| 摘要 |
The invention relates to an array antenna (1) comprising a number of antenna elements (3.1-3.8, 4.1-4.8). The antenna elements are divided up into a first group of at least two antenna elements (3.1, 3.3, 3.5, 3.7, 4.1, 4.3, 4.5, 4.7), having a first main lobe direction, and a second group of at least two antenna elements (3.2, 3.4, 3.6, 3.8, 4.2, 4.4, 4.6, 4.8), having a second main lobe direction. In order to produce a number of fixed antenna patterns of an attractive type, between which the array antenna can be switched, the array antenna is provided, according to the invention, with a switchable phase network (37) and a specific feed network (21, 22). The feed network is divided up, between the feedpoint (20) and the antenna elements, into a first branching network (21) for feeding the said first group of antenna elements, and a second branching network (22) for feeding the said second group of antenna elements. The first branching network is arranged to initiate essentially the same phase shift between the feedpoint and the respective antenna elements within the first group. The second branching network is arranged to initiate essentially the same phase shift between the feedpoint and the respective antenna elements within the second group. The array antenna is suitable, for example, as a base station antenna in a mobile telephone system. <IMAGE> |
