Planning An Dcs 6000 Digital Infra-Rectangular Footprints; Red Radiation System - Danish Interpretation Systems DCS 6000 User Manual

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3.4 Planning an DCS 6000 Digital infra-

red radiation system

Determining the optimal number of infra-red
3.4.1 Rectangular footprints
radiators required to give 100% coverage of a
hall can normally only be done by performing a
site test. However, a good estimation can be
made by using
footprints'.
Figure 3.4-A and Figure 3.4-B show what is
meant by a rectangular footprint. As can be seen,
the rectangular footprint is smaller than the total
footprint. Note that in Figure 3.4-B the 'offset' X
is negative because the radiator is actually
mounted beyond the horizontal point at which
the rectangular footprint starts.
The guaranteed rectangular footprints for
various number of carriers, mounting heights
and mounting angles can be found in section
10.8. The height is the distance from the
reception plane and not from the floor.
Figure 3.4-A A typical rectangular footprint for a mounting
angle of 15°
14
'guaranteed rectangular
User Manual DCS 6000 Digital IR System rev H.docx
Figure 3.4-B A typical rectangular footprint for a mounting
Guaranteed rectangular footprints can also be
angle of 90°
calculated with the footprint calculation tool
(available on the documentation CD-ROM). The
given values are for one radiator only, and
therefore do not take into consideration the
beneficial effects of overlapping footprints. The
beneficial effects of reflections are also not
included. As rule of thumb can be given for
systems with up to 4 carriers, that if the receiver
can pick up the signal of two adjacent radiators
the distance between these radiators can be
increased by a factor 1.4 approximately (see
Figure 3.4-C).
The effect of overlapping footprints
Figure 3.4-C
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