Amplitude Tracking; Full-Tank Detection; Figure 2-4 Radar Impulse Reflection Model - Honeywell SmartLine SLG 700 User Manual

Although the algorithms are tolerant of signal amplitude variation, a good match is important
to discern the true level signal from that caused by obstacles near the probe or secondary
reflections. Both the DTM and the advanced display module show the signal quality, a
measure of the match between radar pulse model and acquired echo curve.

Amplitude Tracking

Release R102 introduced an additional feature to improve level tracking under difficult
conditions or when the medium attenuation is not well known. The amplitude tracking feature
(off by default) enhances the user specified pulse model information using historical
measurement data. It can improve the quality of the match when there are slowly varying
conditions in the tanks, such temperature variations, vapor density changed, turbulence or
even dirt build up on the probe. Amplitude tracking is not a substitute for model tuning and
will not track signals more than 35% different in amplitude from those expected. It should be
noted that tracked amplitudes are periodically saved to permanent memory. When the sensor
starts up it will first attempt to locate the levels using the tracked signal amplitudes and if this
fails, will revert to the initial amplitudes when the sensor loses power since it is impossible to
predict whether the conditions that caused the pulse to change (say turbulence) exist when the
sensor is repowered.

Full-tank Detection

This feature enables the transmitter to perform additional analysis on the data in the region
near the reference plane where the product reflections become mixed with reflections from
the physical mounting components such as a flange or nozzle. This additional analysis allows
the transmitter to detect the presence of product in this region even if the shape of the product
reflections deviate significantly from the expected shape. This option should only be enabled
if a recently captured Field or Obstacle background is in use and the Dielectric Constant of
the Upper Product is above 12. It should not be enabled for products with low Dielectric
Constants or when the Built-in background type is being used.
Revision 8

Figure 2-4 Radar Impulse Reflection model

SLG 700 SmartLine Level Transmitter User's Manual
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