Spanish researchers say a new sensor system can improve the ability of GPS to determine a vehicle's position by up to 90 percent.

The system of sensors to work with a vehicle's existing GPS can be installed in any vehicle at low cost, they said.

Researchers at Universidad Carlos III in Madrid said a commercial GPS in a car can locate the vehicle to within about 50 feet in an open field but in an urban setting it can be off by more than 160 feet due to the GPS satellite signals bouncing off obstacles like buildings, trees or narrow streets.

Their prototype system combines a conventional GPS signal with those of other sensors, including accelerometers and gyroscopes, to reduce the margin of error in establishing a location, a university release reported Tuesday.

Using the prototype the researchers have been able to determine the position of a vehicle to within 3 to 6 feet in urban settings.

"Future applications that will benefit from the technology that we are currently working on will include cooperative driving, automatic maneuvers for the safety of pedestrians, autonomous vehicles or cooperative collision warning systems," the researchers wrote in the journal SENSORS.

With further development, they said, it could be possible to incorporate the entire system within a smartphone, since many phones already include GPS, accelerometers and gyroscopes.

"We are now starting to work on the integration of this data fusion system into a mobile telephone," researcher Enrique Marti said, "so that it can integrate all of the measurements that come from its sensors in order to obtain the same result that we have now, but at an even much lower cost, since it is something that almost everyone can carry around in his pocket."