Channel switching between FACH and DCH

[linhhy]

dear all,

In 3G Huawei system, I saw that for increasing throughput for UE in case of switching from FACH to DCH, RNC needs Event 4a reported from the UE, and the system also needs Event 4b for downswitch from DCH to FACH.
In my opinion, for UL switching, it's OK, but for DL switching it's not perfect, because RNC is already know buffer size for that UE in RLC buffer (like E******* system).
any expert can help me to clear this issue?

[agenov]

For DL the RNC doesnt need 4b from UE so to order transition DCH->FACH


dear all,

In 3G Huawei system, I saw that for increasing throughput for UE in case of switching from FACH to DCH, RNC needs Event 4a reported from the UE, and the system also needs Event 4b for downswitch from DCH to FACH.
In my opinion, for UL switching, it's OK, but for DL switching it's not perfect, because RNC is already know buffer size for that UE in RLC buffer (like E******* system).
any expert can help me to clear this issue?

[linhhy]

Hi Agenov,

The attract from Huawei DCCC:
"The prerequisites for DL rate adjustm ent based on traffic volume are as follows:
• I f the function o f DL rate adjustm ent based on link quality is enabled, the DL power must be very strong, which can be determ ined according to event F.
• The cell is not in the basic congestion state in the DL. I f the cell is in the basic
congestion state in the UL, only the service rate lower than the G BR can be increased to the GBR.
After receiving a report on event 4b, the RNC triggers rate decrease. After receiving a report on event 4a, the RNC triggers rate increase."

Do you have any Huawei document to talk the RNC doesnt need 4b from UE so to order transition DCH->FACH in DL?

[agenov]

HI,

What u pasted is for DCCC algorithm that controls rate UP/Down for R99. Transition between different RRC states and specifically DCH to FACH doesnt need 4b from the UE because the RLC buffer is in the RNC , just like you said initially.

br
alex


Hi Agenov,

The attract from Huawei DCCC:
"The prerequisites for DL rate adjustm ent based on traffic volume are as follows:
• I f the function o f DL rate adjustm ent based on link quality is enabled, the DL power must be very strong, which can be determ ined according to event F.
• The cell is not in the basic congestion state in the DL. I f the cell is in the basic
congestion state in the UL, only the service rate lower than the G BR can be increased to the GBR.
After receiving a report on event 4b, the RNC triggers rate decrease. After receiving a report on event 4a, the RNC triggers rate increase."

Do you have any Huawei document to talk the RNC doesnt need 4b from UE so to order transition DCH->FACH in DL?

[linhhy]

I just found a document talk that RNC (huawei) also called internally event 4a when traffic volume (in RNC RLC buffer) is higher than threshold.

[tpkj]

I just found a document talk that RNC (huawei) also called internally event 4a when traffic volume (in RNC RLC buffer) is higher than threshold.

Please, could you upload that document?