Performance of sectorised spatial multiplex systems

In an adaptive SDMA (space division multiple access) system users can share the same radio channel which is made possible by using adaptive array antennas at the base station site and forming multiple independent beams to serve the users. The spatial multiplexing on the air interface introduces a new dimension of parallelism into mobile communication systems and can be applied to FDMA, TDMA or CDMA systems to achieve capacity increase and/or interference reduction. Other more traditional approaches to achieve these goals include the introduction of microcells, more efficient coding schemes or sectorised cells. In a sectorised system multiple base stations (typically between 3 and 6) are installed at the cell site, each covering a specific sector of the cell. This also results in a reduction of interference and an overall capacity increase. Instead of comparing the gain that can be achieved with either method, we are interested in the performance of a system that combines both approaches, i.e. a sectorised spatial multiplex system.