Performance of real-time Multicast/Broadcast Services over TDD-OFDMA

Despite the inherent support, the QoS performance of real-time Multicast and Broadcast Service (MCBCS) such as Mobile TV over TDD-OFDMA remains unclear. From the network operator's perspective, it is of paramount concern to understand the quality of the broadcast/multicast video and how many (mobile TV) can be supported with the required quality, together with respective design options of the network. In this paper, we attempt to understand various operating constraints and interdependencies between layers such as video traffic types, MAC scheduling schemes, link budget and channel characteristics, modulation coding schemes, OFDMA resource allocation methods and so on. Due to limited space, this paper only presents a high-level analysis concerning some of the key design issues stated above. This provides a good pre deployment reference for future network operators who wish to consider TDD-OFDMA scheme, particularly in the format proposed in IEEE802.16e-2005 as solution for delivering MCBCS.