Research And Application Of Adaptive QoS Routing Algorithm In Wireless Sensor Networks

Wireless sensor network is a highly developed and universally acknowledged new network technology in recent years, integrates sensors, embedded computing, network communication, distributed information processing and other technologies, and has self-organization, adaptive, data-centered and other characteristics. Wireless sensor network uses many micro-sensor nodes to real-time monitor, aware and collect all kinds of environment and monitoring objects'information via self-organization network, it can be widely applied in environment monitoring, military and national defense, health care, traffic safety management and other domains, and it's a hot international research topic in the field of information. Sensor nodes have weak communication capability and limited power due to their small size, which makes the performance of routing algorithm essential to wireless sensor network. Routing algorithm is not only the basis of realizing energy balance and keeping network connective, but also the key to improve the quality of service and prolong the network lifetime.On the basis of project requirement, this paper focuses on research and application of QoS(Quality of Service)routing algorithm of wireless sensor networks. The application environment of wireless sensor network is various, so QoS parameters changes with the dynamic change of environment. But the most existing QoS routing algorithms were theoretical study, took ideal outdoor environment as research background, had limited adaptive ability, and performed poor results in practical application. Based on this, oriented on practical application requirements, an entropy-based adaptive QoS routing (EAQR) algorithm for wireless sensor networks was proposed in this paper. In the algorithm, the routing establishment process was abstracted as multi-attributes decision-making, nodes'load, average energy potential, time-delay were selected as QoS evaluation attributes, multi-attributes evaluation model was made, original data was standardized processed to eliminate the contradiction between attributes, attribute weights were adaptively determined by the method of entropy integrated with the change of QoS parameters, and then a sensor node can choose an optimal node to relay the data. Simulation results on OMNeT++ platform shows that every QoS parameter of EAQR performs better with the change of environment than classic QoS routing algorithms. It proves that EAQR algorithm can effectively adapt to the dynamic change of environment, it has better adaptive ability and shows better expandability when network scale expands.There are walls, doors and other obstacles, human removing, doors and windows switching, and other random variations in buildings, which is a typical dynamic changing environment. EAQR algorithm was applied in building environment in this paper, environment monitoring system based on wireless sensor network was designed and built, entropy-based adaptive QoS routing strategy was integrated in the system to test the algorithm performance. Experiment results shows that EAQR algorithm performs well, has better adaptive ability oriented on complex and changeable building environment, and can satisfy the QoS requirement of building monitoring.