Figures and
show the same example as in Figures
and
.
What is new here is that the proper PEF
is not given but is determined from the data.
Figure was made with a three-coefficient filter (1,a1,a2) and
Figure was made with a five-coefficient filter
(1,a1,a2,a3,a4).
The main difference in the figures is where the data is sparse.
The data points in Figures
,
and
are samples from a sinusoid.
subsine390
Figure 26
Interpolating with a three-term filter.
The interpolated signal is fairly monofrequency.
subsine590
Figure 27
Interpolating with a five term filter.
Comparing Figures
and
to
Figures and
we conclude that by finding and imposing
the prediction-error filter
while finding the model space,
we have interpolated beyond aliasing in data space.