I don't understand MIMO :(

Hi guys,
I started studying about 5G NR and discovered that I don’t really understand about how MIMO or antenna /antenna elements work. Can somebody help me here?

Let’s take LTE for example, with simple 2x2 MIMO. So eNodeB is supposed to have two TX here, right? Does that mean the same data is being transmitted by two separate antennas here ? Each antenna has it’s own beam? So 2x2 MIMO means two beams from same eNodeB covering a particular cell?

And do both of these beams operate in same bandwidth and carrier frequencies and carry the same data? If that’s so, I mean, if both of these beams carry the same data and operate on same frequency, why is it necessary to place two beams here? Since the antenna TX ports are just inches apart and an UE could receive same data from only one beam or TX?

In fact, I was checking some introductory slides on 5G MIMO and whole beam or antenna parts got me confused. There are going to be follow up questions from me, I just wish I could understand the basics before delving into this big and complex topic.

Thanks in advance. Stay safe.


Hello @Elon20.

You re in the right place to learn, and with a lot of Experts to help.

Why don’t you star by doing a SITE SEARCH?

For example for MIMO, this would be the query:


This way you will find a lot of MIMO discussions, by Relevance:

But maybe you want to find the LATEST DISCUSSION with MIMO:


Either way, i am pretty sure you will find a lot of useful information.

And of course, you can search any term you want.

With thousands of experts, and also thousands and thousands of (good) discussions, you have the opportunity to understand MIMO and also a lot in Telecom. :wink: