The Use of GPSSIT (GPS Virtual Station Technique) With Total Station for the Measurement of Details in Residential Areas

Abstract

GPS become one of the most important tools used in several surveying missions during last one and half decade. It is confidently and intensively used in several surveying tasks from establishment of precise geodetic control networks to the measurement of features and details on land. To fulfill those tasks, there are several techniques that GPS suggests and are available to be used according to the required precision and the requirements of special applications. Under this concept, these GPS techniques can be stated as static, kinematic, semi-kinematic and on the other hand, with respect to the special precision requirements of different applications, they can also be stated as relative, absolute and DGPS techniques. Even if GPS ease the surveying processes for these applications when we use GPS, GPS can some times put forward some limitations. Therefore, it can be said here that GPS has still some difficulties and limitations especially when GPS signals are blocked by some obstacles such as buildings in urban areas. Therefore, one can experience with those cases frequently during the detail measurements in an urban area. Tall buildings, trees and etc in an urban environment can be the main constraints that can cause those GPS signal blockages. Here in this paper, it is argued if a technique is available and allows us to use GPS even for measuring those urban details without worrying about GPS signal blockages.GPSSIT is a technique that can provide this opportunity. So, any measurement process which uses GPS to collect details in an open land by utilizing GPS measurement method that does not need established control into the ground, can be carried out even in residential areas without worrying about the established ground controls.The paper introduces the technique and shows the test results with a standard deviation of ±4.84 cm obtained from the test carried out in the campus area of Selcuk University.