Outage analysis of coded cooperation

TLDR

Cooperative communication, an emerging paradigm where mobiles share bandwidth and power, employs coded cooperation—channel‑coding based cooperation distinct from repetition methods—to improve overall performance. The study develops outage‑probability expressions for coded cooperation. Each node serves as source and relay under combined power and bandwidth limits, and numerical comparisons evaluate coded cooperation against repetition methods across different inter‑user and uplink channel conditions. The derived outage expressions demonstrate that coded cooperation achieves full diversity, distinguishes itself from decode‑and‑forward (which has diversity one), characterizes performance across rates, and provides more insightful bounds than prior BER results.

Abstract

Cooperative communication is an emerging paradigm where multiple mobiles share their resources (bandwidth and power) to achieve better overall performance. Coded cooperation is a mechanism where cooperation is combined with-and operates through-channel coding, as opposed to the repetition-based methods. This work develops expressions for outage probability of coded cooperation. In this work, each node acts as both a data source as well as a relay, i.e., only active (transmitting) nodes are available to assist other nodes, and each node operates under overall (source + relay) power and bandwidth constraints. Outage expressions confirm that full diversity is achieved by coded cooperation. This shows that despite superficial similarities, coded cooperation is distinct from decode-and-forward, which has been shown to have diversity one. The outage probability expressions developed in this work characterize coded performance at various rates. Furthermore, outage probabilities yield bounds that are arguably more insightful than the bit-error rate (BER) results previously available for coded cooperation. Numerical comparisons shed light on the relative merits of coded cooperation and various repetition-based methods, under various inter-user and uplink channel conditions.