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electron
2010-12-11, 02:03 AM
Hi friends,


Can any body please explain how we can identify Cross feeder(Partial swap) in 3G sites by drive test?


Thanks

Alex_R
2010-12-11, 02:09 AM
you can identify a point which should be served by S1 and check RSCP Ec/No if it is good but with different Scrambling Code (SC) for example S2

hence you face cross sectors

if in this point you can see RSCP Ec/No for both S1 & S2 with good level and in another area both with bad level (RSCP)

hence you face cross feeders

rimoucha
2010-12-11, 01:17 PM
Hello Electron,

I abolutely agree with Alex.Attached is an example :)

Best regards,

TEMS
2010-12-11, 06:33 PM
Hi friends,


Can any body please explain how we can identify Cross feeder(Partial swap) in 3G sites by drive test?


Thanks

Hi friend
can check it on Nemo Analyzer
please see example bellow

FFETIQUE
2010-12-12, 10:06 AM
You just need to know azimuth and scrambling code from each sector and to check if its correct during drive test.

Ericsson_RND
2010-12-12, 12:36 PM
Hi All,
Can some body explain to me how can we recognize by TEMS if one of the feeders of sector A is connected to DRU 1 and the other connected to another DRU by mistake,

Regards
Ahmed Al-Shawi

mon3em
2010-12-12, 07:55 PM
sala7 is right

Also you will find UE transmitting @ maximum power even close to site... cuz you are losting the Div gain.

mon3em

tsiz
2010-12-12, 11:20 PM
Hi All,
Can some body explain to me how can we recognize by TEMS if one of the feeders of sector A is connected to DRU 1 and the other connected to another DRU by mistake,

Regards
Ahmed Al-Shawi

You will need to block each radio separately and drive test with one radio and see where it serves..if it serves in the wrong area, you have a swapped sector.

Ericsson_RND
2010-12-13, 12:03 AM
Dear TZIS and Sala7

Thanks for your feedback.


Regards
Ahmed Al-Shawi

sala70vic
2010-12-13, 01:03 AM
You will need to block each radio separately and drive test with one radio and see where it serves..if it serves in the wrong area, you have a swapped sector.

adding:
the above method is perfect if the swapped feeders belong to Tx/Rx main ones.

If the swapped feeders belong to Rx diversity so try to monitor RTWP of both feeders "same DRU" at the same time all over the day, you should find a big difference.

thanks,
regards,

singgih
2010-12-13, 09:30 AM
drivetest all site's coverage area with SC locked to SC's site. than we can analyze of logfile.

if its wrong SC at any S1/2/3, its cross sector
if there's 2 dominant SC , you face cross feeder.


BR//

Singgih

Nipon
2010-12-16, 11:17 PM
adding:
the above method is perfect if the swapped feeders belong to Tx/Rx main ones.

If the swapped feeders belong to Rx diversity so try to monitor RTWP of both feeders "same DRU" at the same time all over the day, you should find a big difference.

thanks,
regards,

I agree with sala70vic, if the cross feeder is only Rxdiver, drive test may not help to investigate. however the RTWP between Rxmain and Rxdiver, even not cross, may not be totally equal, but not big difference.

One method I think can analyse is, if you can lock only Rxdiver, and monitor UL statistic, if the Rx cable is swap, stat might not impact.