Fountain Codes with Superposition Feedback

Abstract

In the broadcast scenario, how to use feedback chan-nel is always a hot research topic. If receivers have independent feedback channel, it will waste a lot of frequency or time slot resources. Whereas, if all receivers share the same channel to transmit feedback message, a feedback storm will occur, which causes the transmitter to be unable to confirm which receiver has successfully received the information packet. In order to make use of receivers feedback message, in this paper, we propose a novel fountain codes based on superposition feedback. By analyzing the intensity of received superposition feedback signal, the probability of information packet can be recovered by all receivers is calculated, which can be used to adjust the selection probability of information packets. Simulation results show that the proposed fountain codes in broadcast scenario can significantly reduce the overhead compared to traditional fountain codes.