Noise Analysis of a Passive Resonant Laser Gyroscope

Abstract

Large-scale laser gyroscopes have found important applications in Earth sciences due to their self-sufficient property of measurement of the Earth’s rotation without any external references. In order to extend the relative rotation measurement accuracy to a better level so that it can be used for the determination of the Earth orientation parameters (EOP), we investigate the limitations in a passive resonant laser gyroscope (PRG) developed at Huazhong University of Science and Technology (HUST) to pave the way for future development. We identify the noise sources from the derived noise transfer function of the PRG. In the frequency range below 10−2Hz, the contribution of free-spectral-range (FSR) variation is the dominant limitation, which comes from the drift of the ring cavity length. In the 10−2 to 103Hz frequency range, the limitation is due to the noises of the frequency discrimination system, which mainly comes from the residual amplitude modulation (RAM) in the frequency range below 2 Hz. In addition, the noise contributed by the Mach–Zehnder-type beam combiner is also noticeable in the 0.01 to 2 Hz frequency range. Finally, possible schemes for future improvement are also discussed.

Effects of temperature variations in high-sensitivity Sagnac gyroscope

“…1). Large frame high-performance HL passive optical gyroscopes have been also recently reported [3,[10][11][12][13].…”

Laser gyro signal filtering by combining CEEMDAN and principal component analysis

“…How to effectively reduce the random drift of the gyro and improve the output accuracy of the signal has always been a hot and difficult point in laser gyro [2]. There are currently two main methods to reduce gyro random drift [3]: one is to establish a time series model of the gyro random drift, and the Kalman filter and more are used for random drift compensation based on this; the other is to use wavelet transform and more to reduce the noise of the gyro output data. Since the gyro signal will be interfered by a variety of uncertain factors, the random drift has the characteristics of slow time-varying, nonlinear, and nonstationary, which makes it impossible to establish an accurate drift model.…”

“…Since the gyro signal will be interfered by a variety of uncertain factors, the random drift has the characteristics of slow time-varying, nonlinear, and nonstationary, which makes it impossible to establish an accurate drift model. Therefore, a time series model is difficult to obtain the ideal compensation effect, and the current gyro signal processing mainly adopts noise reduction method [3].…”

Effects of temperature variations in high sensitivity Sagnac gyroscope

“…New HL apparatuses assembled onto a rigid monument supporting the mirrors metallic boxes have been developed in the last decade [3,4,5,6]. Large frame high-performance HL passive optical gyroscopes have been also recently reported [7,8,9,10,11].…”