When finite precision is used to represent the coefficients
two problems arises. First, the coefficient quantization
modifies the pole location and thus the frequency of the
generated sine wave. This problem appears especially in
the case of direct form realization. Second, the poles for
the coupled form cannot be placed always on the unit circle
and as a consequence the amplitude is not constant. It
will increase (decrease) in time if the poles are outside
(inside) the unit circle. Thus in order to preserve the
advantage of the coupled form oscillator a method to cony