Data Sheet

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RFbeam Microwave GmbH | Schuppisstrasse 7 | CH-9016 St. Gallen | www.rfbeam.ch | K-LD 2 | data sheet 02 / 2020 Revision C | Page 12 / 25
Speed limitation and ranging
The K-LD2 features the possibility to easily filter out
slow and fast speeds by setting speed limits with the
parameters D04 & D05 over the command set. The
limits are independent of each other and can be used
stand-alone.
The whole FFT can also be divided into two speed
ranges with the parameter D06. When the speed ran-
ge threshold is set, the detection algorithm decides
in which speed range (high or low) the detection was
Figure 11: Speed limitation and ranging overview
The usage of the speed limits and the speed
range threshold makes it very easy to divide
objects into two speed classes
found and latches it to the detection register or, if it is
configured to signal the speed range (see parameter
S06), to the miscellaneous output.
Micro detection
The micro detection is a feature to detect very slow
speeds in short range applications. It takes advantage
of an algorithm that analyses the DC bin of the FFT to
detect very slow speeds. The micro detection is inde-
pendent from the normal detection algorithm and al-
ways enabled.
If a slow movement generates a signal magnitude
that is higher than the adjustable micro detection th-
reshold (see parameter D07) the micro detection flag
in the detection register goes to high (see parameter
R00).
The miscellaneous output can be configured to si-
gnal the micro detection over the parameter S06. This
gives the host the possibility to directly trigger to a valid
micro detection.
Furthermore, it is possible to retrigger the detection
algorithm over the micro detection feature (see para-
meter S0D). If this feature is enabled, the detection al-
gorithm first requires a valid detection and then, if there
was a valid micro detection, it will retrigger the hold
time. If the hold time has elapsed because there was
no detection or micro detection, the detection goes to
low and needs again a valid detection before the micro
detection is used to retrigger the hold time.
The algorithm computes the micro detection
flag forevery sampled frame, independent of
the hold timesetting.
The covered speed range that is analysed by
themicrodetection feature depends on the
sampling rate (see parameter S04), because
the content oftheDC bin changes with the
sampling rate.