Homologous homodyne self-coherent optical fiber communication and sensing integrated device and method

Abstract

The invention provides a homologous homodyne self-coherent optical fiber communication and sensing integrated device and method, and the method comprises the steps: a first transmitting end transmits first detection light and first communication light to a second communication receiving end through a first fiber core and a second fiber core of a multi-core optical fiber; the second communication receiving end performs homodyne self-correlation detection according to the first communication light and the first detection light; the second transmitting end transmits second detection light and second communication light to the first communication receiving end through a third fiber core and a fourth fiber core of the multi-core optical fiber respectively; the first communication receiving end performs homodyne self-correlation detection according to the second communication light and the second detection light; the first sensing receiving end and the second sensing end are respectively used for demodulating disturbance phases of the second detection light and the first detection light so as to obtain disturbance positions; the communication light and the detection light are transmitted through a plurality of fiber cores in the same optical fiber, so that external interference on the communication light and the detection light is consistent, and the communication demodulation performance and the sensing demodulation performance of homodyne self-correlation detection are improved.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technology, and in particular to a homologous homodyne self-coherent optical fiber communication and sensing integrated device and method. Background Art

[0002] At present, in most integrated optical fiber communication and sensing systems, the corresponding communication optical signals and local oscillator reference lights are usually transmitted using different optical fibers, resulting in different external interference effects on the communication optical signals and the local oscillator reference lights, resulting in relatively poor performance of zero-difference autocorrelation detection of the communication optical signals and the local oscillator reference lights, and further resulting in poor demodulation performance of the communication optical signals.

[0003] In view of this, overcoming the defects of the prior art is an urgent problem to be solved in the field of this technology. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to improve the demodulation performance of communication optical signals in optical fiber communication with integrated sensing.

[0005] The present invention adopts the following technical solution: In a first aspect, a homologous homodyne self-coherent optical fiber communication and sensing integrated device is provided, comprising: a first transmitting end, a first communication receiving end, a multi-core transmission optical fiber, a second transmitting end, and a second communication receiving end; The first transmitting end is used to send a first detection light to the second communication receiving end through the first core in the multi-core transmission optical fiber; and is also used to send a first communication light to the second communication receiving end through the second core in the multi-core transmission optical fiber; the second communication receiving end is used to perform homodyne autocorrelation detection based on the first communication light and the first detection light; wherein the first detection light and the first communication light are generated by the same laser; The second transmitting end is used to send a second detection light to the first communication receiving end through the third core in the multi-core transmission optical fiber; and is also used to send a second communication light to the first communication receiving end through the fourth core in the multi-core transmission optical fiber; the first communication receiving end is used to perform homodyne autocorrelation detection based on the second communication light and the second detection light; wherein the second detection light and the second communication light are generated by the same laser.

[0006] Preferably, it further comprises: a first sensor receiving end and a second sensor receiving end; The first sensor receiving end is used to receive the first reference light from the first transmitting end and the second detection light from the second transmitting end; the first sensor receiving end is used to perform phase demodulation according to the first reference light and the second detection light, so as to obtain the disturbed phase of the second detection light; The second sensor receiving end is used to receive the second reference light from the second transmitting end and the first detection light from the first transmitting end; the second sensor receiving end is used to perform phase demodulation according to the second reference light and the first detection light, so as to obtain the disturbed phase of the first detection light.

[0007] Preferably, the first transmitting end includes a first laser, a first coupler and a first modulator; The first laser is used to emit a first laser, and the first coupler is used to divide the first laser into three paths, the first path laser signal is used as the first reference light, and the second path laser signal is used as the first detection light; the third path laser signal is orthogonally IQ modulated by the first modulator and used as the first communication light; The second transmitting end includes a second laser, a second coupler and a second modulator; The second laser is used to emit a second laser, and the second coupler is used to divide the second laser into three paths, the first laser signal is used as the second reference light, the second laser signal is used as the second detection light; the third laser signal is orthogonally IQ modulated by the second modulator and used as the second communication light.

[0008] Preferably, it further comprises a third coupler and a fourth coupler; The third coupler is used to divide the first detection light into two paths, one of which is transmitted to the second communication receiving end, and the other is transmitted to the second sensing receiving end; The fourth coupler is used to divide the second detection light into two paths, wherein one path of the second detection light is transmitted to the first communication receiving end, and the other path of the second detection light is transmitted to the first sensing receiving end.

