Pulse light scrambling system and operation method thereof

Abstract

The invention provides a pulsed light scrambling system and an operation method thereof, and the system comprises an electro-optical modulator which is used for modulating continuous light to be modulated into a pulsed light signal; the passive scrambler is used for scrambling the pulse optical signal to obtain a scrambled pulse optical signal; the semiconductor optical amplifier is used for intercepting a target pulse signal from the scrambled pulse optical signal and inputting the target pulse signal into the optical fiber to be measured; the target pulse signal is aligned with the rear end of the scrambled optical pulse; the pulse optical signal period output by the SOA is determined based on the length of the optical fiber to be measured, and the ratio of the pulse optical signal period output by the SOA to the scrambled pulse optical signal period is an integer. According to the system, the pulse light scrambling implementation efficiency is improved, the system size and cost are optimized, and it is guaranteed that the system has the high-performance advantages of being high in pulse extinction ratio, steep in rising edge and free of frequency shift.

Description

Technical Field

[0001] The present invention relates to the field of distributed optical fiber sensing technology, and in particular to a pulse light scrambling system and an operating method thereof. Background Art

[0002] The mainstream distributed fiber optic sensing technology is to connect the signal transceiver to one end of the optical fiber. The signal transceiver sends light pulses to the optical fiber, and collects and analyzes the backscattered signals generated by the light pulses along the optical fiber to determine abnormal events along the optical fiber. Among them, the systems based on Brillouin scattering for sensing include the Brillouin optical time domain analyzer (BOTDA) system based on stimulated Brillouin scattering and the Brillouin optical time domain reflectometer (BOTDR) system based on spontaneous Brillouin scattering, which have the characteristics of being able to measure temperature and strain changes over a large dynamic range.

[0003] BOTDR and BOTDA systems need to inject pulsed light into the optical fiber to stimulate Brillouin scattering. In order to achieve high performance, one of the key requirements is to generate an optical pulse signal with an extinction ratio higher than 55dB, a rising edge less than 1ns and no frequency offset. In both systems, the quality of the optical pulse directly affects the accurate extraction of temperature or strain information and the optimization of sensing performance. On the premise that the quality of the optical pulse is guaranteed, in order to reduce the impact of polarization fading noise on the system, the optical pulse needs to be scrambled. Existing scrambling technologies are divided into two categories: active scrambling and passive scrambling. Active scrambling uses voltage to drive the crystal to actively disrupt the polarization state of light, so that the polarization state of the optical signal changes randomly over time. Passive scrambling relies on passive devices and realizes random changes in the polarization state of the optical signal through a specific optical structure. The mechanism of passive scrambling determines that it can only be used to scramble continuous light.

[0004] In the related art, the schemes for realizing optical pulse scrambling include the following: (1) passive polarization scrambler / active polarization scrambler + SOA (Semiconductor Optical Amplifier), (2) SOA + active polarization scrambler, (3) SOA + EOM (Electro-Optic Modulator) + active polarization scrambler, (4) EOM + EOM + active polarization scrambler and (5) EOM + EOM + polarization switch. The above schemes have the problems of large size, high cost and high power consumption. At the same time, the switching time of the polarization switch is too long, resulting in the inability to balance the measurement speed and robustness of the system. Summary of the invention

[0005] The present invention provides a pulse light scrambling system and an operating method thereof, so as to solve the defects of existing light pulse scrambling solutions, such as large system volume, high cost, high power consumption, inefficient system measurement or poor robustness, thereby improving the efficiency of pulse light scrambling and optimizing the system volume and cost.

[0006] The present invention provides a pulse light polarization scrambling system, comprising: An electro-optic modulator EOM, wherein the electro-optic modulator is used to modulate the continuous light to be modulated into a pulse light signal; A passive polarization scrambler, wherein the ratio of the signal transmission delay time of the passive polarization scrambler to the pulse modulation period of the electro-optical modulator is an integer; the passive polarization scrambler is used to scramble the pulse light signal to obtain a scrambled pulse light signal; the scrambled pulse light signal has the same pulse period as the pulse light signal; A semiconductor optical amplifier SOA, wherein the SOA is connected to the passive polarization scrambler via an optical fiber; the ratio of the period of the pulse signal output by the SOA to the period of the pulse light signal is an integer, and the period of the pulse signal output by the SOA is determined based on the length of the optical fiber to be tested; the SOA is used to intercept a target pulse signal from the scrambled pulse light signal and input the target pulse signal into the optical fiber to be tested; the target pulse signal is aligned with the rear end of the scrambled optical pulse.

