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Es/No and Eb/No in OFDM system

Started by partypooper May 11, 2008
hi all,

I"m working on a simulation of comparing OFDM with different modulation
schemes (QPSK,QAM) etc'...
My question is about the conversion from Es/No to Eb/No
I'm not sure if I need to take the cyclic prefix under consideration
for instance:

Es/No=Eb/No+10log10(log2M * Nc) + 10log10(CodeRate) + ...
.. 10log10(Tinf/(Tinf+Tcp))

is the last part correct?


where
Tinf - is the information period
Tcp - is the added Cyclic prefix period
Ttot = Tcp+Tinf


- thanks


On May 11, 4:27 pm, "partypooper" <sshango...@hotmail.com> wrote:
> hi all, > > I"m working on a simulation of comparing OFDM with different modulation > schemes (QPSK,QAM) etc'... > My question is about the conversion from Es/No to Eb/No > I'm not sure if I need to take the cyclic prefix under consideration > for instance: > > Es/No=Eb/No+10log10(log2M * Nc) + 10log10(CodeRate) + ... > .. 10log10(Tinf/(Tinf+Tcp)) > > is the last part correct? > > where > Tinf - is the information period > Tcp - is the added Cyclic prefix period > Ttot = Tcp+Tinf > > - thanks
I didn't check your equation, but I think it is appropriate to include the cyclic prefix as overhead in your Eb/No calculation. When I see Eb/ No, I think "energy per information bit over noise power spectral density". This would suggest that the energy spent on the cyclic prefix doesn't count, much how you must account for the code rate in your calculation. Jason