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GPS and Accessories
Frequently Asked Questions
  1. What is GPS?
  2. How does GPS work?
  3. What is portable GPS?
  4. Who uses portable GPS?
  5. What kinds of portable GPS devices are available?
  6. How accurate is GPS?
  7. What costs are associated with GPS?
  8. Does portable GPS require professional installation?
  9. What are some of the other benefits of GPS?
  10. How do I tell the GPS where I want to go?
  11. What is a traffic-information service?
  12. What else should I consider?
1. What is GPS?

Global Positioning System (GPS) is a satellite-based navigation system used for determining exact latitude, longitude and elevation measurements. Originally designed for the U.S. Department of Defense, GPS became available to the public in the 1980s.

Today, millions use GPS for worry-free travel. With preloaded maps, it's easy to plan trips, find alternate routes and locate points of interest. Bid bon voyage to the days of asking directions, taking wrong turns and printing out maps from the Internet.

2. How does GPS work?

GPS processes signals from four or more satellites every second. By calculating the time interval between the transmission and reception of these satellite signals, your GPS receiver is able to tell you exactly where you are — and more importantly when that next exit is coming up.

Three key elements work together with GPS:

  1. Satellites — GPS has 24 satellites that circle the Earth, ensuring that your receiver always gets signals from at least four of them to pinpoint your location.
  2. Monitoring stations — Five monitoring stations on Earth collect data from the satellites and send updated information back up to them, which increases the accuracy of GPS.
  3. A GPS receiver — Your receiver picks up all of the data that's sent by the satellites and updated by the monitoring stations to give you an exact location.
3. What is portable GPS?

Portable GPS uses the same technology as factory-installed GPS devices. However, you can move portable GPS devices from car to car and take them with you when you travel to other countries.

4. Who uses portable GPS?

People from all walks of life use GPS for a wide variety of activities. From finding the most direct route to your favorite vacation spot to navigating through congested city streets, GPS has become an indispensable tool for millions.

5. What kinds of portable GPS devices are available?

Here's a breakdown of the four types of GPS devices on the market:

Best for: Power source: Map feature: Special features:
Auto Driving navigation and finding points of interest. AC power source or car adapter. Detailed street-level maps. Multidestination planning, rerouting around construction and traffic areas.
Adventure Outdoor recreational activities. Battery powered (rechargeable). Varies — minimum of detailed base maps, including cities, interstates, lakes, rivers, national and state highways, railroads and coastlines. Pocket size.
PDA On-the-go city driving or walking. Battery powered (rechargeable). Detailed street-level maps. Incorporates integrated office and calendar software.
Marine Ocean and lake navigation and locating areas of interest (fishing spots). AC power source or battery powered. Detailed street-level maps, plus BlueChart® compatible for offshore cartography. Floats and is waterproof.
6. How accurate is GPS?

Over the last few years, GPS accuracy has improved by leaps and bounds. A standard GPS unit has a position accuracy of roughly 50 feet. Most GPS devices also sport a parallel multichannel design, which means they lock onto satellites as soon as they're turned on and stay locked on, even areas of dense foliage or tall buildings. Plug and play at its finest.

The development of WAAS (Wide Area Augmentation System) has taken GPS accuracy to another level. GPS receivers with WAAS capability have a position accuracy of about 10 feet. WAAS signals are compatible with all GPS receivers and no additional equipment or fees are required to use it.

7. What costs are associated with GPS?

There are no activation fees, monthly fees or service fees. The only cost is the price of your GPS device itself.

Keep in mind there may be fees for optional subscriptions, such as traffic information, satellite weather services and map upgrades.

8. Does portable GPS require professional installation?

No. Most GPS devices can be used right out of the box. Just turn on your GPS, and it will pinpoint your location and lock onto satellites by itself.

9. What are some of the other benefits of GPS?

GPS can inject more fun into any trip and take the stress out of travel. So, instead of worrying about what exit to take, you'll be figuring out what restaurant to try. You'll get from point A to point B and still see everything along the way. Find points of interest, tourist attractions, hotels, restaurants, gas stations, banks and ATMs.

Just running errands around town? Many GPS devices allow you to enter multiple destinations and will figure out the most efficient routes between them.

Stuck making a long daily commute? Most GPS devices offer a subscription to traffic-information services (available for a fee) — helping you detour accidents, construction and other delays.

Also, many marine GPS devices offer optional sonar functionality and subscription satellite weather service (both available for a fee).

10. How do I tell the GPS where I want to go?

Navigation systems offer easy-to-use touch screens to enter your destination. Save time by simply selecting your destination city, and then typing in a specific street address. Most GPS devices offer a "predicitive text" feature that gives suggestions for city and streets names after only a few letters.

Along with finding the most direct route to your destination, your GPS will also offer specific points of interest — like tourist attractions, restaurants, hotels and gas stations.

11. What is a traffic-information service?

Some systems offer the option of a subscription traffic-information service. This can be an invaluable tool for long trips and the daily commute. Traffic services can warn you of accidents, construction, sporting events and more along your programmed route. Your GPS will provide the best detour options to get around all the highway snags. At this time, only select metro areas have traffic-information services available.

12. What else should I consider?

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