阅读说明：本技术 一种三轴光纤陀螺仪用ase光源 (ASE light source for three-axis optical fiber gyroscope ) 是由 杨志怀 胡慧珠 刘铭 于 2020-11-24 设计创作，主要内容包括：本发明公开了一种三轴光纤陀螺仪用ASE光源,多段独立的掺铒光纤通过980nm波长耦合器共享一个980nm泵浦激光器,所述的掺铒光纤至少为三段,所述的耦合器的端口至少为3×3；多段独立的掺铒光纤的b端口做折纤处理,或者与一个反射镜相连从而形成双程ASE光源；采用1550nm波长耦合器将多段独立掺铒光纤输出的光波进行和波后再分为多束光波,从而提高输出光波的谱宽,进而抑制光纤陀螺仪相对强度噪声,所述的1550nm波长耦合器的端口至少为3×3。本发明可以提高三轴陀螺仪用光源集成度和降低成本,通过耦合器将多路独立的掺铒光纤输出光波进行和波后再分为多束输出光波,提高光纤陀螺仪输入光源光波的等效谱宽,实现光纤陀螺仪相对强度噪声的抑制,提高检测精度。(The invention discloses an ASE light source for a triaxial fiber gyroscope, wherein multiple sections of independent erbium-doped fibers share a 980nm pump laser through a 980nm wavelength coupler, the erbium-doped fibers are at least three sections, and the ports of the coupler are at least 3 multiplied by 3; the b port of each section of independent erbium-doped fiber is subjected to fiber folding treatment or is connected with a reflector so as to form a double-pass ASE light source; the 1550nm wavelength coupler is adopted to perform line-traveling and wave-backward re-splitting on the light waves output by the multiple sections of independent erbium-doped optical fibers into multiple light waves, so that the spectral width of the output light waves is improved, the relative intensity noise of the optical fiber gyroscope is further suppressed, and the port of the 1550nm wavelength coupler is at least 3 x 3. The invention can improve the integration level of the light source for the triaxial gyroscope and reduce the cost, and the coupler divides the multiple independent erbium-doped optical fiber output light waves into multiple output light waves after traveling and wave-back, thereby improving the equivalent spectral width of the input light source light waves of the optical fiber gyroscope, realizing the suppression of the relative intensity noise of the optical fiber gyroscope and improving the detection precision.)

1. An ASE light source for a triaxial fiber gyroscope is characterized in that multiple sections of independent erbium-doped fibers share one 980nm pump laser through a 980nm wavelength coupler, the erbium-doped fibers are at least three sections, and ports of the coupler are at least 3 x 3; the b port of each section of independent erbium-doped fiber is subjected to fiber folding treatment or is connected with a reflector so as to form a double-pass ASE light source; the 1550nm wavelength coupler is adopted to perform line-traveling and wave-backward re-splitting on the light waves output by the multiple sections of independent erbium-doped optical fibers into multiple light waves, so that the spectral width of the output light waves is improved, the relative intensity noise of the optical fiber gyroscope is further suppressed, and the port of the 1550nm wavelength coupler is at least 3 x 3.

2. The ASE light source for a triaxial optical fiber gyroscope according to claim 1, comprising a 980nm pump laser (1), a 980nm wavelength 3 × 3 coupler (2), a first wavelength division multiplexer (3), a second wavelength division multiplexer (4), a third wavelength division multiplexer (5), a first erbium-doped fiber (6), a second erbium-doped fiber (7), a third erbium-doped fiber (8), a first isolator (9), a second isolator (10), a third isolator (11), a 1550nm wavelength 3 × 3 coupler (12); wherein

