Whether you’re running a fleet of trucks or need to know where your kids are, GPS tracking is one of the safest technologies on the market. GPS can also help your business save time and money by delivering goods to customers more quickly.
A GPS is a radio-navigation system that provides positioning, navigation, and timing services via satellites. Your GPS device has a receiver that constantly seeks signals from satellites and calculates your distance from each one.
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What is a GPS?
A GPS, or Global Positioning System, is a network of satellites and receivers that can track your location anywhere on Earth. It was initially developed for the military but is now used by hikers, cars, airplanes, and space shuttles. It can provide highly accurate data, down to within one centimeter.
The navigation satellites are situated in orbit around the Earth, sending out radio signals that are received by devices such as those in your smartphone or car. These receivers are continually searching for signals from at least four satellites in their line of sight, measuring the distances to them. By evaluating these distances, the devices can ascertain your geographical location, pinpointing your coordinates in latitude and longitude.
Some GPS receivers include atomic clocks to improve accuracy. A 0.001-second error equates to about 300km inaccuracy, so keeping your GPS clocks synchronized with the satellites’ is essential. Other technologies that help mitigate errors include subscriptions to GNSS/GPS correction services, SBAS (wide area augmentation service), and the fusion of additional sensors like inertial navigation systems or radar.
A-GPS, or Assisted GPS, uses cellular networks to augment the quality and precision of GPS signals. This is especially helpful in geographic locations that obstruct the line of sight to satellites – whether natural ones like forests or mountains or artificial ones like skyscrapers overhead bridges.
How does a GPS work?
A GPS unit has an antenna that picks up the radio waves transmitted by satellites. It also has a processor that decodes the signals and computes your position on Earth using trilateration. The most basic GPS devices, like those in smartphones and car navigation systems, use three satellites to determine your 2D position (latitude and longitude). Most GPS receivers can track eight or more satellites simultaneously to provide more precise information about your location on Earth. For example, Garmin GPS technology is famous for organizing and displaying GPS data.
How do I choose a GPS?
A satellite’s signal includes information about the time it was sent, plus a code that gives your GPS receiver your exact location. It also knows how long it took for the signal to reach your device from the satellite, and it has an electronic almanac that tells it how far away each one is from your device.
A GPS satellite has an atomic clock that provides highly accurate time data and sends that info along with the satellite’s signals to your GPS receiver. The receiver uses this time data to synchronize with the satellites’ clocks and then computes the distance between you and each of the satellites using trilateration. Suppose the atomic clocks in the satellites are synchronized with your device’s GPS chipset. In that case, it can avoid the need for an atomic clock inside your receiver (though some GPS units have this feature and can pull precise atomic time from a network of RTK base stations). As you go, more distance measurements are made to help precisely compute your position.
What are the benefits of a GPS?
One of the primary advantages of this navigation technology is the revolution it brings to map usage. Rather than referring to confusing paper maps with intricate legends and directions, this system shows your exact location and offers highly precise navigation guidance.
Another boon is the capability to assist in bypassing traffic congestion. Being caught in traffic can waste precious time and potentially cause delays in reaching your destination for important appointments. Tools such as traffic reports and route planners within this technology facilitate maintaining punctuality by revealing the fastest paths.
Utilizing tracking in vehicles may also reduce fuel expenses for businesses by identifying behaviors leading to higher fuel consumption, like inefficient routes or fuel overuse. In the transportation sector, this can translate into notable financial savings.
Handheld navigation units prove invaluable for adventurous explorers, particularly those venturing into wilderness areas lacking cellular coverage. These devices usually feature robust, weather-resistant construction, offering dependable guidance in isolated regions. They can also synchronize with specialized software to manage and visualize recorded trails and waypoints.
Devices utilizing this navigation technology are tailored for cars, motorbikes, and individual use, such as walking, running, or cycling. Selecting the appropriate one depends on your intended use and the specific functionalities you need.
Some of the essential functions to consider include:
The ability to record tracks or waypoints. This is useful for recording your route and finding the best path back to your starting point or evaluating a trail you’ve done in the past. The ability to display the track on a base or topo map. Some units also allow you to download maps and routes to share with other users via a computer or the internet.
Screen type: Look for a bright, clear screen. The best ones feature a transflective type, reflecting sunlight and working well outdoors. Consider the screen size, too: larger screens are easier to read and can work better with gloves.
Battery type: AA batteries are still the standard, but many manufacturers are moving to rechargeables. This reduces waste and allows for more precise tracking and battery life.
Accuracy: Consider the number of satellites a device can see, as this will impact its accuracy. A GNSS-only GPS can only pick up about 12 satellite signals (GPS = green; GLONASS = blue). A dual-band GNSS unit, like the Garmin DriveSmart 55, can see up to 17 satellites for a more accurate position.