[0009] In a second aspect, a homologous homodyne self-coherent optical fiber communication and sensing integration method is provided, which is used for application in the homologous homodyne self-coherent optical fiber communication and sensing integration device, comprising: The first transmitting end sends a first detection light to the second communication receiving end through the first core in the multi-core transmission optical fiber; the first transmitting end also sends a first communication light to the second communication receiving end through the second core in the multi-core transmission optical fiber; the second communication receiving end performs homodyne autocorrelation detection based on the first communication light and the first detection light, thereby obtaining an I-path signal current and a Q-path signal current corresponding to the first communication light; The second transmitting end sends a second detection light to the first communication receiving end through the third fiber core in the multi-core transmission optical fiber; the second transmitting end also sends a second communication light to the first communication receiving end through the fourth fiber core in the multi-core transmission optical fiber; the first communication receiving end performs homodyne autocorrelation detection based on the second communication light and the second detection light, thereby obtaining the corresponding I-path signal current and Q-path signal current of the second communication light.

[0010] Preferably, the second communication receiving end performs homodyne autocorrelation detection according to the first communication light and the first detection light, thereby obtaining an I-path signal current and a Q-path signal current corresponding to the first communication light, specifically including: Acquire the phase and optical power of the first communication light through the second communication receiving end; The I-path signal current and the Q-path signal current corresponding to the first communication light are respectively acquired according to the phase of the first communication light, the optical power of the first communication light, and the optical power and phase of the first detection light.

[0011] Preferably, the second communication receiving end performs homodyne autocorrelation detection according to the first communication light and the first detection light, thereby obtaining an I-path signal current and a Q-path signal current corresponding to the first communication light, specifically including: The I-channel signal current corresponding to the first communication light The calculation formula is: ; The Q-path signal current corresponding to the first communication light The calculation formula is: ; where R is a coefficient related to the photodetector responsivity, coupler splitting ratio, fiber loss, and polarization and frequency mismatch, is the phase of the first communication light received by the second communication receiving end, It is the optical power obtained by square root of the product of the optical power of the first communication light and the optical power of the first detection light.

[0012] Preferably, the homologous homodyne self-coherent optical fiber communication and sensing integrated device further comprises a first sensing receiving end and a second sensing receiving end; the homologous homodyne self-coherent optical fiber communication and sensing integrated method further comprises: The first sensor receiving end receives the first reference light from the first transmitting end and the second detection light from the second transmitting end; the first sensor receiving end performs coherent detection phase demodulation according to the first reference light and the second detection light, thereby obtaining the disturbed phase of the second detection light; The second sensing receiving end receives the second reference light from the second transmitting end and the first detection light from the first transmitting end; the second sensing receiving end performs coherent detection phase demodulation according to the second reference light and the first detection light, thereby obtaining the disturbed phase of the first detection light; A disturbance position on the multi-core transmission optical fiber is acquired according to the disturbed phase of the second detection light and the disturbed phase of the first detection light.

[0013] Preferably, the first sensor receiving end performs coherent detection phase demodulation according to the first reference light and the second detection light to obtain the disturbed phase of the second detection light, specifically including: The calculation formula of the disturbed phase of the second detection light is: ; in, is the angular frequency of the laser emitted from the second emitting end, is the angular frequency of the laser emitted from the first emitting end, is the phase of the second detection light, , n is the core refractive index of the third fiber core, l is the length of the third fiber core, c is the speed of light in vacuum, is the phase of the first reference light output by the first transmitting end, is the phase noise, is the phase change caused by external disturbance, , is the transmission time of the optical signal from the disturbance position on the third fiber core to the first sensor receiving end, is the transmission distance of the optical signal from the disturbance position on the third fiber core to the first sensor receiving end.

[0014] Preferably, the second sensor receiving end performs coherent detection phase demodulation according to the second reference light and the first detection light to obtain the disturbed phase of the first detection light, specifically including: The calculation formula of the disturbed phase of the first detection light is: ; in, is the angular frequency of the laser emitted from the second emitting end, is the angular frequency of the laser emitted from the first emitting end, is the phase of the first detection light, , n is the core refractive index of the first core, l is the length of the first core, c is the speed of light in vacuum, is the phase of the second reference light output from the second transmitting end, is the phase noise, is the phase change caused by external disturbance, , is the transmission time of the optical signal from the disturbance position on the first fiber core to the second sensor receiving end, is the transmission distance of the optical signal from the disturbance position on the first fiber core to the second sensor receiving end.

