Sure, GPS systems are reliable in wide open spaces, but in an urban settings, they go haywire. Tall buildings frequently interfere with the signal and direct drivers to the wrong block. Now a new type of antenna promises to enhance GPS precision in the city so you don’t end up on the road to nowhere.
Developed by the US Air Force Institute of Technology and the Locata Corporation, the VRay antenna eliminates multipath interference, the reason so many radio-based location systems go glitchy in cities. Multipath interference happens when satellite signals reflect off buildings and cause GPS units to get confused.
“Multipath is the dominant source of interference for GPS in cities and indoors,” consultant David Last, former president of the UK’s Royal Institute of Navigation, told New Scientist. “Nothing else causes as much serious error.”
The basketball-sized VRay uses a beam-forming antenna with 64 receiving elements that identify and subtract multipath and other interference to withdraw a clean signal. Locata’s CEO Nunzio Gambale says that, in one second, the antenna scans for millions of virtual beams, so it can distinguish what GPS signal is valid.
“The concept of beam-steering for GPS is well known,” said Last. “However, its use has been mainly confined to the military due to the high cost.”
Previous beam-forming antennae have included separate radio receivers for each element. They’ve also been too large for civilian and non-industrial markets. But the VRay contains only one high-speed receiver that switches between an array of elements.
Despite the lower cost and smaller design, VRay prototypes are still bulky. I mean, putting a basketball-sized anything on or in a car is going to be a bit cumbersome. But designers are working on streamlining the antenna so they’ll be flush with vehicle roofs and small enough to put on a soldiers helmet.
Until then, might I suggest one of my favorite relics of pre-GPS navigation: a trusty map, or road atlas. I promise, it won’t steer you into a ocean. I can’t say the same about GPS. Check out a video of the VRay’s interference-thwarting abilities here.