Distortion limited amplify-and-forward relat networks and the epsilon-critical phase transition

Conference item

We study amplify-and-forward (AF) relay networks operating with source and relay amplifier distortion, where the distortion dominates the noise power. The diversity order is shown to be 0 for fixed-gain (FG) and 1 for variable-gain (VG) if distortion occurs at the relay; if distortion occurs only at the source, the diversity order will be 1 for both. With εβ = N0/ηβ (N0 the noise power, ηβ the distortion power at node β ∈ {S,R}, the source or relay), we demonstrate the emergence of what we call an ε-critical signal-to-noise plus distortion ratio (SNDR) threshold (a threshold that emerges when min{εβ} becomes small) for both forwarding protocols. We show that crossing this threshold in distortion limited regions will cause a phase transition (a dramatic drop) in the network’s outage probability. Thus, small reductions in the required end-to-end transmission rate can have significant reductions in the network’s outage probability.

Authors: Simmons, D; Coon, J

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Institute of Electrical and Electronics Engineers
• Host title: IEEE International Conference on Communications, 2017. ICC '17.
• Journal: IEEE International Conference on Communications, 2017. ICC '17.
• Publication date: 2017-07-01
• Acceptance date: 2017-01-27
• DOI: 10.1109/ICC.2017.7996522
• EISSN: 1938-1883
• Keywords: Outage probability; OFDM; Relay; Amplify-and-forward; Nonlinear; Distortion limitation