assume your OFDM block to transmit is s(n).

The channel which is rich in multipath in your case is h(n) = [h1 ... hN] with N channel taps. In the case of rayleigh fading each tap follows a complex gaussian distrbution.

So, if you receive

y(n) = conv(s,h); 

Note that h is a different realisation of a complex Gaussian at each transmission block.

Same goes for Rician but the taps follow a Rician distribution.

Hi

You can use this command in MATLAB:

h = rayleighchan(ts,fd,tau,pdb)

for more information about this code refer to MATLAB help.

Good Luck

i have already simulated this question, here i attach programs for you

enjoy

Thanks for your answers'