Point-to-Multipoint Multimedia Broadcast Multicast Service (MBMS) Performance over HSDPA

The aim of this paper is to evaluate the system level performance of point-to-multipoint (p-t-m) multimedia broadcast multicast service (MBMS) performance over high speed downlink packet access (HSDPA) scheme. MBMS was introduced in 3GPP Release 6 to provide efficient transmission mode for multimedia delivery and Point-to-Multipoint transmission through secondary common control physical channel (S-CCPCH) or point-to-point (p-t-p) transmission using e.g. HSDPA. As S-CCPCH lacks of power control it would seem feasible to provide p-t-m transmission over HSDPA as it supports flexible link adaptation methods. Usage of HSDPA for p-t-m MBMS delivery could be useful from link efficiency point of view as well as it would give flexibility to allocate capacity between MBMS and other services. In this paper p-t-m MBMS over HSDPA scheme is presented and its performance is evaluated with dynamic system level simulations. P-t-m MBMS over HSDPA scheme without any link adaptation is compared to a method where number of transmissions is changed based on UE reported feedback. Although link adaptation performance in p-t-m transmission is found to be heavily dependent on number of subscribers in the network, achieved gains ranges from 25% to 70 % in terms of saved transmission resources.