The state-space model ss can be given as StateSpaceModel, where a, b, c, and d represent the state, input, output, and transmission matrices in either a continuous-time or a discrete-time system:
continuous-time system
discrete-time system
If ss is observable, the eigenvalues of will be , where is the computed estimator gain matrix.
The observer dynamics are given by:
continuous-time system
discrete-time system
In the case of a square nonsingular matrix , the state vector can be computed as .
The Ackermann method is used by default for systems with exact values:
For inexact systems with multiple output channels, the Ackermann method selects the output channel for which the observability matrix has the smallest condition number:
The second output has the lower condition number:
The gains associated with the first output:
The KNVD method uses all available outputs to estimate the states: