UMTS capacity and planning issues

The spectral capacity limits of WBCDMA systems are difficult enough to predict in regular hexagonal networks where the interaction of link and system level often lead to nonintuitive results. Attempting to define the capacity in more realistic environments is complicated further as the variation of traffic and site distribution has a significant impact on overall capacity. To obtain capacity figures for the realistic environment requires the use of system simulations. This paper presents observations from applying 'static' system simulations across a realistic network deployment, when compared against capacity results obtained from a hexagonal network. The variation in capacity is explained as a result of non-uniform noise rise. Issues that a network operator must account for in network deployment are addressed.