Invertibility and inverses of linear time-varying digital filters
Song Wang, C. Zhang · IEEE Transactions on Circuits and Systems II Analog and Digital Signal Processing · 2000
This brief studies invertibility and inverses of linear time-varying digital filters in the form of ARMA equation with time-varying dynamic order and relative degree. It presents a necessary and sufficient condition for the d-shift invertibility of linear time-varying filters and computational procedure for obtaining the d-shift left and right inverses. A necessary and sufficient condition for stability of inverse filters is given.