Reliability-constrained broadcast using network coding without feedback

Wireless broadcast has been widely utilized to deliver information of common interest to a large number of users. A major challenge for wireless broadcast is that wireless links are often unreliable. Further, it is not feasible for every receiver to acknowledge the correct reception of broadcasted packets. In this paper we investigate the use of wireless broadcast to deliver a given number of packets by a common transmitter to a given number of receivers, without feedback from the receivers, while meeting the reliability constraint, i.e. the probability that all receivers successfully receive all broadcasted packets is above a certain threshold. Rateless codes(RCs) technology is used to assist the broadcast. Performance analysis with the use of RCs is conducted. Simulations are conducted to validate the accuracy of the theoretical analysis. It is shown that the use of RCs can significantly reduce the number of transmissions required to meet the reliability constraint.