Precision Comparing between Common Control Survey and GPS Control Survey

Control Survey is the basis of measurement; measurement work must follow the principle of control before detail survey. The precision of control points directly affects the accuracy of detail survey and construction measurement. According to the basic theory of measurement deviation and through actual observations, this paper compares and analyzes the precision of conventional control survey and GPS control survey. It turns out the accuracyies of the two survey methods are equivalent on plane control survey; while as for the elevation control survey, the precision of leveling survey is higher than that of GPS control survey. In view of that, this paper proposes to apply joint survey method combining GPS technology with conventional measurement technology on control survey, so as to obtain highly precise 3-D coordinates outcome of the control points.