US Patent 10499364 Identifying static leaf nodes in a motion detection system

In a general aspect, a motion detection system manages leaf nodes used for sounding by one or more access points. For example, an access point obtains presence information for a plurality of AP-leaf node links for a plurality of calibration periods. Presence activity is determined for each AP-leaf node link in each calibration period based on its respective presence information. Static leaf nodes are identified based on the presence activity for the plurality of AP-leaf node links in a calibration window, the calibration window comprising a number of the plurality of calibration periods. The motion detection system is updated to use at least one of the identified static leaf node as a sounding node for motion detection.