CE utilisation

[ahmadruslani]

Andoni,

My DL CE utilization is lower compare to UL CE. I notice that my node will used up more CE when there are multiple concurrent HSUPA users.

[shishio]

Hello experts,

can anyone explain to me the relationship between number of channel elements (CE) and walsh codes in a cdma system?

[andoniwireless]

Andoni,

My DL CE utilization is lower compare to UL CE. I notice that my node will used up more CE when there are multiple concurrent HSUPA users.

Of course @ ahmadruslani you always will more CE DL used because the congestion will be in the uplink.. Why is the question..?? The aswer is because all your users that are downloading on R99&HSDPA is Uplonding in R99 using CE UL.. but you will have a litle reduce of this CE when you have most of the users on HSUPA.

You can try making some change of the licence kit of the CE from the DL to the UL.

If you are using Huawei with BBU3800 you need to make a CE expansion, because when you active the HSUPA services in it model the BBU reserved 64 CE for default.

Regards.

Andoni

[andoniwireless]

Hello experts,

can anyone explain to me the relationship between number of channel elements (CE) and walsh codes in a cdma system?

****


Channel Elements
Better services more CE used...

Walsh Codes.. better services SF lower.

Regards

Andonni

[boring]

Hi

UL CE consumption is much higher than DL mainly because of HSDPA (which has fixed CE consumption). effectivelly, with a fixed number of CEs multiple UEs can be served but its UE requires its own CE for the uplink (either R99 or HSUPA)

the mapping between CE and SF are as follows:

SF64 --> 1
SF32 --> 1
SF16 --> 2
SF8 --> 4
SF4 --> 8
2SF4 --> 16
2SF2 --> 32
2SF2+2SF4 --> 48

you should also bear in mind that soft handover makes the condition even worse for UL CE consumption.

HSDPA is not affected at all, whereas both R99 or HSUPA (depending what it used for the reverse channel) is affected by soft-handover overhead

hope this helps

[dodotiro]

Hi

UL CE consumption is much higher than DL mainly because of HSDPA (which has fixed CE consumption). effectivelly, with a fixed number of CEs multiple UEs can be served but its UE requires its own CE for the uplink (either R99 or HSUPA)

the mapping between CE and SF are as follows:


SF64 --> 1
SF32 --> 1
SF16 --> 2
SF8 --> 4
SF4 --> 8
2SF4 --> 16
2SF2 --> 32
2SF2+2SF4 --> 48

you should also bear in mind that soft handover makes the condition even worse for UL CE consumption.

HSDPA is not affected at all, whereas both R99 or HSUPA (depending what it used for the reverse channel) is affected by soft-handover overhead

hope this helps

adding some comparison between vendors

CE Comparison.jpg

[tester]

@dodotiro
Please share full PPT

[agenov]

i wouldn't believe it so easy. Dont trust what H// says in their presentations just like that. Test it or ask someone and then make a conclusion. if someone in the forum can provide personal test results for CE consumption between vendors then i can agree.

adding some comparison between vendors

CE Comparison.jpg

[kevin_h811]

Hi Boring,

Can you say that we could lessen congestion on UL CE if we downtilt the antenna?

I have this issue also, but based on drivetest, the site I'm mentioning is overshooting, could this possible contribution why I have congestion on UL CE and not on DL CE? This is not a fully utilized NodeB.

Regards//

[boring]

Hi Boring,

Can you say that we could lessen congestion on UL CE if we downtilt the antenna?

I have this issue also, but based on drivetest, the site I'm mentioning is overshooting, could this possible contribution why I have congestion on UL CE and not on DL CE? This is not a fully utilized NodeB.

Regards//

yeap. dowtilting an antenna especially for an overshooting cell always helps to reduce the congestion of UL CE

but be careful. as I said to a previous e-mail from the moment you activate HSUPA then always you become UL CE limited, because every UE has its own CE allocation in the uplink whereas HSDPA has a shared allocation in the dowlink