[0015] The present invention provides a homologous homodyne self-coherent optical fiber communication and sensing integrated device and method, wherein a first transmitting end sends a first detection light to a second communication receiving end through a first fiber core in a multi-core transmission optical fiber, and is also used to send the first communication light to the second communication receiving end through a second fiber core in the multi-core transmission optical fiber; the second communication receiving end performs homodyne autocorrelation detection according to the first communication light and the first detection light; the second transmitting end sends a second detection light to the first communication receiving end through a third fiber core in the multi-core transmission optical fiber; and is also used to send a second communication light to the first communication receiving end through a fourth fiber core in the multi-core transmission optical fiber; the first communication receiving end performs homodyne autocorrelation detection according to the second communication light and the second detection light; the first sensing receiving end is used to demodulate the disturbance phase of the second detection light, and the second sensing receiving end is used to demodulate the disturbance phase of the first detection light; the communication light and the detection light are transmitted through multiple fiber cores in the same optical fiber, so that the external interferences to the communication light and the detection light are consistent, thereby improving the communication demodulation performance and the sensing demodulation performance of the homodyne autocorrelation detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 It is a structural schematic diagram of a homologous homodyne self-coherent optical fiber communication and sensing integrated device provided by an embodiment of the present invention; Figure 2 It is a method flow chart of a method for integrating homologous homodyne self-coherent optical fiber communication and sensing provided by an embodiment of the present invention; Figure 3 It is a flow chart of a demodulation method corresponding to the first communication light in a homologous homodyne self-coherent optical fiber communication and sensing integration method provided by an embodiment of the present invention; Figure 4 It is a flow chart of a demodulation method corresponding to the second communication light in a homologous homodyne self-coherent optical fiber communication and sensing integration method provided by an embodiment of the present invention; Figure 5It is a flow chart of a demodulation method for detecting the phase of sensing light and the position of optical fiber disturbance in a homologous homodyne self-coherent optical fiber communication and sensing integration method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] In the description of the present invention, it is necessary to understand that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present disclosure.

[0020] In the description of the present invention, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, the meaning of "multiple" is two or more. In addition, for example, the same type of nouns may be described as two independent individuals by adding "A" and "B" at the end. In this case, the corresponding features defined as "A" and "B" are only used to distinguish the same type of individuals for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features.

[0021] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity, i.e., the limitations of the measurement system.

[0022] Unless the context requires otherwise, throughout the specification and claims, the term "including" is to be interpreted as open inclusion, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "examples", "specific examples" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner, that is, although they may be carried in the embodiments or examples of the above terms due to reasons such as the order and position of appearance, it is not limited to that they can be carried in combination by one embodiment or example.

[0023] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] Embodiment 1: Embodiment 1 of the present invention provides a homodyne self-coherent optical fiber communication and sensing integrated device, such as Figure 1 As shown, it includes: a first transmitting end, a first communication receiving end, a multi-core transmission optical fiber, a second transmitting end and a second communication receiving end.

[0025] The first transmitting end is used to send a first detection light to the second communication receiving end through the first core in the multi-core transmission optical fiber; and is also used to send a first communication light to the second communication receiving end through the second core in the multi-core transmission optical fiber; the second communication receiving end is used to perform homodyne autocorrelation detection based on the first communication light and the first detection light; wherein the first detection light and the first communication light are generated by the same laser.

[0026] The second transmitting end is used to send a second detection light to the first communication receiving end through the third core in the multi-core transmission optical fiber; and is also used to send a second communication light to the first communication receiving end through the fourth core in the multi-core transmission optical fiber; the first communication receiving end is used to perform homodyne autocorrelation detection based on the second communication light and the second detection light; wherein the second detection light and the second communication light are generated by the same laser.

[0027] In this embodiment, the first transmitting end and the first communication receiving end are located at one end of the homologous homodyne self-coherent optical fiber communication and sensing integrated device, and the second transmitting end and the second communication receiving end are located at the other end of the homologous homodyne self-coherent optical fiber communication and sensing integrated device. The structures and configurations of the devices at the two ends are symmetrically arranged, and optical signals are transmitted to each other through the multi-core transmission optical fiber.

[0028] In this embodiment, narrow linewidth lasers are provided in the first transmitting end and the second transmitting end, and the first detection light and the second detection light can be used as local oscillator reference light. The second communication receiving end is used to perform homodyne autocorrelation detection with the first communication light using the first detection light as the local oscillator reference light, so as to obtain the I-path signal current and the Q-path signal current corresponding to the first communication light, and to implement signal demodulation of the first communication light according to the I-path signal current and the Q-path signal current corresponding to the first communication light. The first communication receiving end is used to perform homodyne autocorrelation detection with the second detection light as the local oscillator reference light, so as to obtain the I-path signal current and the Q-path signal current corresponding to the second communication light, and to implement signal demodulation of the second communication light according to the I-path signal current and the Q-path signal current corresponding to the second communication light.

