Proceedings of the 2002 International Conference on Modal Analysis, Noise and Vibration Engineering, Leuven 2002 pages:1315-1322
Proceedings of the ISMA Conference on Noise and Vibration Engineering location:Leuven, Belgium date:16 September 2002
Frequency domain methods are known to suffer from a poor numerical conditioning when the frequency span and/or the model order become large (more than 2 decades and an order of more than 20). This numerical problem ruins both the modeling perfoemance and the model order selection capacity. This paper presents a modeling approach that leads to (almost) optimal numerical conditioning of the normal equations (condition number equal 1). The key idea is to expand the numerator and denominator of the transfer function model in a vector orthogonal basis. The theory is illustrated on a real measurement example.