Title :
On the LTI properties of adaptive feedforward systems with tap delay-line regressors
Author :
Bayard, David S.
Author_Institution :
Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA
fDate :
5/1/1999 12:00:00 AM
Abstract :
It is shown that an adaptive system whose regressor is formed by tap delay-line (TDL) filtering of a multitone sinusoidal signal is representable as a parallel connection of a linear time-invariant (LTI) block and a linear time-varying (LTV) block. A norm-bound (induced 2-norm) is computed explicitly on the LTV block and is shown to decrease as N-1, where N is the number of taps. Hence, the adaptive system becomes LTI in the limit as the number of taps goes to infinity. In the more realistic case where the number of taps N is finite, the new “LTI plus norm-bounded perturbation” representation renders, for the first time, the adaptive system analyzable by standard robust control methods
Keywords :
adaptive filters; adaptive signal processing; delay lines; feedforward; filtering theory; perturbation techniques; robust control; signal representation; LTI properties; LTV block; adaptive feedforward systems; adaptive system; linear time-invariant block; linear time-varying block; multitone sinusoidal signal representation; norm-bound; norm-bounded perturbation; parallel connection; standard robust control methods; tap delay-line filtering; tap delay-line regressors; Adaptive control; Adaptive filters; Adaptive systems; Delay; Feedforward systems; Filtering; H infinity control; Nonlinear filters; Programmable control; Time varying systems;
Journal_Title :
Signal Processing, IEEE Transactions on