[0029] In this embodiment, the first fiber core, the second fiber core, the third fiber core and the fourth fiber core are all located in the same multi-core transmission optical fiber, and the first fiber core, the second fiber core, the third fiber core and the fourth fiber core are all of the same model and have the same performance. In the present embodiment, the first detection light and the first communication light are emitted by the same laser in the first transmitting end and are transmitted from the same multi-core transmission optical fiber. Therefore, the parameter performance of the first communication light and the first detection light received by the second communication receiving end and the external interference they receive are basically completely consistent. Similarly, the second detection light and the second communication light are emitted by the same laser in the second transmitting end and are transmitted from the same multi-core transmission optical fiber. Therefore, the parameter performance of the second communication light and the second detection light received by the first communication receiving end and the external interference they receive are basically completely consistent. Compared with the existing method of using different lasers to respectively emit communication light signals and detection light, and transmitting them with different optical fibers at the same time, the two optical fibers are often located in very different positions and environments, resulting in a relatively large difference in the disturbances received by the optical signals transmitted in the two optical fibers, and thus the performance of the homodyne autocorrelation detection performed by the communication receiving end is relatively poor. Therefore, the present embodiment ensures that the performance of the homodyne autocorrelation detection performed by the first communication receiving end and the second communication receiving end is better.

[0030] Furthermore, in the prior art, backscattered Rayleigh light signals are usually generated in optical fibers for sensing, but the backscattered Rayleigh light signals are essentially caused by the Rayleigh scattering of optical signals in optical fibers, and have a relatively weak intensity, and cannot be transmitted over long distances. Even if the sensor receiving end can receive the backscattered Rayleigh light signals, the signal intensity of the backscattered Rayleigh light signals is also very weak, which is not conducive to subsequent calculations. Therefore, this embodiment also involves the following designs: The homologous homodyne self-coherent optical fiber communication and sensing integrated device also includes: a first sensing receiving end and a second sensing receiving end; the first sensing receiving end is used to receive a first reference light from the first transmitting end and a second detection light from the second transmitting end; the first sensing receiving end is used to perform phase demodulation according to the first reference light and the second detection light, so as to obtain the disturbed phase of the second detection light; the second sensing receiving end is used to receive the second reference light from the second transmitting end and the first detection light from the first transmitting end; the second sensing receiving end is used to perform phase demodulation according to the second reference light and the first detection light, so as to obtain the disturbed phase of the first detection light.

[0031] In this embodiment, the position where the disturbance occurs in the multi-core transmission optical fiber is obtained by acquiring the disturbed phase of the first detection light and the disturbed phase of the second detection light.

[0032] In this embodiment, the first detection light is directly emitted from the first transmitting end, and the second detection light is directly emitted from the second transmitting end. Therefore, the optical signal intensities of the first detection light and the second detection light are relatively stronger, and effective transmission over longer distances can be performed, which can greatly improve the detection distance of distributed optical fiber sensing.

[0033] Further, in this embodiment, the first transmitting end intends to realize the transmission of corresponding optical signals for the first fiber core, the second fiber core and the first sensor receiving end, and the second transmitting end intends to realize the transmission of corresponding optical signals for the third fiber core, the fourth fiber core and the second sensor receiving end. This embodiment also involves the following design: like Figure 1 As shown, the first transmitting end includes a first laser, a first coupler and a first modulator; the first laser is used to emit a first laser, and the first coupler is used to divide the first laser into three paths, the first laser signal is used as the first reference light, and the second laser signal is used as the first detection light; the third laser signal is orthogonally IQ modulated by the first modulator and used as the first communication light.

[0034] The second transmitting end includes a second laser, a second coupler and a second modulator; the second laser is used to emit a second laser, and the second coupler is used to divide the second laser into three paths, the first laser signal is used as the second reference light, and the second laser signal is used as the second detection light; the third laser signal is orthogonally IQ modulated by the second modulator and used as the second communication light.

[0035] In this embodiment, the angular frequency generated by the first laser is The narrow line width laser generated by the first laser can be expressed as: ; in, is the phase of the narrow linewidth laser, is the optical power of the laser emitted by the first laser in the first emitting end.

[0036] The first laser is divided into three paths through the first coupler; the first path can separate 60±5% of the first laser as the first detection light, and send the first detection light to the second communication receiving end and the second sensor receiving end through the first fiber core; the second path can separate 20±5% of the first laser and be orthogonally IQ modulated by the first modulator into the first communication light, and sent to the second communication receiving end of the opposite end through the second fiber core; the third path can separate 20±5% of the first laser and use it as the first reference light, and send the first reference light to the first sensor receiving end of this end.

[0037] In this embodiment, the angular frequency generated by the second laser is The narrow line width laser generated by the second laser can be expressed as: ; in, is the phase of the narrow linewidth laser, is the optical power of the laser emitted by the second laser in the second emitting end.

