Hi,
can somebody help me how to transmit a MB-OFDM code in UWB channel? Let say I
have 200 symbols with 165 no of samples. I try to run the UWB channel model
codes from the MATLAB exchange files in the internet but I found that the
impulse response (h) matrix for 100 number of channel is 7000X100.So, how can I
relate this impulse response to my transmitted data?
TQ in advanced..
Anne Na
Reply by roge...@gmail.com●November 18, 20082008-11-18
Hi again,
I have been trying what I was telling you in this thread and I think I got it. I
do not why, but the phase of a transformed signal is different if the fftshift
is used in both the temporal and frequency domains or only in one.
I leave here the script and tell me what you think please.
Thanks.
Hi everyone, >could somebody explain to me why is it necessary to do
the fftshift(fft(fftshift(x))) where x is a 'temporal' signal?
>
>I know that the fftshift function makes a shift to fix the 0,2Pi to -Pi,Pi
problem, but why do I have to do the first ffshift?
>
>Is there any problem with the phase of the signal or something?
>
>Thanks!
Reply by Amit Pathania●November 17, 20082008-11-17
I dont see why you need 2 fftshifts; what exactly are you trying to accomplish
when you find it necessary?
Amit Pathania
--- On Thu, 11/13/08, r...@gmail.com wrote:
From: r...@gmail.com
Subject: [matlab] fftshift of the fft of the fftshift (x(t))
To: m...
Date: Thursday, November 13, 2008, 9:51 PM
Hi everyone,
could somebody explain to me why is it necessary to do the fftshift(fft(
fftshift( x))) where x is a 'temporal' signal?
I know that the fftshift function makes a shift to fix the 0,2Pi to -Pi,Pi
problem, but why do I have to do the first ffshift?
Is there any problem with the phase of the signal or something?
> Hi everyone,
> could somebody explain to me why is it necessary to do the
> fftshift(fft(fftshift(x))) where x is a 'temporal' signal?
>
> I know that the fftshift function makes a shift to fix the 0,2Pi to -Pi,Pi
> problem, but why do I have to do the first ffshift?
>
> Is there any problem with the phase of the signal or something?
>
> Thanks!
>
>
Reply by roge...@gmail.com●November 13, 20082008-11-13
Hi everyone,
could somebody explain to me why is it necessary to do the
fftshift(fft(fftshift(x))) where x is a 'temporal' signal?
I know that the fftshift function makes a shift to fix the 0,2Pi to -Pi,Pi
problem, but why do I have to do the first ffshift?
Is there any problem with the phase of the signal or something?