N=32;

NumInputs = 2;

Bits=rand(NumInputs ,N)>=0.5;

BR

You may use LFSR http://en.wikipedia.org/wiki/Linear_feedback_shift_register 

If you've got just one gate, there's no reason *not* to use exact enumeration: there are 4 possible input states, that can be labeled by an integer: 0,1,2 and 3 whose binary digits are the inputs.