Performance Analysis and Reliability Improvement of Bluetooth Broadcast Scheme

In bluetooth wireless system, data is transmitted between master and slaves by unicast or broadcast. With broadcasting, data can be transmitted to some or all nodes in a more efficient way in terms of consumed network capacity than sending the same packet to all nodes one at a time using unicast strategy. However, because the master transmits to all the slaves simultaneously, the acknowledgement mechanism does not work, and the reliable delivery of packet may not be guaranteed. In this paper, we study the performance of current bluetooth broadcasting scheme and obtain a result which can be used to determine the optimal packet type and retransmission count that can provide the highest effective throughput values for some practical BER ranges. To improve the reliability of broadcast, we propose a reliable packet delivery policy called extended-ARQ (automatic repeat request), which is an extension of ARQ in the one-to-multi communication system. Our simulation results show that the extended-ARQ policy guarantees the reliable packet delivery and maximizes the effective throughput by preventing a broadcast packet from being retransmitted unnecessarily