WCDMA common pilot power control with cost function minimization

The paper validates the feasibility of automating the setting of common pilot power in a WCDMA radio network. The pilot automation improves operability of the network and it is implemented with control software aimed at load balancing while also assuring pilot coverage. The pilot power of a cell is periodically updated by a gradient descent method that minimizes a cost function. The cost function describes differences in load between the cell and neighboring cells and pilot coverage that terminals of the cell measure. The approach is validated using a dynamic WCDMA system simulator with a deployment of macrocells and microcells on a city region whose measured propagation characteristics are incorporated into the model. The results show that the proposed control method slightly improves the air interface performance measured as a function of packet throughput.