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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Sufficient condition for invertibility of square FIR MIMO systems
 Douglas, S.C. ; IEEE Signal Processing Society: IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP 2010. Proceedings. Vol.5 : 1419 March 2010, Dallas, Texas, USA Piscataway/NJ: IEEE, 2010 ISBN: 9781424442959 ISBN: 9781424442966 pp.36903693 
 International Conference on Acoustics, Speech and Signal Processing (ICASSP) <35, 2010, Dallas/Tex.> 

 English 
 Conference Paper 
 Fraunhofer HHI () 
Abstract
We derive a sufficient condition for a square FIR MIMO system to have a causal and stable IIR inverse. The condition requires that the spectral norm of the normalized channel impulse response (i.e., the first tap is the identity matrix) is below a certain bound. Intuitively, this means that the system has a strong first tap. This condition often is easier to check than the usual minimumphaseness, where the roots of the systems determinant have to be computed. Simple approximations of the bound are found. Furthermore, we also give a negative result: the Wiener Filter, which approximates the inverse under low noise conditions, nevertheless always is noncausal. We apply our results to two inversion problems with causality and stability constraint. These problems arise in oversampled noiseshaping subband coding and residual interference cancellation in precoded systems, respectively.