Micro-Doppler vibration measurement system and method based on bidirectional acousto-optic frequency comb
A technology of vibration measurement and frequency comb, which is applied in the direction of measuring devices, measuring ultrasonic/sonic/infrasonic waves, instruments, etc., can solve the problems of reducing detection bandwidth requirements and limiting application range, and achieves the effect of ensuring adaptability and reducing bandwidth requirements
Active Publication Date: 2021-10-08
SHANGHAI INST OF TECHNICAL PHYSICS - CHINESE ACAD OF SCI
View PDF10 Cites 1 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Due to the directionality of the Doppler frequency shift, the traditional acousto-optic frequency comb can only reduce the detection bandwidth requirements for the measurement of targets moving in a certain direction, which greatly limits its practical application range
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
[0022]The implementation of the present invention will be described in detail below in conjunction with the accompanying drawings and an embodiment of micro-Doppler vibration measurement of a moving target based on a pulse-injected bidirectional acousto-optic frequency comb in the 1530nm band.
[0023] The main devices adopted in the present invention are described as follows:
[0024] 1. Seed laser 1: a frequency-stabilized distributed feedback laser diode with a central wavelength of 1529.55nm (FRL-15DCWD-A81-19600-C, FITEL), fiber-coupled output.
[0025] 2. The first optical fiber coupler 2, the second optical fiber coupler 4, and the third optical fiber coupler 14: produced by RUIK Company, the splitting ratios are 90:10, 50:50, and 50:50, respectively.
[0026] 3. Fiber delay line 5: PM1550 polarization maintaining fiber about 1 km long.
[0027] 4. Narrowband filter 7, circulator 12, and optical collimator 13: manufactured by RUIK, the narrowband filter bandwidth is 10...
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 discloses a micro-Doppler vibration measurement system and method based on a bidirectional acousto-optic frequency comb, and the system firstly modulates a seed laser and then injects the modulated seed laser into a frequency shift loop which comprises an optical fiber delay line, an optical amplifier, a narrow-band filter, a special frequency shift configuration capable of forward or reverse frequency shift, and a driver of the special frequency shift configuration. Finally, the pulse type bidirectional acousto-optic frequency comb is output, passes through the optical amplifier, the circulator and the optical collimator and then is output to a detection target. A target echo signal is combined with the single-frequency seed laser through the optical fiber coupler to obtain a multi-heterodyne beat frequency signal, so that micro-Doppler vibration measurement of the moving target is realized. The system has the advantages that the intermediate frequency signal containing the micro-Doppler vibration information of the high-speed moving target can be obtained under the low detection bandwidth, and therefore the vibration characteristic of the high-speed moving target can be accurately inverted.
Description
technical field [0001] The invention relates to Doppler vibration measurement and generation technology of acousto-optic frequency comb, in particular to a micro-Doppler vibration measurement system and method based on two-way acousto-optic frequency comb. Background technique [0002] Laser Doppler vibration detection technology is a non-contact, high-resolution, high-precision vibration detection technology based on the Doppler effect. This technology has been widely used in the fields of aerospace, biomedicine, precision machining and ultrasonic testing. The basic principle is to use the Doppler effect of the echo signal of the vibrating target to invert the vibration characteristics of the target in the laser irradiation direction. In actual measurement, it is often necessary to measure a moving target, which will cause the micro-Doppler signal of the target vibration to be superimposed on the Doppler frequency shift signal of the macro-motion of the target. At this ti...
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 Applications(China)
IPC IPC(8): G01H9/00
CPCG01H9/004
Inventor 陈滔陈新孔伟乐文杰尹路舒嵘
Owner SHANGHAI INST OF TECHNICAL PHYSICS - CHINESE ACAD OF SCI