Analysis and modelling of interference in bluetooth device discovery

During Bluetooth device discovery process, nodes enter inquiry substate to discover other nodes within the range by periodically sending inquiry packets on a predetermined frequency partition of hop frequencies used by neighbouring piconets. Intuitively, potential collisions will occur between inquiry packets and packets exchanged between piconet nodes during connection state, which lead to degraded network performance and longer discovery process. So, the authors developed an analytical model for interference caused by a single inquiring node, and extended the model to account for interference levels due to multiple inquirers. The authors further validated the analytical model through a simulation scenario and found that the probability of packets interfered and disrupted during inquiry procedure is periodic by repeating every 3.16 s. Analytical and simulation results reveal that a single inquiring node can disrupt up to 1.5% of network packets for approximately half of this period, and with the increased number of inquiring nodes, the interference levels become more crucial approaching 35.3%.