CTP Systems CTPhone 1900, Applications Manual

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2-14 DOC00101-01
CTPhone 1900 System Planning
Fading
Fading refers to the attenuation caused when a signal is reflected and a
receiving antenna receives multiple instances of the signal.
CTPhone base stations are designed with multiple antennas and the
capacity to choose the antenna best suited for carrying the strongest sig-
nal. This design minimize chances of fading.
You should place base stations so that signals begin their travel with a
clear line of sight as illustrated in Figure 2-11. This limits the effect of signal
fading.
Examples
Example 1 — Centralizing Base Stations
Figure 2-12 illustrates a site with factory and adjoining office area. Both
base stations are placed in the manufacturing area to accommodate the
greater number of users in that area. However, base station BS2 is placed
closer to the office area to provide coverage in the office area and maxi-
mize line of sight through the doorway. This is especially important if the
wall between the office and manufacturing areas is concrete.
To satisfy guidelines 1 and 2, the base stations are mounted on the ceil-
ings and away from any potential obstructions to the antennas.
If there was another area to the left of the manufacturing area, moving the
base station BS1 to the left would probably allow support for users in that
area as well. If the manufacturing area does not obstruct base station
antennas, their broadcast range will be greater.
Figure 2-12. Centralized Base Station Placement
manufacturing area
offices
320’
168’
co
nc
re
te
c
onc
ret
e
front door
140’
200’
(32 CTPhone
handset users)
BS1
BS2
(ceiling
mounted)