Parafac Based Blind Estimation Of Mimo Systemswith Possibly More Inputs Than Outputs

We consider the problem of frequency domain identification of a convolutive multiple-input multiple-output (MIMO) system driven by white, mutually independent unobservable inputs. In particular, we improve upon a method recently proposed in Y. Yu and A.P. Petropulu (2005) that uses PARAFAC decomposition of a tensor that is formed based on third-order statistics of the system output. The approach of Y. Yu and A.P. Petropulu (2005) utilizes only one slice of the output tensor to recover one row of the system response matrix. We here propose an approach that fully exploits the information in the output tensor. As a result, the proposed method not only achieves lower error values but also becomes applicable to MIMO systems with possibly more inputs than outputs. By combing two output tensors, we can make the approach applicable to more systems. We also extend the method to employ fourth-order statistics of the system output