Two hybrid ARQ algorithms for reliable multicast communications in UMTS networks

Multicast communications in wireless networks have attracted the interest of the scientific community, since many issues remain open. In this framework, our letter proposes two novel hybrid automatic repeat request (HARQ) algorithms for multicast communications in the UMTS radio link control (RLC) layer. The proposed algorithms exploit the channel autocorrelation in order to dynamically estimate the multicast users' channel conditions and thus reduce the mean service data unit (SDU) delay and increase the SDU throughput.