Performance Evaluation of multi-hop Detect-and-Forward and Amplify-and-Forward wireless transmission systems

In this paper we propose a new scheme for multi-hop forwarding in wireless networks. This new scheme is based on detection and forwarding of the received messages at the physical layer, without further processing at the higher layers. We derive a new expression for the symbol error rate in this proposed multi-hop detect-and-forward network by modeling the transmission line as a Markov Chain. The derived expression is quite general with respect to the (de) modulation scheme and the channel model. We compare the error rate performance of the proposed multi-hop detect-and-forward scheme with the earlier in the literature proposed multi-hop amplify and forward scheme. For the case of slow-varying flat-fading Rayleigh channels, our analytical and simulation results show that these two systems have surprisingly close performance at a wide range of signal to noise ratios.