A Simplified Estimate-and-Forward Scheme for Relay Networks

Relay aided wireless transmission realizes extended coverage and increases capacity for wireless communication networks, especially for the TDD/FDD LTE-A system. The relay node processes the received signal from source under certain rules and forwards the signal to destination. Amplify-and-Forward (AF) and Decode-and-Forward (DF) are two of the conventional relay schemes commonly used and cited. Estimate-and-Forward is a well-know but much less studied approach. The basic idea is to forward an estimate version of original signal without hard decision. A soft symbol estimating approach by solving linear equation set structured with received symbol probabilities. This algorithm makes a least squares fit of the estimated symbol probabilities to a single shot noisy symbol a posteri probability (APP) model. In the simulation, we take frame error rate (FER) to demonstrate the proposed scheme outperforms existing relay schemes.