[0038] The second laser is divided into three paths through the second coupler; the first path can separate 60±5% of the second laser as the second detection light, and send the second detection light to the first communication receiving end and the first sensing receiving end through the third fiber core; the second path can separate 20±5% of the second laser and be modulated into the second communication light by the second modulator, and sent to the first communication receiving end of the opposite end through the fourth fiber core; the third path can separate 20±5% of the second laser and use it as the second reference light, and send the second reference light to the second sensing receiving end of this end.

[0039] Furthermore, since the first fiber core also needs to be connected to the second sensing receiving end and the second communication receiving end, so as to transmit the first detection light to the second communication receiving end and the second sensing receiving end respectively, the third fiber core also needs to be connected to the first sensing receiving end and the first communication receiving end, so as to transmit the second detection light to the first communication receiving end and the first sensing receiving end respectively, this embodiment also involves the following design: like Figure 1As shown, the homologous homodyne self-coherent optical fiber communication and sensing integrated device also includes a third coupler and a fourth coupler; the third coupler is used to divide the first detection light into two paths, one of which is transmitted to the second communication receiving end, and the other is transmitted to the second sensing receiving end; the fourth coupler is used to divide the second detection light into two paths, one of which is transmitted to the first communication receiving end, and the other is transmitted to the first sensing receiving end.

[0040] In this embodiment, the first detection light is divided into two paths by the third coupler: one path is used to separate 80±5% of the first detection light for input into the second communication receiving end as the local oscillator reference light, and is used to perform zero-difference autocorrelation detection with the first communication light to achieve demodulation of the first communication light; the other path is used to separate 20±5% of the first detection light for input into the second sensor receiving end as the detection sensing light, and is used to perform coherent detection and phase demodulation with the second reference light to obtain the disturbance position on the multi-core transmission optical fiber.

[0041] The second detection light is divided into two paths by the fourth coupler: one path is used to divide 80±5% of the second detection light for inputting into the first communication receiving end as the local oscillator reference light, and is used to perform zero-difference autocorrelation detection with the second communication light to achieve demodulation of the second communication light; the other path is used to divide 20±5% of the second detection light for inputting into the first sensing receiving end as the detection sensing light, and is used to perform coherent detection and phase demodulation with the first reference light to obtain the disturbance position on the multi-core transmission optical fiber.

[0042] In this embodiment, for the homodyne autocorrelation detection performed by the second communication receiving end, the corresponding calculation method is as follows: The I-path signal current and the Q-path signal current in the first communication light are respectively acquired according to the phase of the first communication light, the optical power of the first communication light, and the optical power and phase of the first detection light.

[0043] The I-channel signal current in the first communication light The calculation formula is: ; The Q-path signal current in the first communication light The calculation formula is: ; where R is a coefficient related to the photodetector responsivity, coupler splitting ratio, fiber loss, and polarization and frequency mismatch, is the phase of the first communication light received by the second communication receiving end, It is the optical power obtained by square root of the product of the optical power of the first communication light and the optical power of the first detection light.

[0044] In this embodiment, for the homodyne autocorrelation detection performed by the first communication receiving end, the corresponding calculation method is as follows: The I-path signal current and the Q-path signal current in the second communication light are respectively acquired according to the phase of the second communication light, the optical power of the second communication light, and the optical power and phase of the second detection light.

[0045] The I-channel signal current in the second communication light The calculation formula is: ; The Q-path signal current in the second communication light The calculation formula is: ; where R is a coefficient related to the photodetector responsivity, coupler splitting ratio, fiber loss, and polarization and frequency mismatch, is the phase of the second communication light received by the first communication receiving end, The optical power is the square root of the product of the optical power of the second communication light and the optical power of the second detection light.

[0046] In this embodiment, for the phase demodulation performed by the second sensor receiving end, the corresponding calculation method is as follows: The calculation formula of the disturbed phase of the first detection light is: ; in, is the angular frequency of the laser emitted from the second emitting end, is the angular frequency of the laser emitted from the first emitting end, is the phase of the first detection light, , n is the core refractive index of the first core, l is the length of the first core, c is the speed of light in vacuum, is the phase of the second reference light output by the second laser, is the phase noise, is the phase change caused by external disturbance, , is the transmission time of the optical signal from the optical fiber disturbance position on the first fiber core to the second sensor receiving end, is the transmission distance of the optical signal from the optical fiber disturbance position on the first fiber core to the second sensor receiving end.

