Measuring Signal Performance
Tsunami
®
MultiPoint 10200 Series - Antenna Installation Guide
25
2. Add the gain of the antenna you will be using. The total is the
EIRP
(Equivalent Isotropically Radiated Power).
3. Determine the path loss of the microwave link by using the mathematical formula of
L
p
,
.
4. Add the gain of the antenna on the second side of the link.
5. Subtract the total loss of all transmission elements between the antenna and the radio on the second side of the link. The
result is the
Received Signal Level
(RSL).
6. For details on the receive sensitivity and data rate values used for the wireless link, for details refer to
Tsunami
®
MultiPoint
10200 Series Hardware Installation Guide
.
7. Subtract this value from the Received Signal Level; this is the
Fade Margin
.
:
•
The RSL must be higher than the Receiver Sensitivity plus the Fade Margin for a good link. The amount of Fade
Margin indicates the reliability of the link. The more the Fade Margin, the more reliable is the link.
The results of this link budget calculation are very important for determining any potential problems during installation. If you
have calculated the expected RSL, you can verify that it has been achieved during installation and troubleshooting.
Tabulated below is the relation between the
Distance
and
Link Budget,
for a selected frequency:
Reference Frequency: 5600 MHz Center Frequency for Europe
Link Budget
(dB)
Distance
(m)
Fresnel
Zone (m)
Link Budget
(dB)
Distance
(m)
Fresnel
Zone (m)
Link Budget
(dB)
Distance
(m)
Fresnel
Zone (m)
61
4.8
0.3
91
151
1.4
121
4.8
8.0
62
5.4
0.3
92
170
1.5
122
5.4
8.5
63
6.0
0.3
93
190
1.6
123
6.0
9.0
64
6.8
0.3
94
214
1.7
124
6.8
9.5
65
7.6
0.3
95
240
1.8
125
7.6
10.1
66
8.5
0.3
96
269
1.9
126
8.5
10.7
67
9.5
0.4
97
302
2.0
127
9.5
11.3
68
11
0.4
98
339
2.1
128
10.7
12.0
69
12
0.4
99
380
2.3
129
12.0
12.7
Link Budget
(dB)
Distance
(m)
Fresnel
Zone (m)
Link Budget
(dB)
Distance
(m)
Fresnel
Zone (m)
Link Budget
(dB)
Distance
(m)
Fresnel
Zone (m)
70
13
0.4
100
426
2.4
130
13.5
13.4
71
15
0.5
101
478
2.5
131
15.1
14.2
72
17
0.5
102
537
2.7
132
17.0
15.1
73
19
0.5
103
602
2.8
133
19.0
16.0
74
21
0.5
104
676
3.0
134
21.4
16.9
75
24
0.6
105
758
3.2
135
24.0
17.9
76
27
0.6
106
850
3.4
136
26.9
19.0
77
30
0.6
107
954
3.6
137
30.2
20.1
78
34
0.7
108
1071
3.8
138
33.9
21.3
79
38
0.7
109
1201
4.0
139
38.0
22.6
80
43
0.8
110
1348
4.2
140
42.6
23.9
81
48
0.8
111
1512
4.5
141
47.8
25.3
82
54
0.8
112
1697
4.8
142
53.7
26.8
83
60
0.9
113
1904
5.0
143
60.2
28.4
84
68
1.0
114
2136
5.3
144
67.6
30.1