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ABSTRACT: Global Positioning System (GPS) has become as an important tool in land use study. Using GPS, it is possible to conduct survey with less manpower and less time. In this study, land use analysis was carried out using handheld GPS and Total Station. Campus of Rajshahi University of Engineering & Technology (RUET) was selected as the study area for this study. Garmin GPS was used to locate ground position and track logs of different objects within the study area. Handheld GPS could receive and track satellite signals between 0 to 3 meters of positional accuracy. The aim of the study was to compare the land use survey results conducted by both GPS and Total Station. Primary input for mapping the whole study area was GPS readings which were collected during the field survey. GPS readings were processed using some software i.e. Map source, Google Earth, Google Sketch up, Auto CAD, Photoshop and developed land use map. This paper is an attempt to evaluate the performance of handheld GPS in land use survey. Precision of handheld GPS is low. Accordingly, the results of the GPS survey indicates about 12% errors compared with the results of Total Station survey. However, handheld GPS is recommendable to conduct preliminary survey and where there is scarcity of manpower and time.
KEYWORDS: Land use Survey, Handheld GPS, Total Station, Google Earth, Aut°CAD, RUET.
1 INTRODUCTION
The Global Positioning System (GPS) is an all-weather, space based navigation system. A GPS receiver can fix its latitude and longitude by calculating its distance from three or more Earth-orbiting satellites, whose positions in space and time are known. If four or more satellites are within the receiver's "horizon," the receiver can calculate its elevation, direction of travel and even its velocity. Errors inherent in the system dilute the repeatable horizontal accuracy of the computed position to a level of 20 to 100 meters. Actual position of an object is somewhere within a circle which has a radius measuring from 20 to 100 meters.
Conventional terrestrial survey method, such as Total Station, is used in land surveying with great efficiency, reduces field survey and permits to accelerate data acquisition with highest accuracy. Total Station (TS) combine an Electronic Distance Measurement (EDM), an electronic digital...