Fiber optic gyro (FOG) signal denoising method based on overlap M-band discrete wavelet transform (OMDWT)
A technology of discrete wavelet transform and fiber optic gyroscope, which is applied in the field of inertial navigation, can solve the problems of slow decomposition speed and non-circular movement of scale coefficients
Active Publication Date: 2014-07-02
BEIHANG UNIV
View PDF3 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
On the one hand, it overcomes the slow decomposition speed of fiber optic gyro signal processing based on 2-band wavelets, and the M-band wavelet theory provides a wider choice for the selection of wavelet bases; In M-band Discrete Wavelet Transform (MDWT), the signal is decomposed according to multi-channel; on the other hand, when the fiber optic gyroscope signal is denoised based on the 2-band wavelet, the fiber optic gyroscope signal moves circularly for a certain beat, and the DWT wavelet And the scale factor can not be circularly moved the same lack of beats
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0036] Such as figure 1 Shown, the realization method of the present invention is as follows:
[0037] 1. Establish a fiber optic gyroscope output signal model
[0038]
[0039] Among them, X t is the output signal of the fiber optic gyroscope; t=0,..., N-1, N represents the length of the output signal of the fiber optic gyroscope; ω ie is the angular rate of the earth's rotation, ω ie =7.27×10 -5 rad / s; is the geographic latitude of the test point; ε t is the gyro drift, which consists of constant component, periodic component and white noise, namely
[0040] ε t =ε d +Ω d sin(2πf d +θ 0 )+W t (2)
[0041] In the formula, ε d is a constant value component, which is approximately a constant in a short time; Ω d is the amplitude of the periodic component; f d is the frequency of the periodic component; θ 0 is the initial phase; W t is zero-mean white Gaussian noise. Ω in the formula d sin(2πf d +θ 0 ) and W t The two terms constitut...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention relates to a fiber optic gyro (FOG) signal denoising method based on overlap M-band discrete wavelet transform (OMDWT). The FOG signal denoising method comprises the following steps of: establishing an FOG output signal model at first; carrying out OMDWT wavelet decomposition on an FOG output signal; then carrying out threshold processing on an OMDWT wavelet coefficient; and finally carrying out OMDWT wavelet reconstruction on the FOG output signal to obtain a denoised gyro signal. According to the invention, in the event of denoising the FOG output signal by utilizing the OMDWT, the wavelet coefficient and the scale coefficient of the OMDWT circularly move for corresponding beats along with circular motion of the FOG signal; in the conversion process, the gyro signal is decomposed according to a plurality of channels; the FOG signal denoising method has rapider decomposition speed according to different bands, more detailed band division on the gyro signal and a denoising effect prior to the traditional wavelet denoising effect; and the FOG signal denoising method disclosed by the invention has a important meaning for increasing the navigation performance of an inertial navigation system.
Description
technical field [0001] The invention relates to an optical fiber gyro signal denoising method based on an overlapping M-band discrete wavelet transform (Overlap M-band Discrete Wavelet Transform, OMDWT), and belongs to the technical field of inertial navigation. Background technique [0002] The fiber optic gyroscope is a new type of all-solid-state gyroscope developed on the basis of the Sagnac effect. It has been highly valued by countries all over the world and has become an ideal inertial device in a new generation of low- and medium-precision strapdown inertial navigation and guidance systems. A key technology in the strapdown inertial navigation system is how to realize fast initial alignment completely autonomously, that is, to determine the initial azimuth and horizontal attitude angle of the carrier quickly and autonomously. The main factor affecting the accuracy of azimuth alignment (north-seeking) is gyro drift, and effectively eliminating gyro drift is the key to...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): G01C19/72
Inventor 崔培玲张会娟全伟
Owner BEIHANG UNIV