You probably have one, either through an app on your smart phone or tablet, or a specific device that you bought and keep in your glove box. You probably already know that these systems are satellite based and, if you use one, you probably wouldn’t want to drive without one ever again. Read on as we get into the nuts and bolts of GPS.
But, where did this GPS technology come from?
All started with the Sputnik, the first Russian satellite that was launched in 1957. Scientists found out that they could track the satellite’s orbit by listening to changes in radio frequency. In the 1960s, the US Navy developed the TRANSIT navigation system that relied on six satellites (later, ten) to keep track of submarines. Military personnel had to wait several hours, though, to gather information from these signals.
Meanwhile, the Defense Department saw the advantages of having constant navigation information and developed the NAVSTAR system in 1973. By 1978, the first satellite was launched and the system was completed in 1995. Of course, the military have since found countless additional uses for the GPS technology; for example, it is used today in guiding missiles and bombs.
The GPS navigation system uses twenty-four 2,000-pound satellites that send radio signals to Earth about:
• their locations
• precisely when a particular signal was sent
When a GPS receiver on the ground receives information from four or more satellites, it can provide information about its own location (plus its speed and elevation).
The history of GPS systems took a giant leap forward in 2000, when civilian use became practical.
That’s when the military stopped scrambling signals from satellites, previously done for security reasons. Industries such as commercial fishing or freight hauling could then begin relying on GPS technology. Meteorologists use these signals to measure wind speed, while geologists count on these systems to monitor earthquakes. GPS is now vital in multiple industries.
At the same time, more and more consumer products began using this technology as the size and price of GPS devices dropped.
Inevitably, GPS devices and systems found their way into cars.
Early on, companies scrambled to be the first to craft a system that was practical for cars, with Mitsubishi Electric and Pioneer proclaiming success in 1990. That same year, a device called PageLink appeared in a patent application; PageLink provided real-time maps for vehicular use.
In 1994, Oldsmobile offered a GPS system for people who purchased an Oldsmobile Eighty Eight. In 1995, more innovations took place, with Magellan offering a vehicle-based system and Oldsmobile unveiling GuideStar, which was also a GPS system for cars.
Then, in 2000, when the military ended its practice of fuzzing the satellite’s signals, GPS devices became much more available and affordable.
Watch this blog for our next installment on GPS: about the development of GPS technology in cars.