User's Manual

61280.003L1-1B PAGE 23
4/12/99
I
NSTALLATION
PATH AVAILABILITY
The availability of a path can be expressed by:
availability = (1 - C x T x 2.5 x 10
-6
x f x D
3
x 10-F
/10
) x 100%
where
C is the climate factor
T is the terrain factor
f is the frequency in GHz
D is the path length in miles
F is the fade margin in dB
Climate factors are given below.
Climate
Climate Factor
Very Dry ..............
1
/
8
Temperate ............
1
/
4
Humid .................
1
/
2
Terrain factors are listed below
Terrain
Terrain Factor
Smooth .................... 4
Average .................... 1
Mountainous ...........
1
/
4
The nominal received signal level is -60 dBm. For help in link
planning, use the path loss calculation worksheet below.
- 91 dBm Minimum Signal Power
+ _______ Transmitter Feedline Loss
- _______ Transmitter Antenna Gain
+ _______ Path Loss
- _______ Receiver Antenna Gain
+ _______ Receiver Feedline Loss
+ _______ Required Fade Margin
= _______ (dBm) Transmitter Power Setting