Low Complexity Amplify and Forward Relaying without Channel Amplitude Estimation

We propose a low-complexity amplify and forward relaying scheme that avoids channel amplitude estimations by combining the signals associated with the individual relays into an equal gain combiner (EGC). An approximate performance analysis of such scheme is conducted using the well-known moments-based approach. Additionally, motivated by the so-called EGC´s combining loss, we propose an algorithmic method that sorts out the weakest relayed branches (in a long-term sense), aiming at activating only the relays that substantially contribute to the overall system performance.