Aspects of radio network topology planning in cellular WCDMA

Abstract

Even through there are several studies in the literature regarding the topology of CDMA-based networks, there is a clear need for a solid analysis including extensive simulations and radio interface measurements of different radio network topologies and their impact on WCDMA radio network coverage and capacity. This thesis covers a thorough analysis of WCDMA radio network topology and its impact on the whole WCDMA radio network planning process. The scope is not just limited to a traditional planning approach, but also additional network elements such as repeater and services as location techniques are considered as a part of WCDMA radio network topology planning. In addition, methods for verifying the quality of the deployed radio network topology are presented. The information given to readers in this thesis should be most applicable for network operators (planners), as they should be able to plan networks which provide a high system capacity with a limited amount of radio equipment and efficient utilization of radio resources.

The content of this thesis has been divided into three parts. The first part concerns the assessment of different site and antenna configurations on the network coverage, system capacity, and expected functionality of WCDMA network. Fundamentally, the target of this part is to provide planning guidelines for optimization of the WCDMA radio network topology. Moreover, it assesses the impact of site locations, sectoring, and different antenna configurations on optimum radio network topology through the definition of coverage overlapping index. In addition, this part will further cover analysis of the impact of site locations and sector overlapping on the network performance. The most extensive research is performed regarding antenna downtilt that provides as an output valuable information of the selection of antenna downtilt angle for different cell types. Finally, some planning aspects are provided for site evolution from 3-sectored to 6-sectored sites.

The second part of the thesis introduces a method for evaluating the quality of topology planning through radio interface measurements. In addition, it offers an example of the functionality and performance of WCDMA radio network planning tool. The third part of the thesis addresses the impact of supplementary radio network element or functionalities on topology planning. Firstly, the impact of repeater deployment is studied in capacity-limited networks through simulations and radio interface measurements. Secondly, the effect of a mobile positioning method called cell ID+RTT is studied with respect to the topology planning process.