Wednesday, August 31, 2011

GPS stands for Global Positioning System

Imagine your reach a new city in night in your car and are in search of a good food joint to have dinner and then to locate a hotel to stay. One way is you ask people and guided or misguided and may end up at a place you don’t like. Now again imagine that your car is equipped with a system that has a complete map of your country and tells you exact route to your destinations. 

Actually there is nothing to imagine, this is what is happening in the other world. I came across a live system a couple of months back about which I was listening/reading a lot for few years. I am talking about GPS (Global Positioning System), a technology which is emerging fast and will not be surprising that it comes to India very soon. I will discuss the practical scenario of this technology first and then will brief about the technology itself. 

Although this technology is being used in many areas (not in India as of now), I will share my experience I had while traveling by taxi on many occasions in Europe. I hired a Taxi from Den Haag Central Railway Station for my hotel. The cab driver asked me about the name of the hotel. 

He switched on his GPS instrument which had a monitor to display maps, a mini keyboard/switchboard and speakers. When you go to buy a car now-a-days in developed countries, you are asked whether you want the car equipped with GPS system. So the driver had various options on his display screen – Hotels, Restaurants, Roads, Cities, Museums etc. etc. Driver clicked on hotels and got a list of alphabets, he then clicked on the first alphabet of my hotel. Now he gets a list of all the hotels of that city starting with that alphabet. He goes page down and selects the name I told him. And the wonder starts. The road map appears on your screen as good as you are carrying an elaborative map in your hands. You put on the speakers and a voice (male or female – depends on what you select) starts guiding you. To start with it will tell you that you have selected this Hotel (the hotel name) as your destination. It tells you that it will be this much distance from here. 

Now start the vehicle and go straight for 500 meters, then take a left turn, now keep right as you have to take a turn after 300 meters and so on. And in next 25 minutes I was at my hotel. No need to remember the roads, route et al. Second instance I will mention about my friend who was coming by his car from Belgium to meet me and then we had to go out for dinner. There are two routes from Belgium to Den Haag, but without bothering which route should be taken, he just fed my hotel’s name in Den Haag and the car started telling him the exact route through map on his display screen and through voice. We decided to go to a good restaurant around 15 kms away from my hotel. Just fed in the system what type of restaurant we wanted to go and it gave us a list of those type of restaurants. We selected one and it gave us the exact route and started telling where to go straight, where to take turns and at destination announced that we have reached our desired destination. While coming back we just had to tell the system that we have to reach from where we started. 

And we got the exact route. No botherations to take care of road names, street names, places, not to ask anybody. What a great companion. Now About GPS GPS stands for the Global Positioning System. It refers to a system of satellites and receivers that allow people and devices to pinpoint their precise location on the earth. The heart of the system relies on 24 satellites that orbit the earth twice per day. Devices that are equipped with GPS equipment receive transmissions from at least a few of the satellites and are able to discern very precise positioning data. The first GPS satellite was launched in 1974 and the 24th was launched in 1994. The system is operated by the United States Department of Defense and use of the system is free for anyone. New satellites are periodically launched to replace aging ones. As the technology has improved, the cost of GPS devices has plummeted while the accuracy has increased. Small portable GPS receivers have become very affordable, and the accuracy is amazing. Accuracy varies based on various factors, but it can be as good as a few meters! Land-based supplemental devices can be used to improve accuracy if higher precision is required. 

The application of the GPS is very broad, and as the prices come down the number of uses is increasing. Portable GPS devices are used by fisherman and hikers to help them navigate in the wild. Many new cars are being equipped with GPS systems to help drivers with navigation. The military uses GPS to guide cruise missiles to pre-specified targets. On 2 May 2000, the Department of US Defense switched off selective availability (SA) which made GPS readings less accurate. They reserve the right to turn it back on during national crises and the like, but for the most part GPS devices are now about 10 times more accurate than they were when selective availability was turned on!

No comments: