Sampling Frequency effect on OFDM

Hi,
I am doing a baseband simulation for IEEE 802.11 g. The standard uses 64
IFFT length (3.2μs) and 20 Msamples per second. I think this result in one
sample per symbol. I am wondering what the structure will be if I use 40
Msample per second, i.e will the IFFT size change, or interpolation will be
used? or what is the effect of sampling frequency on the baseband
simulation?
Best Regards,

	 

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Yes, simply double the IFFT size. This adds bins for higher frequencies
that should be set to zero to get the same result. 
Those are located in the middle of your input vector. Positive frequencies
/ subcarriers go to the left edge and negative ones to the right.

The output is at twice the sample rate, so it is an interpolation of the
lower-rate output.
	 

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