[0047] In this embodiment, for the phase demodulation performed by the first sensor receiving end, the corresponding calculation method is as follows: The calculation formula of the disturbed phase of the second detection light is: ; in, is the angular frequency of the laser emitted from the second emitting end, is the angular frequency of the laser emitted from the first emitting end, is the phase of the second detection light, , n is the core refractive index of the third fiber core, l is the length of the third fiber core, c is the speed of light in vacuum, is the phase of the first reference light output by the first laser, is the phase noise, is the phase change caused by external disturbance, , is the transmission time of the optical signal from the optical fiber disturbance position on the third fiber core to the first sensor receiving end, is the transmission distance of the optical signal from the optical fiber disturbance position on the third fiber core to the first sensor receiving end.

[0048] Embodiment 2: Based on Example 1, this embodiment provides a homologous homodyne self-coherent optical fiber communication and sensing integration method, which is used in the homologous homodyne self-coherent optical fiber communication and sensing integration device described in Example 1, such as Figure 2 As shown, including: In step 101, the first transmitting end sends a first detection light to the second communication receiving end through the first core in the multi-core transmission optical fiber; the first transmitting end also sends a first communication light to the second communication receiving end through the second core in the multi-core transmission optical fiber; the second communication receiving end performs homodyne autocorrelation detection based on the first communication light and the first detection light, thereby obtaining the corresponding current of the first communication light.

[0049] In step 102, the second transmitting end sends a second detection light to the first communication receiving end through the third core in the multi-core transmission optical fiber; the second transmitting end also sends a second communication light to the first communication receiving end through the fourth core in the multi-core transmission optical fiber; the first communication receiving end performs homodyne autocorrelation detection based on the second communication light and the second detection light, thereby obtaining the corresponding current of the second communication light.

[0050] Further, the second communication receiving end performs homodyne autocorrelation detection according to the first communication light and the first detection light, thereby obtaining the current corresponding to the first communication light, such as Figure 3 As shown, the method flow includes: In step 201, the phase and optical power of the first communication light are obtained through the second communication receiving end.

[0051] In step 202, an I-path signal current and a Q-path signal current corresponding to an I communication light signal in the first communication light are respectively obtained according to the phase of the first communication light, the optical power of the first communication light, and the optical power and phase of the first detection light.

[0052] The I-channel signal current in the communication optical signal The calculation formula is: ; The Q-path signal current in the communication optical signal The calculation formula is: ; where R is a coefficient related to the photodetector responsivity, coupler splitting ratio, fiber loss, and polarization and frequency mismatch, is the phase of the communication optical signal received by the communication receiving end 2 at the other end, It is the optical power obtained by square root of the product of the optical power of the first communication light and the optical power of the first detection light.

[0053] The first communication receiving end performs homodyne autocorrelation detection according to the second communication light and the second detection light, thereby obtaining a current corresponding to the second communication light, such as Figure 4 As shown, the method flow includes: In step 301, the phase and optical power of the second communication light are obtained through the first communication receiving end.

[0054] In step 302, an I-path signal current and a Q-path signal current in the second communication light are respectively acquired according to the phase of the second communication light, the optical power of the second communication light, and the optical power and phase of the second detection light.

[0055] The I-channel signal current in the second communication light The calculation formula is: ; The Q-path signal current in the second communication light The calculation formula is: ; where R is a coefficient related to the photodetector responsivity, coupler splitting ratio, fiber loss, and polarization and frequency mismatch, is the phase of the second communication light received by the first communication receiving end, The optical power is the square root of the product of the optical power of the second communication light and the optical power of the second detection light.

[0056] Furthermore, the homodyne self-coherent optical fiber communication and sensing integrated device further comprises a first sensing receiving end and a second sensing receiving end, correspondingly, as Figure 5 As shown, the demodulation method of the sensing light signal of the first sensing receiving end and the second sensing receiving end is: In step 401, the first sensor receiving end receives the first reference light from the first transmitting end and the second detection light from the second transmitting end; the first sensor receiving end performs coherent detection phase demodulation according to the first reference light and the second detection light, thereby obtaining the disturbed phase of the second detection light.

[0057] In step 402, the second sensor receiving end receives the second reference light from the second transmitting end and the first detection light from the first transmitting end; the second sensor receiving end performs coherent detection phase demodulation based on the second reference light and the first detection light, thereby obtaining the disturbed phase of the first detection light.

[0058] In step 403, a disturbance position on the multi-core transmission optical fiber is acquired according to the disturbed phase of the second detection light and the disturbed phase of the first detection light.

