OFDM-Based Semi-Soft Handover for High Data Rate Services

Various approaches for analyzing handover have been developed to guarantee the QoS (Quality of Service) of multimedia services over mobile communication networks. However, no framework for multicarrier-based broadband systems, such as MC-CDMA (Multi-Carrier Code Division Multiple Access) or OFDMA (Orthogonal Frequency Division Multiple Access) is available, from the perspective of link capacity. This paper presents a handover technique, referred to as semi-soft handover utilizing macro diversity, which permits both hard and soft handover advantages for services over multicarrier-based broadband networks to be retained. A theoretical analysis is then performed to measure the handover gain over the forward link in terms of an outage probability. The simulation data verifies that the semi-soft handover outperforms other traditional handover techniques, in particular, for high data rate services.