Quality of service management in wireless sensor networks for greenhouse environmental control

In order to reduce the impact of inherent network time-varying delay, packet loss, network congestion and other phenomena on control performance of the greenhouse environmental control system based on wireless sensor networks, the QoS management strategy based on Takagi-Sugeno fuzzy logic controller were proposed from the perspective of improving quality of service (QoS). The basic idea of the proposed QoS management strategy is to use deadline miss ratio as the evaluating index of the QoS and to adapt the sampling period of each sensor nodes by means of feedback control technology at run time so that the deadline miss ratio associated with the real-time data transmission from the sensor nodes to the actuator nodes is maintained at a pre-determined desired level and the required QoS can be achieved. Preliminary experimentations indicate the rationality, effectiveness and practicability of the proposed QoS management strategy. It can be effectively applied to the greenhouse, the field cropland, and the nursery garden, etc. This research contributes to the exploration on how to improve the application level of wireless sensor networks in facility agriculture.