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Hi,
I am very new at this topics and I am now studying on an ofdm simulatio
with a blind channel estimation.I can do a basic ofdm simulation but i
fact I have a rayleigh fading channel with doppler shift and for makin
good blind estimation I must develop some algorithms to eliminate dopple
shifts.Is there anyone that can give me some help?
Thanks for your attention...
Burkay ETÝLER
burkaye@hotmail.com

burkaye wrote:

I must develop some algorithms to eliminate doppler shifts.

Could you explain more detail about what the meaning of eliminating
doppler shifts is? To my understating, the amount of doppler shift in
the channel is a one which is related to the channel estimation but
there is no way to eliminate it since it is already happened. Regarding
to the channel estimation, if the amount is large, the period of pilot
symbol averaging is to be shorter, otherwise it is to be longer. Note
that the longer period of pilot symbol averaing improves the quality of
the estimated channel information value, which obviously improves the
decoding performance of receivers.

To obtain the information related to the amount of dopper shift, we
usually estimate the channel correlation coefficient, which is give as a
function of the amount of doppler shift. For example, in Rayleigh fading
channels, the correlation coefficient is represented as

rho = bessel( tau)

where tau is the amount of doppler shift.

-James Gold