A SKEWED SLOT SCHEDULING APPROACH FOR REAL-TIME DATA TRANSMISSION IN INDUSTRIAL WIRELESS SENSOR NETWORKS

Improving the data transmission reliability of a time-constraint monitoring and control application in industry is a challenging task. Contemporary solutions are based on either Time Division Multiple Access (TDMA) or the hybrid model of TDMA and Carrier Sense Multiple Access (CSMA). However, most of them are burdened with a complex slot allocation scheme while others are vulnerable to the time varying nature of wireless links. Therefore, we propose a skewed slot scheduling approach that maintains a global time constraint in data delivery using a CSMA-base data transmission within a big-slot. All nodes at the same tree depth collectively allocate a big-slot and share it for data transmission reliability. The new approach is not only simple in design but also highly dependable against dynamically changing network topology. The approach also maximizes data aggregation and filtering, thus improving the balancing of energy consumption among sensor nodes.