Performance Analysis of Soft Handoff in Networks Cdma-based Wireless Packet Voice/data

In this paper, we analyze and compare the performance of two soft handoff schemes for CDMA-based IMT-2000-like wireless packet voice/data networks. In the first scheme, handoff request of voice or data traffic is equally queued during the soft handoff, and in the second scheme, data traffic is forcibly dropped when the destination cell has no channel to handoff, and only the handoff requests of voice traffic are queued. Based on this scheme, voice traffic can maintain its QoS conditions such as handoff dropping rate. The performances of two schemes are analyzed using birthdeath process model. The models of voice and data traffic have Poisson arrival and exponential service time condition, and the parameters and distributions mentioned in the cdma2000 ITU IMT-2000 RTT candidate are considered. According to the performance analysis, the handoff refused probabilities of data traffic in two schemes are similar, but that of voice traffic in the second scheme is higher about a hundred time compared with the result of the first scheme.