I nterference is a fact of life in the unlicensed bands used by wireless LANs (WLANs), and is an increasing challenge in all WLAN environments – the enterprise, outdoors (including metro-scale Wi-Fi meshes), and in the residence. As the number of unli- censed devices grows and as ever more mission-critical applications are deployed on WLANs, interference represents a challenge that must be ad…