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T_ADD
2011-10-25, 07:22 AM
Hi there cdma guys, does anyone have any experience having done 2 carriers for EVDO at a BTS?

Please verify the following information.

Can this be done?

EVDO Sector 0 (eg., only):

Carrier 1 = CH:201, PN:168 (eg., CH & PN)
Carrier 2 = CH:201, PN:372 (eg., CH & PN)

The above has same frequency but different PN. This means no hard hand-off but needs a spare usable PN.

Or is it only this can be done?

Carrier 1 = CH:201, PN:168 (eg., PN)
Carrier 2 = CH:242, PN:168 (eg., PN)

The above has different frequency but same PN. This means that hard hand-off will have to be used. And this is what I want to avoid. Should I or not?

I need some input guys.

dmitry28
2011-10-25, 08:07 AM
correct second version. The same frequency and different PN-offset will only interference

T_ADD
2011-10-25, 09:13 AM
No. I've done dual carrier networking on 1x where I've used CH:78 and CH:119 with the same PN but with no interference.

Synonymously, I need to confirm if same frequency but different PN can be used (No.2 scenario).

newyzy
2011-10-25, 11:58 AM
I see all equipment set PN in Sector level but not Sector,so you can't do "same frequency but different PN":p

T_ADD
2011-10-25, 02:11 PM
I see all equipment set PN in Sector level but not Sector

Hi newzy, please explain further on what you said. I need to understand before coming to any conclusion. :)

dimooon11
2011-10-25, 03:08 PM
you can't use the same frequency (no matter what PN) because this will lead to self-interference

what is wrong with hard hand-off? in case of continuous 2 carrier coverage you don't need HHO. HHO needed only for discontinuous coverage and in case of high traffic load

T_ADD
2011-10-25, 03:50 PM
Ok, understood but I still have to configure hand-off between the 2 different frequencies which will be HHO, right? That will have have to be done.

dimooon11
2011-10-25, 05:10 PM
yes you have. then you can check HHO related counters in NMS to check HHO attempts and success ratio. i'm not sure about 1x but in EVDO HHO rarely occur - it is usually hand-down instead of hand-off