articipating in soft handover do not necessary need to be under the same RNC. The SHO is a necessary and interference reducing feature of the WCDMA system. However, if the SHO area is more than 40° % of the dominance area it is consuming a large amount of lub, code and NodeB resources, and SO should be limited. On the other hand, if the cell separation does not leave much overlap and the SHO area is less than 30 % of the cell dominance area the risk of having coverage holes increases. The lack of cell overlap increases the transmit powers when the UE is close to the cell edge, compared to the situation where the mobile is connected to two cells where SHO gain allows transmit powers to be reduced. The third problem relates to small SHO areas where there is a risk taht the SHO will fail. If the serving cell Ec/1 reduces very rapidly when the new cell enters the reporting range, there is a risk that the SHO will fail due to the serving link failing SO fast that the UE measurement reports are not received by the WBTS and the active set update command is not received by the UE. As a general guideline the SHO area should be around 30-40 % of cell dominance area. Soft handover takes place when the radio conditions are such taht the mobile moves in the network and the radio conditions change. The mobile is measures and evaluates the situation according to the Radio Network Planning and Optimisation measurement control information. In the measurement control message the mobile is informed of the measurements that need to be performed and the conditions that require the mobile to report the situation to the network. If the triggering conditions are fulfilled, the mobile sends a measurement report to the network. In SIB11/12 or in the measurement control message the network sends information needed to measure the neighbouring cells. In this case triggering conditions are fulfilled and the mobile sends a measurement report requesting an active set update. The measurement control message contains two different types of inform