How Does a GPS Tracker Work?

February 22, 2012

A vehicle GPS tracker has gone from a luxury to a necessity for the frequent traveller. Learn how GPS trackers work.

GPS Tracker

A GPS tracker makes use of the Global Positioning System, or GPS, to establish the location of an object at any given time. A GPS tracker may be used to determine the physical location of a vehicle on land, a ship at sea, an aircraft or even a person, virtually anywhere in the world.

The Global Positioning System is a network of global navigation satellites operated and maintained by the US government since the early 1970s. This space-based system was set up to enhance the navigational systems existing back then. GPS can now provide accurate positional data at any given time, in any weather condition, anywhere on or near the Earth. This data may be freely obtained using a GPS receiver.

Each GPS satellite continuously sends out data that indicates its own precise orbital position, and the approximate orbital positions of the other satellites in the network. GPS satellite transmissions also include the overall system status and are time stamped for reference. To get an accurate GPS location, there has to be an unobstructed line of sight view between a GPS receiver and at least four of these satellites. Using the position and time information, the receiver performs a series of computations to pinpoint its own location.

In automotive applications, position data obtained via GPS may be superimposed onto a map to provide directions. A GPS tracker such as the Trackstick may be installed in a vehicle for monitoring. GPS trackers record positional data at regular intervals and this information can be stored in the device's internal memory or may be sent to a base station.

A GPS tracker can also be used to provide safety and security. For example, it can be utilized by law enforcement operatives to locate and recover a stolen car whose GPS alarm has been triggered at the time of theft.

Protecting Your Car with GPS Tracking

Protecting your vehicle from theft should be a multi-layered approach, and GPS tracking should be one of those layers. The first layer is making the vehicle less attractive to potential thieves by hiding any valuables and securing all means of entry. Parking the car in a safe place is part of that layer, too. Vehicle disabling devices like steering wheel locks, engine cut offs and similar technology is the next layer. An alarm system should be a layer of your defenses, too. A GPS tracking system is the final piece of the puzzle because it's not about keeping the car from being stolen, but getting it back if it is taken.

LoJack was the original tracking system for stolen vehicles. LoJack isn't really a GPS system, though. It uses a radio transmitter beacon. When activated, it sends out a signal that's picked up by police radios. Officers access a database to find the description and other pertinent information, and then triangulate and locate the vehicle. One advantage of the LoJack system is that it works basically anywhere. GPS systems require a line of sight to the sky; LoJack does not. That's because GPS systems rely on satellites to determine locations. LoJack works via standard radio transmission.

OnStar is the leading GPS tracking system in use in the United States. It comes equipped on many General Motors vehicles. By using a radio signal from a satellite as a gauge of distance, GPS calculates a vehicle's location via GPS link. OnStar not only can help locate your vehicle if it's stolen, but can dispatch help in the case of a breakdown or collision. There are options available like remote slowdown of the vehicle (to allow pursuing officers to apprehend the stolen vehicle) and a system to prevent the vehicle from being started. OnStar requires a subscription to the service.

RoadTrac is another GPS tracking system available for cars. It tends to be more "hands on" in that you can use your own web host and monitor the location of your vehicle. This can be handy when a teen or someone else is using your car. It offers some of the same features as the OnStar, in terms of a "panic" system in case of emergency, with a monthly service fee.

There are other GPS tracking systems available (many from security and spy technology stores that have popped up over the last few years), and there are sure to be more coming to the market all the time. Remember that tracking should only be one level of your security for your vehicle. You should also keep in mind there are advantages to the more established companies, because you aren't going to find you are without service one day because your tracking company is out of business.