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simmus0300
2009-03-19, 09:08 PM
CAN ANYBODY TELL ME THE PING PONG H/O CAUSE AND SOLUTION ?

NILCTG
2009-03-19, 09:38 PM
Number of issues can trigger Ping Pong HO. Main reasons are:

Lack of dominance
Poor quality (due to poor frequency, HSN/MAIO plan etc)
Poor parameter value in CDD (such as wrong handover hysteresis value or penalty timer after emergency HO)

For solution my friend, first find out the root cause, and tailor the solution accordingly:).

*This is a very general answer to the question as these types of issues are context dependent.

ghassen
2009-03-19, 09:49 PM
Number of issues can trigger Ping Pong HO. Main reasons are:

Lack of dominance
Poor quality (due to poor frequency, HSN/MAIO plan etc)
Poor parameter value in CDD (such as wrong handover hysteresis value or penalty timer after emergency HO)

For solution my friend, first find out the root cause, and tailor the solution accordingly:).

*This is a very general answer to the question as these types of issues are context dependent.

pentime is only for cell reselection parameter not for handover my friend
this ping pong is mainly due to handover margin and timer to keep the mobile inside the cell area check also cell hierarchy and rules between cells

NILCTG
2009-03-20, 12:38 AM
pentime??

what is that? Your point is not clear to me!

ghassen
2009-03-20, 01:16 AM
pentime??

what is that? Your point is not clear to me!

penalty timer sorry but this the parameter in our database

NILCTG
2009-03-20, 01:18 AM
I an HW & E// Guy with little exposure to CDMA2000(Qualcomm), I think you are a NSN one:).

venom
2009-03-20, 02:41 AM
I an HW & E// Guy with little exposure to CDMA2000(Qualcomm), I think you are a NSN one:).

In GSM , it could be because of the swap in 900/1800 band or a partial swap in 2 sectors !!

Check the logs as well !

newbielinz
2009-03-20, 03:52 AM
CAN ANYBODY TELL ME THE PING PONG H/O CAUSE AND SOLUTION ?

In CDMA System, ping pong H/O usually happen at the border LAC or REGZONE, since LAC=REGZONE.

this can happen because:
- improper border planning, for example: main road become the border between LAC/REGZONE
- When LAC and REGZONE not similar then MS will make too many registration.
- Improper of parameter setting.

Solution:
- you can setting zone timer and other parameter to reduce ping pong effect
- You can change the border area
- You can change antenna setting (tilting, direction, etc)

Hopefully you this can help you,

Thank You,
Newbielinz

NILCTG
2009-03-20, 04:21 AM
Agree with both of u.

Mr.David
2009-03-24, 10:07 PM
Why don't u delete some unnecessary relation
if many unnecessary measurement frequency can affect PING PONG
but first you can compare PING PONG HO with Coverage Prediction

radenmohawk
2009-03-31, 10:21 PM
In siemens, you can adjust RXLEVMIN and HOM to avoid ping-pong HO

sh4r3d
2009-04-08, 01:43 AM
*maybe you have to check the handoff parameter:
Tx Power, T_ADD, T_Drop, T_COMP, and T_TDROP <-- on OMC database

if those parameter are too big you have to make it smaller, but not too small.
because if too small, there will be handoff failure. Just try to modify it for Optimum condition.

*and physical configuration:
Azimuth, and sectors Tilting

this physical adjustment will guide you to a better coverage in border cell. Avoid too wide cells slice area or vice versa.

cmiiw.

wireless.com
2009-04-08, 02:08 AM
Hi,

First I recommend an intensive drive test in that area and, after that, check the interference. Don't delete any neighborhood relationship and/or change parameters without find the root cause of problem... (I agree it is caused by absent of dominance cell or a island caused for multiple reflections, for example. It is not usual but I had this problem once…)

BR

maasricht
2009-04-08, 03:34 PM
Hi,

First I recommend an intensive drive test in that area and, after that, check the interference. Don't delete any neighborhood relationship and/or change parameters without find the root cause of problem... (I agree it is caused by absent of dominance cell or a island caused for multiple reflections, for example. It is not usual but I had this problem once…)

BR

I aggree with you. After drive test, I am 100% sure, need to be change azimuth / tilt or change cell to cell handover margin.

gprastomo
2009-05-28, 03:31 PM
Hi,

1. Check the neighbour, all neighbour should be defined properly
2. Check the drivetest coverage, it could be caused by no dominance server or interference, so adjust antenna is one of the solution
3. Parameter consistency check, HO margin, ADJRXLEVELMIN, neighbouring priority GSM DCS, etc. for example HO for DL RxLevel is set to -95 dBm so the AdjRXLEVELMIN should be more than -95 dBm eg -90 dBm

br

saridin
2009-05-28, 08:39 PM
sometimes its need to be checked phisically on site , and do some measurement about power of transmiter, and also don't forget to confirm with switching department to make sure about the LAC and CI, paerhaps no interference occured.

rheyra
2009-05-29, 01:55 AM
Hi All,
This is the best answer..
Thanks to gprastomo and add reputation for him...!!

BR//Rheyra


Hi,

1. Check the neighbour, all neighbour should be defined properly
2. Check the drivetest coverage, it could be caused by no dominance server or interference, so adjust antenna is one of the solution
3. Parameter consistency check, HO margin, ADJRXLEVELMIN, neighbouring priority GSM DCS, etc. for example HO for DL RxLevel is set to -95 dBm so the AdjRXLEVELMIN should be more than -95 dBm eg -90 dBm

br

gprastomo
2009-05-29, 04:51 PM
Haha,

Boss Rhey berlebihan :)


Hi All,
This is the best answer..
Thanks to gprastomo and add reputation for him...!!

BR//Rheyra

faisalusuf
2009-06-22, 06:31 AM
Ping pong means that a user MS is jumping b/w two cells. when i was doing RF planning course then i learned about C1 and C2 criterias. through this we define threshold for handover (gsm) accmin value should be choosen accordingly in it.

kais
2009-06-22, 07:08 AM
Ping pong means that a user MS is jumping b/w two cells. when i was doing RF planning course then i learned about C1 and C2 criterias. through this we define threshold for handover (gsm) accmin value should be choosen accordingly in it.

u must differenciate between cel reselection and HO.


to decrease ping pong HO u can optimise the parameter HO_margin or timer for pin pong HO

Djemai
2011-03-31, 09:01 PM
CAN ANYBODY TELL ME THE PING PONG H/O CAUSE AND SOLUTION ?

the main causes are :
cross feeder, or unavailable cross connexion into the BTS

mond86
2011-04-05, 06:19 PM
Solution:

Drivetest the area for possible overlapping of coverage, check where the HO was take place (Point of HO)
Delete unnecessary neighbors (Step by step)

Modify your HO offset (Step by Step)

Modify your Penalty Time (Increase) (step by Step)

If overlapping adjust your Cell Power first then drivetest again if it work revert your power and adjust now your antenna tilt (downtilt)

Note:Adjusting power might cause poor indoor penetration so it's not that recommended depending on the situation.

Consider if the area if highly populated and its terrain.. (Highly populated so to minimize drastic degradation of KPI) (Terrain so to be sure if its also affecting the handover to be consider on the penalty time modification.. to long penalty might cause drop call on a hilly area or poor quality due to to long cell Handover..


If it help anyone don't forget to give me Thanks and Reputation

Thanks