Soft handover effects on downlink capacity-coverage trade-off in 3G WCDMA networks

摘要

It is well know that soft handover extends the coverage and increases uplink capacity in CDMA systems. Triggered by the asymmetric features of 3G Internet and multimedia services, in this paper, we analysed the soft handover effects on both downlink capacity and coverage. The relationship between the capacity and the coverage is also investigated. Results show that when the soft handover overhead is beyond a certain value, there is a trade-off between the capacity and coverage. We quantified and compared the soft handover effects on the capacity and the coverage with three different soft handover algorithms: distance-based, IS-95A, and UTRA algorithms. It is shown that, the performance of soft handover is closely related to the algorithm and parameters setting. Distance-based algorithm is not accurate for analysing coverage.