On the effectiveness of medium access with predictive collision avoidance

In factory automation where reliable low-delay communication is essential to maintain the required Quality of Service (QoS), efficient medium access schemes play quite an important role. Therefore we propose a centralized cognitive medium access method that utilizes prediction of white spaces to avoid collisions as well as improve utilization of transmission opportunities. Our simulation results show that under idealistic assumptions, CSMA extended by prediction outperforms the classical CSMA/CA by far. We demonstrate that even if the prediction is erroneous to some extent, the proposed algorithm (CSMA/PCA) shows remarkable improvements in terms of successful channel access, average queuing time per packet, as well as efficiency of spectrum utilization.