Sunday, 4 October 2015

FDD-eNodeB-GL dual model site,LTE & GSM share the same PA, The power of PA is abnormal

 Incident Description (Incident Phenomena)
  GL dual model siteLTE & GSM share on the same PA, There is no related alarm showed on the EMS, And the power of PA is abnormal.
The type of the RRU for the GL dual model cell is R8882 GUL1812 BBU board is BPL0+FS5+CC16Between BBU and RRU the connection is fiber though FS5.
 Networking Environment
 Problem Cause Analysis
  The reason caused Cell PA is abnormal
l  PA of the cell is blocked
l  Bad transmission cause S1 is abnormal
l  The cell is blocked
l  The hardware don’t support GL dual model configurationthe software version of the site don’t support this function
l  Quality of the hardware issue and physical connection fault.
l  Irrational parameter
 Solution
 
1.         Query the CELL and PA status
The cell and PA status is normal
2.         Quality of hardware transmission physical connection checking.
After checkthere is no related alarm and issue about hardware transmission physical connection.
3.         Confirm the supportable ability of the hardware and software
Confirmed from the related export ,the supportable ability of the hardware and software is competent.
4.         Parameter check
According to plan data to check all the parameters . radio parameters of GSM cell and LTE CELL configuration is normal . and the LTE cell is 2T2R with 20M bandwidth.
After check public parameters , the related optical slot rate of the cell on FS5 board is 2.5G
a: without modify the radio parameters , the related optical slot rate of the cell on FS5 board should be modified to 3GAnd PA of the cell is normal ,service is normal.
b: without modify the public parametersthe configuration of the LTE cell should be downgrade to 10M bandwidth with 2T2RAnd PA of the cell is normal ,service is normal.
 Summary and Notes
 
BPL0 board does not support IQ compress when the related optical slot rate of the cell on FS5 board is 2.5G ,At most it support 16 AXC resources, But the bandwidth is based on BPL0, only the LTE cell for 2T2R with 20M bandwidth At least 16 AXC resources is neededBut and still need more AXC resources for GSM cell. It’s over range.
   On the situation of AXC resources needed is more than support, It should be downgrade the cell configuration or upgrade the configuration of the equipment.

Budi Prasetyo

About Budi Prasetyo

All About LTE

Subscribe to this Blog via Email :