Number of HO attempts decrease after swap

[kyokuman]

Hi all,

After swap from Siemens to Huawei, HO attemps decreased by half!

Parameters mapping was made so that all same thresholds, stragegy etc... was kept so that we have same behavior.

I can't see any reason having much less HO attempts.
All other KPIs are ok. Traffic is same, Drop call rate is good even better than before.

Anybody got an idea?

Thanks

[RF engineer]

Hi all,

After swap from Siemens to Huawei, HO attemps decreased by half!

Parameters mapping was made so that all same thresholds, stragegy etc... was kept so that we have same behavior.

I can't see any reason having much less HO attempts.
All other KPIs are ok. Traffic is same, Drop call rate is good even better than before.

Anybody got an idea?

Thanks

probably before site had feeder swap before swap every thing were ok.

BR

[kyokuman]

Hi,

I forgot to tell that it is the case for all my sites!

ALL the sites have much less HO !

Tx

[bokobi]

Huawei 2G or 3G

can you check the number of call ended on 2G

[kyokuman]

It is 2G.

ANd for info, there is no HO to 3G allowed.

[tomrf]

Hi all,

After swap from Siemens to Huawei, HO attemps decreased by half!

Parameters mapping was made so that all same thresholds, stragegy etc... was kept so that we have same behavior.

I can't see any reason having much less HO attempts.
All other KPIs are ok. Traffic is same, Drop call rate is good even better than before.

Anybody got an idea?

Thanks

check HO target parameter,if you're in 2G and 1 MSS:
- check if BSIC, bcch target was created correctly in BSC
if source & target cell in different MSS:
-check if BSIC, bcch target was created correctly in BSC, also LAC target was created on MSS

happy optimizing :)

[RF engineer]

Hi,

I forgot to tell that it is the case for all my sites!

ALL the sites have much less HO !

Tx

Dear

Easy way to see what are the reasons make HO reduced , it is better to see HO reason before and after due ( Quality,Rx level,better ,,,,,,) u may find some things.

BR

[kyokuman]

Hi and Thanks for replies!

However I ve checked everything as you proposed. Everything is defined properly.
And if there was wronf declaration of neighbors information (Lac, BCCH...), I would see it in the KPIs, right?


I was more thinking that Huawei has a different algotithms, where BTS simply sends MRs to BSC which then makes the ranking list (16 bits), and triggers the HO
Unlike Siemens, where BTS seems to decides about triggering HO or not. Indeed, the BTS sends Handover condition indication to the BSC. When BSC receives this message, counter "HO request" is incremented.

What do you think?

[RF engineer]

Hi and Thanks for replies!

However I ve checked everything as you proposed. Everything is defined properly.
And if there was wronf declaration of neighbors information (Lac, BCCH...), I would see it in the KPIs, right?


I was more thinking that Huawei has a different algotithms, where BTS simply sends MRs to BSC which then makes the ranking list (16 bits), and triggers the HO
Unlike Siemens, where BTS seems to decides about triggering HO or not. Indeed, the BTS sends Handover condition indication to the BSC. When BSC receives this message, counter "HO request" is incremented.

What do you think?

For huawei BSC is the owner because in 2G donot have kind of synchronization that each BTS talk to each other and decide the HO .

BR

[kyokuman]

But it does not explain the diminution of HO attempts. Am I right?

[alg_optim]

As RF Engineer said check HO reason and check which one decreased ( better Cell , Level , Quality ,..... )


B.R
Alg_optim

[kyokuman]

Thanks but they all decreased, as I said.

[RF engineer]

Thanks but they all decreased, as I said.

So it is better to escalate to huawei in order to find u the problem .

BR

[kahnoie]

Maybe the channel capacity got augmented after the SWAP and possibly there was directed retry forced from the old transmitters. With added capacity, these handovers would have reduced.
Please verify this and let us know.

[kyokuman]

Hi,

I asked Huawei. They have been investigating for several days, and they still don't know.

There was no additional capacity after SWAP.

:(:(:(:(:(:(:(:(

[alg_optim]

the emergency HO threshold was mapped correctly ?

[kyokuman]

Only Badqual HO was activated as Emergency HO.

So we did the same for huawei.

There are currently very few Badqual HO, as before.

95% of HO are PBGT, as it was before.

[alg_optim]

check HO from 900 to 1800 If you have dual band network before and after swap

B.R

[kyokuman]

There is only 900.

[sesunguts]

What BTS type before and after swap? is it from tradisional TRX to MCPA type? Are you already check coverage before and after are same?

[kyokuman]

Power was mapped.

[mohyedeen_alkousy]

Hi
are u using Huawei Algorithm I or Huawei Algorithm II ?
as i understand from your description the following :
1.the overall number of handovers in all causes have decreased.
2.the handover percentage per cause is the same before and after for example PBGT handover is 95 % before and after swap
3.the power and all handover parameters have been mapped correctly.



the logical reason for handover number decrease is that u have harder handover decision than before . the causes of situation like this could be longer panelty time after successful or failed HO attempts , different P/N criteria settings.
also as u mentioned Siemens BTS differs from Huawei BTS in the issue of who decide when to trigger a handover:
Siemens:
BTS decide when to trigger HO but BSC choose which candidate is the best
Huawei:
BSC do the whole job

so this could mean that Huawei Handover Algorithm are little delayed than Siemens in taking the decision

[kyokuman]

Hi,

Yes I totally agree.
Thanks.

Hope this topic help others.

[justdream]

Dear Friend,

Could you please share your Siemens Huawei parameters mapping?

[melkaiy]

check the events sirs.... and trace the signalling info. most of the ho fails are due to incorrect configurations.