AJAX DualCurtain Outdoor, Руководство пользователя

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mode.
Protection against false triggerings
To lter false alarms, DualCurtain Outdoor applies ELSA (Extended Live Signal
Analysis) — a three-stage software algorithm that analyzes the signals received
from two narrow-angle IR sensors of the same optical system.
1. Form analysis
The shapes of both IR sensor signals should indicate the crossing of the secured
zone. In any direction: either perpendicular or along the direction of the detector
optics. At the same stage, a correction for the signal intensity is made to take into
account the distance from the sensors and the size of the object.
2. Patterns comparison of
The signal amplitudes are veri ed with the pattern database. To create it, we
analyzed thouthands of test triggers of curtain detectors on people, animals, lights,
and other natural sources in various weather conditions. Signal patterns should be
the same or insigni cantly different from those typical to humans.
3. Time veri cation
When signals from both IR sensors match the conditions: this is motion and it is
typical for a human, the ELSA algorithm compares the time frames of the signals —
whether the upper and lower sensors detected the motion synchronously.
The system raises an alarm if all three conditions are met. The ELSA algorithm
takes less than 1 second to render a “threat” or a “false alarm” verdict.
Near area detection
Typically, outdoor curtain detectors have a blind spot near the enclosure. Its size
depends on the height of the installation, the type of the detector, and the motion