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Optimal
2011-09-26, 04:49 PM
Hi all,

In Huawei network, TCH drop increase from 1 % to 2% after cut 5 MHz from 2G, we already try to optimize BCCH & TCH frequency but the drop not improve so much. Can anyone recommend the parameters or/and features that will improve drop in overall network for this case ???

zlobster
2011-09-26, 05:13 PM
Hehe, wadda you expect? Improvement of DCR? Dude, u slashed 5MHz (count in terms of 200kHz ARFCNs)...:D Been there, seen it!

Anyway, here are some tricks for improvement: use SFH with max possible number of ARFCNs and take care of proper MAIO allocations, use AMR FR, carefully plan your BCCH, pray! This should improve the KPI but the overall customer experience may get worse because of AMR (robo-voice, etc.)

Optimal
2011-09-26, 05:55 PM
Hi zlobster,

Thank you for your suggestion.
I have some more questions. AMR FR is recommended, it means no need to activate AMR feature ???
And if I cannot change BB to SFH, what is the different way to improve DCR ???
In our netwrok we have E******* & Huawei, after refram it has no effect in E******* but critical effect in Huawei.

maverrickforever
2011-09-26, 07:24 PM
Implementing AMR FR is a good idea but you will also need to redo your frequency plan besides doing a full parameter audit of your database. WOuld also recommend trying to improve your FH planning.

Pray ! yes that is the best ********. God Bless :L

zlobster
2011-09-26, 08:26 PM
Implementing AMR FR is a good idea but you will also need to redo your frequency plan besides doing a full parameter audit of your database. WOuld also recommend trying to improve your FH planning.

Pray ! yes that is the best ********. God Bless :L Amen! :p


Hi zlobster,

Thank you for your suggestion.
I have some more questions. AMR FR is recommended, it means no need to activate AMR feature ???
And if I cannot change BB to SFH, what is the different way to improve DCR ???
In our netwrok we have E******* & Huawei, after refram it has no effect in E******* but critical effect in Huawei. It means you have to activate/unlock/enable the feature as per your vendor documentation. Alas, I don't have the specific H/// know-how yet.
Did you do a complete audit/consistency check of all definitions and parameters in your database/BSC/MSC, i.e. NBs, algos, etc.? Either way, I'd recommend you do it again.
If this doesn't help you don't have much left to do. Try to see the root cause of the dropped calls. See if the total DCR is not increased by only few contributing cells. See for RF conflicts on the border area (if any). Also, check to see if some of the refarmed spetcrum is not actually occupying the GSM one.
And the most universal solution there is - set radiolink timeout to MAX. :D
Try these and we'll talk again.

maverrickforever
2011-09-27, 12:30 AM
Amen! :p

It means you have to activate/unlock/enable the feature as per your vendor documentation. Alas, I don't have the specific H/// know-how yet.
Did you do a complete audit/consistency check of all definitions and parameters in your database/BSC/MSC, i.e. NBs, algos, etc.? Either way, I'd recommend you do it again.
If this doesn't help you don't have much left to do. Try to see the root cause of the dropped calls. See if the total DCR is not increased by only few contributing cells. See for RF conflicts on the border area (if any). Also, check to see if some of the refarmed spetcrum is not actually occupying the GSM one.
And the most universal solution there is - set radiolink timeout to MAX. :D
Try these and we'll talk again.


You can also try to play with the parameter RX_LEVEL_MIN_CELL. try increasing the value. There will be fewer drops but thee overall user experience will be a bit degraded due to prolonged calls in spite of bad quality.

hope you can find something similar in your system. The one i discussed here is for the Nokia systems.

Optimal
2011-09-27, 03:19 AM
I have some interested feature that might be improve this, Could
anyone have experienced on list of feature below please share to me.

