A Comparative Study of Amplify-and-Forward and Zero-Forcing Relaying with Different Power Constraints

Cooperating nodes in wireless networks need to be power-efficient because once they deployed, as in sensor networks, they might not be recharged or replaced. The choice of relaying technique, therefore, becomes a crucial design parameter. Our work provides a detailed comparative performance analysis of amplify-and-forward and zeroforcing relaying. Our results give valuable insights into the robustness of these two common relaying techniques under different assumptions on power constraints and channel conditions and can be used as a practical guideline in the choice of relaying techniques. Index Terms — Distributed space-time block coding, fading channels, amplify-and-forward relaying, zero-forcing relaying.