Path Loss (Lp); Table 7. Path Loss For Given Path Lengths (Miles) - ADTRAN 6000 Series System Manual

Section 2 Microwave Path Engineering Basics
Path Loss (L )
P
Path loss is the estimated attenuation between the transmit and receive antennas caused by signal
separation and scattering. The path loss is considered basic transmission loss over the microwave link. The
following expression calculates path loss:
⎛
⋅
L P = 20 log
⎝
where
f carrier frequency (Hz)
λ
carrier wavelength (c / f) (meters)
d path distance (meters)
c speed of light, free-space (meters)
or
L P =
where d is expressed in miles and f in GHz.
Path loss, as shown here, increases rapidly as either the path length increases or the carrier wavelength
decreases (which happens as the carrier frequency increases). Therefore, longer microwave paths naturally
experience more path loss than shorter paths. Likewise, higher frequency microwave communication
experiences more path loss than lower frequency microwave communication.
The path loss values for various path lengths for the TRACER 64x0 2.4 and 5.8 GHz systems are listed in
Table 7 (miles) and Table 8 on page 23 (kilometers).Values not listed in the tables can be interpolated from
those listed.
22
⎞
4πd
--------- - (dB)
⎠
λ
⋅
20 log 10 d ( )
96.6 + +

Table 7. Path Loss for Given Path Lengths (miles)

Path Length Path Loss (dB)
(miles)
1
2
3
4
5
10
15
20
25
30
35
Copyright © 2005 ADTRAN, Inc.
TRACER 6000 Series Integrated System Manual
f ( )
20·log
(dB)
10
Path Loss (dB)
at 2.4 GHz at 5.8 GHz
104 112
110 118
114 121
116 124
118 126
124 132
128 135
130 138
132 140
134 141
135 143
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