Bluetooth QoS Scheduler

Abstract: Bluetooth is a low cost, short-range radio technology that enables electronic devices to communicate wirelessly via ad-hoc networks. Different kinds of applications may run over these networks, some of these applications with particular Quality of Service (QoS) requirements. One such application could for instance be an Audio application which need data frames to be delivered at regular interval to work properly. The communication over Bluetooth links is totally controlled by one of the participating nodes. Since this node controls the traffic and thereby controls the QoS within the network its communicating behaviour is of great importance for maintaining QoS reservations. A central part in maintaining QoS reservations is the scheduler, which prioritises between different tasks to be done such as which device that is allowed to transmit next. There is no standardised way to implement the Bluetooth scheduler. However, a Bluetooth scheduler should be able to handle QoS reservations, maintain fairness among the participating nodes, and utilise the available bandwidth efficiently. Furthermore a key requirement in Bluetooth is simplicity, therefore a Bluetooth scheduling algorithm should be of low complexity. This master thesis presents a new patented solution for an intra-piconet scheduling algorithm that is capable of maintaining QoS reservation, while being fair and also meet the low complexity requirement. This algorithm is presented in detail in the thesis and has been implemented in an ns2- based Bluetooth simulator. Simulations in this simulator are presented that verifies the scheduling algorithms functionality.