Huawei: SRB over HS and F-DPCH

**boring** · 2014-12-16, 03:11 PM

Hi,
do you have any experience of SRB over HSDPA, SRB over HSUPA and Fractional-DPCH?
i'm interested in knowing if there are any issues when activating these features in the live Huawei network.
many thanks in advance

**Finetopix** · 2014-12-16 03:11 PM

**rfsupp** · 2015-01-14, 02:21 PM

Until R14 there are some issues with this features, mainly about drop call. The fact to make worse the drop call isn't just related with lack of soft handover when SRB is mapped with HSPA channel.
Is more related with issues on layer 2, but Huawei has a functionality SRB H2D that helps your rentainability.

**senjamir** · 2015-01-14, 05:55 PM

Hi,

I tried doing SRB over HSUPA and it improve the PS DR. The CS DR was not affected. I made sure that during the radio resource allocation the RRC will not use SRB over HSUPA but the normal DCH channel. It will only use it during PS service. You can check the following parameters.
SrbChlType = HSUPA
SrbChlTypeRrcEffectFlag = FALSE.

I hope this help. (",)

Br,
Sen

**senjamir** · 2015-01-14, 05:56 PM

It is a Huawei Equipment by the way. (",) (

Originally Posted by senjamir

Hi,

I tried doing SRB over HSUPA and it improve the PS DR. The CS DR was not affected. I made sure that during the radio resource allocation the RRC will not use SRB over HSUPA but the normal DCH channel. It will only use it during PS service. You can check the following parameters.
SrbChlType = HSUPA
SrbChlTypeRrcEffectFlag = FALSE.

I hope this help. (",)

Br,
Sen

**rfsupp** · 2015-01-15, 12:23 AM

Hi Senjamir, you are missing something....When you define SrbChlTypeRrcEffectFlag, you are telling to the UE to activate SRB only during RB phase instead RRC phase.
And when you define SrbChlType = HSUPA, you are saying to the UE please activate SRB only over HSUPA for UL and keep the SRB over DCH for DL.

For the reason above you had luck to not degrade the DCR, that usually expected in R14. But from R16 the feature is much more stable.