Title :
Equation-error closed-loop system identification using cyclic spectral analysis
Author :
Tontiruttananon, Channarong ; Tugnait, Jitendra K.
Author_Institution :
Dept. of Electr. Eng., Auburn Univ., AL, USA
Abstract :
The problem of closed-loop system identification given noisy input-output measurements is considered. The closed-loop system operates under an external cyclostationary input which is not measured. Noisy measurements of the (direct) input and output of the plant are assumed to be available. The various disturbances affecting the system are either stationary or cyclostationary with cycle frequencies different from the input cycle frequencies. The closed-loop system must be stable but it is allowed to be unstable in open-loop. A frequency-domain parametric solution is proposed and analyzed using an equation error formulation, and cyclic spectrum and cross-spectrum of the input-output measurements. The parameter estimator is shown to be consistent. A simulation example using an unstable open-loop system is presented to illustrate the proposed approach.
Keywords :
closed loop systems; convergence of numerical methods; error analysis; frequency-domain analysis; measurement; noise; parameter estimation; spectral analysis; stability; closed-loop system identification; convergence analysis; cross-spectrum; cyclic spectral analysis; cyclic spectrum; cyclostationary disturbance; equation-error; external cyclostationary input; frequency-domain parametric solution; input cycle frequencies; input-output measurements; noisy input-output measurements; parameter estimator; simulation; stationary disturbance; unstable open-loop system; Communication system control; Equations; Frequency domain analysis; Linear systems; Noise measurement; Nonlinear filters; Spectral analysis; System identification; Time measurement; Transfer functions;
Conference_Titel :
Signals, Systems & Computers, 1997. Conference Record of the Thirty-First Asilomar Conference on
Conference_Location :
Pacific Grove, CA, USA
Print_ISBN :
0-8186-8316-3
DOI :
10.1109/ACSSC.1997.680372