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parsarka
2010-06-14, 06:39 PM
Hi Experts,
I am facing terrible problem in DL throughput in EDGE/GPRS while moving in car.My PDP gets activated & after that most of the time the DL throuhput remains 0kbps.Please suggest urgently which all parameters I should change to resolve this issue in Huawei system.
BR
Raj

parsarka
2010-06-15, 05:31 PM
Experts,request you to please suggest me a solution to this problem as its very urgent :(

RF engineer
2010-06-16, 02:52 AM
Hi Experts,
I am facing terrible problem in DL throughput in EDGE/GPRS while moving in car.My PDP gets activated & after that most of the time the DL throuhput remains 0kbps.Please suggest urgently which all parameters I should change to resolve this issue in Huawei system.
BR
Raj
did you do drive test during stationary if you have still problem or not.
BR
RF

nevy_14
2010-06-16, 04:45 AM
did you do drive test during stationary if you have still problem or not.
BR
RF

agree...and maybe you should try to conduct ping test and see if the test is successful.

BR,
nevy_14

parsarka
2010-06-17, 07:57 PM
Hi,
I have done the ping test & seen that the RTT is high,around 1200ms.The throuhput is better in static & poor while moving.Any parameter suggestions???

RF engineer
2010-06-17, 09:43 PM
Hi,
I have done the ping test & seen that the RTT is high,around 1200ms.The throuhput is better in static & poor while moving.Any parameter suggestions???
Of course you have less throughput in moving because every time when you make cell reselection you loss your TBF connection and again re-established , there is feature that makes TBF released delay. check and activated it will improve if you have huawei i can tell you. and long RTT is also the same reason but one thing you can ask what is the TCP configuration .
BR
RF

mrdiamond
2010-06-18, 05:45 AM
and the final???

nevy_14
2010-06-18, 02:04 PM
Hi,
I have done the ping test & seen that the RTT is high,around 1200ms.The throuhput is better in static & poor while moving.Any parameter suggestions???

you can check if your test is at the edge of the cell, because bad radio condition (low signal level or interference) mainly affected GPRS/EDGE throughput (CMIIW).if it does than you can refer to RF Engineer suggestion regarding the TBF release delay...

BR,
nevy_14

josogun2
2010-06-18, 05:44 PM
are you downloading from FTP server or http address?
if it http, try another add,
you can also check your serving cell at that point if it is configure for data.

beniy
2010-06-18, 06:45 PM
Hi Experts,
I am facing terrible problem in DL throughput in EDGE/GPRS while moving in car.My PDP gets activated & after that most of the time the DL throuhput remains 0kbps.Please suggest urgently which all parameters I should change to resolve this issue in Huawei system.
BR
Raj
Dear,
Let me know in how many cells you have this problem?
For one cell? one site? or one BSC? or one region?
There are so many counters (Timers) to solve this one!!!
Let me know just in upload or download??

beniy
2010-06-18, 07:08 PM
Hi Experts,
I am facing terrible problem in DL throughput in EDGE/GPRS while moving in car.My PDP gets activated & after that most of the time the DL throuhput remains 0kbps.Please suggest urgently which all parameters I should change to resolve this issue in Huawei system.
BR
Raj

And if you have any urgent or any question please ask in below post!!
because I always check that and update you!!!
http://www.finetopix.com/showthread.php?t=9094

Thanks

parsarka
2010-06-19, 01:15 AM
Of course you have less throughput in moving because every time when you make cell reselection you loss your TBF connection and again re-established , there is feature that makes TBF released delay. check and activated it will improve if you have huawei i can tell you. and long RTT is also the same reason but one thing you can ask what is the TCP configuration .
BR
RF

Thanks...Yes I have Huawei system..please suggest parameter changes both for improvement of this poor throughput & RTT(Reputations added :) )

parsarka
2010-06-19, 01:17 AM
are you downloading from FTP server or http address?
if it http, try another add,
you can also check your serving cell at that point if it is configure for data.

I am using FTP address

RF engineer
2010-06-19, 02:33 AM
Thanks...Yes I have Huawei system..please suggest parameter changes both for improvement of this poor throughput & RTT(Reputations added :) )
There is parameter in GPRS attribute window-PS network optimization parameters- increase parameter(release delay of downlink TBF(ms)).
But before doing this try to limit the coverage of each cell so that to reduce ping pong effect.
BR
RF

beniy
2010-06-19, 11:21 PM
Thanks...Yes I have Huawei system..please suggest parameter changes both for improvement of this poor throughput & RTT(Reputations added :) )

You should chech these parameters:

1)T3192
2)
Release Delay of Downlink TBF(ms)


1)
This parameter specifies the timer set for the MS to wait for the TBF release after receiving the last data block.
When the MS receives the last RLC data block carrying the last block flag (FBI=1) and confirms that all the RLC data blocks on the TBF are received, the MS sends the Packet Downlink Ack/Nack message carrying the final acknowledgement flag (FAI=1) and starts T3192 at the same time.
If T3192 expires, the MS releases the TBF resources and monitors paging channels. During the TBF release process, if the MS is in half-duplex mode and receives the Packet Uplink Assignment message, the MS responds immediately.
If the MS does not receive the Packet Uplink Assignment message during the TBF release process, the MS enters the packet idle mode. If the MS is in dual transfer mode, it enters the dedicated mode.


2)

This parameter specifies the release delay of the downlink TBF.
After sending the last downlink RLC data block and confirming that all downlink data blocks are received, the network does not immediately notify the MS of releasing this TBF but forcedly set the last data block not received. Therefore, keep this TBF unreleased by continuously resending the last downlink data block with the Relative Reserved Block Period (RRBP) flag. During the release delay of a downlink TBF, as long as the upper layer of the network has a requirement of downlink data transmission, the extracted downlink RLC blocks can be sent on this downlink TBF. At the same time, the status of the downlink TBF changes from release delay to downlink transmission. In addition, during the release delay, the MS must send the Packet Downlink Ack/Nack message on the uplink data block corresponding to the RRBP to maintain the communication with the network. Therefore, when the MS needs to send the uplink data, it can send an uplink request through Channel Request Description carried in the Packet Downlink Ack/Nack message.
The value 0 specifies that release delay function of the downlink TBF is disabled