To apply (2.27), we need the FIM
or the CR bound covariance (inverse of FIM).
The CR bound for AR parameters is well known [25].
We have

where is the auto-correlation
matrix.
Note that
has asymptotically
determinant 1.
The CR bound for is independent of
and given by

The function `software/module_ar_ml.m` implements this.
We compare this method with other approaches in Section 9.4.10.

Baggenstoss
2017-05-19