• Title/Summary/Keyword: Dither Modulation/Demodulation

Search Result 1, Processing Time 0.018 seconds

Double Demodulation of a Ring Laser Dither Signal for Reducing the Dynamic Error of an Inertial Navigation System (관성항법장치의 동적오차 개선을 위한 링레이저 각진동 신호의 이중 복조방법)

  • Shim, Kyu-Min
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.42 no.1
    • /
    • pp.82-89
    • /
    • 2014
  • This paper discusses the methods for reducing the sampling time quantization errors of the body dither type ring laser gyroscope. A ring laser gyroscope has the angle quantization error which is generated by the frequency counting method of the laser beat signal and sampling time quantization error which is generated by the demodulation method for eliminating the body dithering in which the sampling periods are fitted to the dither periods. Generally, because the dither periods are longer than the calculation periods of the inertial navigation system, vehicle navigation errors are produced by long time attitude update missing during the vehicle move with a high dynamical motion. In this paper, the double demodulation method is proposed for reducing the sampling time quantization error and its effects under the dynamic situation are confirmed by simulation.