Research Of Blue-hoc Network Topology Construction Algorithm

Bluetooth is a global standard for short-range wireless data and voice communication. To its proximity-based wireless connectivity, it can quickly deploy the personal electronic equipments to Ad Hoc networks. As it is low consumption, low cost, high safety, Bluetooth is considered one of the promising technologies to be used in Ad Hoc networks. However, Because of the technical limitations and its own particular characteristics, the use of Bluetooth from Ad Hoc network also faces many challenges, including network formation.Ad Hoc network is a autonomous wireless network without fixed infrastructure and centralized admin is traction. It can provide a convenient support environment when the existing network infrastructure is not available. Currently, Ad Hoc network has been used widely in many fields. It will occupy an important position in the future communication technology field.In this thesis, the performance of Ad Hoc network based on Bluetooth is analyzed from the number of piconets, the load of bridge, the network form of devices, the communications links between devices, and some rules that can improve the performance of the Bluetooth Ad Hoc networks are generalized. A novel algorithm of network formation is proposed according to these rules.The algorithm is executed at each node with no prior knowledge of the network topology, thus being fully distributed. It first partitions the network into Bluetooth piconets. The master of each master has higher Bluetooth address. Then, these piconets are merged by the algorithm rules and interconnect the piconets into a connected scatter net.The algorithm preferential use devices of high Bluetooth address as the master and bridge, so it can effectively extend the life time of network. Meanwhile, the bridge strategy that the algorithm uses makes each bridge only connect two piconets and any two piconets are connected only through a bridge. So it can effectively reduce the load of bridge and redundancy among the piconets, which will enhance the network performance. Finally, the new algorithm is implemented in the Bluetooth module based on Ns2.The performance of the algorithm is analyzed according to the simulation experiments and some comparisons are made between the new algorithm and other related ones. In addition, the thesis brings forward the new research directions in the future.