numHsScchCodes 1 or 3 Which is better? E///

[RFDude_PMA]

Hi all Gurus

E******* P7

I have a question regarding the use of more that one hsScchcodes with the feature Dynamic Allocation of codes and scheduler active in the node:

If i use 3 insted of one?

Thanks

[TechCrunch]

Basically if you use 3, then you are able to multiplex 3 simultaneous HSDPA users in each TTI.

[kyokuman]

Generally 1 is used in networks with low number of users, so that they can get the highest peak throughput...

Once network has many users, it is better to decrease their peak rate, but schedule them faster.

I think most of networks use 3.

However, if any can share experience using 4, I am very interested !

[RFDude_PMA]

Hi Kyokuman

I had set a Node, in one sector with this parameter in thee and the other two sectors in one. The DT team advice me that the throughput where in 600k at 100m from the cell, only two connection in hsdpa at the time. Then I change the setting to three. He stop the connection and start a new one (switch off and on the mobile). Then after that he got speeds up to 2.8m.

In the documentation I have "Alex Ran P7" it only indicates tti 2ms, we have tti 10ms. But it works..

Now I did apply this in the whole network..

I wanted to share this with you guys..

[TechCrunch]

Can you share what type of scheduler are you using ? Also what 3gpp release equipment are you using ?

From my understanding, HSDPA should always be scheduled with 2ms TTI?

[RFDude_PMA]

Hi all

Equipment is E******* p7
The scheduler I prefer is Proportional medium fair.

[salahb]

Yes Of course HSDPA always used scheduled with 2ms TTI

[TechCrunch]

Hi Kyokuman

I had set a Node, in one sector with this parameter in thee and the other two sectors in one. The DT team advice me that the throughput where in 600k at 100m from the cell, only two connection in hsdpa at the time. Then I change the setting to three. He stop the connection and start a new one (switch off and on the mobile). Then after that he got speeds up to 2.8m.

In the documentation I have "Alex Ran P7" it only indicates tti 2ms, we have tti 10ms. But it works..

Now I did apply this in the whole network..

I wanted to share this with you guys..

Can you make this clearer.
1 cell with MaxHSSCCH = 3 , and another with MaxHSSCCH = 1 . Where was the DT carried out , ie in which cell ?

In case the DT was carried out in the cell with MaxHSSCCH = 1 and there were 2 HSDPA users simulataneously then definately there will be impact to tp since only 1 HSDPA user can be schedules per TTI.

[TechCrunch]

Hi all

Equipment is E******* p7
The scheduler I prefer is Proportional medium fair.

It good that you are using a proportional fair scheduler, are u using a cell specific or Node B specific scheduler ?

[gprastomo]

Hi,

Actually it will be depends on the HSPDSCH Code that you use, if you use 5 codes, its better to put 1-2 HSSCCH COde.
If you have 10 PDSCH its better to put 3 or 4. But if you have 15 codes its better to put 2 HSSCCH Codes/

SInce HSSCCH Codes will occupy the Chanelization codes so to achieve 15 codes, you need to put max 2 HSSCCH Code.

br



Hi all Gurus

E******* P7

I have a question regarding the use of more that one hsScchcodes with the feature Dynamic Allocation of codes and scheduler active in the node:

If i use 3 insted of one?

Thanks

[RFDude_PMA]

Hi gprastomo

This is a good intel, thanks.

But just to understand the concept, HSSCCH Codes increase the capacity of users to use HS codes and throughput increase but also use DL channalization codes so it will reduce R99 connection capacity , Is this correct?

Thanks again.. my reps to you..

BRGDS

[gprastomo]

Hi My friend,

Actually HSSCCH Codes, will work as code multiplexing, let say we have 1 hs scch code, so in 1 TTI, 1 user will be allocated to these TTI, then if we have 3 HSSCCH Code, so in 1 TTI, 3 users can be alocated instead of waiting to the next TTI etc, so its good for user perception.

