Research On The Coordination Mechanism Between Sensors And Actors In WSANs

Wireless sensor and actor networks (WSANs) are composed of a large number of resource-limited sensors and a small number of resource-rich actors to perform distributed sensing and acting tasks. Sensors gather information about the physical phenomenon, while actors take decisions and then perform appropriate actions upon the environment. There are many potential applications of WSANs, such as battlefield surveillance and microclimate control in buildings, nuclear, biological and chemical attack detection, industrial control, home automation and environmental monitoring.To accomplish effective sensing and acting tasks, efficient coordination mechanisms of sensor-sensor, sensor-actor and actor-actor are required. In this paper, a single-actor selection algorithms for WSANs are addressed from hops and energy constraints. The corresponding optimal solution HBMECT (Hop-Bound and Minimum Energy Cost Tree) is determined by integer linear programming (ILP).And then a distributed approximate algorithm of HBMECT is provided for coordination of sensors-actor based on an improved geographical clustering paradigm in which cluster formation is formed by some minimum cost tree.On the basis of single-actor coordination, we consider the situation of multi-actors selection. By recomputing the energy consumption to every actor on every relay sensor node, we decide a right next relay node and a appropriate new target actor as the root of MCT(Minimum Cost Tree). We call this algorithm DHBAECCT(Distributed Hop-Bounded and Adaptive Energy Consumption Cost Tree) and give the corresponding optimal solution by ILP. And a distributed approximate algorithm of DHBAMECT is provided for coordination of sensors-actors.In the performance evaluation, the approximate algorithm of HBMECT is compared with MECT (Minimum Energy Cost Tree) and MPCT (Minimum Path Cost Tree) algorithms.At the same time, the approximat algorithm of DHBACCT is compared with the traditional GFR(Greedy Forwarding Routing) algorithm. The simple analysis of two algorithms is give at last.