The Construction And Routing Algorithm For Bluetooth Scatternet Based On Access Point

Bluetooth is an open specification for short-range wireless data and voice communication. Key features are robustness, low complexity, low power, and low cost.The construction of scatternet and routing are hotspots in Bluetooth in the world. Only the master and slave can communicate directly, the distance between two devices does not warrant the existence of a link, different form traditional ad-hoc network. Scatternet is composed of piconets, if too many piconets formed, the channel interference will degrade the system throughput significantly, so the piconet num is a main standard for scatternet formation algorithm. Two devices in communication range not always can communicate directly, so the protocol must guarantee a connected scatternet. The role of the bridge node is very important, because the data must be transmitted through the bridge node from one piconet to another, so the overload of the bridge node affects the performance of the scatternet extraordinary. We did the research under these principles, and proposed the new algorithm for scatternet construction. This paper first proposed a scatternet construction algorithm-FPFC, the difference between this algorithm and other algorithms is: the master can't connect with it's slaves after the topology structure formed, and not connect with it's slave immediately when found a slave. When the master arrive at the connection condition, it connects with it's slaves. The conditions are the master's slave reach a given number or can't found any device in a special time. The temporary master can find other device, or found by other device. We compared the FPFC algorithm with other algorithm in piconet num, link num, bridge node num, average role and construction time aspects, and analysed their performance, our algorithm is better than other algorithm.This paper improved the FPFC algorithm, proposed a scatternet construction based on access point. This algorithm partitions the piconets into different grade group according to the distance to the access point. The routing algorithm do not need too large buffer based on the scatternet structure, and when discover the route, do not need record the information of the node passed, so solving the problem that can't contain the whole routing information in the packet header.