Decatur Electronics Genesis II Select - Patrol Harmonics; Radio Frequency Interference (RFI); Shadowing

Genesis II Select
™
User’s & Installation Manual
16/September/2015
48
7.2.6 Patrol Harmonics
In all police radar, when a patrol motor vehicle passes a large,
stationary object such as a road sign, building, or overpass, the
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Genesis II Select™ detects this condition and will not display
speeds which are generated by this overloading.
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patrol speed can also mimic this condition and will
be rejected. The target window will show an “_H_”
indicating that it is a patrol harmonic. To process this
type of target, simply increase or decrease your patrol
speed by at least 3 km/h.
7.2.7 Radio Frequency Interference (RFI)
The Genesis II Select™ contains an RFI detection circuit that detects
excess radio frequency energy. When stray radio frequency energy
reaches an excessive level, the system displays the RFI message
and stops processing and displaying speeds. The system resumes
normal operation when the RFI condition no longer exists. At that
time, any locked speeds will display again.
7.2.8 Shadowing
In Moving mode, the radar processes two speeds–patrol and
target. The stronger of the two, the patrol speed, is created when
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the pavement or terrain the motor vehicle is traveling on. However,
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from the ground, such as when the patrol motor vehicle is rapidly
overtaking a slow-moving 18-wheeler. Given a choice between
reading passing ground clutter or the large return signal generated
by the vertical expanse of the truck’s trailer, the radar might ignore
the ground speed and lock onto the stronger return signal. Rather
than receiving a true patrol speed, the radar reads the dierential
speed between the motor vehicle and the 18-wheeler. The
computer then subtracts this articially low speed from the closing
speed and assigns a higher speed to the target.