[0007] According to a pulse light polarization scrambling system provided by the present invention, the passive polarization scrambler comprises: A polarization beam splitter PBS, wherein the PBS is connected to the EOM via an optical fiber; the PBS is used to split the pulse light signal into vertically polarized pulse light and parallel polarized pulse light; A polarization beam combiner PBC, wherein the PBC is connected to the PBS via two polarization-maintaining optical fibers, wherein the first polarization-maintaining optical fiber is used to transmit the parallel polarized pulsed light, and the second polarization-maintaining optical fiber is used to transmit the vertically polarized pulsed light; the PBC is used to synthesize the vertically polarized pulsed light and the parallel polarized pulsed light to obtain the scrambled pulsed light signal.

[0008] According to a pulse light polarization scrambling system provided by the present invention, the optical fiber between the PBS and the EOM is fused at 45 degrees.

[0009] According to a pulse light polarization scrambling system provided by the present invention, the length of the second polarization-maintaining optical fiber is greater than the length of the first polarization-maintaining optical fiber, and the length of the second polarization-maintaining optical fiber is greater than the coherence length of the light source; the light source is used to emit the continuous light to be modulated; The delay time of the passive polarization scrambler transmitting the signal through the first polarization-maintaining optical fiber and the second polarization-maintaining optical fiber and the length of each optical fiber have the following relationship: ; in, is the length of the first polarization-maintaining optical fiber, is the length of the second polarization-maintaining fiber, is the refractive index of the optical fiber, and c is the speed of light in a vacuum.

[0010] According to a pulse light scrambling system provided by the present invention, the pulse signal period output by the SOA is determined based on the following formula: ; in, T is the pulse signal period output by the SOA, L is the length of the optical fiber to be tested, is the refractive index of the optical fiber, c is the speed of light in a vacuum.

[0011] The present invention also provides an operating method of a pulse light scrambling system, comprising: The continuous light to be modulated is modulated into a pulsed light signal based on an electro-optical modulator (EOM); The pulse light signal is scrambled based on a passive polarization scrambler to obtain a scrambled pulse light signal; the ratio of the signal transmission delay time of the passive polarization scrambler to the pulse modulation period of the electro-optical modulator is an integer; the scrambled pulse light signal and the pulse light signal have the same pulse period; A target pulse signal is intercepted from the scrambled pulse light signal based on a semiconductor optical amplifier SOA, and the target pulse signal is input into the optical fiber to be tested; the target pulse signal is aligned with the rear end of the scrambled optical pulse; the SOA is connected to the passive polarization scrambler through an optical fiber; the ratio of the pulse light signal period output by the SOA to the period of the scrambled pulse light signal is an integer, and the pulse light signal period output by the SOA is determined based on the length of the optical fiber to be tested.

[0012] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, an operating method of the pulse light scrambling system as described above is implemented.

[0013] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the operating method of the pulse light scrambling system as described in any one of the above is implemented.

[0014] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements the operating method of any of the pulse light scrambling systems described above.

[0015] The pulse light scrambling system and operation method provided by the present invention modulate the continuous light to be modulated into a pulse light signal through an electro-optic modulator, set the ratio of the signal transmission delay time of a passive scrambler and the pulse modulation period of the electro-optic modulator to an integer, so as to realize the scrambling of the pulse light signal and obtain a scrambled pulse light signal, finally intercept the target pulse signal aligned with the rear end of the scrambled light pulse from the scrambled pulse light signal through an SOA, and output the target pulse signal through the optical fiber to be tested, thereby improving the efficiency of pulse light scrambling, optimizing the system volume and cost, and ensuring that the system has the high performance advantages of high pulse extinction ratio, steep rising edge and no frequency shift. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0017] Figure 1 It is a schematic structural diagram of the pulse light scrambling system provided by the present invention.

[0018] Figure 2 It is a schematic diagram of the principle of the SOA provided by the present invention intercepting a pulse light signal.

[0019] Figure 3 It is a schematic diagram of the principle of pulse light signal scrambling provided by the present invention.

[0020] Figure 4 The present invention is a schematic diagram of a process for implementing pulse light polarization scrambling by the passive polarization scrambler provided by the present invention.

