Multi-objective optimization control in monitoring system for facility agriculture based on wireless sensor network

In order to reduce the impact of inherent network time-varying transmission delay, packet loss and other phenomena on performance of the remote monitoring system based on wireless sensor network, a kind of multi-objective optimization control strategy based on network quality of service (QoS) management is proposed from the perspective of improving the overall system performance. For the data transmission between sensor nodes and sink node, the optimization control strategy takes deadline miss ratio as the QoS evaluation criteria, and utilizes the PID controller to calculate the network bandwidth needs of all sensor nodes. On this basis, by solving the optimization problem which contains multiple objectives, the packet sending period of all sensor nodes is adjusted so that the network bandwidth allocation can adapt to the QoS changes, the QoS is maintained at a predetermined desired level and other performance criteria are achieved. Preliminary experimentations indicate that the optimization control strategy is reasonable, effective and practical, which can be widely used in greenhouses, croplands, nurseries, etc.