Another great leap for GPS?
- By Derek Major
- Feb 17, 2016
When the U.S. government turned off the selective availability of Global Positioning System satellite signals in 2000, it sparked something of a geospatial revolution, enabling the accuracy of GPS location data to improve tenfold -- from roughly 100 meters to 10.
Now a group of researchers have developed a new method to process GPS data more precisely still, strengthening the location accuracy to a few centimeters. That improved technology could be hugely important for autonomous vehicles, as well as for aviation and naval navigation systems, mobile phones and wearable technologies.
Today’s standard GPS systems can place a vehicle, person or anything with a GPS receiver on it to within approximately 10 meters of its actual position. Differential GPS has enhanced the system through a network of ground-based reference stations, but even the improved accuracy -- which can be as precise as one meter -- is not enough to support driverless cars, precision farming and navigation applications in the future.
Jay Farrell, professor and chair of electrical and computer engineering at the University of California, Riverside’s Bourns College of Engineering, explained that his team's approach combines GPS measurements with a device's own inertial measurement unit. The GPS provides accuracy, while the IMU provides continuous updates without bandwidth restrictions.
“To fulfill both the automation and safety needs of driverless cars," Farrell said, "some applications need to know not only which lane a car is in, but also where it is in that lane -- and need to know it continuously at high rates and high bandwidth for the duration of the trip.”
The two datasets, along with a new data-processing approach that requires "several orders of magnitude fewer computations," make real-time, centimeter-level accuracy possible, Farrell said, even on low-power processors like those used in smartphones and other mobile devices.
Derek Major is a former reporter for GCN.