A fuzzy controller to improve CSMA/CA performance in IEEE 802.15.4 industrial wireless sensor networks

The IEEE 802.15.4 standard protocol for Wireless Sensor Networks (WSNs) offers several advantages, such as the low power consumption, which can also be applied in industrial environments. However, many researchers highlighted some limitations also. For example, the CSMA/CA algorithm, that manages the access to the medium, is a contention-based approach and, as a consequence, it is non deterministic. This paper proposes an approach that aspires to an efficient use of the available bandwidth reducing the number of collisions using a fuzzy logic controller that dynamically adjusts the Contention Window (CW) and the Backoff Exponent (BE) parameters of the CSMA/CA, taking into account the Throughput (TH) and the Workload (WL) of an industrial IEEE 802.15.4 WSN.