Hierarchical maximum likelihood gradient-based iterative identification methods for multivariable systems
摘要
This paper presents novel iterative parameter identification methods for multivariable autoregressive output-error moving-average systems. A multivariable system is decomposed into several subsystems to reduce computational complexity, and the corresponding identification models are derived. By means of the maximum likelihood principle, an auxiliary model maximum likelihood gradient-based iterative (AM-ML-GI) algorithm is developed to achieve accurate parameter estimation. To further improve the identification efficiency, a hierarchical auxiliary model maximum likelihood gradient-based iterative (H-AM-ML-GI) algorithm is proposed by using the hierarchical identification principle. A detailed floating point operation analysis shows that the H-AM-ML-GI algorithm achieves higher computational efficiency than the AM-ML-GI algorithm. Simulation results demonstrate the effectiveness of the proposed algorithms in identifying the multivariable system with high parameter estimation accuracy.