The CCDE is given, but I was trying to derive it on my own and now I am stuck.
first of all, the reverse y[n] when goes through the delayed system, it turns to y[n-M]. then when it passes through the leaky integrator system, $y'[n-M] = (1 - \lambda) * y[n-M] + \lambda * y'[n-M-1]$
combining two, $y[n] = x[n] + \alpha * y'[n-M]$ $ = x[n] + \alpha * (1 - \lambda) * y[n - M] + \alpha * \lambda * y'[n-M-1]$
Now, I am stuck. Can anyone help me with it? Did I understand something wrong?