Multihop Scatternet Formation Algorithm For Bluetooth Based On Dynamic Environment

Bluetooth is an open specification for short-range wireless data and voice communication .Its key features are low complexity, low power and low cost.Bluetooth has some common properties with ad hoc network like dynamic topology, mobile nodes, multihop and so on. But it has some different properties, for example, only the master and slave in same piconet can communicate directly, so two devices belonging to two different piconets do not link directly. The current version of bluetooth specification only supports constructing picnets, scheduling and routing of the packets, but does not provide any method for formation of scattemet. So the construction of scattemet is hotspots in the world. This paper describes a multihop scattemet formation algorithm based on dynamic environment. The algorithm is composed of two parts. One part describes a dynamic algorithm adapting to mobile nodes, which cooperates formation of scattemet with communication of nodes by the introduction of random state. Therefore, the bluetooth devices will return the state of constructing scattemet automatically when they finish their communication. Another presents adaptive scattemet formation algorithm based on the biggest weight of nodes, which includes devices discovery, formation of piconets and scattemet. It is executed at each node without prior knowledge of the network topology, thus being fully distributed.In this paper, the distributed algorithm for scattemet formation creates a connected mesh with multiple paths between any pair of nodes, thus achieving robustness. The algorithm presents three key innovative properties: 1) It is fully distributed and asynchronous; 2) It can be applied in a multihop environment; 3) It possesses self-healing which means that it can adapt to the topology variety arising from mobility of nodes or disappearing. We compared the algorithm with other algorithms in piconet num, average role, construction time and dynamic performance. The results manifest that the algorithm is better than other algorithm.