Estimating RF Coverage
6-14
InterReach Unison Installation, Operation, and Reference Manual
CONFIDENTIAL
D-620003-0-20 Rev J
6.2.2
Coverage Distance
Use equations (1) and (2), on pages 6-12 and 6-13, respectively, to estimate the dis-
tance from the antenna to where the RF signal decreases to the minimum acceptable
level at the wireless device.
Equation (2) can be simplified to:
PL(d) = 20log(4
π
f/c) + PLSlog(d)
(3)
where PLS (path loss slope) is chosen to account for the building’s environment.
Because different frequencies penetrate partitions with different losses, the value of
PLS varies depending on the frequency.
Table 6-12 shows the estimated path loss slope (PLS) for various environments that
have different “clutter” (that is, objects that attenuate the RF signals, such as walls,
partitions, stairwells, equipment racks, and so on.)
For simplicity, Equation (3), Coverage Distance, can be used to estimate the coverage
distance of an antenna connected to an RAU, for a given path loss, frequency, and
type of in-building environment.
Table 6-12
Estimated Path Loss Slope for Different In-Building Environments
Environment Type
Example
PLS for
800/900 MHz
PLS for 1800
/1900/2100 MHz
Open Environment
with very few
RF obstructions
Parking Garage, Convention Center
33.7
30.1
Moderately Open Environment
with low-to-medium amount of RF
obstructions
Warehouse, Airport, Manufacturing
35
32
Mildly Dense Environment
with
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
with medium-to-high amount of RF
obstructions
Office Space with approximately
50% cubicles and 50% hard walled
offices
37.6
34.8
Dense Environment
with large
amount of RF obstructions
Hospital, Office Space with approxi-
mately 20% cubicles and 80% hard
walled offices
39.4
38.1
