Installation and Configuration Guidance
IP ROUTERS INSTALLATION GUIDE 3G OTU
667/CI/45025/000 Rev 4 Unrestricted
11
3.
Installation and Configuration Guidance
3.1.
Site Selection Guide
In order to assist in appropriate site selection for 3G/4G installation, the user is referred to the
3G/4G Communications Site Selection Guide (667/AY/45025/002).
3.2.
Antenna Selection Guide
Siemens provide two types of antenna. The first is the Omni antenna which is normally
mounted on a traffic pole. Due to the mounting height the Omni installation is most likely to
provide the ‘best’ performance.
The second type, is a case (controller cabinet or VMS sign) mounted antenna. This antenna is
unlikely to perform as well as a pole mounted Omni due to the mounting height (<2m in the
case of a controller cabinet) and its antenna technology (patch antenna), which has a lower
gain (typically 0dBi as opposed to 3dBi for an Omni).
To assist installers in deciding the type of antenna to select, the sample signal strength; that
has been ascertained by working through the Site Selection Guide (see above), can be used.
Signal Guide
Antenna Guide
Strength
Quality
Condition
Omni Antenna
Case Antenna
RSSI dBm
CSQ
-109
2
Marginal
-107
3
Marginal
-105
4
Marginal
-103
5
Marginal
-101
6
Marginal
-99
7
Marginal
-97
8
Marginal
-95
9
Marginal
-93
10
OK
-91
11
OK
-89
12
OK
-87
13
OK
-85
14
OK
-83
15
Good
-81
16
Good
-79
17
Good
-77
18
Good
-75
19
Good
-73
20
Excellent
-71
21
Excellent
-69
22
Excellent
-67
23
Excellent