Step 4.2: Check reflection diagrams
The reflection diagram for each sensor can be accessed via the sensor configuration page by
clicking on the corresponding "reflection" button (Fig. 3.7).
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. 3.7. 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
effect on the measurements.
Figure 3.7: The reflection diagram gives a graphical representation of the
radar signal received in a single measurement.
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.
Step 4.3: Check measurements
On the ’Dashboard’ page, the heave parameter shows data measured during the last 1, 3 or
10 minutes. Please inspect the available heave graph to visually confirm the measured data.
From the same menu all calculated parameters are available. Please take into account that
it can take up to 10 minutes to gather enough raw data to calculate some of the parameters.
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