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boring
2010-07-11, 01:53 AM
hi guys

need to build my reputation quickly to become a member so if you have any question related on HSPA technology please post it here!

of course, anything related to packet end-to-end optimisation will be applicable here as well!

your thanks and rep will be highly appreciated

thanks in advance

kais
2010-07-11, 02:12 AM
can u give a HSPA data optimization guide :p


hi guys

need to build my reputation quickly to become a member so if you have any question related on HSPA technology please post it here!

of course, anything related to packet end-to-end optimisation will be applicable here as well!

your thanks and rep will be highly appreciated

thanks in advance

xkamikaz
2010-07-11, 02:18 AM
Yeah If there any doc about KPI and Practical Optimization to share and thanks ;)

arefo1o
2010-07-11, 02:32 AM
please share HSPA optimization guide :)

boring
2010-07-11, 03:45 AM
so by popular request this is a very practical step-by-step optim guide of HSPA using Actix.

http://rapidshare.com/files/406184547/HSDPA_Optimization.pdf

thanks and rep please!

Blacktiger
2010-07-11, 04:29 AM
so by popular request this is a very practical step-by-step optim guide of HSPA using Actix.

http://rapidshare.com/files/406184547/HSDPA_Optimization.pdf

thanks and rep please!

Good One.....Keep it UP>>

arefo1o
2010-07-11, 04:34 AM
so by popular request this is a very practical step-by-step optim guide of HSPA using Actix.

http://rapidshare.com/files/406184547/HSDPA_Optimization.pdf

thanks and rep please!


great document for HSDPA optimization using actix ..... :)

Rooster[BG]
2010-07-11, 05:39 AM
It sounds very nice. Can you re upload or upload to 4shared.com (only 10 downloads for non premium accounts in rapidshare)


so by popular request this is a very practical step-by-step optim guide of HSPA using Actix.

http://rapidshare.com/files/406184547/HSDPA_Optimization.pdf

thanks and rep please!

hendral
2010-07-11, 08:43 AM
Pls reupload to www.4shared.com

cococrunch
2010-07-11, 12:02 PM
hi guys

need to build my reputation quickly to become a member so if you have any question related on HSPA technology please post it here!

of course, anything related to packet end-to-end optimisation will be applicable here as well!

your thanks and rep will be highly appreciated

thanks in advance

Hi Friend,

I noticed there are more "HSDPA accessibility failures due to UE" in second/third carrier. Do you have the same experiences? What can you recommend to optimize this?..
Im currently working with NSN vendor. Thanks.. :)

kevin_h811
2010-07-11, 12:39 PM
appreciate if shared at 4SHARED..thanks

regards///

boring
2010-07-11, 02:45 PM
new download link through 4shared


http://www.4shared.com/document/CjxpBpXX/HSDPA_Optimization.html

thanks

boring
2010-07-11, 02:50 PM
Hi Friend,

I noticed there are more "HSDPA accessibility failures due to UE" in second/third carrier. Do you have the same experiences? What can you recommend to optimize this?..
Im currently working with NSN vendor. Thanks.. :)

I'm afraid i have seen these type of failures.

however, i suspect if there is some kind inter-frequence cell reselection/handover issue which generates this problem.

cocoloco
2010-07-12, 04:17 PM
Hi expert,

Do you know how CQI calculatation is made in UE? Thanks

senjamir
2010-07-12, 04:58 PM
Hi expert,

Do you know how CQI calculatation is made in UE? Thanks


The CQI value that the terminal reports is a function of multipath environment, terminal receiver type, ratio of the interference
of the own base station compared with others and expected BTS HSDPA
power availability. Therefore the value does not correspond to the SIR that the terminal is experiencing. It is reporting the under the current radio conditions.

So mathematically CQI calculation can be expressed as,

CQI = Time Varying Total Total Transmit power (including the offset set in the RNC) + other cell Interference +radio channel quality + thermal noise

The reported CQI also have added offset because the HS DSCH transmit power to the user might be different by the assumed power by the UE.

i hope this might help you. :)

Br,

Sen

boring
2010-07-13, 03:22 AM
Hi expert,

Do you know how CQI calculatation is made in UE? Thanks



Strictly speaking, CQI is not a measurement of radio conditions, however we (radio engineers) use it as a proxy of the radio conditions experienced by the UE.

