Typical behavior of relays in communication channels

Abstract

The typical behaviour of the relay-without-delay channel under LDPC coding and its multiple-unit generalisation, termed the relay array, is studied using methods of statistical echanics. A demodulate-and-forward strategy is analytically solved using the replica symmetric ansatz which is exact in the system studied at Nishimori’s temperature. In particular, the typical level of improvement in communication performance by relaying messages is shown in the case of small and large number of relay units.