...
Stations FS5 and FS6 in the Table 70 Error! Reference source not found.below have parameters in line with the Rec. ITU-R F.758 [22]. . FS1 and FS3 stations are representative of typically deployed PP FS stations. FS2 is representative of a longer than typical link operating mountainous terrain and hence an elevation angle of 5 degrees is appropriate[A1] , . FS4 is representative of a P-MP Hub station. P-MP subscriber stations are expected to have parameters similar to those valid for PP stations.
...
[A1]But no justificiation for FS3 which has a higher elevation angle of 10 degrees?
Table 7071: Recommended FS characteristics for FS vs FSS studies Anchor T070T071T070 T071
...