Ultrasonic Arrays for Localized Presence Sensing

Advanced sensing solutions are central in the realization of energy-efficient lighting systems. This paper presents an ultrasonic array sensor for localized presence sensing in indoor environments. Localized presence sensing refers to the determination of presence and locations of occupants. Our proposed sensing solution comprises of a single transmitter and a linear array of receiving elements. In order to meet presence sensing requirements in indoor office scenarios, a pulsed sinusoid transmitter waveform and receiver processing algorithms for location estimation are designed. The signals at the receiver array are processed to obtain range and direction-of-arrival estimates. These location estimates are improved using a tracking algorithm based on occupant movement models and by mitigating multipath effects. The performance of the proposed presence sensing solution is shown in multi-occupant office environments.