Ranging Conditions - Safran LRF 6042 Manual

LRF 6042 Integrator Manual

2.2 Ranging Conditions

In general, two kinds of ranging conditions apply:
 Range capability: The possible laser range performance on a target under best conditions.
 Range performance: The guaranteed range performance on a defined target under defined
conditions.
The range performance depends on visibility, target size and albedo (reflectivity) and is calculated relating to
a certain detection probability e.g. 90%.
Visibility
Visibility is the greatest distance from an observer where a prominent dark object against the sky on the
horizon can be seen and identified by an unaided eye. Good visibility means a clear sky, whereas bad
visibility would be Fog, snow, dust, sand, smog and rain conditions.
Sunlight
Bright backlight or high sunlight reflections on the target can reduce the range performance.
Object Size
A typical target size for range performance comparison is the NATO target with a similar size to the front of a
tank. The size of a NATO target is 2.3 m x 2.3 m. Additionally the LRF performance is defined on a man size
target with a size of 1 m x 1 m.
Object Albedo
The albedo is the surface's reflectivity of an object, or rather is the ratio of reflected to incident light in the
wavelength of the LRF Module (1550 nm).
Object Orientation
The angle of the target surface perpendicular in relation to the laser beam is also important. Similarly, targets
with a very high albedo can give only a very small reflection towards the LRF module when the reflected
laser radiation is not at 0° and reflected away, e.g. on water or pitched roofs.
Object Hardness
The accuracy of "soft objects" like snow, smoke, clouds etc. depends on the condition of the object itself.
Mirror-like objects
The accuracy and range performance on mirror-like objects such as water, glass surfaces or reflective traffic
signs can cause incorrect measurements or no measurement results at all.
INTEGRATOR MANUAL LRF 6042 917657- A
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Figure 6: Example of a 0.5 mrad laser beam size on target
Public: 02.2022
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