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10 Factors to Consider When Selecting a GPS tracker

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This tutorial is about selecting a  personal tracking device  and getting started using it. Choosing a GPS receiver can be quite an overwhelming experience. If you look at handheld, portable GPS receivers that currently offer, you’ll have around 50–60 GPS receivers to choose from. That’s a lot of choices. And that’s only the beginning. After you purchase one, you still need to find out how to use it. This tutorial should take some of the confusion out of buying a GPS receiver and help you come up to speed using it. When it comes to selecting a GPS receiver, I won’t recommend that you buy a particular brand or model or tell you which is best for hiking, geocaching, or other activities. Rather, I follow more of a Socratic method, in which I ask you a number of questions that should help you make a pretty good and informed purchasing decision. Before you purchase a GPS receiver, you should spend some time kicking the proverbial tires. Don’t rush out and buy a receiver based ...

Real-Time Differential GPS may be approached in several ways

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While you can get more accurate fixes from such a system, it requires a number of additional, time-consuming steps, after data collection. Once you know the source of the differential corrections file, you have to get it, load it onto your computer, and execute software to produce the final corrected file. Wouldn’t it be nice if the  GPS tracker  simply gave accurate positions at the time you took the data? Further, there are some applications in which there simply isn’t time to postprocess GPS fixes–bringing a ship into a narrow harbor, for one example. Well, actually there is a way to provide instantaneous, accurate fixes: Real-Time Differential GPS. Getting Corrections for GPS Measurements – Right Now! Real-Time Differential GPS (RDGPS) may be approached in several ways: • The user can set up a base station over a known point and arrange for transmission of a radio signal from the base station to roving receivers. • The user’s  GPS Tracking Device ...

Some major component of GPS

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GPS might be divided up in the following way: The Earth The first major component of GPS is Earth itself: its mass and its surface, and the space immediately above. The mass of the Earth holds the satellites in orbit. From the point of view of physics, each satellite is trying to fly by the Earth at four kilometers per second. The Earth’s gravity pulls on the satellite vertically so it falls. The trajectory of its fall is a track that is parallel to the curve of the Earth’s surface. The surface of the Earth is studded with little “monuments”– carefully positioned metal or stone markers–whose coordinates are known quite accurately. These lie in the “numerical graticule” which we all agree forms the basis for geographic position. Measurements in the units of the graticule, and based on the positions of the monuments, allow us to determine the position of any object we choose on the surface of the Earth. Earth-Circling Satellites The United States GPS design calls for a t...

Why GPS is a primary source of data for GIS

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While this is a text on how to use GPS in GIS–and hence is primarily concerned with positional issues, it would not be complete without mentioning what may, for the average person, be the most important facet of GPS: providing Earth with a universal, exceedingly accurate time source. Allowing any person or piece of equipment to know the exact time has tremendous implications for things we depend on every day (like getting information across the Internet, like synchronizing the electric power grid and the telephone network). Further, human knowledge is enhanced by research projects that depend on knowing the exact time in different parts of the world. For example, it is now possible to track seismic waves created by earthquakes, from one side of the earth, through its center, to the other side, since the exact time may be known worldwide. GPS AND GIS The subject of this blog is the use of GPS as a method of collecting locational data for Geographic Information Systems (GIS). Th...

GPS gives people a method for both assigning and using absolute coordinates

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IN WHICH you are introduced to facts and concepts relating to the NAVSTAR Global Positioning System and have your first experience using a  electronic tracking devices   .  A sports club in Seattle decided to mount a hunting expedition. They employed a guide who came well recommended, and whose own views of his abilities were greater still. Unfortunately, after two days, the group was completely, totally lost. “You told me you were the best guide in the State of Washington,” fumed the person responsible for hiring the guide. “I am, Iam” claimed the man defensively. “But just now I think we’re in Canada.” Stories like the one above should be told now (if at all), before they cease to be plausible. Actually, even at present, given the right equipment and a map of the general area, you could be led blindfolded to any spot in the great out-of-doors and determine exactly where you were. This happy capability is due to some ingenious electronics and a dozen billion dollars...

Making Tracks with personal GPS tracking devices

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Remember the story of Hansel and Gretel, the kids who dropped breadcrumbs in the forest to try to find their way back home? Their story would’ve had a different ending if they had a GPS receiver because all newer GPS receivers leave electronic breadcrumbs (called tracks or trails depending on the manufacturer) while you travel. Every so often, the GPS receiver saves the coordinates of the current position to memory. This series of tracks is a track log or track history. (Because various GPS models handle tracks differently, check your user manual for specific details.) Note these differences between tracks and waypoints: Names and symbols : Although tracks and waypoints are both location data points, tracks don’t have names or symbols associated with them and can’t be edited in the GPS receiver.   Autocreation: Unlike waypoints  — that you need to manually enter — tracks are automatically created whenever a GPS receiver is turned on (that is, if you have the tr...

GPS tracker becomes more a part of our daily lives

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GPS is such an extremely important technology! It is no exaggeration to say that GPS is revolutionizing aspects of many fields, including surveying (slashing the costs of many kinds of survey efforts and bringing surveying to parts of the world where surveys are nonexistent, highly inaccurate, or long since outdated), the natural resource fields (providing rapid and far more accurate collection of field natural resource data of many kinds), and municipal planning (providing for the updating of all kinds of records based on accurate field checking), to name only a few.  electronic tracking device  is making practical the kinds of data collection which were simply out of the question only a few years ago because the necessary skilled teams of field personnel were unavailable and the costs of accurate field data collection were beyond the means of virtually all organizations which needed these kinds of data.  GPS is changing all that. Use of the kinds of methods taught ...