Approximately optimal broadcasting-cum-multicasting in wireless networks

We study a wireless broadcast-cum-multicast network, where a single source reliably communicates independent messages to multiple destinations, with the aid of relays. In addition, we assume there are nodes that demand all the messages at the source. We propose a compress-and-forward scheme that can achieve rates within a constant gap away from the cut-set bound. The proposed scheme operates in two steps: the inner code induces a broadcast channel with sufficient mutual information between the source and the destinations, and the outer code is basically a Marton code for broadcast channels. The inner code is constructed by lifting a scheme designed for a corresponding discrete superposition network.