QoS sensitivity to selected packet scheduling parameters in UTRAN

The sensitivity of quality of service (QoS) to a selection of UTRAN network parameters that packet scheduler (PS) applies in the control of radio resources was analyzed with simulations. The parameters were the minimum and maximum allowed bit rate, the inactivity timer, the maximum queuing time, and the minimum allocation time for dedicated channels. The analysis was performed with and without differentiated settings for distinct traffic priority classes. The quality of service was found especially sensitive to the inactivity timer, the minimum allowed bit rate, and the maximum allowed bit rate. The sea ice performance was also sensitive to the parameter differentiation indicating potentials for significant spectral efficiency gains if the parameters are properly tuned. The exploration of parameters in the study resulted in an increase of the user satisfaction ratio of the worst performing service from about 80% with the optimal un-differentiated settings to 97% using the best differentiated values. The corresponding spectral efficiency gain was 50%.