A 980nm pump laser (1) is connected with a b port of a 980nm wavelength 3X 3 coupler (2),

the ports a and c of the 980nm wavelength 3X 3 coupler (2) are subjected to fiber folding treatment,

the d port of the 980nm wavelength 3 x 3 coupler (2) is connected with the b port of the first wavelength division multiplexer (3),

the e port of the 980nm wavelength 3 x 3 coupler (2) is connected with the b port of the second wavelength division multiplexer (4),

the f port of the 980nm wavelength 3X 3 coupler (2) is connected with the b port of the third wavelength division multiplexer (5),

the port c of the first wavelength division multiplexer (3) is connected with the port a of the first erbium-doped fiber (6),

the port c of the second wavelength division multiplexer (4) is connected with the port a of the second erbium-doped fiber (7),

the port c of the third wavelength division multiplexer (5) is connected with the port a of the third erbium-doped fiber (8),

the b port of the first erbium-doped fiber (6) is processed by fiber folding or is connected with a reflector,

the b port of the second erbium-doped fiber (7) is processed by fiber folding or is connected with a reflector,

the b port of the third erbium-doped fiber (8) is processed by fiber folding or is connected with a reflector,

the port a of the first wavelength division multiplexer (3) is connected with the port a of the first isolator (9),

the a port of the second wavelength division multiplexer (4) is connected with the a port of the second isolator (10),

the port a of the third wavelength division multiplexer (5) is connected with the port a of the third isolator (11),

the b port of the first isolator (9) is connected with the a port of the 1550nm wavelength 3X 3 coupler (12),

the b port of the second isolator (10) is connected with the b port of the 1550nm wavelength 3X 3 coupler (12),

the b port of the third isolator (11) is connected with the c port of the 1550nm wavelength 3X 3 coupler (12),

the d, e and f ports of the 1550nm wavelength 3X 3 coupler (12) are used as three independent output light sources.

Technical Field

The invention belongs to the technical field of optical fiber gyroscopes, and particularly relates to an ASE light source for a triaxial optical fiber gyroscope.

Background

In the optical fiber gyroscope, an erbium-doped fiber light source based on Amplified Spontaneous Emission (ASE) is adopted to suppress back reflection and scattering noise and optical Kerr effect noise in a fiber ring. The main noise sources of the optical fiber gyroscope include shot noise, thermal noise, correlated intensity noise, signal sampling quantization noise, and the like. The thermal noise and the quantization noise can be greatly suppressed by improving the light power of the light source and the front gain.

In the optical fiber gyroscope, the amplitude of a useful signal is in direct proportion to the power of a light source, the size of shot noise is in direct proportion to the square root of the optical power of the light source, and the size of correlated intensity noise is in direct proportion to the power of the light source. Therefore, when the power of the light source reaches a certain value, the correlated intensity noise becomes the most dominant noise source. At this time, the signal-to-noise ratio of the optical fiber gyro is no longer improved with the increase of the optical power.

The method can inhibit the relevant intensity noise in the optical fiber gyroscope, effectively improve the signal to noise ratio, thereby improving the detection precision and having important significance for the application of the high-precision optical fiber gyroscope. At present, methods for suppressing the relevant intensity noise of the optical fiber gyroscope mainly include: a circuit cancellation scheme, a light path cancellation scheme, an active feedback scheme based on a light intensity modulator, etc. The circuit cancellation scheme requires strict time sequence control, so that the algorithm is complex and the realization difficulty is high. The optical path cancellation scheme needs to match the amplitudes of the reference light and the signal light in real time to achieve a good suppression effect. In the active feedback scheme based on the optical intensity modulator, it is difficult to suppress the high frequency component in the relative intensity noise due to the limited bandwidth of the feedback signal.

The correlated intensity noise is due to the beat frequency of the ASE broad spectrum source, and is additive noise due to the beat frequency between the various Fourier components in the ASE source, whose magnitude is inversely proportional to the square root of the ASE source spectral width. Therefore, a plurality of independent ASE light sources can be used for carrying out summation wave, and the light beam after the summation wave is used as an input light source of the optical fiber gyroscope, so that the equivalent spectral width can be increased, and the relevant intensity noise can be effectively inhibited.