[0021] Figure 5 It is a flow chart of the operation method of the pulse light scrambling system provided by the present invention.

[0022] Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention.

[0023] Reference numerals: 110: Electro-optic modulator EOM; 120: Passive polarization scrambler; 121: polarization beam splitter PBS; 122: polarization beam combiner PBC; 130: Semiconductor optical amplifier SOA. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Combine the following Figure 1-Figure 5 The pulse light scrambling system and its operation method of the present invention are described.

[0026] Figure 1 Schematic diagram of the structure of the pulse light scrambling system provided by the present invention. Figure 1 As shown, the pulse light polarization scrambling system includes: an electro-optic modulator EOM110, a passive polarization scrambler 120 and a semiconductor optical amplifier SOA130.

[0027] The electro-optic modulator is used to modulate the continuous light to be modulated into a pulsed light signal.

[0028] In this embodiment, the EOM 110 can output an optical pulse with a rising edge of less than 1 ns by modulating continuous light and has an extinction ratio of about 25 dB.

[0029] In this embodiment, light emitted by a light source (such as a laser) enters the EOM 110 through a polarization-maintaining optical fiber, and the EOM 110 modulates the continuous light into a period of Pulse light signal.

[0030] The ratio of the signal transmission delay time of the passive polarization scrambler 120 to the pulse modulation period of the electro-optic modulator is an integer; the passive polarization scrambler 120 is used to scramble the pulse light signal to obtain a scrambled pulse light signal; the scrambled pulse light signal has the same pulse period as the pulse light signal output by the EOM110.

[0031] In this embodiment, the period of the pulse light obtained by the passive polarization scrambling device 120 is determined by the delay time Determined; Furthermore, the passive polarization scrambler 120 includes: a polarization beam splitter PBS121, PBS121 is connected to EOM110 via an optical fiber; PBS121 is used to split the pulse light signal into vertically polarized pulse light and parallel polarized pulse light; a polarization beam combiner PBC122, PBC122 is connected to PBS121 via two polarization-maintaining optical fibers, the first polarization-maintaining optical fiber is used to transmit parallel polarized pulse light, and the second polarization-maintaining optical fiber is used to transmit vertically polarized pulse light; PBC122 is used to synthesize the vertically polarized pulse light and the parallel polarized pulse light to obtain a scrambled pulse light signal.

[0032] In this embodiment, the PBS 121 is connected to the EOM 110 via a polarization-maintaining optical fiber; the PBS 121 is used to split the pulse light signal into vertically polarized pulse light and parallel polarized pulse light.

[0033] Specifically, the optical fiber between the EOM 110 and the PBS 121 is fused at a certain angle, so that the pulse light is divided into polarized pulse light in a parallel direction and polarized pulse light in a vertical direction after passing through the PBS 121 .

[0034] Furthermore, the optical fiber between PBS 121 and EOM 110 is fused at 45 degrees.

[0035] In this embodiment, the optical fiber between the EOM 110 and the PBS 121 is fused at 45 degrees, so that the pulse light is divided into two pulse lights of parallel polarization and vertical polarization after passing through the PBS 121, and the power of the two pulse lights is consistent.

[0036] Polarization beam combiner PBC122, PBC122 and PBS121 are connected by two optical fibers, the first polarization-maintaining optical fiber is used to transmit parallel polarized pulse light, and the second polarization-maintaining optical fiber is used to transmit vertically polarized pulse light; PBC122 is used to synthesize the vertically polarized pulse light and the parallel polarized pulse light to obtain a scrambled pulse light signal, and the scrambled pulse light signal and the pulse light signal have the same pulse period.

[0037] In this embodiment, PBC122 is used to synthesize two pulse optical signals into an optical pulse signal with a random polarization state. If the signal transmission delay time between the first polarization-maintaining optical fiber and the second polarization-maintaining optical fiber is Equal to the pulse period of the input passive polarization scrambler 120 The pulse light transmitted by the second polarization-maintaining optical fiber will be synthesized at the same time as a pulse transmitted by the first polarization-maintaining optical fiber after being transmitted by the delayed optical fiber. Then, the subsequent pulse lights of the first polarization-maintaining optical fiber and the second polarization-maintaining optical fiber will be synthesized in PBC122 in turn, and the passive polarization scrambler 120 can output scrambled pulse light with the same period as the pulse light signal.

