US Patent 9148935 Dual-technology occupancy detection

Apparatuses, methods and systems for dual-technology occupancy detection are disclosed. One dual-technology occupancy detection apparatus includes a motion sensor sensing motion, an ambient light sensor sensing variation in ambient light, and a controller for detecting occupancy and controlling a building environmental parameter based on the sensed motion and the sensed variations in ambient light. One method of detecting occupancy for controlling lighting includes sensing motion with a motion sensor, sensing variations in ambient light with an ambient light sensor, and detecting occupancy and controlling activation of a light based on the sensed motion and the sensed variations in ambient light.