  In this work we study the problem of hard-deadline constrained data
offloading in cellular networks. A single-Base-Station (BS)
single-frequency-channel downlink system is studied where users request the
same packet from the BS at the beginning of each time slot. Packets have a hard
deadline of one time slot. The slot is divided into two phases. Out of those
users having high channel gain allowing them to decode the packet in the first
phase, one is chosen to rebroadcast it to the remaining users in the second
phase. This gives the remaining users a second opportunity to potentially
decode this packet before the deadline passes. By this, the BS has offloaded
the packet to a `local network of users' which eliminates unnecessary BS
retransmissions. The problem is modeled as a rate-adaptation and scheduling
optimization problem to maximize the duration of this second phase such that
each user receives a certain percentage of the packets. We show that the
proposed algorithm has a polynomial complexity in the number of users with
optimal performance.