[0038] The pulse light polarization scrambling system provided in the embodiment of the present invention forms a passive polarization scrambler by setting a polarization beam splitter PBS, a polarization beam combiner PBC and a polarization-maintaining optical fiber connecting the PBS and the PBC, and realizes polarization scrambling of the pulse light by coordinating the EOM pulse modulation period and the delay time of the passive polarization scrambler.

[0039] SOA130 is connected to the passive scrambler 120 via an optical fiber; the ratio of the period of the pulse signal output by SOA130 to the period of the pulse light signal is an integer, and the period of the pulse signal output by SOA130 is determined based on the length of the optical fiber to be tested; SOA130 is used to intercept the target pulse signal from the scrambled pulse light signal and input the target pulse signal into the optical fiber to be tested; the target pulse signal is aligned with the rear end of the scrambled light pulse.

[0040] Furthermore, the correlation between the pulse signal period output by SOA130 and the length of the optical fiber to be measured is expressed by the following formula: ; in, T is the pulse signal period output by SOA, L is the length of the optical fiber to be tested, is the refractive index of the optical fiber, c is the speed of light in a vacuum.

[0041] In this embodiment, SOA130 (Semiconductor Optical Amplifier) ​​amplifies or suppresses the input pulsed optical signal under the control of the electrical pulse signal; for example, when the electrical pulse signal is at a high level, SOA130 amplifies the input optical signal; and when the electrical pulse signal is at a low level, SOA130 suppresses the input optical signal.

[0042] exist Figure 2 In the embodiment shown, the period of the electrical pulse signal of the SOA is set to T, which, while satisfying the correlation between the period of the optical pulse signal and the length of the optical fiber to be measured, also needs to be equal to the period of the scrambled pulse. The purpose of this is to ensure that the optical pulse period output by the SOA not only meets the system's requirements for the pulse period, but also completely retains the scrambled optical pulse; because another characteristic of the SOA is that the optical pulse it generates has an inherent chirp at the rising edge, the chirp will cause the frequency shift of the optical pulse, therefore, the pulse width of the electrical pulse designed to control the SOA in this embodiment must be wider than the pulse width required by the system, and the back ends of the scrambled optical pulse and the electrical pulse signal are aligned, thus avoiding the frequency shift problem caused by the SOA; the pulse intercepted by the SOA retains the narrow rising edge of the EOM output pulse and has the advantage of a high extinction ratio of the SOA.

[0043] The pulse light scrambling system provided by the embodiment of the present invention modulates the continuous light to be modulated into a pulse light signal through an electro-optic modulator, and realizes the scrambling of the pulse light signal by setting the ratio of the signal transmission delay time of the passive scrambler and the pulse modulation period of the electro-optic modulator to an integer, so as to obtain a scrambled pulse light signal, and finally intercepts the target pulse signal from the scrambled pulse light signal through the SOA, and outputs the target pulse signal through the optical fiber to be tested, thereby improving the efficiency of pulse light scrambling, optimizing the system volume and cost, and ensuring that the system has the high performance advantages of high pulse extinction ratio, steep rising edge, and no frequency shift.

[0044] Furthermore, the length of the second polarization-maintaining optical fiber is greater than that of the first polarization-maintaining optical fiber, and the length of the second polarization-maintaining optical fiber is greater than the coherence length of the light source; the light source is used to emit continuous light to be modulated.

[0045] In this embodiment, the delay time of the passive polarization scrambler 120 transmitting the signal through the first polarization-maintaining optical fiber and the second polarization-maintaining optical fiber and the length of each optical fiber have the following relationship: ; in, is the length of the first polarization-maintaining fiber, is the length of the second polarization-maintaining fiber, is the refractive index of the optical fiber, and c is the speed of light in a vacuum.

[0046] It should be noted that the transmission delay time of the passive polarization scrambler refers to the difference in length between the first polarization-maintaining fiber and the second polarization-maintaining fiber divided by the speed of light in the fiber, that is, the time difference in the transmission of light in the upper and lower paths; as long as the length of the second polarization-maintaining fiber is greater than the coherence length of the light source, polarization scrambling can be achieved.

[0047] It should be noted that, since the pulse light synthesized by PBC122 is required to be an arbitrary random polarization state, the phase difference between the two pulse lights needs to be a random value; and the first polarization-maintaining fiber is shorter, and the phase of the pulse light passing through this path is predictable, so it is necessary to set the phase of the pulse light passing through the second polarization-maintaining fiber to a random value; that is, only when the delay fiber is longer than the coherence length of the light source, the phase of the pulse light reaching PBC122 after transmission through the second polarization-maintaining fiber will be a random value.

