الفهرس 
chapter 1Only 14 pages are availabe for public view
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Abstract
Bluetooth is a promising new technology for short range, low power, low cost, low bandwidth, and wireless access connectivity between mobile devices. Any two or more Bluetooth-enabled devices that come within the range of each other can setup an ad hoc connection, called a piconet. Within the piconet, the device that establishes the piconet becomes the master and the rest of the devices act as slaves. The master organizes the traffic to share bandwidth among the slaves in the piconet using an intra-piconet scheduling scheme (polling algorithm). Efficient polling algorithms play a very important role in implement best performance under different situations.
The original polling algorithm in Bluetooth piconet is the Pure Round Robin (PRR) algorithm. In the recent years, several polling algorithms have been proposed to improve the performance of voice and data transmission traffic over Bluetooth piconet, and to enhance the back draws in the original Pure Round Robin (PRR) algorithm.
In this thesis, a new polling scheme for intra-piconet scheduling in Bluetooth piconets, Priority Gated Round Robin (PGRR) algorithm, is described, The proposed Priority Gated Round Robin (PGRR) scheme develops the existing GRR polling scheme in order to implement the priority among master-slave connections. It classifies the master-slave connections into three classes according to the presence or absence of data in each pair of corresponding master-slave queues. It takes into account downstream queue as well as upstream queue. The status of all slaves’ queues is re-examined after each cycle.
Bluetooth uses different Segmentation and Reassembly (SAR) schemes, which spread the packets used by higher layer protocols over several baseband packets to improve efficiency and reduce overheads. Two SAR schemes are used, the traditional SAR, and Best fit SAR schemes.
The performance of Priority Gated Round Robin (PGRR) algorithm is analyzed via simulation in different cases (different SAR algorithms, different packet sizes, and variable number of slaves) and is compared with the traditional Gated Round Robin (GRR) algorithm. Simulation results demonstrate that the PGRR scheme achieves high utilization of the piconet bandwidth in addition to low packet delay and wasted time especially at low load. Also, it provides high improvement in the performance over the traditional GRR algorithm.