Step 4.2: Check the reflection diagrams
The reflection diagram for each sensor can be accessed via the sensor configuration page by
clicking on the corresponding "reflection" button (Fig. 3.9).
A reflection diagram is a graphic representation of a 25 [ms] scan, where the signal strength
[dB] is plotted against the measurement distance [m]. A scan consists of one up-sweep
(increasing frequency, blue curve) and one down-sweep (decreasing frequency, red curve).
Often several peaks are visible in a reflection diagram as shown in Fig. 3.9. This is caused
by the multiple signal reflections between radar, water surface and any objects within the
radar foot-print. The leftmost peak is generated by the so called internal reflection. The
signal processing takes this phenomenon into account such that it does not have a negative
e
ff
ect on the measurements.
Figure 3.9: The reflection diagram of one of the three sensors.
Based on the defined range maximum and minimum values, the WaveGuide system shows
the applied boundaries using vertical green lines. A horizontal green line shows the min-
imum accepted reflection strength (the value set as the Signal Minimum [dB] parameter).
The three green lines together form a region in which a measurement is accepted, and any
result outside of it is ignored.
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