WiCapture

Immersive experiences like virtual reality require accurate tracking of the headset and other accessories like hand-motion controllers. WiCapture is a system that achieves sub-centimeter-level accuracy of virtual reality accessories using commodity WiFi devices. WiCapture does not require special hardware, it uses commodity APs that can be bought in retail stores. WiCapture is occlusion resistant, it continues to work even when the APs and headsets are occluded due to furniture or other objects in between. WiCapture has larger range and operates across rooms. It is insensitive to room illumination or texture and it can work in the dark. Further, headset complexity is minimal, all the headset needs is a standard WiFi chip.

Demo Video

Paper

Position Tracking for Virtual Reality Using Commodity WiFi
By Manikanta Kotaru, Sachin Katti.
CVPR, 2017.
[ PAPER ]

WiCapture advances the state-of-the-art WiFi based positioning accuracy by two orders of magnitude by reducing the positioning error from few decimeters to few millimeters. To achieve such accurate tracking, one needs to measure time of flight between the WiFi signal source and the WiFi receiver with accuracy of few pico-seconds. However, there is much larger time-offset between the clocks used by the signal source and the receiver, and this offset varies over time. At the heart of the paper is a cute idea about how we can remove this time-offset by using signal from multiple paths. This result is surprising as multipath is generally considered as a challenge in the localization systems whereas it acts to our advantage here.

Code and Data

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Data