Adaptive role switching protocol for improving scatternet performance in Bluetooth radio networks

Bluetooth has been considered as a high potential technology for providing wireless communication in a home-networking environment. In a Bluetooth network, it is difficult to control or predefine a scatternet structure because that the scatternet is formed using a distributed procedure, with the master and slave connected at random. A badly structured scatternet exhibits the following characteristics. Firstly, too many bridges in the scatternet will create a guard slot overhead associated with bridge switching among the participated piconets, increasing the probability of packet loss. Secondly, too many piconets in a communicative range will cause packet collision and thus degrade the performance. Unnecessary piconets also lengthen the routing path and transmission delay. This work proposes a distributed scatternet reconstruction protocol for dynamically reorganizing the scatternet topology. By applying the role switching operation, the unnecessary bridges and the piconet can be dynamically removed and hence, improve the packet error rate, save guard slots, and reduce the average routing length. Experimental results reveal that the proposed protocol significantly improves the performance of a Bluetooth scatternet