Disclosure of Invention

The invention aims to make up for the defects of the prior art and provides an ASE light source for a triaxial optical fiber gyroscope to solve the technical problem of relevant intensity noise suppression. The invention can increase the equivalent spectral width of the light wave of the input light source of the optical fiber gyroscope, and directly improve the noise suppression effect of the related intensity, thereby improving the detection precision of the optical fiber gyroscope.

The purpose of the invention is realized by the following technical means:

a kind of three-axis fiber gyroscope uses the ASE light source, the independent erbium-doped fiber of the multisection shares a 980nm pump laser through the coupler of 980nm wavelength, the said erbium-doped fiber is at least three-section, the port of the said coupler is at least 3 x 3; the b port of each section of independent erbium-doped fiber is subjected to fiber folding treatment or is connected with a reflector so as to form a double-pass ASE light source; the 1550nm wavelength coupler is adopted to perform line-traveling and wave-backward re-splitting on the light waves output by the multiple sections of independent erbium-doped optical fibers into multiple light waves, so that the spectral width of the output light waves is improved, the relative intensity noise of the optical fiber gyroscope is further suppressed, and the port of the 1550nm wavelength coupler is at least 3 x 3.

The ASE light source for the three-axis optical fiber gyroscope comprises a 980nm pump laser, a 980nm wavelength 3 multiplied by 3 coupler, a first wavelength division multiplexer, a second wavelength division multiplexer, a third wavelength division multiplexer, a first erbium-doped optical fiber, a second erbium-doped optical fiber, a third erbium-doped optical fiber, a first isolator, a second isolator, a third isolator and a 1550nm wavelength 3 multiplied by 3 coupler; wherein the content of the first and second substances,

the 980nm pump laser is connected with the b port of the 980nm wavelength 3X 3 coupler,

the a and c ports of the 980nm wavelength 3X 3 coupler are subjected to fiber folding treatment,

the d port of the 980nm wavelength 3 x 3 coupler is connected to the b port of the first wavelength division multiplexer,

the e-port of the 980nm wavelength 3 x 3 coupler is connected to the b-port of the second wavelength division multiplexer,

the f-port of the 980nm wavelength 3 x 3 coupler is connected to the b-port of the third wavelength division multiplexer,

the c port of the first wavelength division multiplexer is connected with the a port of the first erbium-doped fiber,

the c port of the second wavelength division multiplexer is connected with the a port of the second erbium-doped fiber,

the c port of the third wavelength division multiplexer is connected with the a port of the third erbium-doped fiber,

the b port of the first erbium-doped fiber is processed by fiber folding or is connected with a reflector,

the b port of the second erbium-doped fiber is processed by fiber folding or is connected with a reflector,

the b port of the third erbium-doped fiber is processed by fiber folding or is connected with a reflector,

the a port of the first wavelength division multiplexer is connected with the a port of the first isolator,

the a port of the second wavelength division multiplexer is connected with the a port of the second isolator,

the a port of the third wavelength division multiplexer is connected with the a port of the third isolator,

the b port of the first isolator is connected to the a port of the 1550nm wavelength 3 x 3 coupler,

the b-port of the second isolator is connected to the b-port of the 1550nm wavelength 3 x 3 coupler,

the b port of the third isolator is connected to the c port of the 1550nm wavelength 3 x 3 coupler,

the d, e and f ports of the 1550nm wavelength 3X 3 coupler are used as three independent output light sources.

The invention has the beneficial effects that:

1. the invention can adopt a 980nm wavelength 3X 3 coupler (or more ports) to realize that three sections of independent erbium-doped fibers share one 980nm pump laser, thereby improving the integration level of the light source for the triaxial gyroscope and reducing the cost.

2. The invention can adopt a mode of 1550nm wavelength 3 multiplied by 3 coupler (or more ports) to carry out line-stepping and then subdivide the optical waves output by three sections of independent erbium-doped optical fibers into a plurality of beams of optical waves, and improve the equivalent spectral width of an input light source of the optical fiber gyroscope to directly reduce the related intensity noise, thereby improving the precision of the optical fiber gyroscope.

