Date Added: Oct 2012
Upcoming LTE networks have basically two different modes for scheduling data in the down-link by the base station. Dynamic scheduling brings the advantage of exploiting instantaneous channel state information while it puts on the other hand a significant burden on the system in terms of overhead and computation requirements. Especially for small packets that show up periodically, the overhead is typically too high. Therefore, the base station can serve such packet flows by the semi-persistent scheduling mode. In this mode, a certain resource allocation is fixed to a periodic schedule. While this does not allow any longer exploiting instantaneous channel states, it requires much less overhead.