| 摘要 |
PROBLEM TO BE SOLVED: To provide a base station antenna device which can simplify its constitution and also can reduce its cost and power consumption in a fast transmission mode by defining the horizontal antenna radiation characteristic as an adaptive array with the vertical antenna radiation characteristic defined as the fixed cosecant-squared characteristic respectively. SOLUTION: An adaptive array 14 is horizontally applied when a fast digital signal is transmitted via a base station antenna. Then a beam is generated in the direction of a desired wave 16 with the nulls formed in the directions of interference waves 17a and 17b respectively. Thus, the wave 16 can be separated from the waves 17a and 17b in terms of a space and accordingly the influences of both waves 17a and 17b can be reduced. Meanwhile, a cosecant- squared beam 15 that has an even distribution in a communication area is formed in regard to a vertical face. It's required to secure a fixed level of transmission/reception power between the far and near places for execution of a CDMA and therefore to essentially need the highly accurate transmission power control. In such cases, however, the even power can be transmitted and received by means of the beam 15. In other words, no highly accurate transmission power control is required. |