[0048] At the same time, ensure the pulse cycle and delay time Satisfy the following proportional relationship: ; in, ; Note that here Need to be greater than the coherence time of the light source; by precisely controlling the delay time and the pulse period input to the passive scrambler 120 The integer multiple relationship of can effectively realize the scrambling of pulse light.

[0049] exist Figure 3 In the embodiment shown, the delay time of the signal transmitted by the first polarization-maintaining optical fiber is set to Equal to the pulse period ; At this time, the first pulse transmitted by the second polarization-maintaining optical fiber is synthesized with the second pulse of the first path in the PBC after being transmitted by the delayed optical fiber, and the second pulse of the second path is synthesized with the third pulse of the first path in the PBC, and so on, until the nth pulse of the second path is synthesized with the n+1th pulse of the first path in the PBC; because the length of the delayed optical fiber exceeds the coherence length of the light source, when the vertically polarized pulse light reaches the PBC, its phase has become an unpredictable random value, and the phase difference between the vertically polarized and parallel polarized pulse lights is also a random value, resulting in the synthesized pulse light being in a random polarization state; by Can be launched as long as the delay time Equal to the pulse period of the input passive polarization scrambler The second pulse light will arrive at PBC at the same time as a pulse of the first pulse after being transmitted through the delayed optical fiber for synthesis. The first and second subsequent pulse lights will be synthesized in PBC in turn, and the passive polarization scrambler can output a period of The scrambled pulse light; thus, by precisely controlling the delay time and the pulse period input to the passive polarization scrambler The integer multiple relationship of can effectively realize the scrambling of pulse light.

[0050] In the pulse light scrambling system provided by the embodiment of the present invention, the length of the second polarization-maintaining optical fiber is greater than the coherence length of the light source, and satisfies the integer multiple relationship between the above-mentioned delay time τ and the pulse period T1 input to the passive polarization scrambler, which can ensure that the pulse light is split by the PBS and then the scrambled light pulse signal synthesized by the PBC has the same pulse period as the pulse light signal before splitting, thereby achieving more effective and controllable pulse light scrambling.

[0051] exist Figure 4 In the embodiment shown, after receiving the laser emitted by the laser transmitter (Laser) through the polarization-maintaining optical fiber, the EOM modulates the laser into a pulsed optical signal, wherein the pulse period of the pulsed optical signal is The time difference required for light to propagate up and down the passive polarization scrambler is Determine, delay time can be set Equal to the pulse period of the input passive polarization scrambler The optical fiber between EOM and PBS is spliced ​​at 45 degrees. After passing through PBS, the pulse light is divided into two pulse lights of parallel polarization and vertical polarization, and the two optical powers are consistent (the length of the upstream optical fiber is L1, and the length of the downstream optical fiber is L2). After the pulse light of the downstream is transmitted through the delayed optical fiber, it arrives at PBC at the same time as a pulse of the upstream for synthesis. Then, the subsequent pulse lights of the upstream and downstream are synthesized in PBC in turn, and the passive polarization scrambler can output a period of The scrambled pulse light; finally, the electrical pulse signal period of the SOA is set to satisfy the following formula: ; Moreover, the electrical pulse signal period of the SOA is equal to the scrambled pulse period. Integer multiples of , to ensure that the optical pulse period output by the SOA not only meets the system's requirements for the pulse period, but also completely retains the scrambled optical pulses and avoids the frequency shift problem caused by the SOA; In summary, Figure 4 The system structure in the dotted box not only meets the system's requirements for high extinction ratio, steep rising edge, and no frequency shift of optical pulses, but also realizes polarization scrambling for such high-performance optical pulses.

[0052] The operating method of the pulse light scrambling system provided by the present invention is described below. The operating method of the pulse light scrambling system described below and the pulse light scrambling system described above can be referenced to each other.

[0053] Figure 5 FIG. 1 is a flow chart of the operation method of the optical scrambling system provided by the present invention. Figure 5 As shown, the operation method of the pulse light scrambling system includes the following steps: Step 510: modulate the continuous light to be modulated into a pulse light signal based on an electro-optic modulator (EOM).

