ALM-4178 Diversity receive channel alarm

Description

The alarm is reported when the gain of the diversity receive path smaller than that of the diversity receive path exceeds the relevant threshold.

Attribute

Alarm ID	Alarm Severity	Alarm Type
4178	Warning	Fault

Parameters

ID	Name	Meaning
1	Site No.	Number of the site where the faulty board or module is located Value range: 0-2047
2	Board Type	Number of the type which the faulty board belongs to. 65:DTRU/GTRU/DDRM 88:DRRU 92:DRFU 96:MRRU 100:MRFU 101:GRFU 102:GRRU 151:QTRU
3	Board No.	Number of the fault board
4	PassNo	Number of the passage where the faulty board is located.
5	SubLink No.	Alarm sub-category number 255:None
6	Cell Index	Index of the cell where the board or module is located 0-2047: Cell index of the faulty cell in the data configuration 65535: None
7	Site Type	Type of the site where the faulty board is located. 12:BTS3012; 13:BTS3006C; 14:BTS3002E; 15:BTS3012AE; 16:BTS3012 II; 17:DBS3900 GSM; 18:BTS3900 GSM; 19:BTS3900A GSM;
8	RackNo	Number of the rack where the faulty board is located.
9	BoxNo	Number of the subrack where the faulty board is located.
10	SlotNo	Number of the slot where the faulty board is located.
11	Site Name	Site Name
12	Alarm Attribute	Alarm Character 0:Normal 1:Transient Count

Impact on the System

When this alarm is generated, the uplink receive sensitivity of the faulty TRX is deteriorated, and the coverage area of the faulty TRX is shrinked. If the faulty TRX is the BCCH TRX, the coverage area of the cell is shrinked. In this case, the success rate of handovers in the cell drops.

System Actions

None.

Possible Causes

The TRX is configured in Single Antenna Double Receiver mode. The diversity antenna is not installed, and only the single jumper is available.
The connection of the RF cable is loosened, broken, or damaged.
The TRX board is faulty.

Procedure

Check if the configuration of the TRX is in Single Antenna Double Receiver mode.
Y = > Perform combining. No further action is required.

N => Go to step 2.
Check if only the single jumper is available.
Y = > Perform combining. No further action is required.

N => Go to step 3.
Check the RF cable connection between the TRX, feeder, and antenna. If the cable is loosened, tighten the connector. If the cable is damaged, replace the cable. Check whether the alarm is cleared.
Y => Alarm handling is complete.

N => Go to step 4.
Replace the TRX. Check whether the alarm is cleared.
Y => Alarm handling is complete.

N => Contact Huawei Customer Service Center.