Amplitude Spectrum Design for Multivariable System Identification in Open Loop

In this paper, perturbation signal design for multi-input multi-output (MIMO) systems is presented for the output error (OE) and the autoregressive with exogenous inputs (ARX) model structures. The problem is handled via the investigation of multi-input single-output (MISO) systems, since a MIMO system can be formed as a combination of MISO systems. Comparison is performed between the flat, MOOSE2 and optexcit signal designs under three different signal-to-noise ratios (SNRs) in the open loop setting. The effectiveness of signal designs obtained for the single-input case and applied on MISO systems is analysed. The mean determinant of the covariance matrix of parameter estimates is utilised as a measure of estimation accuracy. Equations for MISO system are constructed and the amplitude spectrum design of perturbation signals is investigated based on the determinant of the covariance matrix for the ARX model structure.