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4. LEVEL OF DESENSITIZATION
The report [1] assumed a 1 dB victim desensitization value – is this correct?
4.1. LMNQ VIEW
Coverage vs Noise Rise
100
90
80
70
60
50
40 20
30 30
40
20
10
0
0 0.5 1 1.5 2 2.5 3
Rise in Noise (dB)
Figure 4.1 Percent Reduction in Cell Area Vs Desensitization
Received power = a - k * log(R) (dB) where a is a constant and k is the propagation
constant
Desensitization D (dB) = required increase in Desired Received Power to overcome the extra
Therefore = (a – 10 * k * log(Rnew)) - (a – 10 * k * log(Rorig)) = 10 * k * log
(Rorig/ Rnew)
Rorig/ Rnew = 10(D/10k)
If coverage = p * R2
Then change in Coverage = (p * Rnew2 ) / (p * Rorig2) = (Rnew / Rorig)2 = 10(-2*D/10k)
Thus, the change in coverage (%) is given in Figure 4.1 and in Table 4.1.
Inter-American Telecommunication Commission 197
