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magno22
2012-07-17, 05:47 PM
Dears,

how to increase cell HSPA capacity changing schedule? Now we use 15 code cell each cell. UE TTI is chosen by dynamic(2ms and 10ms). If i configure only 2ms TTI coverage will be down. How to increase HSDPA capacity?

chefo
2012-07-17, 07:25 PM
are you sure about the tti? how can you configure 10ms tti for hsdpa?

magno22
2012-07-18, 09:14 AM
are you sure about the tti? how can you configure 10ms tti for hsdpa?

Sorry it was HSUPA TTI. :D

chefo
2012-07-18, 02:01 PM
So, I understand your question is how to improve the hsdpa performance in terms of capacity.

There are two main targets here - cell throughput and user throughput. You have to first define your strategy. As you can guess there are tradeoffs - you could either increase cell throughput and sacrifice user experience for the users with worse radio conditions using Best CQI or Proportional Fair-Low scheduler, or you can improve user throughput for the mentioned users through using Proportional Fair-Medium or High. I would not recommend using Round Robin.

Of course above all I assume you have no Iub transmission capacity issues or anything else that could limit the nodeb throughput apart from the radio interface.

You could never see 15 codes in use unless your cell is dedicated only for hsdpa. The maximum you could get for hsdpa when there is any R99 traffic with reasonable admission limits is 14 codes. Activating 64QAM and MIMO can increase the hsdpa throughputs - both cell and user.

As for HSUPA, you should consider that this service uses UL CE, and it is quite hungry for it - if you have any UL congestion issues - CE or UL RSSI - consider disabling the 2ms TTI for HSUPA, also you could play with admission limits for number of simultaneously active HSUPA users.

Regards!

Chefo.

deknoi55
2012-07-19, 01:14 AM
I think same with chefo (R99 will get TTI=10 or not ?)
If you set 15 code it's must effect to your site . another resource R99 maybe unavialable .
If you wanna improve you may get CQI(28-30) 16QAM or max 64QAM.
Try to Up CPICH more . I think you will get more Value.