This year, the Global Positioning System marks its 30th anniversary of being freely accessible to the public. It has become a near-ubiquitous tool for a variety of military and civilian uses. But we’ve only just begun to scratch the surface.
The U.S. Air Force, the custodians of the GPS satellite constellation, are already preparing for the initial rollout of the third-generation satellites in 2014. Known as Block IIIA, the newer equipment boasts a variety of upgrades like more transmission power and greater accuracy thanks to additional civilian-accessible signals. That means accuracy to within 3 feet (today’s upper limit is 10 without augmentation) and better accessibility in reception-poor areas like concrete jungles and under tree cover. It's both powerful civilian signal tech and enhanced GPS that's changing how we think about global positioning. Let's take a look.
Even a more accurate GPS signal has its limitations, and the most interesting applications pair GPS with other sensor technology. Self-driving cars, for instance, have made great strides in the past few years. Laser rangefinders and radar help the driving computer understand where the vehicle is in relation to other objects, like cars and road hazards. Cameras sense when lights are red and detect the edges of the lanes to keep the car on track. In response, the system can hit the brakes, swerve to avoid an obstacle, or speed up to keep up with traffic. Many of these systems are already available as driver assistance on high-end cars, automatically gliding into tight parallel parking spots or cinching up safety belts and braking hard when a crash is imminent. But don’t be surprised when driving becomes a mostly hands-off experience in the next few decades.
For urban dwellers, the next step to cover is indoor navigation. That means typing in a home or office address and your smartphone guiding you to the building, up to the appropriate floor, and to the door of wherever you want to be. GPS works nearly perfectly when out in the open, but buildings and tree cover interfere with the signal.
Currently, indoor navigation relies on a variety of hacks using other sensors built into the smartphones we usually have in our pockets. Signals from ordinary Wi-Fi routers with known locations can be used to triangulate a receiver, just like a traditional GPS unit uses satellites. Some companies like Locata are experimenting with extensive (and expensive) tracking beacons that can penetrate walls and provide accurate locations inside buildings, or light fixtures that beam unique patterns to a smartphone’s camera – sort of an automatic QR code. Other potential solutions use the phone’s accelerometer to count footsteps from a known location, or even using the compass to pick up on the minute fluctuations in a building’s magnetic fields.
In other words, we’re getting there, if little by little. But in the future, GPS will be able to connect to more robust iterations of this technology to give us a view of location data behind building walls.
Indoors or out, more precise pinpointing has plenty of implications for augmented reality, and we're already seeing the results. Tourists can point a phone’s camera at the Brooklyn Bridge and pull up its Wikipedia page, and hungry diners can see star ratings superimposed on the restaurants when looking down the block. Drivers are even treated to turn-by-turn directions with a full 3-D map — right in their windshield. GPS units in London’s buses keep track of their location, and commuters can use an augmented reality application to find out when they’re due to arrive, as well as the closest stop to hop on.
Finally, for those more socially minded, the next generation of GPS has some humanitarian applications as well. Future Block III satellites will include hardware for the Distress Alerting Satellite System, a joint project by NASA, the Air Force, NOAA, and other agencies to improve search-and-rescue operations. The improved satellites will be able to detect the signal sent out by distress beacons — usually found on ships and devices carried by backcountry hikers — and relay the location back to response teams nearly instantaneously. It improves on the current system, which relies on weather satellites that require the beacon to transmit its location, or low-earth-orbit satellites that may be out of position when the distress call is made.
The Air Force is ready to launch its next GPS satellite — and they want you to help. They've launched The Air Force Collaboratory to allow anyone interested in the science and tech behind GPS and more to share ideas of where the future will take us. The placement of satellites is crucial to the performance of the system and all its applications, and they’re asking the world to help make the best decision possible.
This is your chance. Want to learn more about the next great satellite system? Head on over to The Air Force Collaboratory to help them select the coordinates for its new home.