Incorporating automatic repeat request and thresholds with variable complexity decoding algorithms over wireless networks: queuing analysis

Wireless networks are spreading very fast compared to wired-based networks because of its ease in installation, lower cost, reduced dependence on infrastructure and support for emerging mobile and sensing applications. Unfortunately, wireless channels are less efficient in carrying much of data. Moreover, they are characterised by having lower signal-to-noise ratio, resulting in more corrupted packets. Consequently, the performance of such networks may be severely affected due to invoking transmission control protocol (TCP) congestion algorithms whenever a packet is lost. The authors propose a novel queuing model that utilises Fano decoding and automatic repeat request (ARQ) to reduce the drawbacks of TCP in wireless networks. The proposed model describes how received packets are corrected based on Fano decoding mechanism and how the retransmission of corrupted packets is performed. The major aim of proposing this queuing model, when ARQ is totally incorporated, is to find a generic form expression for the average system capacity. The proposed model is validated through simulation in which the results show perfect agreement with those of the analytical model. The authors do not stop to this extent, but rather verify the correctness of the results through comparing them with those obtained in the previous work, where the mechanism of ARQ was completely neglected.