Research On Coordination Algorithm For Wireless Sensor And Actor Network

Wireless sensor and actor network(WSAN)is a new extension of hybrid WSN in information acquisition and processing technology.Compared with traditional WSN,there are two new types of coordination named sensor-actor(SA)and actor-actor(AA)in WSAN.Most of typical protocols and algorithms for WSN may not be well-suited for the unique features and application requirements of WSAN.Based on optimization theory,swarm intelligence optimization and other calculating methods,some studies on coordination framework,mobile task assignment and network connectivity are carried on in this thesis by means of SA and AA coordination in WSAN to meet the requirementof real-time and energy-balancing characteristic.The important research results are asfollows:(1)Research on three layer coordination framework for WSAN based on hybrid communication,which complements the existing research literature.From the point of network energy balance,the article proposes a SA energy consump-tion model by analyzing three layer coordination framework mechanism in WSAN with considering network latency and network connectivity.The SA energy consumption is modeled as a nonlinear program to obtain optimal diameter of virtual grid,transmis-sion range of sensors and number of actors.Furthermore,a probability-based hybrid communication coordination framework is proposed.In the framework,the grid hires single hop communication and the cluster takes single/multiple hop hybrid communica-tion based on an optimal probability such that the whole network energy consumption more balanced.The performances of the proposed framework are validated through simulations in terms of network latency,energy efficient and lifetime.(2)Propose an event coalition based local AA task coordination scheme and a task assignment model for WSAN,which makes up the shortcoming of existing works.In view of the AA task coordination in WSAN,an event coalition based local A A coordination scheme is proposed.Unlike some existing task coordina-tion scheme,the scheme creates event coalition by exchanging event messages firstly,and then gets an optimal actor schedule by solving an optimal model in event coalition.In task assignment problem in WSAN,most of the existing works get an optimal as-signment model for the simpified problem which omits the mobility of actors or some others.The article model the problem with considering the TSP problem of actors,in order to minimize the maximum task completion time and balancing the energy of coordinated actors.By transfroming the multi-object optimization problem into a single-object one using ideal point,the near-optimum of each task operation would be scheduled with Quantum genetic algorithm.Simulation results have shown that the approach is effective in terms of real-time and energy balancing performance.(3)Research on connectivity restoration algorithms of broken WSAN sysmatically,which is the blind spot in the research area.Using the SA/AA coordination,we research the restoration scheme sysmatically on the following two as-pecs:(i)Restoring the connectivity of broken actor network.The article proposes a controlled move based algorithm to handle single failure,which balanced the restore overheads than some existing works in terms of whole and individual.In multple ac-tors failure,we model the problem as quadratically constrained mixed integer program by introducing the network flow theory firstly,and then design a distributed restora-tion scheme based on SA/AA coordination.To decreases the cascading movements of restoration,a local optimal relocation algorithm also be proposed.(ii)Reconnecting the broken WSAN optimally.Inspired by the idea of sensor and actor help each other,we model the problem as nonlinear program by introducing the network flow theory first,and then propose a three stage distributed restoration scheme.The last step of the al-gorithm hires Quantum genetic algorithm to solve the optimal model.To decrease the complexity of solving the model,we revised the model with some information collected by two stages,the optimal objects of revised model include the node energy balancing and depoly balancing.Balanced depoly actors in WSAN is important to the require-ment of real-time in SA coordination.MATLAB simulation results have shown that the proposed algorithm restores the connectivity of broken WSAN effectively.