| 摘要 |
The invention relates to an antenna assembly (1) comprising at least one input port (10) and a plurality of antenna elements (20 - 24'). The plurality of antenna elements (20 - 24') is supplied by the at least one input port (10) via a circuitry (7). The antenna elements (20 - 24') are arranged along a circumference around an inner area (90) of the antenna assembly (1). At least two of the antenna elements (20 - 24') have distinct characteristic impedances. According to the invention, the impedance of an antenna element is varied with respect to that of another antenna element in order to achieve the desired spatial rf field distribution. The invention further relates to a radio transmitter (5) comprising at least one of the inventive antenna assemblies (1) as well as a RF source (11). In addition, the invention relates to a method for operating the inventive antenna assembly (1). |
