Narrowband channel Matlab Wireless Communication

Hi everyone, I've one problem with the narrowband channel. Please for your help! In this addresses are the problems!

http://homeandgardens.webuda.com/narrowband.png

http://homeandgardens.webuda.com/explication.png

It's part from Wireless Communication.

I started with this values, but I'm not sure it's a correct!

U = 0:2*pi;
h = zeros(1, 500);
alfa = input('Input alfa: ');
fi = input('Input fi: ');
j = input('Input j: ');
e = exp(-j*rand(0, 500);

[Walter Roberson]

It is unlikely that U should go from 0 to 2*pi by 1's.

You are missing the ")" for the "exp("