New waveforms in 5G NR

Hi Experts,

For NR it’s mentioned CP-OFDM used in DL/UL along with DFT-S-OFDM for UL to improve coverage.

Can anyone tell what new waveform F-OFDM, GFDM, etc… indicated for NR?
Why these new waveform introduced?

Basically because OFDM has some drawbacks, specially related to PAPR and Frequency location.

Check the images that I uploaded on LinkedIn:

High PAPR and OOBE motivated the analysis for new access techniques:

Here one comparison between the OOBE between different techniques:

Thanks @Jairo_Sanz. Is it part of Rel 16 ,17?
Not able to find such new waveform terminology in NR books or any 5G training attended.
So we can say now CP- OFDM not used for NR in DL/UL.
Is understanding correct?

Those new waveforms are still under investigation and for new releases.
As you mentioned earlier, CP-OFDM (UL/DL) and DFT-S-OFDM are used at the moment for NR.

Ok thanks understood! :+1:

You can find it in “5G New Radio in Bullets” book, read Pi/2 Bpsk modulation topic.

Waveform type for NR will still be either OFDM or DFTsOFDM, they just added new modulation scheme of pi/2 BPSK.
I guess in R16.
And this mod scheme will be applicable to DMRS as well.

Yes for Uplink coverage boost new modulation type pi/2 BPSK is introduced which uses DFT-S-OFDM waveform (always applicable in uplink only).
For example, PUSCH format 3 & 4 using this waveform.
Even PUSCH DMRS can also use this.
Refer 2.9.2 Topic in “5G New Radio in Bullets” book.

Yes agree.
New waveform which mentioned F-OFDM, GFDM, etc… not mentioned for pi/2 bpsk.

DFT-S-OFDM introduce particularly for pi/2 bpsk.
To boost uplink coverage.
New waveform which point out yesterday I don’t think mentioned in NR in bullets…

F-OFDM, GFDM, etc… new waveform not yet mentioned.
I find over sharetechnote, new waveform section there.

Mentioned by @Jairo_Sanz, as well over Linkedin.
But I think these are under discussion only…

Few days back I saw @RFSpecialist posting for F-OFDM so I just explore it but not get much info.

Huawei clearly mentioned they use F-OFDM.

Yes :+1:.
Not able to seen for Nokia.

But I think everyone use it otherwise cannot match BS specs.
There are so tight specs to match.
Impossible to do it without F-OFDM.

Any parameter for this at gNB / eNB end?

No, for sure there isn’t any.
How can someone mess around with filters?
This is part of factory testing and calibration.

Then it can be there, as I m not gone deeply in hardware side architecture.

I am sure there hidden for factory and internal traces.

May be R&D person use to play with it daily basis.

But not for MNOs.
Huawei has so many live traces that you get lost among them.
Cell, gnodeB, user, interference, beams, layers.
You name it and it’s there.
But there might be alarms for this, let me check.

Alarms when f-ofdm doesn’t work well anymore
Just checking some alarms and noticed this:
Major alarm but cell is degraded, some UEs cannot access cell, let’s say 10 antenna elemenst are faulty out of 128 for example.
Should the cell operate this way or not?

There are discussions on the new waveforms here

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