Influence of the user mobility on the spatial multiplex gain of an adaptive SDMA system

Adaptive space division multiple access (A-SDMA) is a new technology for mobile communication systems with which the capacity can be increased and cochannel interference can be reduced. It is based on the application of an adaptive array antenna at the base station site which is used to form multiple independent beams per traffic channel. Each of these beams is used to support a connection with a mobile station, i.e., multiple mobile users can be served in the same traffic channel, and the capacity of the base station is increased. To evaluate the benefits of A-SDMA in terms of capacity increase, an analysis is presented which permits to analyse the spatial multiplex gain of an A-SDMA system taking into account the user mobility. Additionally, various other performance parameters of particular interest for the design of a cellular system with A-SDMA technology are derived. Furthermore, an example is given, where from a cellular scenario a user density distribution is derived which is then used as an input for the analysis derived in the first part of the paper