Propagation Effects Handbook for Satellite Systems - DESCANSO ...

Step 4 The specific attenuation coefficients are determined by
interpolation from Table 6.3-3, with a polarizaiton tilt angle of
45° (circular polarization);
Step 5 The
Eq. (6.3-15
K= o.o163, a = 1.2175
attenuation exceeded for 0.01% of an average year, from
~ is;
Ao.ol = (0.0163) (42)1.217S(7.53) (0.771 )
= 8.96 dB
Step 6 The attenuation exceeded for other percentages is then
determined from Eq. (3.6-16);
% Attenuation (dB)
1.0 1.08
0.5 1.56
0.3 2.02
001 3(42
0.05 4.67
0.03 5.80
0.01 8.96
0.005 11.48
0.003 13.65
0.001
19.16
Figure 6.3-8 shows a plot of the resulting attenuation prediction
distribution, compared with three years of measured distributions
obtained with the CTS satellite (Ippolito 1979). The CCIR
prediction is seen to over-predict slightly for higher percentage
values, and to vastly under-predict for percentages below about
0.01%0
6-36