Title :
Comparison of discrete-time approximations for continuous-time nonlinear systems
Author :
Koeppl, H. ; Schwingshackl, D.
Author_Institution :
Christian Doppler Lab. for Nonlinear Signal Process., Graz Univ. of Technol., Austria
Abstract :
This work addresses the problem of approximating the sampled input-output (i/o) behavior of continuous-time nonlinear systems using discrete-time Volterra models. For an exactly band-limited nonlinear system for which a Volterra representation exists, the discrete-time Volterra model exactly corresponds to the sampled continuous-time Volterra kernels. Physical systems, as they are causal, are never exactly band-limited. Thus, a modeling error is introduced. By relaxing the causality condition and allowing a small processing delay, it is shown through simulation that more accurate discrete-time Volterra models, compared to sampled continuous-time Volterra models, can be generated.
Keywords :
Volterra series; continuous time systems; discrete time systems; nonlinear network analysis; nonlinear systems; signal sampling; Volterra representation; Volterra series expansion; band-limited nonlinear system; causality condition relaxation; continuous-time nonlinear systems; discrete-time Volterra models; discrete-time approximations; linear filters; modeling error; processing delay; sampled continuous-time Volterra kernels; system sampled input-output behavior; Analog circuits; Delay; Digital circuits; Frequency; Kernel; Laboratories; Nonlinear systems; Sampling methods; Signal design; Signal processing;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 2004. Proceedings. (ICASSP '04). IEEE International Conference on
Print_ISBN :
0-7803-8484-9
DOI :
10.1109/ICASSP.2004.1326399