User Manual

VoiceXtender Modem Installer’s Guide
System Planning
Rev. A - 8/97 2-7
Table 2-2
Free Space Path Loss Between Two Isotropic Radiators
Distance
(kilometers)
Path Loss
@ 915 MHz
(L-Band)
1 92 dB
2 98 dB
3 101 dB
4 104 dB
5 106 dB
6 107 dB
7 109 dB
8 110 dB
9 111 dB
10 112 dB
15 115 dB
20 118 dB
25 120 dB
30 121 dB
35 123 dB
40 124 dB
50 126 dB
NOTE The calculation for attenuation using kilometers is:
attenuation in dB = [92. 4 + 20 LOG (distance in kilometers) + 20 LOG (frequency in GHz)]