Performance Analysis of Periodic Busy Tones Protecting a ZigBee Network from Wi-Fi Interruption

Generating a busy tone is known as a good solution that enables a ZigBee network to coexist with any Wi-Fi network in the same ISM band. To generate a busy tone, ZigBee networks need to deploy a signaler that transmits it with the same power as Wi-Fi nodes, thus preventing other Wi-Fi nodes from accessing the corresponding channel. In this paper, we mathematically analyze the delivery ratio and delay of such a ZigBee network using a Markov chain model when busy tones are periodically generated. Based on the analysis, we derive a simple scheduling algorithm that adjusts the period of the busy tone. The analytic results are verified through simulation results which confirm that periodic busy tones enhance the performance of ZigBee transmissions.