Packet Retransmission and Delay Assessment of Spatial Diversity-Enabled Reliable Wireless Industrial Networks

Most important parameters in Industrial Communication Networks are packet delay and reliability. In this paper, packet delay and retransmission characteristics of Multiple Input Multiple Output (MIMO)-enabled wireless industrial networks using a simple Spatial-Diversity (SD) scheme in physical layer has been analyzed. Results show that due to the low Signal to Noise Ratio (SNR) in factory environment, simple modulation schemes with lower spectral efficiency have better delay performance and the default retry-limit parameter of 7 will satisfy the reliability of about 100%. Otherwise, the delay will be highly sensitive to SNR, packet payload, number of competing nodes and other parameters.