In this project we are designing a platform for low-power real-time sensing of the shape and number of occupants in indoor spaces. The system transmits a wide-band ultrasonic signal into a room and then processes the superposition of the reflections recorded by a microphone. The system has two modes of operation, one for presence detection and one for estimating the number of occupants in a region. The presence detection uses the difference between multiple transmissions in succession with a set of general classifiers that make a binary decision about if the room contains occupants.
