INTERFERENCE ANALYSIS AND OPTIMIZATION ON 3G WCDMA NETWORK CASE OF HAWASSA CITY

Abstract

Hawassa is a city of tourism and education therefore city should have reliable and fast network access. Currently Ethiotelecom’s serves as a service provider in the city with CDMA2000, 2G GSM and 3G WCDMA wireless mobile network. 2G GSM and CDMA 2000 were the existing wireless service networks, in the last five years, 3G WCDMA wireless service is added. As an issue, there is still a lot of complain considering 3G WCDMA performance of network. We consider the high interference value taken from the ethiotelecom network management system and analyze problems, and solution for the problems is found by tuning Two main parameter of the network CPICH power and Antenna electrical tilt using a heuristic algorithm to define the optimum value for this specific case, The task is performed by measuring received total wideband power (RTWP), Radio access bearer (RAB) and radio resource controller (RRC) key performance indicator (KPI) values from the operation and maintenance center client system, then analysis is done using WINPROP simulating tool, to compare the real network current configuration parameter value with the parameter configuration that we suggested, using Ethiotelecom’s suggested KPI value as a base line. From the analysis we concluded that using the two parameters in combination enabled more improvements in both reductions of interference and network capacity gain comparing with the tuning parameter individually. Accordingly, interference could be minimized from −94.9𝑑𝐵𝑚 to −101.7𝑑𝐵𝑚 with network capacity gain of 4.04% fulfilling the required Eb/No and received power threshold and using common pilot indicator channel(CPICH) signal power of 7.5% of the total base transceiver station(BTS) power and electrical antenna down tilt by 2 degrees. Using common pilot indicator channel (CPICH) power and antenna tilt setups, the heuristic algorithm we use optimizes RTWP (uplink interference). The parameters chosen have a considerable impact on network capacity. We use WINPROP, a static universal mobile telecommunication system (UMTS) frequency division duplex (FDD) network simulator, to evaluate the network settings