Sound based indoor and outdoor environment detection for seamless positioning handover

In this paper, we propose a sound-based indoor and outdoor environment detection method to realize seamless positioning handover for in-and-outdoor integrated positioning systems. The proposed method uses a special chirp sound probe which is propagated by a speaker of a mobile device and collected back through a microphone of the device. The indoor and outdoor environments are detected by analyzing the reverberation patterns of the retrieved probe. When we tested the proposed method at 46 indoor and outdoor locations, roughly 95% detection accuracy was achieved.