EDM instruments can be classified based on type of carrier wave employed. The classification includes microwave, Infra-red, visible light instruments. It can be observed that all three categories of EDM instruments use short wavelengths and hence higher frequencies.

The use of compensator can be found in case of finding vertical angles, where instrument has to be perfectly levelled. But compensator isn?t sufficient to provide perfect levelling. Manual operation is also involved in obtaining perfect level.

The best procedure while using a Total Station is to set a convenient ?north? and carry this through survey by using back sight process when instrument is moved.

A sinusoidal wave describes oscillation periodically. Since electromagnetic wave is represented in form of sine curve it is named after it as sinusoidal wave.

Geodimeter is a classification of EDM based on carrier wave. This instrument uses visible light as its source and possesses a range of 25 km, having accuracy up to 2-3km.

Tellurometer is generally having a range of 100km i.e., it is capable of measuring distance up to 100km. In order to function properly it requires a high range propagating wave, which can reflect back to instrument.

Modulation involves overcoming of problems raised due to interference, scattering, etc. In this, measuring wave is super imposed on a carrier wave of high frequency, so it is also known as measuring wave.

Geodimeter uses visible light as a carrier wave in which it is capable of obtaining information, like distance between points, within 25km of range.

The range of lower frequency is not suitable in case of direct transmission through atmosphere because it may involve in atmospheric conditions like interference, reflection, fading and scattering. This may decrease impact of frequency which may reduce information being transmitted.

The data obtained from total station can be indirectly used in STAAD Pro, Autodesk Revit, Primavera but it can be directly used in software?s like Arc GIS, Surfer, Auto CAD etc., as y are linked with it.