06 October 2009

BM#09 - Where Am I?

1983, a Korea Airlines Flight 007 was flying over the Sea of Japan. The weather was clear with some scattered clouds. Everything seemed normal, but the pilot didn’t realize that they flew over the prohibited Soviet airspace. Suddenly, two Soviet Sukhoi jet intercepted the aircraft. Two missiles were launched and struck the aircraft, causing it to spiral down and crash into the sea. All the passengers and crew aboard were killed.

The incident was caused by a navigational error and it could have been avoided by using a GPS. What is GPS? The Global Positioning System (GPS) is a satellite-based global navigation system using 24 satellites launched by U.S. Department of Defense. GPS was originally intended for military applications, but following the Korea Airline incidents, President Ronald Reagan ordered the U.S. military to make the GPS available for civilian use so that navigational errors like that could be averted in the future.

GPS provides reliable positioning, navigation, and timing services to worldwide users on a continuous basis in any weather conditions, any time of day or night, anywhere in the world, 24 hours a day. And what’s best: it’s free.

How does GPS work? GPS 24 satellites broadcast signals from space that are used by GPS receivers to provide three-dimensional coordinates (latitude, longitude, and altitude). For user, this lat-long information does not mean anything unless they use a map. The map is a road database where every square meter is encoded as geographic coordinates. Every time you move, your coordinates change. The GPS receiver will calculate your coordinates, find the exact coordinate in the map, and then display your location in the map. Hence, it is important to have an accurate map. Inaccuracy of the map will lead to navigational errors.

The map viewer can be in any forms. It can be a standalone GPS receiver with LCD display, a cellular phone with GPS capability, or, like what I am currently using, a GPS bluetooth combined with cellphone.

How can GPS be used in everyday life? The basic function of GPS is, of course, to find a destination. After we find a destination, we can ask GPS to create a route to it. The map automatically opens with the route to destination is marked with colored line. Audio instructions will be provided by the GPS to tell us the turn-by-turn direction.



Another basic service of the GPS is to provide information about nearby points of interest (POI). POI can be anything, from ATM machines, hospitals, gas stations, police stations, amusement park, restaurants, hotels, and many more.

More advance service from GPS provide not only precise driving directions, they can also receive and display information on
traffic congestion and suggest alternate routes. They can inform you the cheapest hotel available nearby, the cheapest gas stations, or they can even inform you a free space in parking lot. Unfortunately these services are still not available in Indonesia.

My fellow toastmasters, with the abundant capabilities of GPS, you don’t have to worry when traveling in an unknown
locations. All you have to do is hit the ‘Where Am I’ button, and the GPS will take care all the rest. And you can proudly say: “Follow me, I have GPS”

[Source: wikipedia, Garmin Mobile XT Owners Manual]

(c) created by MZ