- DRX

- Interference Based Channel Allocation

- Interference Rejection Combining

- Handover Re-Establishment

- Robust Air Interface Signaling

tremalnike
2011-09-27, 03:57 AM
* DL Power control is mandatory
* Use some features like repeated SACCH
* Icrease RLT value - actualy , this not solve problem - only hide it

And take care on adjacent channel interference - > so where have neighbor cell with adjacent ARFCN to current cell BCCH ARFCN- put it to TCH, in order to benefit from power control. Also put more downtilt or power reduction to high overshooting cells.

zlobster
2011-09-27, 05:17 AM
I have some interested feature that might be improve this, Could
anyone have experienced on list of feature below please share to me.

- DRX

- Interference Based Channel Allocation

- Interference Rejection Combining

- Handover Re-Establishment

- Robust Air Interface Signaling

In order to heal something you have to put the right diagnose first. Try to pinpoint the real root cause for the increased DCR. Since you are showing a plot for a cluster/BSC/GERAN (maybe?) it could be the case where 4-5 cells have enormous drop, thus affecting the whole picture. IMHO, that's mandatory. Otherwise, you'd be just masking the problem and this my friend will take its toll someday. With the interest along...

The rest of the features are just make-up. If you choose to allocate on clean channels only and you have a pretty interfered air interface, you'll just end up with blocking, for example. Try to avoid DRX, use only DTX if available. It wrecks more havoc than it helps. IMHO again.


*
* Icrease RLT value - actualy , this not solve problem - only hide it


I know, I just thought the fat smile at the end will suggest the (harsh) humor (sarcasm?).

You have all the weapons you need. Now stand up and fight.

Oh, and one last thing. As the second paragraph of my signature suggests - There's no such thing as a 'dropped call'. There's only 'handover-to-idle'.

Got it?;)

Optimal
2011-09-27, 01:19 PM
Could you give me the reason advangetage/ dsiadvancetage for DRX, KPIs impact for DRX activation?



In order to heal something you have to put the right diagnose first. Try to pinpoint the real root cause for the increased DCR. Since you are showing a plot for a cluster/BSC/GERAN (maybe?) it could be the case where 4-5 cells have enormous drop, thus affecting the whole picture. IMHO, that's mandatory. Otherwise, you'd be just masking the problem and this my friend will take its toll someday. With the interest along...

The rest of the features are just make-up. If you choose to allocate on clean channels only and you have a pretty interfered air interface, you'll just end up with blocking, for example. Try to avoid DRX, use only DTX if available. It wrecks more havoc than it helps. IMHO again.



I know, I just thought the fat smile at the end will suggest the (harsh) humor (sarcasm?).

You have all the weapons you need. Now stand up and fight.

Oh, and one last thing. As the second paragraph of my signature suggests - There's no such thing as a 'dropped call'. There's only 'handover-to-idle'.

Got it?;)

bdplanner
2011-09-27, 01:39 PM
For a long Run consider buying and AFP tool such as optimi xafp . Our manager bought this and we had good result after implementation

veasna
2011-09-27, 03:12 PM
Hi Optimal,
As my point of view for your problem is due to interference after your network was cut 5MHz , so the solution for this the frequency planning should be taken into account by using planning tool.

Br,
veasna

zlobster
2011-09-27, 04:13 PM
Could you give me the reason advangetage/ dsiadvancetage for DRX, KPIs impact for DRX activation?

Well, if we are talking about DRX for CS paginig, it's perfectly fine. And it does save battey life in the UEs. As for the disadvantages, it's a bit long for me to discuss here, and also I don't have hard facts to support my beliefs.

And again, it may sound a bit harsh, but I think you are searching for the magic wand. With one wave and the DCR goes back to normal. Nah... :( If there were such a wand, I wouldn't be doing what I do now. It'd just be not interesting for me. It's the deep digging and the satisfaction after you find the problem and solve it.

justdream
2012-02-08, 04:19 AM
I have some interested feature that might be improve this, Could
anyone have experienced on list of feature below please share to me.

- DRX

- Interference Based Channel Allocation

- Interference Rejection Combining

- Handover Re-Establishment

- Robust Air Interface Signaling

Dear Optimal,

Could you please give us of your time and share more information (description)
about above mentioned points [DRX, Interference Based Channel Allocation, Interference Rejection Combining, Handover Re-Establishment, Robust Air Interface Signaling]

Many Thanks