Before GPS accuracy was in meters, but soon that precision will be centimeters. A few months ago a landslide occurred in Leijiashan, in China’s Hunan province. Twelve days before, its leaders received a warning message: the Chinese geopositioning system, BeiDou, warned that it had detected signs of a possible incident of this type.
That notice allowed the damage to be only material: the lives of all its inhabitants were saved thanks to a system that is capable of differentiating a change in the terrain the size of the tip of a pencil at 21,000 km altitude. The implications of that precision are remarkable.
GPS is fine, Galileo and BeiDou are even better
They had it recently in Technology Review, where they talked about the fact that there are already several Chinese towns that have monitoring systems for natural disasters of this type.
They had it recently in Technology Review, where they talked about the fact that there are already several Chinese towns that have monitoring systems for natural disasters of this type.
Global geopositioning systems such as BeiDou, GPS or Galileo are receiving a series of critical improvements and updates to improve precision, which was previously counted by meters and is gradually being measured in centimeters.
This improvement in precision will allow to carry out tasks that until now were much more complicated, and for example will simplify the deployment of autonomous cars, which will have a much more precise notion of where they are (including the lane within a road) to act on that accurate data.
The GPS system that began operating in 1993 —the 24 satellites that make it up began to be launched 15 years earlier— have an accuracy of between five and ten meters, but this network is in the process of being updated: the GPS III system will take some time It will be fully operational for some time – four of the 10 satellites that will comprise it have been launched, the rest will finish being put into orbit in 2023 – but that precision will be reduced to 3 meters.
BeiDou is even more precise: its 44 satellites operate in three different orbits and offer positioning services with an accuracy that ranges from one and a half meters to two meters overall. In specific areas of Asia such as China, however, users can get as close to an accuracy of one meter.
The same is the case with Galileo, the geopositioning system created by the European Union and which is already providing service – although it does not hold too much for the moment – through 22 of its 26 satellites. The accuracy is better than that of GPS, reaching less than one meter in some cases, and even in the case of high-precision service with encrypted signals the position detection can be as accurate as 20 cm.
Towards millimeter GPS accuracy and quantum positioning
These systems use various techniques to further improve precision and bring it to centimeter levels. Options like Real-Time Kinematik (RTK) and Precise Point Positioning (PPP) are helping, and in China they are even beginning to combine them to make accuracy even better for years to come.
There is already talk about how these systems will be able to approach millimeter precision in the future, but that seems to be the limit . Experts want to go further and avoid dependence on satellites and there would come into play alternatives for interiors like this one or, even more important, the quantum properties of matter that allow them to be located and guided without the need for external references.
This quantum positioning can be very useful if we do not have information from GPS systems (as it happens in space or underwater), but it can also be an auxiliary system for autonomous cars in case the GPS / BeiDou / Galileo systems do not work correctly.
In fact, one of these systems in a very preliminary phase is already working on the International Space Station. The advances are therefore remarkable, and as we have seen their practical implications can be truly remarkable.
Also Read | Google improving Android GPS accuracy dramatically to major cities of the world