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faisaladeem
2015-02-19, 06:04 PM
Hi,

Anyone has done any trial to disable compressed mode during HS ? H// normally keeps it on while E// keeps it off. It might improve cell edge HS drop rate, any practical trial results will be helpful.

Thanks,
Faisal

fahmi
2015-02-21, 01:46 AM
I think activating HSPA CM will reduce PS drop on R99. In an emergency situation, there is no enough time to convert from HS to DCH and start CM so UE drops on R99 !

faisaladeem
2015-02-22, 08:45 PM
@ Fahmi, R99 has SHO gain and more power headroom so theoretically it can sustain poor RF. However this is all subjective, that's why I was looking for trial results if anyone has done it somewhere.

shishio
2015-02-23, 10:14 PM
Hi,

Anyone has done any trial to disable compressed mode during HS ? H// normally keeps it on while E// keeps it off. It might improve cell edge HS drop rate, any practical trial results will be helpful.

Thanks,
Faisal

i dont think this is a good idea, disabling compressed mode means the RNC will not be able to have accurate measurements of the serving cells neighbors and this could cause HO to bad neighbors thereby increasing your drop rate. if you are worried about an emergency situation, there isnt enough time to convert from HS to DCH to start CM, then you can trigger CM earlier in the cell by adjusting the 2D/2F parameters so as to cause quicker HO to 2G and prevent a drop.

Lazaros
2015-03-01, 09:08 PM
I also don't agree. HSDPA CM in Huawei is used for many years. The only problem is that it introduces many inactive TTI, meaning that (depending on the HSDPA throughput formula) HSDPA throughput goes down. In case you deactivate it, users will switch to R99 DL, which also gives many side problems. A normal practice is to full deactivate 3G to 2G Handover for PS, so that there will be no CM at all