On capacity and emission improvements by smart antennas in mixed traffic UMTS networks

Apart from providing high system capacity it is essential for mobile communications systems as UMTS to operate with low electromagnetic emission. Smart antennas are one promising technology to establish exposure reduction while upholding system capacity requirements. In this context, the main objective of this paper is to assess the performance improvements of practically applicable beamforming concepts for UMTS networks. The concepts illuminated are fixed as well as adaptive beamforming. To obtain suitable assessments we especially attend three essential aspects. First, proper SINR modelling is considered including spatially formed inter-/intra-cell interference as well as pilot pollution prevailing UMTS networks. Special interest is secondly given on the interaction between UMTS specific radio-resource management algorithms as power-/load control and the smart antenna concepts considered. Finally, we investigate mixed data rate traffic which is expected for UMTS. The simulations are carried out utilizing a combination of UMTS physical and dynamic system level simulators.