Automatic UMTS system resource dimensioning based on service traffic analysis

Mobile network operators base their TDM network capacity dimensioning on Erlang B models. This approach was valid in legacy GSM networks. However, current Universal Mobile Telecommunications System networks deal with different resource consumption services such as voice, video call or data, and different limiting resources such as baseband processing capacity, transmission link capacity to the RNC, or spreading code tree. Operators need models to decide which resource must be upgraded, according to the demand of the services, in order to achieve expected overall service accessibility (i.e., the complementary of blocking probability). Network operation requires detecting when degradation is due to a lack of resources or to a hardware malfunction. Also, when operators need to prevent blockage in a high-capacity demanding event (for which they only have traffic predictions for each service) it is far from trivial to dimension resources. We have implemented a Kaufman Roberts approach to characterize the multiservice resource demand. Using real reported traffic Key Performance Indicators to calibrate the model, an estimated accessibility is obtained at a per-resource level and combined to find global estimated accessibility. The proposed model is intended to assist network operation, estimating individual resource shortage, differentiating congestion from hardware failures, and predicting the necessary resources to be deployed to tackle a high-capacity demanding event.