Enhanced UMTS traffic generation and activity models are described and characterised, based on population and service penetration values. An offices scenario was defined with a selection of relevant applications. ON/OFF states have been characterised by appropriate statistical distributions, and parameters for source traffic modelling have been presented. In the office scenario, if the cell radius decreases and the number of BSs increases, the blocking probability decreases with a linear trend. One concludes that the supported traffic and the corresponding throughput significantly increase when the cell radius decreases. However, increasing system capacity by decreasing the cell radius, causes an increase in the intensity of handovers and a decrease in the throughput per BS. Hence, optimum values for the coverage distance will correspond to higher cell radius. Delay and delay variation are not a limitation.