Page 387 - GuideFWA
P. 387
Pr{I < x} (percent)INTERFERENCE DISTRIBUTION - MACROBASES
99
90
Distribution of
70 interference on
50 arbitrary channel
30 Distribution of interference on
least-interfered FWA channel
10
1
-70 -65 -60 -55 -50 -45
x (dBm)
VERIFICATION (1): CHECKING THE AVERAGE
The probability density function for the distance between the victim receiver
and a randomly-positioned interference source (assuming uniform distribution
over area) is:
fd (r) = 2r
d 2 - d 2
max min
k rIf the received power is 2
then the average power from one source is
p?? dmax k 2kp??
N dmin r2 N
( ) ? ( )PRX 2 d 2 f (r)·
= d max - min dr = ln dmax - ln dmin
where ? is the density of active interfering channels (E/km2), ? is the fraction
of interfering transmitters “seen” by the victim receiver, and N is the number
of channels. This is easily checked against the Monte Carlo results.
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