TM9 mode gains in LTE for TDD and FDD

Hi Experts,

Anyone worked over TM9 mode in LTE for TDD and FDD need to check gain as compared to other TM modes?

We have option of configuring max 8 ports with TM9 ie 15 to 22 for CSI-RS.
Need to check, at present, what config used in network.

Admin note: this post was updated with image below.

What advantage of deploying tm9?
(Benefits of tm9 vs tm8 deployment in LTE, if work on same in network)

One of the major benefit is TM8 supports upto dual layer transmission while TM9 introduce support of upto 8 layers for SU & MU both.

TM9 and TM8 largely depends in network infrastructure.
If eNB has high density antenna arrays which can support MU-MIMO then think TM9 is certainly better.
If not then Tm8 will also probably give better capacity improvements

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Thanks dears.

Tm8 basically deploy over sites where congestion is high mainly for capacity gain with rbg sharing algorithm for UE in pairing

For tm9 what I read it’s on basis of csi-rs where we have 2,4,8 layers per UE so need to check what gain over here with tm9.

Does it support MU-MIMO like tm8?

Yes. Look at the decision tree in the link I sent. TM9 is close loop MU MIMO.

Yes TM9 supports MU MIMO as well as per my understanding.
In TM8 if MU MIMO is used every user can get maximum of 2 layers and total of 8/16 layers but in TM9 each UE can get more than 2 layers while being in pairing.
Higher layers yield better throughput.
Of course there are other changes as well like TM8 have feed back SRS based while in TM9 DMRS & CSI RS are used.

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With tm9 as it’s mentioned it support 8x8 mimo for single user so can I assume 8 layer per user.
So with 2 users in pairing we have 16 layers.
In contrary tm8 having max 2 layers per users so for 16 layers we need 8 users in pairing.

I have same understanding.

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Yes antenna ports 7 to 14 used to transfer these 8 layers in tm9 like we have ports 7, 8 for tm8.

Other working hands on tm9 can further confirm.

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