Wi-Fi-assisted Inertial Odometry (WIO) Measures Speed and Distance of Indoor Movement

Many devices, such as smartphones, incorporate inertial measurement units (IMUs) to calculate how far a device has moved; however, IMUs suffer from large drift errors, meaning that even minor inaccuracies can quickly become exaggerated. In outdoor environments, many devices use GPS to correct their IMUs but this does not work in indoor areas where GPS signals are unreliable or nonexistent.