Wave Wireless Networking SC5800, User Manual, Page: 36 / 108

SPEEDCOM SC5800 User Manual
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5.3.2 Alignment Procedure
1. Locate the far site and point the antenna to the antenna at the far site, as
accurately as possible using binoculars or a compass.
2. Connect the multimeter to the RSSI connector on the Outdoor Unit using the
supplied RSSI test cable and set the multimeter to measure volts.
3. Check the RSSI level and refer to the figure below for received power level.
4. Align the antenna until the maximum RSSI is attained.
5. Secure the antenna.
6. Measure the RSSI leve l and record the value (see Section 5.7, SC5800Test
Record, page 37).
7. Compare with the value with that calculated for the link (i.e., using the
pathloss calculation done when planning the link).
Figure 5. Typical Version 2 OU RSSI Voltage as a function of RF input power
level
-80dBm Average 0.436 ± 0.029 V: MIB RSSI 95 ± 1 dBm (see comment below)
-30 dBm Average 1.333 ± 0.047 V: MIB RSSI 54 ± 2 dBm (see comment below)
The MIB lists a dBm value representative of the received signal level. The value
detected is representative of the level that would be measured should a CW signal
be input at the Outdoor Unit's Diplexer RF Port - a Spread Spectrum signal will
appear to be 20 dB lower. The NMS makes an adjustment for this by using a 20 dB
offset (addition to the Indoor Unit MIB-indicated value).
The front panel RF Link LED, the Received Signal Strength Indicators (RSSI : on
NMS, via SNMP or as an Electrical signal on the Outdoor Unit), Carrier-detect
(NMS, SNMP) and Frame Lock (NMS, SNMP) indicators are available to assist with
link installation and alignment.
The front panel RF Link LED, the Received Signal Strength Indicators (RSSI: on
NMS, via SNMP or as an Electrical signal on the Outdoor Unit), Carrier-detect
(NMS, SNMP) and Frame Lock (NMS, SNMP) indicators are available to assist with
link installation and alignment.
5.3.3 Set Transmitted Power Level
It is good practice to match received power levels by adjusting transmitted powers if
co-located systems are being installed. This is important to avoid interference
between co-located systems. An attenuator can be fitted between the Outdoor Unit
and the antenna if the power level cannot be sufficiently reduced. The dBm output at
the OU N-type connector (socket) levels are set via the NMS or using a SNMP
Management application.