Normalization of 4QAM and 16QAM?

[bee]

Can anyone tell me by which factor should we normalize 4QAM and 16 QAM to have unit signal power or energy?

waitig....[/b]

 

[brmadhukar]

1/√2 and 1/√10

 

[bee]

can u plz tell how u calcultate this ?

 

[digicomm]

Here is a good explannation,

http://www.dsplog.com/2007/09/23/scaling-factor-in-qam/

 

[elecstudward]

Here is a good explannation,

Scaling factor in QAM

Hi, Digicomm, thank you for the link, it's explained clearly there.

I just want to make sure 1 thing, from the example in the link that you gave, for 16-QAM, the average energy is 10 but the scaling factor is sqrt(10), is it because the RMS value is used instead of the abs value?

Will be waiting for the answer. Thank you

 

[digicomm]

Hi, Digicomm, thank you for the link, it's explained clearly there.

I just want to make sure 1 thing, from the example in the link that you gave, for 16-QAM, the average energy is 10 but the scaling factor is sqrt(10), is it because the RMS value is used instead of the abs value?

Will be waiting for the answer. Thank you

The first one is energy, the second one is amplitude.

 

[elecstudward]

The first one is energy, the second one is amplitude.

so because we are scaling the signal, we scale the amplitude, and it is sqrt(energy)?