Automatic optimisation for UMTS indoor coverage using distributed antenna systems

With the shift of focus from 2G to 3G systems, there is a tendency to evolve towards picocellular environments, which can provide coverage to hotspots inside buildings. At the same time, interference management has become a key issue, since this has significant impact on coverage of the indoor cell, as well as on nearby macro/micro cells. Given the large number of optimising parameters in a WCDMA based system, and their complex interdependence, a network plan derived on the basis of an operator´s experience alone becomes less reliable and more time-consuming, if not impossible. On the other hand, radio planning and system optimisation, aided by automated tools, is not only more efficient and cost-effective, but may become the only option as 3G systems mature. We have focussed on designing an automatic optimisation algorithm for in-building radio networks, with some discussion on the essential factors to be considered for this purpose.