A fast, flexible and accurate algorithm for shaping the 3D radiation pattern of an AAS

The use of Active Antenna Systems (AAS) in mobile communications has a number of advantages; the transmitted signal is focused, which results in a reduction of power required per connection, and the interference towards other users can be reduced, so the capacity of the system can be increased. One of the questions which arise in designing an AAS, is how to properly determine the current excitations. A lot of techniques are available in literature, but most of them make assumptions on the E-field patterns of the individual antenna elements, resulting in inaccurate results for beam steering. Techniques which do not impose any assumptions are often computational very intensive, resulting in an increased design time. This paper presents a fast, flexible and accurate algorithm to find the current excitations in order to shape the 3D radiation pattern of an arbitrary AAS.