Researchers demonstrate centimeter-level positioning using smartwatches

University of Otago – Ōtākou Whakaihu Waka researchers have developed algorithms that improve the precision of location tracking in smartwatches.

Led by Associate Professor Robert Odolinski, a visiting researcher with Google from Otago’s School of Surveying, the research team demonstrated that a smartwatch determined its location with centimeter-level precision over four hours with a stationary setup. The result was achieved by using the Google GnssLogger app and combining precise signals from several GNSSs.

The research was done in collaboration with Google’s Android Context group and the Chinese Academy of Sciences. Results are published in the scientific journal GPS Solutions.

For decades, achieving centimeter-level positioning has required industries such as surveying, construction and engineering to invest in expensive GPS equipment.

“While the use of the so-called carrier-phase signals has long been known to improve the positioning performance, the specialized antenna and receivers needed for this have traditionally come at a cost far beyond the reach of many who would benefit from the technology. This is just the beginning of what wearable high-precision positioning can potentially achieve.”

GPS was introduced in a wearable watch in 1999, but hardware and power consumption limitations prevented it from tracking the carrier-phase signals needed for high-precision results. Recent advances in smartwatches now make this possible.

Precise centimeter-level positioning on a smartwatch during 4 hours of data in Dunedin, New Zealand. The dots show the repeatability of one second of data in comparison to precise benchmark coordinates. The repeatability of the positioning is about 8 cm, at most twice as large as the smartwatch diameter of 4 cm (displayed to scale).