User's Guide

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D-620610-0-20 Rev B CONFIDENTIAL
Estimating RF Coverage
Table 6-11 shows estimated PLS for various environments that have different “clut-
ter” (that is, objects that attenuate the RF signals, such as walls, partitions, stairwells,
equipment racks, and so.).
By setting the path loss to the maximum allowable level (PL = APL), equation (3) can
be used to estimate the maximum coverage distance of an antenna connected to an
RAU, for a given frequency and type of in-building environment.
d = 10^((APL - 20log
10
(4πf/c))/PLS) (4)
For reference, Tables 6-13 through 6-17 show the distance covered by an antenna for
various in-building environments. The following assumptions were made:
• Path loss Equation (4)
• 6 dBm output per carrier at the RAU output
• 3 dBi antenna gain
• RSSI design goal = –85 dBm (typical for narrowband protocols, but not for
spread-spectrum protocols)
Table 6-11 Estimated Path Loss Slope for Different In-Building Environments
Environment Type Example
PLS for
850/900 MHz
PLS for
1800/1900 MHz
Open Environment
very few RF obstructions
Parking Garage, Convention Center 33.7 30.1
Moderately Open Environment
low-to-medium amount of RF
obstructions
Warehouse, Airport, Manufacturing 35 32
Mildly Dense Environment
medium-to-high amount of RF
obstructions
Retail, Office Space with approxi-
mately 80% cubicles and 20% hard
walled offices
36.1 33.1
Moderately Dense Environment
medium-to-high amount of RF
obstructions
Office Space with approximately
50% cubicles and 50% hard walled
offices
37.6 34.8
Dense Environment
large amount of RF obstructions
Hospital, Office Space with approxi-
mately 20% cubicles and 80% hard
walled offices
39.4 38.1