Research Of Multicast Broadcast Single Frequency Network Wireless Resource Management Strategy

Multicast and Broadcast Single Frequency Network is a new transmission mode introduced by Third Generation Partnership in the Evolved Multicast and Broadcast Multimedia Service. In the MBSFN, every cell uses the same frequency at the same time to transmit the same service, so the user can receive MBSFN’s diversity gain from a plurality of cells, which thus effectively solves some problems in Multicast and Broadcast Multimedia service such as the insufficient utilization of radio resources, instability service reception and blind coverage, greatly increasing spectrum efficiency and coverage ratio.However, MBSFN as a way to enhance multicast transmission, enhanced the performance of multicast traffic transmission, which is still subject to the worst channel quality user in the allocation of resources, making users in good channel quality cannot make full use of channels. In MBSFN, all MBSFN cells use the same resource at the same time to send multicast traffic, if allocating multicast resources according to the worst channel quality, some users in poor channel may affect the entire SFN resources distribution in MBSFN, and users in good condition can not make full use of channel resources, and even excessivly increase the load of other cells, affecting the quality of service to other users at the cell.To solve this problem, this thesis presents a collaboration strategy based on the device-to-device technology in MBSFN. The strategy guarantees the quality of the multicast server for users in poor channel by using D2 D technology.So the MBSFN multicast resource scheduling can make full use of radio resource without the restrictions of the worst user, and when there is a user in poor channel which can be guaranteed by the D2 D technology to successfully receive the multicast data with D2 D relay. So the strategy can achieve full use of multicast channel resources and guarantee the need of users.In addition, according to the transmission features of the MBSFN and 3GPP standards, MBSFN user can receive multicast traffic in idle state. Therefore, when the idle state multicast user moves from the MBSFN cell to the common cell, business continuity issues need to be considered. Secondly, with the diversity gain characteristics in MBSFN, the cell cannot recognize the multicast channel quality is good or poor with using the cell reference signal strength, common cell reselection method has not been sufficient to guarantee the effectiveness of its re-election.Therefore, in order to ensure the business continuity when the user in Idle state moves from the MBSFN edge to the non-MBSFN cell and improve the performance of cell reselection, a cell reselection strategy at MBSFN edge is proposed. This strategy uses MBSFN reference signal instead of a cell reference signal, and decide the switch time based on the measured multicast channel quality, which makes full use of the multicast resources, decreases unnecessary cell reselection and ensures service continuity of the user at the edge of MBSFN.