Reliable Broadcast to A User Group with Limited Source Transmissions

TL;DR

This paper introduces a two-phase coded broadcast scheme that minimizes source transmissions and power consumption by leveraging cooperative peer-to-peer re-encoding, improving efficiency over traditional methods.

Contribution

It proposes a novel two-phase scheme using BATS codes and cooperative re-encoding to reduce source transmissions and power use in reliable broadcast scenarios.

Findings

Reduces total retransmissions compared to traditional single-phase broadcast.

Significantly lowers power consumption at the source node.

Provides analytical derivation of rank distribution for optimal code design.

Abstract

In order to reduce the number of retransmissions and save power for the source node, we propose a two-phase coded scheme to achieve reliable broadcast from the source to a group of users with minimal source transmissions. In the first phase, the information packets are encoded with batched sparse (BATS) code, which are then broadcasted by the source node until the file can be cooperatively decoded by the user group. In the second phase, each user broadcasts the re-encoded packets to its peers based on their respective received packets from the first phase, so that the file can be decoded by each individual user. The performance of the proposed scheme is analyzed and the rank distribution at the moment of decoding is derived, which is used as input for designing the optimal BATS code. Simulation results show that the proposed scheme can reduce the total number of retransmissions compared with the traditional single-phase broadcast with optimal erasure codes. Furthermore, since a large number of transmissions are shifted from the source node to the users, power consumptions at the source node is significantly reduced.