You can do it yourself. The received signal in frequency selective channels is:
\[y_n=\sum_{l=0}^Lh_lx_{n-l}+z_n\]
where h, x and z are the channel coefficients, transmitted signal and AWGN. If you write this for n=1, ..., N, you will get the recived signal:
\[\mathbf{y}=\mathbf{H}\mathbf{x}+\mathbf{z}\]
where y, x, and z here are N-by-1 vectors, and H is an N-by-N matrix. If you know this, you can construct H, multiply it with x, and add to it z, and then you get y.