User's Manual

Designing a Fusion Wideband Solution
Page 84 InterReach Fusion Wideband Installation, Operation, and Reference Manual
© 2015 TE Connectivity D-620616-0-20 Rev K • TECP-77-044 Issue 9 • March 2015
Equation 2—Path Loss Equation
In-building path loss obeys the distance power law in Equation 2:
PL = 20log
10
(4πd
0
f/c) + 10nlog
10
(d/d
0
) + X
s
where:
• PL is the
path loss at a distance, d, from the antenna
• d = the distance express
ed in meters
• d
0
= free-space path loss distance in meters
• f = the operating frequency in Hertz.
• c = the speed of light in a vacuum (3.0 × 10
8
m/sec).
• n = the path loss exponent and depends on the building “clutter” and frequency of op
eration
• X
s
= a normal random variable that depends on partition material and geometries inside the
building and is accounted for by the log-normal fade margin used in the downlink RSSI design
goal calculation.
As a reference, Table 71 provides estimates of signal loss for some R
F
barriers
1
.
1 Rappaport, Theodore S. Wireless Communications, Principles, and Practice. Prentice Hall PTR, 1996.
Table 71. Average Signal Loss of Common Building Materials
Partition Type Loss (dB) Frequency (MHz)
Metal wall 26 815
Aluminum siding 20 815
Foil insulation 4 815
Cubicle walls 1.4 900
Concrete block wall 13 1300
Concrete floor 10 1300
Sheetrock 1 to 2 1300
Light machinery 3 1300
General machinery 7 1300
Heavy machinery 11 1300
Equipment racks 7 1300
Assembly line 6 1300
Ceiling duct 5 1300
Metal stairs 5 1300