antenna supervision

Antenna SupervisionPREPARED BY :- AVISHEK SAHA
Antenna Supervision
Antenna Supervision Threshold (RBS3206 and RBS3518, P7.1 version)
Antenna Supervision
Antenna Supervision Type
DC Resistance
VSWR
If there is no ASC, DC resistance could be monitored. Anyway, some FU types support VSWR monitor. You can find in Alex as below from RBS3206
The FUs 850 MHz, 900 MHz, 1900 MHz, 1700/1800 MHz and 1700/2100 MHz also provide supervision of the antenna by means of Voltage Standing Wave Ratio (VSWR) on branch A.
© Ericsson AB 2009 | Ericsson Internal | X (X) | Date
Antenna Supervision
Antenna Supervision Type (Cont.)
So, we have to check what FU type and support VSWR monitor. It mentions in Alex as below
The full name of the Filter Units are FU12 <frequency>.
Example: FU12 19 (1900 MHz).
Example: FU 12 21 (KRC 118 17/1) supports only 2100MHz; hence, it does not support VSWR monitor without ASC as mention in Alex.
Summary: we have to check type of FU for RBS3206 and for RBS3518 we can check in Alex also. If FU does not support VSWR monitor, we must add ASC to monitor VSWR. Otherwise, we can check only DC resistance like FU 12 21 (KRC 118 17/1) .
Antenna Supervision
Formula and calculation
After we understand hardware, we can set antennaSupervisionThreshold in AntennaBranch MO as below
When DC resistance supervision is used the threshold maps to a resistance (R),
R = (101-antennaSupervisionThreshold)*0.15 ohm
When VSWR supervision is used the threshold is mapped to a return loss (RL),
when performed by ASC:
when performed by FU:
Please see antennaBranch MO for full information
Antenna Supervision
Antenna Supervision | Ericsson Internal | 2010-08-10 | Page *
Case:FU 12 21 (KRC 118 17/1)
FU 12 21(support only 2100 MHz) does not support VSWR supervision, only has DC resistance.
DC resistance method is resistance (R ) measuring.
AntennaSupervisionThreshold parameter is used to be the threshold of resistance. If resistance more than the threshold, antenna alarm shows.
AntennaSupervisionThreshold range = 0,1-100.
R = (101-antennaSupervisionThreshold)*0.15 ohm
Antenna Supervision
FU 21
So, resistance = ∞ (V= I/R)
Antenna Supervision
FU 21
TOTH9D> lh ru fui get devstat
100629-14:17:29 10.217.114.113 7.1z RBS_NODE_MODEL_L_10_9_COMPLETE stopfile=/tmp/17770
=============================================================================================
$ lhsh 001200/port_0_dev_3 fui get devstat
0012p0d3: Board: fuHw: KRC 118 17/1 R3A, RU-FU cable: connected, temp: 27.0 deg C, sv: on, svTmaDegrad: on, gainTempComp: on
0012p0d3: Branch A:
0012p0d3: mode: {ModeAnt}
0012p0d3: feedPow: lowPow
0012p0d3: svCtrl:
0012p0d3: Aux max current consumption supervision: Off
0012p0d3: Aux short circuit supervision: Off
0012p0d3: Aux equip. min voltage/current supervision: Off
0012p0d3: Aux TMA LNA supervision: Off
0012p0d3: Internal LNA supervision: On
0012p0d3: Rx cable supervision: -
0012p0d3: txFreq: 0 kHz
0012p0d3: sensitivity: 100 percent
0012p0d3: volt: 0 mV
0012p0d3: curr: 120 mA
0012p0d3: svCtrl:
0012p0d3: Aux max current consumption supervision: Off
0012p0d3: Aux short circuit supervision: Off
0012p0d3: Aux equip. min voltage/current supervision: Off
0012p0d3: Aux TMA LNA supervision: Off
0012p0d3: Internal LNA supervision: On
0012p0d3: Rx cable supervision: -
0012p0d3: txFreq: 0 kHz
0012p0d3: sensitivity: 100 percent
0012p0d3: volt: 2919 mV
0012p0d3: curr: 0 mA
Antenna Supervision
Case:RRUW in RBS3518
- VSWR measurement support
$ lhsh 000900/port_0_dev_6 fui get vswr
0009p0d6: Supervision is on
We can convert to VSWR as formula
VSWR = (1+10^(-RL/20))/(1-10^(-RL/20))
Anyway, PLM mentioned that VSWR monitoring fully support and verified in W10A. So, it recommend to use with W10A or later version.
Antenna Supervision
Alarm after set antenna supervision
This is example for RBS3518(no ASC) showed alarm after set antenna supervision threshold.
Tip: It takes time to wait until alarm appears (maybe 10 – 15 minutes).
Antenna Supervision
Antenna Supervision

antenna supervision

Documents