Tools for Evaluating Bluetooth Coexistence with Other 2.4GHz ISM Devices

Introduction Bluetooth (BT) technology is designed to operate in the 2.4 GHz unlicensed radio (UL) spectrum. Usage models for BT products indicate a strong likelihood BT will be collocated with a variety of different wireless devices operating within the same band. Understanding how these different wireless services coexist when they are collocated is a significant issue. It is important the " user experience " is positive when using wireless enabled products. As wireless applications move from ones of convenience to reliance, the capability to predict potential interoperability issues is imperative, in order to forestall negative consumer opinion. Corporation [1-7]. The research has focussed on developing a methodology for evaluating coexistence issues based on a stochastic model of the interoperability process, i.e., coexistence model. The coexistence model provides a prediction of the network performance for different scenarios based on statistical inference. Network performance issues such as packet error rate and transmission latency can be evaluated. As born out by our research and the work of others [8-13], BT coexistence is significantly impacted by the operational environment, i.e., hospital, factory floor, office space, or etc. The performance impact due to the variation in the BT operational location presents two viewpoints for coexistence evaluation: site-non specific and site specific. In general, BT product developers will be designing communication systems required to work in a variety of environments, i.e., site-non specific. The current coexistence model provides a set of analytical tools well suited for evaluating this issue. The model can assist in answering questions such as, " What type of environments will cause my BT application to degrade? " On the other hand, the end user is concerned whether or not the BT application will be impacted within their operational environment, i.e., site specific evaluation. Current work is focused on extending the tool set to include site specific analysis. In the next section an overview of the methodology used in developing the coexistence model is presented. This is followed by a brief overview of both BT and IEEE 802.11b. Based on the current state of the wireless networking market, the 802.11b is one of the dominate wireless local area networks (WLAN) and therefore a central concern for coexistence with BT wireless personal area networks (WPAN). The coexistence issues between BT and 802.11 b are then discussed, i.e., RF environment and the interfering network parameters. An example is then presented to illustrate the approach. This …