A multi-frequency base station antenna for complex cell configurations

To meet the complex cell configurations in 3G mobile communication systems, base station antennas are required to achieve multi-frequency operations. The electrical characteristics such as low sidelobe levels and electrical beam tilt capabilities are needed in these antennas. This paper clarifies the method used to achieve the electrical characteristics in the frequency band of 800 MHz to 2000 MHz. A linear array antenna is co-used for all the frequency bands. To design the above electrical characteristics, the radiation pattern synthesis technique is employed. To achieve the wide band low sidelobe characteristics, the adequate design frequency of the radiation pattern synthesis is derived. Moreover, the suitable antenna configuration for electrical beam tilt was clarified. Numerical radiation characteristics for the frequency range of 800 MHz to 2000 MHz and electrical beam tilt angle of 6 to 10 degrees are shown. Satisfactory characteristics are obtained.