The thing that we need to consider is, this HSSCCH Code will consume Chanelization Code of SF 128, let say we have 4 HS SCCH Code with SF 128, so it will blocked 2 codes of SF 64, and 1 code SF 32, or 1 code SF 16.
1. So with 4 HSSCCH Code, it consume 1 Code SF 16.
2. For Common Channel and Signalling etc already consume 1 Code SF 16

So totally for HSSCCH Code and Common Channel, will occupy 2 Codes of SF 16. so thats why with 3 or 4 HSSCCH Codes, you will not be able to achieve 15 Codes PDSCH, maximum only 14 codes.
Then if you have HSUPA, it will increase the Code Occupancy as well.

br



Hi gprastomo

This is a good intel, thanks.

But just to understand the concept, HSSCCH Codes increase the capacity of users to use HS codes and throughput increase but also use DL channalization codes so it will reduce R99 connection capacity , Is this correct?

Thanks again.. my reps to you..

BRGDS

[linhhy]

Hi all Gurus

E******* P7

I have a question regarding the use of more that one hsScchcodes with the feature Dynamic Allocation of codes and scheduler active in the node:

If i use 3 insted of one?

Thanks

Hi,

In my opinion, I cant tell you which one is better, because it base on some input factor from your network.

Basically, number hsScchcodes means how many User can be scheduled in one TTI. more hsScchcodes means more user can be scheduled on 1 TTI, also spend more code (1 HC-SCCH is corresponding 1 SF 128), more power for HS-SCCH (need to take care).

If your network have maximum 5 HS-DSCH codes, almost USB user, then I think 1 SC SCCH is the best one; if almost users are mobile, I think 2 SC-SCCH is good.

If your network have more than 5 HS-DSCH code, what is typical UE class in your network? If almost UEs support 5 codes, 2 HS-SCCH is the best one with maximum 10 codes HS-DSCH; 3 HS-SCCH is the best one with maximum 15 codes HS-DSCH.

hopefully it is useful :D

[TechCrunch]

Hi ,

I think usage of 3 HS-SCCH codes is always better in terms of improved spectral efficiency especially in the case of high number of simultaneous users, PF scheduler and NodeB Specific scheduler.

In almost all HSPA networks I've worked in there is no limitation of 5 codes for HSDPA (unless from commercial point of view) It is common to have 15 codes enabled for HSDPA or a max of 10 codes .. As such 3 codes are beneficial otherwise it would be a wastage of HSPDSCH codes. In rel7, HS_SCCH can be set to 4 , and here there seems to be alot of discussion to use 3 or 4 HSDPA call per TTI.

[dk2000]

You must monitor the cell throughput and choose the optimization value.

In my network, when we change this parameter from 2 to 3, the cell throughput is increased. So I think 3 is the optimization value.:lol

Another way, I must calculate the distribution of UE.

[zee86]

Hi all Gurus

E******* P7

I have a question regarding the use of more that one hsScchcodes with the feature Dynamic Allocation of codes and scheduler active in the node:

If i use 3 insted of one?

Thanks

if you use one it wil increase the user througput and decrease the cell througput if i am not rong

[boring]

hi,

it makes sense to have more than 1 HSSCCH codes only when you deploy more than 5 HSDSCH codes (e.g. 10 and up to 15)

actually, for large deployments (e.g. 15), it is imperative to deploy 3 or even 4 codes.

you should always remember that the more the codes (3 or 4) the more the users can be scheduled in the same TTI which means that the average CELL THROUGHPUT will be higher in most typical scenarios

finally, because of the increasing presense of smart-phones which are typically always-on connected, it is better to have 4 HSSCCH codes and thus some of these codes will be used by them to just connect to the internet for example to simply check if there are incoming e-mails/messages/etc, whereas the rest will be always available for actual downloads (i.e. high throughput connections)

hope this helps

[urspali2000@gmail.com]

By using 3 u can u more users but this would decrease ur user throughput

[RFDude_PMA]

No dude

It will increase it.. I had prove it. Subscriber experience also is better.