[0054] In this step, the EOM can output an optical pulse with a rising edge of less than 1ns and an extinction ratio of about 25dB by modulating continuous light.

[0055] In this embodiment, the light emitted by the light source (such as a laser) enters the EOM through the polarization-maintaining fiber, and the EOM modulates the continuous light into a period of Pulse light signal.

[0056] Step 520, scramble the pulse light signal based on the passive polarization scrambler to obtain a scrambled pulse light signal; the ratio of the signal transmission delay time of the passive polarization scrambler to the pulse modulation period of the electro-optic modulator is an integer; the scrambled pulse light signal has the same pulse period as the pulse light signal.

[0057] In this embodiment, the period of the pulse light obtained by the passive polarization scrambling instrument can be determined by the delay time Determined; specifically, the passive polarization scrambler includes: a polarization beam splitter PBS, PBS and EOM are connected by a polarization-maintaining optical fiber; PBS is used to split the pulse light signal into vertically polarized pulse light and parallel polarized pulse light; a polarization beam combiner PBC, PBC and PBS are connected by two polarization-maintaining optical fibers, the first polarization-maintaining optical fiber is used to transmit parallel polarized pulse light, and the second polarization-maintaining optical fiber is used to transmit vertically polarized pulse light; PBC is used to synthesize the vertically polarized pulse light and the parallel polarized pulse light to obtain a scrambled pulse light signal.

[0058] In this embodiment, the optical fiber between the EOM and the PBS is fused at a certain angle, so that the pulse light is divided into polarized pulse light in a parallel direction and polarized pulse light in a perpendicular direction after passing through the PBS.

[0059] In this embodiment, the optical fiber between the EOM and the PBS is spliced ​​at 45 degrees, so that the pulse light is divided into two pulse lights of parallel polarization and vertical polarization after passing through the PBS, and the power of the two pulse lights is consistent.

[0060] Specifically, if the signal transmission delay time between the first polarization-maintaining optical fiber and the second polarization-maintaining optical fiber is Equal to the pulse period of the input passive polarization scrambler The pulse light transmitted by the second polarization-maintaining fiber will be synthesized at the same time as a pulse transmitted by the first polarization-maintaining fiber after being transmitted by the delayed fiber. Then the subsequent pulse lights of the first polarization-maintaining fiber and the second polarization-maintaining fiber will be synthesized in the PBC in turn, and the passive polarization scrambler can output scrambled pulse light with the same period as the pulse light signal.

[0061] Step 530: intercept a target pulse signal from the scrambled pulse light signal based on a semiconductor optical amplifier SOA, and input the target pulse signal into the optical fiber to be tested; align the target pulse signal with the rear end of the scrambled optical pulse; connect the SOA to a passive polarization scrambler through an optical fiber; the ratio of the period of the pulse light signal output by the SOA to the period of the scrambled pulse light signal is an integer, and the period of the pulse light signal output by the SOA is determined based on the length of the optical fiber to be tested.

[0062] In this step, the SOA amplifies or suppresses the input pulsed optical signal under the control of the electrical pulse signal; for example, when the electrical pulse signal is at a high level, the SOA amplifies the input optical signal; and when the electrical pulse signal is at a low level, the SOA suppresses the input optical signal.

[0063] In this embodiment, the pulse intercepted by the SOA retains the narrow rising edge of the EOM output pulse and has the advantage of the high extinction ratio of the SOA.

[0064] Furthermore, the relationship between the period of the optical pulse signal output by the SOA and the length of the optical fiber to be measured is expressed by the following formula: ; in, T is the pulse signal period output by SOA, L is the length of the optical fiber to be tested, is the refractive index of the optical fiber, c is the speed of light in a vacuum.

[0065] In this embodiment, the delay time of the passive polarization scrambler transmitting the signal through the first polarization-maintaining optical fiber and the second polarization-maintaining optical fiber and the length of each optical fiber have the following relationship: ; in, is the length of the first polarization-maintaining fiber, is the length of the second polarization-maintaining fiber, is the refractive index of the optical fiber, and c is the speed of light in a vacuum.

[0066] At the same time, ensure the pulse cycle and delay time Satisfy the following proportional relationship: ; in, ; Note that here Need to be greater than the coherence time of the light source; by precisely controlling the delay time and the pulse period input to the passive polarization scrambler The integer multiple relationship of can effectively realize the scrambling of pulse light.