[0059] In this embodiment, for the coherent detection phase demodulation performed by the second sensor receiving end, the corresponding calculation method is as follows: The calculation formula of the disturbed phase of the first detection light is: ; in, is the angular frequency of the laser emitted from the second emitting end, is the angular frequency of the laser emitted from the first emitting end, is the phase of the first detection light, , n is the core refractive index of the first core, l is the length of the first core, c is the speed of light in vacuum, is the phase of the second reference light output by the second laser, is the phase noise, is the phase change caused by external disturbance, , is the transmission time of the optical signal from the optical fiber disturbance position on the first fiber core to the second sensor receiving end, is the transmission distance of the optical signal from the optical fiber disturbance position on the first fiber core to the second sensor receiving end.

[0060] In this embodiment, for the coherent detection phase demodulation performed by the first sensor receiving end, the corresponding calculation method is as follows: The calculation formula of the disturbed phase of the second detection light is: ; in, is the angular frequency of the laser emitted from the second emitting end, is the angular frequency of the laser emitted from the first emitting end, is the phase of the second detection light, , n is the core refractive index of the third fiber core, l is the length of the third fiber core, c is the speed of light in vacuum, is the phase of the first reference light output by the first laser, is the phase noise, is the phase change caused by external disturbance, , is the transmission time of the optical signal from the optical fiber disturbance position on the third fiber core to the first sensor receiving end, is the transmission distance of the optical signal from the optical fiber disturbance position on the third fiber core to the first sensor receiving end.

[0061] In this embodiment, obtaining the disturbance position on the multi-core transmission optical fiber according to the disturbed phase of the second detection light and the disturbed phase of the first detection light specifically includes: For the obtained as well as Perform filtering operation and Approximately ,Will Approximately ,right as well as Perform cross-correlation, There is a peak at , l is the length of the third fiber core, so the external disturbance position is based on or The disturbance position on the multi-core transmission optical fiber is obtained.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A homodyne self-coherent optical fiber communication and sensing integrated device, characterized in that: include: A first transmitting end, a first communication receiving end, a multi-core transmission optical fiber, a second transmitting end, and a second communication receiving end; The first transmitting end is used to send a first detection light to the second communication receiving end through the first core in the multi-core transmission optical fiber; and is also used to send a first communication light to the second communication receiving end through the second core in the multi-core transmission optical fiber; the second communication receiving end is used to perform homodyne autocorrelation detection based on the first communication light and the first detection light; wherein the first detection light and the first communication light are generated by the same laser; The second transmitting end is used to send a second detection light to the first communication receiving end through the third core in the multi-core transmission optical fiber; and is also used to send a second communication light to the first communication receiving end through the fourth core in the multi-core transmission optical fiber; the first communication receiving end is used to perform homodyne autocorrelation detection based on the second communication light and the second detection light; wherein the second detection light and the second communication light are generated by the same laser.

2. The homodyne self-coherent optical fiber communication and sensing integrated device according to claim 1, characterized in that: Also includes: A first sensor receiving end and a second sensor receiving end; The first sensor receiving end is used to receive the first reference light from the first transmitting end and the second detection light from the second transmitting end; The first sensor receiving end is used to perform phase demodulation according to the first reference light and the second detection light, so as to obtain the disturbed phase of the second detection light; The second sensor receiving end is used to receive the second reference light from the second transmitting end and the first detection light from the first transmitting end; the second sensor receiving end is used to perform phase demodulation according to the second reference light and the first detection light, so as to obtain the disturbed phase of the first detection light.

3. The homodyne self-coherent optical fiber communication and sensing integrated device according to claim 2, characterized in that: The first transmitting end includes a first laser, a first coupler and a first modulator; The first laser is used to emit a first laser, and the first coupler is used to divide the first laser into three paths, the first path laser signal is used as the first reference light, and the second path laser signal is used as the first detection light; the third path laser signal is orthogonally IQ modulated by the first modulator and used as the first communication light; The second transmitting end includes a second laser, a second coupler and a second modulator; The second laser is used to emit a second laser, and the second coupler is used to divide the second laser into three paths, the first laser signal is used as the second reference light, the second laser signal is used as the second detection light; the third laser signal is orthogonally IQ modulated by the second modulator and used as the second communication light.

4. The homodyne self-coherent optical fiber communication and sensing integrated device according to claim 2, characterized in that: Also comprising a third coupler and a fourth coupler; The third coupler is used to divide the first detection light into two paths, one of which is transmitted to the second communication receiving end, and the other is transmitted to the second sensing receiving end; The fourth coupler is used to divide the second detection light into two paths, wherein one path of the second detection light is transmitted to the first communication receiving end, and the other path of the second detection light is transmitted to the first sensing receiving end.

