A study of frequency interference and indoor location sensing with 802.11b and Bluetooth technologies

Location-aware computing is regarded as a key feature of many future mobile applications. GPS serves well for most outdoor applications; however, its dependence on satellites makes it ineffective in indoor environments. Several technologies such as infrared sensing, radio frequency, ultrasonic and RFIDs have been proposed for indoor location sensing. Each of these methods has its own merits and shortcomings. Recently there has been an increase in the use of commodity wireless technologies like 802.11 or Bluetooth for indoor location positioning. Since BT and WLAN don´t get along very well, the paper presents experimental results of interference effect of one technology on the other. These results help in determining which of these two technologies is more suitable for location sensing applications. The paper also presents two techniques of how Bluetooth technology can be used (with and without the use of signal strength information) for location sensing. The paper concludes by suggesting some changes to the Bluetooth architecture to improve its capabilities for location positioning.