What is 256qam power-back off in 4G and 5G?

RAN
1

Hi Experts.
What is 256qam power-back off in 4G and 5G?

2

Value is 1.5 dB it will improve DL throughput. Linked with EVM concept.

3

Thanks @ankgitm. Yes that I understand 1.5, 3 dB passed EVM defined in 3GPP.
But trying to understand that what exactly this 1.5 dB power is doing…

It will impact in DL to because this brings more samples of 256qam, how this brings more 256qam samples?
Adaption in the modulation depends on quality so how this 1.5 or 3 dB differentiates modulation samples rate?

4

@ankgitm
Hi ankgitm
For Huawei it is 3dB for QPSK&16QAM, 3.5dB for 64QAM, 6.5dB for 256QAM , this is in UL PWR BackOff, and the power reduction of 256QAM is 3dB, So what is expected if i change it 2 or 1 for 256QAM, what about IBLER?