Rank 1 higher than rank 2 with QCI 11

Hi Experts.
For LTE, with CQI value 11 it’s observed that rank 1 sample % is high in compare to rank 2.
What can be reason?
It’s known that UE reported rank depends on radio conditions. If it good more probability of better rank.

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Rank depends on multipath RF not on good RF.

Rank depends on SINR.

Ok.
Someone told me depends on SINR as well which linked with reported CQI so I’m thinking with CQI 11 why rank 1 % higher?

Any parameter which can help here?
I turned on fast mimo switch already to compensate fading and all.

What is pmi index. Also what is TM?

Tm4 2x2 closed loop

You should see your log files.
Maybe it could be due to swapped feeders.

Oh yes 1 of reason good :+1:

And what to check please tell to improve rank 2 %?

Is ths rank reported by UE or scheduled by eNb?
And is any GBR bearer setup?

Reported by UE.

As @RFSpecialist said, rank is completely depend on multipath, but still in such good RF condition RI=1 continuosly not expected.

I remember, I also faced same issue long time back.
But surprisingly for another handset at same location with same CQI, RI was better than first handset.

Multipath point is ok but I believe depends on good radio conditions as well.

We can improve sinr only that we can do by tilt / power change so rank as well.

Any parameter there will be helpful…

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If you are closer to site, even small change in location affect RI.

That’s why we struggled to get peak tput with RI=4 for NR. RI randomly change between 2/3/4 at same location.

Ya agree. In NR very difficult to maintain rank 4 I remember how difficult to achieve sweet point we called where rank 4 achieve :grin:

Surprisingly LTE we can expect rank 2 samples high with cqi 11, but results reverse rank 1 samples high. So thinking what can be reasons.

1 good suggestion for feeder swap, which can be check.