Impact of handover blocking on control load, capacity and coverage of W-CDMA downlink

The impact of handover blocking on the control load, capacity, and coverage of the W-CDMA downlink is studied using a dynamic system level simulator. The handover control mechanism, as defined by the 3GPP, was simulated in detail for a sectorized macro cell layout scenario. The results show that handover blocking increases the average holding time of a connection and the number of handover requests. The results also show that higher transmission power is required per channel to provide the desired coverage in both soft and hard handover cases, whereas the capacity is not reduced in the case of soft handover unless the blocking probability exceeds 0.8. The dynamic range required for transmission power control is also discussed.