Method of creating digital terrain models and its practical application as exemplified by Samara region

The article shows that high accuracy is one of the most important elements in the technology of creating such information products as a digital elevation model (DEM) of the terrain, so a reference is to be provided to confirm the accuracy. Unlike the methodological approach based on collecting data on the terrain relief using digitized topographic maps, a procedure is proposed to generate a reference DEM. The procedure provides high accuracy in solving the problem of coordinate referencing of control points due to differential processing of the navigation information obtained with the help of dual-frequency receivers of the geodetic class. In the course of work a technique for obtaining precise contour intervals of the terrain based on a rigidly bound algorithm for combining inertial and satellite measurements providing high-precision solutions even in the temporary absence of satellite signals was developed and experimentally validated. As a result of field and office works conducted in 2013-2015, a reference DEM with a size of about 50 × 50 km² was established that made it possible to evaluate the results obtained by DEM space stereo photography and make appropriate corrections in the program and methodical apparatus of  Earth remote sensing data processing.