MHz bands, low sidelobe characteristics may be distorted. We discovered the suitable excitation coefficients to achieve low sidelobe characteristics. This paper showed the experimental results of sidelobe levels in the case of beam tilt use.