tmo Flashcards
Precision refers to
measurements
accuracy refers to?
error
CE (Circular Error) is?
The geospatial position horizontal accuracy expressed in feet or meters at 90% probability
LE (Linear Error) is?
The geospatial position vertical accuracy expressed in feet or meters at 90% probability
CE and LE should be reported at ?
90% for targeting
Combined CE and LE determine the?
TLE
TLE (Target Location Error)
is the difference between the actual and expressed location of a target, TLE is intrinsic to the senser
HAE (Height Above Ellipsoid)
is the distance above or below an ellipse with a mathematically defined regular surface used to express a geometric model of the Earth
It was derived by using satellites to find the exact center of the Earth and creating an ellipse, a 3,930 mile radius from that point out to the 45 degree latitude lines.
MSL (Mean Sea Level)
Is a tidal datum that is arithmetic mean of hourly elevation observed over a specified 19 year cycle
It averages out tidal highs and lows caused by the changing effects of the gravitational forces of the sun and moon
The CE and LE category 1 standard for targeting is
6 m or 20 ft.
CEP (Circular Error Probable)
The geospatial horizontal accuracy expressed in feet or meters at 50% probability
CEP is intrinsic to the weapons system
GEOTRANS is?
A NCA validated program that allows converting geographic coordinates among a wide variety of coordinate systems, map projections, and datums
Datum?
A base reference for a coordinate system used to model the earth; there are two categories of a datum, Horizontal and Vertical
The vertical datum that is native to DPPDB is?
EGM 96
Photogrammetry is the ?
Art and science of making measurements from photographs / imagery
The basic types of imagery are?
Electro-Opitcal, Infra-Red and Synthetic Aperture Radar
The current imagery sources that can generate imagery used by the military are?
National technical means and the air breather theater systems:
Predator, IGNAT, Shadow, Global Hawk, P-3 Orion, U-2 Dragon Lady, E-8 JSTARS and Scan Eagle
Metadata?
Metadata allows the community to search and archive imagery
It also interfaces with other applications in geo-positioning
Most importantly, it provides geo-coordinates
What impact does light, shadow and image angle/obliqueness have on target marker placement and why
Obliquity and error can skew the coordinates of an image increasing the search time in terrain recognition.
In mountainous terrain, adverse look angle and obliquity can be challenging.
Shadows can help identify what you are looking at. Washout (too much light) can inhibit image resolution.
Mono Imagery and Stereo Imagery
Mono Imagery is a 2-D representation of a 3-D world
Stereo Imagery uses multiple image captures of the same area and allows us to look at the same thing from two different angles.
Stereo Imagery allows us to accurately determine feature height.
Image Obliquity
The difference between the reference elevation and the actual terrain elevation creating a possible horizontal error
Sensor location, altitude, look angle platform/ sensor accuracy and ground track are all ?
error sources for image obliquity
Key features or characteristics to properly employ terrain recognition are?
North arrow orientation, look angle, lakes and rivers, roads and paths, structures and buildings, vegetation and soil patterns, light and shadow
What is important to do in order for accuracy and currency of the imagery
have all of the current DPPDB for your area of operation and purge obsolete DPPDB
