Wooden Nickel Positional Accuracy for a Dime?

Affordable Centimeter-Accurate GPS Developed

May 7, 2015 By Liz E.

GPS technologies are constantly improving and expanding. When first launched, GPS provided accuracy within several hundred feet. Then, when Selective Availability ended, accuracy skyrocketed literally overnight to a few meters. Now, a research team at the Cockrel School of Engineering at the University of Texas at Austin has found a way to increase that accuracy to a few centimeters without increasing the cost. The catch is that this new technology was funded by Samsung and therefore is designed specifically for smartphones.

This article focuses on single-frequency CDGNSS rather than multiple-frequency CDGNSS or other carrier-phase-based techniques, such as precise-point positioning (PPP), for three reasons. First, virtually all smartphones are equipped with single-frequency GNSS antennas tuned to the L1 band centered at 1575.42 MHz, and single-frequency CDGNSS will likely forever remain the cheapest option. Second, as compared to PPP, CDGNSS converges much faster to centimeter accuracy, which will be important for impatient smartphone users.Finally, as centimeter-accurate GNSS moves into the mass market, GNSS reference stations will proliferate so that the vast majority of users can expect to be within a few kilometers of one. In this so-called short baseline regime, the differential ionospheric delay between the reference and mobile receivers becomes insignificant, obviating differential delay estimation via multi-frequency measurements. Of course, the additional signal measurements produced by multiple-frequency receivers would lead to faster convergence times and improved robustness, but for many applications, single-frequency measurements will be adequate.

I know what you’re probably thinking. Centimeter-accurate devices are already available right now. IN fact, centimeter-accurate positioning devices are commonly used in several different fields including geology, mapping and surveying. However, these survey-grade antennas are a too large to use with a mobile device, and the antennas and equipment is pretty expensive. The researchers wanted to create a super accurate system that was affordable so that everyone could use it.

I’m not an expert on the hardware that goes into GPS and smartphones, so I’m not going to try and explain to you exactly how it works. But, basically what it sounds like is that the device uses the sensors already included in most smartphones alongside the existing GPS technology in order to decrease the range from an area the size of a car to the area the size of a nickel. You can check out the article in GPS World or the ARS Technica article to get a better idea of the technical side of it.

What’s of more interest to me is the ramifications of a technology like this. The research team listed off things that they believe the technology to be useful for—mostly gaming, because they are college students, as well as virtual reality. However, the first thing that comes to my mind is the use of drones and other similar things. I wouldn’t think that the FAA would be able to argue if you could land a drone within centimeters of a target without any difficulty. Self-driving cars suddenly don’t sound quite as scary—the possibilities are endless, especially if the technology can be replicated outside of the use of a smartphone (which I am sure is possible).

Right now, this is still in the research phase and is not commercially available, although theEureka Alert! article stated that the professor and his students have created a new startup called Radiosense and there are plans to build a clip-on accessory for smartphones to leverage this centimeter-accurate positioning technology.