Mutual interference between independent bluetooth piconets

Abstract

The Bluetooth wireless communication technology provides wireless solutions applicable for a number of communications needs. In addition, multiple independent piconets are possible and likely to occur within the same location, either intentionally or by chance. Bluetooth devices utilize frequency hopping and independent piconets operate on different hopping sequences. Although the use of independently selected hopping sequences reduces the likelihood of mutual interference, as the number of colocated piconets increases, mutual interference becomes more likely. Mutual interference is also dependent on the performance requirements dictated by the application utilizing Bluetooth technology as well as the environment in which the piconet is operating. A method for analytically evaluating mutual interference for Bluetooth technology is presented. Models were developed for a single Bluetooth interferer as well as multiple interfering Bluetooth piconets operating in an arbitrary environment. The analytical models are based on two sets of parameters: Bluetooth interference and radio propagation. Empirical tests have been conducted to both support the derivation of the analytical models as well as to substantiate the analytical model results. The analytical results fall within the 95% confidence bounds of the empirical test results. Mutual interference analysis is presented based on evaluating the analytical model over a wide range of the multidimensional parameter space. The analytical model presented is a general approach well suited for evaluating mutual interference for applications using Bluetooth for data communications.