The effect of electrical and mechanical antenna down-tilting in UMTS networks

In an interference-limited CDMA system, network planning and the optimal installation of infrastructure components are important issues. This is not only to increase system capacity but also to allow for a smooth network operation. Whereas the Node B locations can hardly be changed, modern antennas provide adaptation mechanisms with which the antenna down-tilt angle can be adapted to the various needs of the network. This is dependent on the locations of the base station sites, the resulting cell sizes, and the current traffic situations. The simulations presented in this paper show basic effects on network coverage and capacity due to changes in the antenna down-tilt angle configuration. It is differed between mechanical and electrical adjustment of the down-tilt resulting in slightly different antenna characteristics.