Land surveyors once used tape measures and transits to measure distances and positions. Because 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. Enough time the beam takes to come back 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, using the location of several satellites to pinpoint an exact location. A receiver can determine the latitude, longitude, and elevation of a spot using four or even more satellites; there are always 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 is found in many devices, tracking from cell 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 these positions is probably the fundamental components of land surveying. The advantage of is that it is much more accurate than hand-measuring these locations. There is some degree 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 permits a lot more precise measurements than previously available 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 could be located precisely, while other methods of land surveying rely 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 over time, such as in case a house is torn down or another obstacle is built between the structure and the measured point; a good surveyor's stake may be removed before the land is re-surveyed. The coordinate of a given location on the planet, however, remains the same. Therefore, using GPS as a land surveyor produces measurements that'll be accurate regardless of what happens to the encompassing land.

Although Global Position System receivers allow for very precise measurements, there's still a degree of error involved. A receiver on a tripod will record the positioning slightly differently each and every time; when many measurements are taken, these data points will form a cluster round the actual location. Better- Measured Building Survey Ashton-under-Lyne , of course, reduce this quantity of error. Survey-grade receivers, rather than those designed for non-surveying uses, may create a group of measurements clustered in a matter of one centimeter of the actual location. Today's receivers are steadily gaining in use, but will not be as accurate because the surveyor want, especially in areas that are heavily wooded or which 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 working with GPS units has improved steadily.