The Research On Bluetooth Simulation Tools Based On NS

Bluetooth which is a global standard for short-range wireless communication is considered as one of the promising technologies to be used in Ad hoc networks for its low cost, low energy consume and easy to form network. However, the formation, schedule and routing of Bluetooth network are different from tradition wireless networks for the constraints and some characteristics of Bluetooth technology itself. Computer simulation methods are widely used among wireless network research for its advantages of controllabe, reappearance and extensible. So, it has great significance to study and develop a Bluetooth simulation environment which adapts to all network scene.Based on Bluetooth architecture and the splitted object model of NS, Bluetooth network simulation tool is our main study content. A Bluetooth simulation environment is improved and extended. And its ability to support dynamic topology formation is emphasized.Based on the prototype of BlueHoc which is a Bluetooth simulation modual upon NS, the Bluetooth node structure is modified and extended from two sides. First, for its disadvantages in dynamic networking, the separated structure of master and slave is merged. And a new Bluetooth node structure which has the ability of dynamic role changing is got. Second, for its insufficiencies in nodes controlling, we add a new module BTExtend above the BTHost modual, through which can controll the Bluetooth nodes behaviour flexibly. Under the new Bluetooth node structure, by handling all affairs of role changing among piconets, the ability to dynamic constructing network is implemented in NS. And by modifying the role of BTHost modual, we let it provide the standard HCI interfaces. At the same time, by defining and implementing a set of standard protocols that communicate with BTHost, a flexible interface to control nodes is implemented.Last, under the extended Bluetooth simulation environment, the mechanism of Bluetooth device discovery is analyzed and simulated. By setting up a mathematical model for the probability of the discovered devices, the optimized value of the key parameter which improves the efficiency of the device discovery procedure is pointed out. The simulation further shows the great impact of the parameter on the efficiency of device discovery.