Approximately Optimal Wireless Broadcasting

TL;DR

This paper introduces a wireless broadcast scheme that achieves near-optimal data rates within a constant gap of the theoretical maximum, leveraging relay quantization and advanced coding strategies.

Contribution

It presents a novel two-step scheme combining quantize-and-encode relaying with Marton coding, achieving near-capacity performance independent of channel specifics.

Findings

Achieves rates within a constant gap of the cut-set bound.

Combines discrete superposition network coding with Marton coding for Gaussian channels.

Operates effectively with relay quantization and receiver-centric coding strategies.

Abstract

We study a wireless broadcast network, where a single source reliably communicates independent messages to multiple destinations, with the aid of relays and cooperation between destinations. The wireless nature of the medium is captured by the broadcast nature of transmissions as well as the superposition of all transmit signals plus independent Gaussian noise at the received signal at any radio. We propose a scheme that can achieve rate tuples within a constant gap away from the cut-set bound, where the constant is independent of channel coefficients and power constraints. The proposed scheme operates in two steps. The inner code, in which the relays perform a quantize-and-encode operation, is constructed by lifting a scheme designed for a corresponding discrete superposition network. The outer code is a Marton code for the non-Gaussian vector broadcast channel induced by the relaying scheme, and is constructed by adopting a ``receiver-centric'' viewpoint.