3GPP defines CQI as: The maximum transport block size (i.e. L1 data rate) which according to the current radio conditions (RSCP, SIR) will result in a BLER of 10%.

So what actually happens: UE performs RSCP and Pilot SIR measurements, it reads the gamma (measurement power offset) parameter and according to its HSDPA category (see delta parameter), it decides what should be the maximum block size and hence the corresponding CQI. Note: this decision is not standardised but a black box for every UE vendor.

Nonetheless, we use CQI to appreciate radio conditions. and thus if CQI > 20 we say radio is excellent whereas if CQI < 10 then we say radio is bad. We must be always very careful with such statements because CQIs are affected by the gamma parameter. this means that you can measure same RSCP, pilot SIR for two cells but the first has CQI=20 and the second CQI=12 and the difference comes purely because of an 8-dB difference of the gamma param.

hope this helps

cocoloco
2010-07-13, 04:47 PM
Dear Boring,

Where can i see the gamma param for each call?

wolverine
2010-07-13, 06:11 PM
Dear Boring,

Where can i see the gamma param for each call?

This is sent to the UE as part of the Radio Bearer Setup process.

rosan
2010-07-13, 06:14 PM
Dear Friend,
Can u elaborate more about the gamma parameter?

Thanks

boring
2010-07-14, 01:04 AM
Dear Friend,
Can u elaborate more about the gamma parameter?

Thanks

The idea behind the gamma parameter (3GPP view) is to show how much power is available for HSDPA with respect to the pilot power. so if pilot = 33 dBm and gamma = 6 dB, then this means that the maximum available power for HSDPA is 39 dBm.

Vendor implementation however allows for usage of all available DL Tx power up to 100%, so this means that the "original definition" of the gamma is not really apllicable. Nonetheless, the gamma parameter is used by the Node-B to calculate a reference level based on which all HSDPA transmissions take place. For this reason for parameter optimisation point of view it is important to have a gamma parameter such that the reported CQIs are distributed across mainly the range between 10 to 30. otherwise, total HSDPA cell throughput may not optimum.

BR

cocoloco
2010-07-15, 07:28 PM
This is sent to the UE as part of the Radio Bearer Setup process.

Sorry but i don´t have a big knowledge about this. It could be "measurementPowerOffset"?. I´ve found it in RB Setup message with value 15.

Thanks very much

boring
2010-07-15, 09:26 PM
Sorry but i don´t have a big knowledge about this. It could be "measurementPowerOffset"?. I´ve found it in RB Setup message with value 15.

Thanks very much

correct. gamma is the measurement power offset. value of 15 means actually 7.5 dB

BR

tpkj
2010-07-16, 10:29 PM
correct. gamma is the measurement power offset. value of 15 means actually 7.5 dB

BR

Thank you for information Guys. I have found it in RRC message.
So it indicates an positive or negative offset of the HS-PDSCH power compared to the received CPICH power. the range is from -6 to ??? (I have found 13) with the step 0.5 dB.

boring
2010-07-17, 01:02 AM
Thank you for information Guys. I have found it in RRC message.
So it indicates an positive or negative offset of the HS-PDSCH power compared to the received CPICH power. the range is from -6 to ??? (I have found 13) with the step 0.5 dB.

19 or (9.5 dB) is the maximum i have seen

manson
2010-07-20, 01:07 AM
19 or (9.5 dB) is the maximum i have seen

Plz... share for PS optimization guide...

tpkj
2010-07-31, 06:30 AM
This is document about CQI calculation. Maybe it will be usefull for you.
Reputation and thanks is welcome.:)

salamanda1969
2010-10-25, 07:30 PM
Hello Cococrunch,

We also experience large HSDPA failures due to UE. Have not found the root cause, but a reset work in most cases.

Whoever finds it first, share it on the forum.

Cheers.