MBMS Handover Control for Efficient Multicasting in IP-Based 3G Mobile Networks

Handover Control in a cellular infrastructure aims to provide continuity of mobile services to a user traveling over cell boundaries. So far, Handover Control is considered only between cells supporting the service using Dedicated Resources and the handover decision making is based on a comparison between an observed signal strength value and a predetermined threshold chosen in a manner so as to maximize the overall system capacity. With the introduction of Multimedia Broadcast Multicast Service (MBMS), for radio efficiency reasons, one cell can use either Common or Dedicated resources for the distribution of the same content in a Cell. Thus, the mobile users that are on the move may have to deal with dynamic changes of network resources when crossing the cell edge, introducing new types of handovers (MBMS Handovers). Using the current Handover Algorithm when an MBMS Handover is executing will not be so efficient. For the efficient execution of these new types of handover a different approach has to be followed. This paper proposes a new Handover Algorithm which efficiently maximizes the overall system capacity when mobile MBMS users have to deal with these new types of handovers.