Land Surveying and GPS

Land surveyors once used tape measures and transits to measure distances and positions. Since the 1980s, electronic distance measurement, or EDM, devices have allowed for much more efficient and accurate measurements. These work with a wave of energy that is shot between the EDM instrument and a reflector. The time the beam takes to return is then calculated as distance. Today, such calculations can be done using sophisticated GPS systems.

The Global Positioning System uses a network of satellites to precisely pinpoint the device's location on the planet at any moment. GPS uses the principle of trilateration, utilizing the location of several satellites to pinpoint an exact location. A receiver can determine the latitude, longitude, and elevation of a point using four or even more satellites; there are a total of 24 Global Positioning System satellites currently used. First developed by the U.S. Department of Defense as a navigational aid in 1994, today it really is found in many devices, tracking from mobile phones and delivery vehicles to the movement of the tectonic plates of Earth's crust.

Land surveyors use Global Position Systems to notice the precise coordinates of spatial locations. Exact measurement of the positions is one of the fundamental components of land surveying. The advantage of is that it's a lot more accurate than hand-measuring these locations. There's some extent of error in every land surveying measurements, due to human errors, environmental characteristics like variations in magnetic fields, temperature, and gravity, and instrument errors. GPS allows for much more precise measurements than previously open to land surveyors using measuring tape and an angle sight.

Another benefit of the use of its use as a land surveyor is that the coordinates can be located precisely, while other ways of land surveying depend on measurements from other known locations, including the edge of the house line, the corner of a residence, or another landmark. These locations could change as time passes, such as in case a house is torn down or another obstacle is made between the structure and the measured point; a good surveyor's stake could be removed before the land is re-surveyed.  Click here for more  of confirmed location on Earth, however, remains the same. Therefore, using GPS as a land surveyor produces measurements that will be accurate no matter what happens to the encompassing land.

Although Global Position System receivers enable very precise measurements, there is still a qualification of error involved. A receiver on a tripod will record the location slightly differently each time; when many measurements are taken, these data points will form a cluster round the actual location. Better-quality receivers, of course, reduce this quantity of error. Survey-grade receivers, instead of those designed for non-surveying uses, may create a group of measurements clustered within just one centimeter of the specific location. Today's receivers are steadily gaining used, but might not be as accurate as the surveyor would like, especially in areas which are heavily wooded or that have other large obstructions. However, the technology is rapidly advancing and gaining a foothold in the available equipment for land surveyors. Since 1994, the accuracy available when using GPS units has improved steadily.