TDD/FDD twin beam

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Hi All,
Any one has an idea, as TDD payload dip observed after “TWIN BEAM” live in Co-Lo FDD – note (TDD-Twin beam) already there?
In Nokia System (antenna also same - via diplexer it’s configured).
What could be the reson due to this?

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Traffic can dip due to two reasons, coverage shrinking or shifting of traffic from TDD to FDD.

So need to check what is the case is there increase in load balancing or shift of traffic from TDD to FDD or is there reduction in TDD coverage.

Also not clear what is twin beam we have dual stream beamforming but i am not sure of twin beams but first of all we need to know what caused the reduction in traffix of TDD:

  1. Is it due to traffic shift from tdd ti FDD;
  2. Is it due to coverage loss on TDD;
  3. How about other sites where change was not done (is it any network trend)

Only after we determine this we can comment further usually.

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Great @Waddah_Ambrais.
In addition, if you can also if pre and post RS power configuration mismatch with MIMO configuration change in both band.
Sometimes cross feeder issue can also help.
We can check it with RSSI or Rank2 trend.

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Thanks @Waddah_Ambrais.
Actually twim beam is concept there antenna is same where TDD or FDD one sector in that logically we split with two sector that’s called twim Beam.
But in my case where already TDD running in with single or split in 1-antenna so FDD also came in that antenna with the help of diplexer so what happen beam are privously 1 or 2 but now it’s 4 -and each are 33 dbm like that so little payload dip is justified due to paneteration different in both the technology, but here huge payload dip observe.
Let’s say in pre -150 gb but Post 40 or 50 GB like that, also it’s not shifted to fdd as well that is the concern.

So majority of the cases came due to connectivity issue.
But how we can get directly from radio counter that particular sites having issue.
Also in some cases we resolve after rectification of connection part.

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Pre and post power also same and also no changes in scf it reamin same like master sectors.

Yes i already checked mimo rank counters as well code word counter it’s shows minor changes no drastically but it apply in both good as well as bad sites so we can’t justify it post Twin beam.

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@tsaurabh, let make it simple: twin beam that means logically you are upgrading from 3 sectors sites to 6 sector with 30 degree of separation?
And connectivity issue is like cross feeder or change of cpri cable in tx and rx branch, right?
Also help us to understand what mimo configuration has implemented in fdd and tdd?
Is it 2t2r or 4t4r in pre and post scenarios?
Please suggest.

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Pre-post same 4T4R to 4T4R in TDD.
And in same antenna with help of diplexer FDD is conect with 2T2R.

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Yes Its Logically 6 Sector with 3 Sector Antenna and in the same antenna FD-TD both are working with Diplexer