Compute-remap-compress-and-forward for limited backhaul uplink multicell processing

Abstract

We study the transmission over a cloud radio access network in which multiple base stations (BS) are connected to a central processor (CP) via finite-capacity backhaul links. We propose a lattice-based coding scheme in which the BSs decode linear combinations of the transmitted messages, in the spirit of Compute-and-Forward (CoF), but differs from it essentially in that the decoded equations are remapped to linear combinations of the channel input symbols, sent compressed in a lossy manner to the CP, and are not required to be linearly independent. Also, by opposition to the standard CoF, an appropriate multi-user decoder is utilized to recover the sent messages. This novel scheme differs from both classical Compute-and-Forward and Successive Wyner-Ziv (SWZ) and it is shown to outperform both schemes, in certain regimes, through some numerical examples.