Hyperstable adaptive IIR algorithms with polyphase structures: analysis and design

We consider adaptive identification algorithms based on hyperstability concepts with polyphase structures. The SPR condition required for convergence of these schemes can be always met by using a sufficiently high polyphase expansion factor M. The degree of persistent excitation required for parameter convergence is obtained. If some a priori knowledge about the system to identify is available, a compensating filter can be designed to avoid the need for a high M.