AF and DF Protocols in Cooperative Communications with MATLAB Implementation

This article explores AF (Amplify-and-Forward) and DF (Decode-and-Forward) protocols in cooperative communications, providing a comprehensive MATLAB implementation for complete simulation. The code includes modular functions for channel modeling, signal processing, and performance metrics calculation, enabling direct comparison between AF and DF protocols. We detail the simulation methodology where AF simply amplifies and retransmits received signals while DF decodes, re-encodes, and forwards messages, with implementations featuring error detection mechanisms and SNR-based amplification control. The analysis covers differences in error propagation, computational complexity, and spectral efficiency through BER (Bit Error Rate) and outage probability metrics. We interpret simulation results demonstrating trade-offs between implementation simplicity (AF) and error resilience (DF), along with practical applications in relay selection and power allocation scenarios. The discussion concludes with protocol advantages/disadvantages: AF's lower latency versus DF's better error performance, and guidelines for selecting appropriate protocols based on channel conditions, quality-of-service requirements, and hardware constraints.