Apparatus, method, and software systems for smartphone-based fine-grained indoor localization

Abstract

Techniques for accurate, low-complexity, scalable indoor localization. Low-complexity anchor nodes generate acoustic beacon signals, which are passively detectable by a mobile device, which may be unmodified smartphones operating in an acoustic frequency range. The acoustic beacon signals are modulated via codes in a boundary band of audio and ultrasound frequencies, imperceptible to humans yet detectable via a voice microphone of an unmodified smartphone. An application on the mobile device passively captures the acoustic beacon signals and determines relative distances to the anchor nodes. Localization and distance update techniques, implemented on the mobile device and/or a remote server, determines and updates in real-time the location of the mobile device. The system may be scalable to support any number of mobile devices. Based on the tracked location, the indoor localization system may provide indoor location-based-services (LBS) to the mobile devices, and transmit to the mobile device information relevant to its location.