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Updated: Feb 19, 2026

Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
Note: Demodulation of spectral signal modulated by optical chopper with unstable modulation frequency
Shengzhao Zhang1, Gang Li1, Jiexi Wang2
1State Key Laboratory of Precision Measurement Technology and Instruments, Tianjin University, Tianjin 300072, China.
Abstract:
When an optical chopper is used to modulate the light source, the rotating speed of the wheel may vary with time and subsequently cause jitter of the modulation frequency. The amplitude calculated from the modulated signal would be distorted when the frequency fluctuations occur. To precisely calculate the amplitude of the modulated light flux, we proposed a method to estimate the range of the frequency fluctuation in the measurement of the spectrum and then extract the amplitude based on the sum of power of the signal in the selected frequency range. Experiments were designed to test the feasibility of the proposed method and the results showed lower root means square error than the conventional way.
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