5. A homologous homodyne self-coherent optical fiber communication and sensing integration method, used for application in the homologous homodyne self-coherent optical fiber communication and sensing integration device as described in any one of claims 1 to 4, characterized in that: include: The first transmitting end sends a first detection light to the second communication receiving end through the first fiber core in the multi-core transmission optical fiber; The first transmitting end also sends the first communication light to the second communication receiving end through the second fiber core in the multi-core transmission optical fiber; the second communication receiving end performs homodyne autocorrelation detection according to the first communication light and the first detection light, thereby obtaining the corresponding I-path signal current and Q-path signal current of the first communication light; The second transmitting end sends a second detection light to the first communication receiving end through the third fiber core in the multi-core transmission optical fiber; the second transmitting end also sends a second communication light to the first communication receiving end through the fourth fiber core in the multi-core transmission optical fiber; the first communication receiving end performs homodyne autocorrelation detection based on the second communication light and the second detection light, thereby obtaining the corresponding I-path signal current and Q-path signal current of the second communication light.

6. The method for integrating homodyne self-coherent optical fiber communication and sensing according to claim 5, characterized in that: The second communication receiving end performs homodyne autocorrelation detection according to the first communication light and the first detection light, thereby obtaining an I-path signal current and a Q-path signal current corresponding to the first communication light, specifically including: Acquire the phase and optical power of the first communication light through the second communication receiving end; The I-path signal current and the Q-path signal current in the first communication light are respectively acquired according to the phase of the first communication light, the optical power of the first communication light, and the optical power and phase of the first detection light.

7. The method for integrating homodyne self-coherent optical fiber communication and sensing according to claim 6, characterized in that: The second communication receiving end performs homodyne autocorrelation detection according to the first communication light and the first detection light, thereby obtaining an I-path signal current and a Q-path signal current corresponding to the first communication light, specifically including: The I-channel signal current corresponding to the first communication light The calculation formula is: ； The Q-path signal current corresponding to the first communication light The calculation formula is: ； where R is a coefficient related to the photodetector responsivity, coupler splitting ratio, fiber loss, and polarization and frequency mismatch, is the phase of the first communication light received by the second communication receiving end, It is the optical power obtained by square root of the product of the optical power of the first communication light and the optical power of the first detection light.

8. The method for integrating homodyne self-coherent optical fiber communication and sensing according to claim 5, characterized in that: The homologous homodyne self-coherent optical fiber communication and sensing integrated device also includes a first sensing receiving end and a second sensing receiving end; The homologous homodyne self-coherent optical fiber communication and sensing integration method also includes: The first sensor receiving end receives the first reference light from the first transmitting end and the second detection light from the second transmitting end; the first sensor receiving end performs coherent detection phase demodulation according to the first reference light and the second detection light, thereby obtaining the disturbed phase of the second detection light; The second sensing receiving end receives the second reference light from the second transmitting end and the first detection light from the first transmitting end; the second sensing receiving end performs coherent detection phase demodulation according to the second reference light and the first detection light, thereby obtaining the disturbed phase of the first detection light; A disturbance position on the multi-core transmission optical fiber is acquired according to the disturbed phase of the second detection light and the disturbed phase of the first detection light.

9. The method for integrating homodyne self-coherent optical fiber communication and sensing according to claim 8, characterized in that: The first sensor receiving end performs coherent detection phase demodulation according to the first reference light and the second detection light to obtain the disturbed phase of the second detection light, specifically including: The calculation formula of the disturbed phase of the second detection light is: ； in, is the angular frequency of the laser emitted from the second emitting end, is the angular frequency of the laser emitted from the first emitting end, is the phase of the second detection light, , n is the core refractive index of the third fiber core, l is the length of the third fiber core, c is the speed of light in vacuum, is the phase of the first reference light output by the first transmitting end, is the phase noise, is the phase change caused by external disturbance, , is the transmission time of the optical signal from the disturbance position on the third fiber core to the first sensor receiving end, is the transmission distance of the optical signal from the disturbance position on the third fiber core to the first sensor receiving end.

10. The method for integrating homodyne self-coherent optical fiber communication and sensing according to claim 8, characterized in that: The second sensing receiving end performs coherent detection phase demodulation according to the second reference light and the first detection light to obtain the disturbed phase of the first detection light, specifically including: The calculation formula of the disturbed phase of the first detection light is: ； in, is the angular frequency of the laser emitted from the second emitting end, is the angular frequency of the laser emitted from the first emitting end, is the phase of the first detection light, , n is the core refractive index of the first core, l is the length of the first core, c is the speed of light in vacuum, is the phase of the second reference light output from the second transmitting end, is the phase noise, is the phase change caused by external disturbance, , is the transmission time of the optical signal from the disturbance position on the first fiber core to the second sensor receiving end, is the transmission distance of the optical signal from the disturbance position on the first fiber core to the second sensor receiving end.

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