Date Added: Feb 2009
As the number of wireless devices sharing the unlicensed 2.4 GHz ISM band increases, interference is becoming a problem of paramount importance. The authors experimentally investigate the effects of controlled 802.11b interference as well as realistic urban RF interference on packet delivery performance in IEEE 802.15.4 body area networks. The multi-channel measurements conducted with Tmote Sky sensor nodes, show that in the low-power regime external interference is typically the major cause for substantial packet loss. They report on the empirical correlation between 802.15.4 packet delivery performance and urban WLAN activity and explore 802.15.4 cross-channel quality correlation. Lastly, they examine trends in the noise floor as a potential trigger for channel hopping to detect and mitigate the effects of interference.