3. The method has convenient engineering realization and strong adaptability.

Drawings

FIG. 1 is a schematic view showing the construction of an ASE light source for a triaxial optical fiber gyro;

in the figure, a 980nm pump laser 1, a 980nm wavelength 3 × 3 coupler 2, a first wavelength division multiplexer 3, a second wavelength division multiplexer 4, a third wavelength division multiplexer 5, a first erbium-doped fiber 6, a second erbium-doped fiber 7, a third erbium-doped fiber 8, a first isolator 9, a second isolator 10, a third isolator 11, and a 1550nm wavelength 3 × 3 coupler 12.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The working principle of the invention is as follows:

the relative intensity noise amplitude of a fiber optic gyroscope is inversely proportional to the square root of the spectral width of the input light source and can be expressed as:

（1）

wherein the content of the first and second substances,σ _RIN for the amplitude of the noise of the correlation intensity, ΔvThe equivalent spectral width of the light source.

Example one

The present invention will be described in detail with reference to fig. 1.

As shown in fig. 1, a light source for a triaxial optical fiber gyroscope according to the present invention includes a 980nm pump laser 1, a 980nm wavelength 3 × 3 coupler 2, a first wavelength division multiplexer 3, a second wavelength division multiplexer 4, a third wavelength division multiplexer 5, a first erbium-doped fiber 6, a second erbium-doped fiber 7, a third erbium-doped fiber 8, a first isolator 9, a second isolator 10, a third isolator 11, and a 1550nm wavelength 3 × 3 coupler 12, which are connected by fiber fusion.

Wherein, a 980nm pump laser 1 is connected with a b port of a 980nm wavelength 3X 3 coupler 2,

the a and c ports of the 980nm wavelength 3X 3 coupler 2 are processed by fiber folding,

the d port of the 980nm wavelength 3 x 3 coupler 2 is connected to the b port of the first wavelength division multiplexer 3,

the e-port of the 980nm wavelength 3 x 3 coupler 2 is connected to the b-port of the second wavelength division multiplexer 4,

the f-port of the 980nm wavelength 3 x 3 coupler 2 is connected to the b-port of the third wavelength division multiplexer 5,

the c port of the first wavelength division multiplexer 3 is connected to the a port of the first erbium-doped fiber 6,

the port c of the second wavelength division multiplexer 4 is connected to the port a of the second erbium doped fiber 7,

the c port of the third wavelength division multiplexer 5 is connected to the a port of the third erbium doped fibre 8,

the b port of the first erbium-doped fiber 6 is processed by fiber folding or connected with a reflector,

the b port of the second erbium-doped fiber 7 is processed by fiber folding or connected with a reflector,

the b port of the third erbium-doped fiber 8 is processed by fiber folding or is connected with a reflector,

the a port of the first wavelength division multiplexer 3 is connected to the a port of the first isolator 9,

the a port of the second wavelength division multiplexer 4 is connected to the a port of the second isolator 10,

the a port of the third wavelength division multiplexer 5 is connected to the a port of the third isolator 11,

the b-port of the first isolator 9 is connected to the a-port of the 1550nm wavelength 3 x 3 coupler 12,

the b-port of the second isolator 10 is connected to the b-port of the 1550nm wavelength 3 x 3 coupler 12,

the b port of the third isolator 11 is connected to the c port of the 1550nm wavelength 3 x 3 coupler 12,

the d, e and f ports of the 1550nm wavelength 3 × 3 coupler 12 are used as three independent output light sources.

The invention adopts a 980nm wavelength 3X 3 coupler to realize that three sections of independent erbium-doped optical fibers share one 980nm pump laser, adopts a 1550nm wavelength 3X 3 coupler to divide the light waves output by the three sections of independent erbium-doped optical fibers into a plurality of light waves after traveling and wave-back, improves the integration level of a light source for the three-axis gyroscope, reduces the cost, improves the equivalent spectral width of an input light source of the optical fiber gyroscope to directly reduce the related intensity noise, and thus improves the precision of the optical fiber gyroscope.