Direct nonlinear parameter estimation method for a phase generated carrier position sensor.
Opt Express
; 31(15): 24702-24716, 2023 Jul 17.
Article
em En
| MEDLINE
| ID: mdl-37475290
ABSTRACT
Phase generated carrier (PGC) is widely applied in interferometric phase estimation for distance, vibration and velocity measurements. However, traditional PGC methods suffer from nonlinear effects, causing limitations to demodulation of signal. Modified PGC methods, such as ellipse fitting algorithm (EFA), resolves these issues, but usually requires additional phase shift. With our proposed method in this paper, only one period of signal and one test point is required to attain accurate depth of phase modulation and phase. We use a photodiode to calibrate light intensity in data acquisition, and develop a Levenburg-Marquadt algorithm to estimate values of PGC parameters. An improved algorithm is also proposed to avoid local optimization based on prior information to ensure measurement stability. Less than 5 × 10-3â
rad phase measurement uncertainty and over 55â
dB Signal to Noise and Distortion Ratio (SINAD) is obtained in experiment.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Opt Express
Assunto da revista:
OFTALMOLOGIA
Ano de publicação:
2023
Tipo de documento:
Article