Page 387 - GuideFWA

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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