Multicast Streaming over 3G Cellular Networks through Multi–Channel Transmissions: Proposals and Performance Evaluation

Abstract — In this paper, we propose a novel technique for the provisioning of multicast streaming flows in 3G W–CDMA cellular systems. Our focus here is on the transmission of a downlink multicast streaming flow to the interested users in a 3G cell. Over such networks, due to multi-user interference and channel impairments such as, e.g., deep fading phenomena, some error control features have to be provided in order to meet QoS guaran-tees. In previously proposed work [1], the wanted error resilience is achieved by exploiting common channel (CCH) transmissions and retransmitting lost packets according to multi-users HARQ schemes. Here, we propose to substitute ARQ error recovery with packet-based Forward Error Correction (FEC) [2] and with the transmission of a certain amount of redundancy over parallel common channels. In practice, we exploit the temporal diversity over multiple channels to strengthen the FEC scheme thereby increasing the QoS. In this way, every user can independently join the desired number of channels in order to optimize its own quality and without affecting the performance of the other users in the system. To increase error resilience, in every channel we exploit well-known packet-based Reed Solomon like coding techniques [2]. Moreover, appropriate time shifts of the information sent across the parallel CCH channels are also introduced to increase the robustness against error bursts. The performance evaluation is carried out through an analytical framework. The obtained results show the substantial benefits deriving from the usage of a multiple channel transmission technique. I