rtk: Real time kinematic (RTK) check points for data accuracy
Hubbard, T.D., Koehler, R.D., and Combellick, R.A., 2011, High-resolution lidar data for Alaska infrastructure corridors: Raw Data File RDF 2011-3, State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys, Fairbanks, AK USA.
This is a point data set.
The map projection used is Alaska Albers Equal Area Conic.
Planar coordinates are encoded using coordinate pair
Abscissae (x-coordinates) are specified to the nearest 0.000001
Ordinates (y-coordinates) are specified to the nearest 0.000001
Planar coordinates are specified in meters
The horizontal datum used is North American Datum of 1983.
The ellipsoid used is Geodetic Reference System 80.
The semi-major axis of the ellipsoid used is 6378137.
The flattening of the ellipsoid used is 1/298.257222.
|Range of values|
Data collection was supported by funding from the Department of Natural Resources (DNR), Division of Geological & Geophysical Surveys (DGGS), the Alaska Gas Pipeline Project Office, the Office of the Federal Coordinator, and the Alaska Gasline Development Corporation (AGDC). Lidar data were collected and processed by Watershed Sciences, Inc. of Corvallis, OR. Survey data were collected by McClintock Land Associates of Eagle River, AK. Lidar data and derivative products were checked for quality, completeness, and accuracy by State of Oregon Department of Geology & Mineral Industries based in Portland, OR.
Provide real time kinematic (RTK) check points for data accuracy.
RTK data were collected during periods when Point Dilution of Precision (PDOP) was less than or equal to 3, and with at least 6 satellites in view of both a stationary reference receiver and the roving receiver. The surveyor begins collecting data after remaining stationary for 5 seconds, then calculating the pseudo range position from at least 3 epochs with the relative error under 1.5 cm horizontal and 2 cm vertical. RTK measurements were not taken on highly reflective surfaces and were taken no closer than one meter to any nearby terrain breaks. Static GPS data from the reference receiver were processed using triangulation with Continuously Operating Reference Stations (CORS). Please refer to the lidar delivery report for details about the survey accuracy for individual datasets.
The RTK data is accurate to 1.5 cm or less.
The RTK data is accurate to 2 cm or less.
RTK data have been checked for accuracy and completeness. Please refer to the lidar delivery report and lidar QC report for details about data completeness for individual delivery sets.
RTK GPS surveying involves using a GPS base station deployed over a known monument with a radio connection to a GPS rover. Both the base station and rover receive differential GPS data and a baseline correction is resolved between the two.
Are there legal restrictions on access or use of the data?
- This dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below).
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The State of Alaska makes no express or implied warranties (including warranties of merchantability and fitness) with respect to the character, function, or capabilities of the electronic services or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity, whether from the use of the electronic services or products, any failure thereof, or otherwise, and in no event will the State of Alaska's liability to the requestor or anyone else exceed the fee paid for the electronic service or product.
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