The software for this functionality has been resident in various certified SAASM receivers for some time, but was never implemented in the ground control segment.
Ground Control Stations
Several ground control stations exist for the GPS. The Master Control facility is located at Schriever Air Force Base (formerly Falcon AFB) in Colorado.
ground control - Physical points on the ground whose positions are known with respect to some horizontal coordinate system and/or vertical datum.
Ground Control: Point on the surface of the earth with known coordinates as represented by some geographic grid reference system.
7 Ground control points and OS maps
Of course, if the data are surveyed in from a GPS point, for example, and the co-ordinates are specified in full numeric form (e.g. 312300 445600 from the above example) the OS are not involved.
[edit] Ground control
The ground control segment of GLONASS is entirely located within former Soviet Union territory.
Ground control point(s); Geodetic control point(s)
GCRA
Geographic and Cartographic Research and Applications Section ...
The ground control points may be also (ir)regularly distributed and can be more than four points.
EXAMPLE
Most DXF/DWG drawings are done within XY coordinates. To transform them to a national grid, we can use 'v.
What is a Ground Control Point (GCP)?
Answer:
A precisely known UTM or Geographic coordinate of a point on the earth
used to geolocate the image. GCPs are needed to create absolute geolocated
DEMs.
Twenty three ground control points (GCPs) digitized from 7.5 minute USGS topographic quadrangles (USGS quads) were used to rectify the October 5, 1990 SPOT-XS image to a Universal Transverse Mercator (UTM) map projection (RMSE = 0.29 pixels / 5.91 m).
Effective photogrammetry makes use of ground control by which aerial photographs are carefully compared and registered to the locations and characteristics of features identified in ground-level surveys.
Identifiable points on the ground (ground control points) are used to determine distances and geometric properties of the image, including camera height above the ground, degree of tilt at the time the photo was taken, ...
One of the spin-off uses of these surveys is to set up specific ground control points that are needed to properly make measurements in aerial photos, especially, as we shall see, when these are to be used in making topographic maps.
Ground Control Point - GCP: Any point which is recognizable on both remotely sensed images, maps and aerial photographs and which can be accurately located on each of these.
Control - Also called ground control. A system of survey marks or objects called control points that have established positions and/or elevations verified by ground survey.
A system of transmitting satellites and ground control stations that allows someone with a suitable signal receiving and processing device (GPS receiver) to accurately determine their location at any point on or above the earth.
Acquire control points to produce about 35 orthoimages and determine the correspondence between the ground control points and satellite image to produce correction models for Landsat 7 images using the source material provided (or made available) by ...
During this phase of aerotriangulation, the coordinates of both the ground control points and the photogrammetric points are measured and recorded in the model coordinate system.
To determine elevation of a place, it must be surveyed, in reference to a ground control point.
Part of a topographic map of Haleakala (Hawaii), showing elevation.
[edit] Topography ...
This could be done through the reprocessing of raw image data with ground control points whose UTM coordinates were projected into the NAD83 framework.
raster image scanned from the diapositive or directly acquired from a digital sensor, 2) a digital elevation model with the same area of coverage as the digital orthophoto, 3) the image and ground coordinates of photo identifiable ground control ...
system to a known co-ordinate system on the basis of a set of selected points whose co-ordinates are known in both systems (given in the figure Overview of Coordinate Transformations as direct transformations). These points may be ground control ...
Supplemental control points are those needed to relate the aerial photographs used for mapping with the system of ground control.
 See also: Information, Image, Cover, Map, Control Point
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