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Sweeping Linearization of Wavelength Swept Laser using PID Control

PID 제어를 이용한 파장 스위핑 레이저의 스위핑 선형화

  • Eom, Jinseob (Department of Electronics Engineering, Kangwon National University)
  • Received : 2020.10.20
  • Accepted : 2020.10.29
  • Published : 2020.11.30

Abstract

In this study, a PID control method for sweeping automatic linearization of a wavelength swept laser is proposed. First, the closedloop transfer function embodying the PID control is derived. Through the simulation of the function, Kp = 0.022, Ki = 0.008, Kd = 0.002 were obtained as the best PID coefficients for fast linear sweeping. The performance test using the PID coefficients showed that linear sweeping was held up well with a 98.7% decrement in nonlinearity after the 10th feedback, and 45 nm sweeping range, 1 kHz sweeping frequency, and 8.8 mW average optical power were obtained. The equipment consists of a fiber Bragg grating array, an optical-electronic conversion circuit, and a LabVIEW FPGA program. Every 5s, automatic feedback and PID control generate a new compensated waveform and produce a better linear sweeping than before. Compared with nonlinear sweeping, linear sweeping can reduce the cumbersome and time-consuming recalibration processes and produce more accurate measurement results.

Keywords

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