[0067] The operating method of the pulse light scrambling system provided by the embodiment of the present invention modulates the continuous light to be modulated into a pulse light signal through an electro-optical modulator, and realizes the scrambling of the pulse light signal by setting the ratio of the signal transmission delay time of the passive scrambler and the pulse modulation period of the electro-optical modulator to an integer, so as to obtain a scrambled pulse light signal, and finally intercepts a target pulse signal aligned with the rear end of the scrambled light pulse from the scrambled pulse light signal through an SOA, and outputs the target pulse signal through the optical fiber to be tested, thereby improving the efficiency of pulse light scrambling, optimizing the system volume and cost, and ensuring that the system has the high performance advantages of high pulse extinction ratio, steep rising edge, and no frequency shift.

[0068] Figure 6 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 6As shown, the electronic device may include: a processor 610, a communication interface 620, a memory 630 and a communication bus 640, wherein the processor 610, the communication interface 620 and the memory 630 communicate with each other through the communication bus 640. The processor 610 may call the logic instructions in the memory 630 to execute the operation method of the pulse light scrambling system, the method comprising: modulating the continuous light to be modulated into a pulse light signal based on the electro-optic modulator EOM; scrambling the pulse light signal based on the passive scrambler to obtain a scrambled pulse light signal; the ratio of the signal transmission delay time of the passive scrambler to the pulse modulation period of the electro-optic modulator is an integer; the scrambled pulse light signal has the same pulse period as the pulse light signal; intercepting the target pulse signal from the scrambled pulse light signal based on the semiconductor optical amplifier SOA, and inputting the target pulse signal into the optical fiber to be tested; aligning the target pulse signal with the rear end of the scrambled optical pulse; and connecting the SOA and the passive scrambler through an optical fiber.

[0069] In addition, the logic instructions in the above-mentioned memory 630 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0070] On the other hand, the present invention also provides a computer program product, which includes a computer program, and the computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the operation method of the pulse light scrambling system provided by the above methods, and the method includes: modulating the continuous light to be modulated into a pulse light signal based on an electro-optical modulator EOM; scrambling the pulse light signal based on a passive scrambler to obtain a scrambled pulse light signal; the ratio of the signal transmission delay time of the passive scrambler to the pulse modulation period of the electro-optical modulator is an integer; the scrambled pulse light signal and the pulse period of the pulse light signal are the same; based on a semiconductor optical amplifier SOA, intercepting a target pulse signal from the scrambled pulse light signal, and inputting the target pulse signal into the optical fiber to be tested; aligning the rear ends of the target pulse signal and the scrambled light pulse; and connecting the SOA and the passive scrambler through an optical fiber.

[0071] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the operation method of the pulse light scrambling system provided by the above-mentioned methods, the method comprising: modulating the continuous light to be modulated into a pulse light signal based on an electro-optical modulator EOM; scrambling the pulse light signal based on a passive scrambler to obtain a scrambled pulse light signal; the ratio of the signal transmission delay time of the passive scrambler to the pulse modulation period of the electro-optical modulator is an integer; the scrambled pulse light signal and the pulse light signal have the same pulse period; intercepting a target pulse signal from the scrambled pulse light signal based on a semiconductor optical amplifier SOA, and inputting the target pulse signal into the optical fiber to be tested; aligning the rear ends of the target pulse signal and the scrambled light pulse; and connecting the SOA and the passive scrambler through an optical fiber.

[0072] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0073] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pulse light scrambling system, characterized in that: include: An electro-optic modulator EOM, which is used to modulate the continuous light to be modulated into a pulse light signal; A passive polarization scrambler, wherein the ratio of the signal transmission delay time of the passive polarization scrambler to the pulse modulation period of the electro-optical modulator is an integer; the passive polarization scrambler is used to scramble the pulse light signal to obtain a scrambled pulse light signal; the scrambled pulse light signal has the same pulse period as the pulse light signal; A semiconductor optical amplifier SOA, wherein the SOA is connected to the passive polarization scrambler via an optical fiber; the ratio of the period of the pulse signal output by the SOA to the period of the pulse light signal is an integer, and the period of the pulse signal output by the SOA is determined based on the length of the optical fiber to be tested; the SOA is used to intercept a target pulse signal from the scrambled pulse light signal and input the target pulse signal into the optical fiber to be tested; the target pulse signal is aligned with the rear end of the scrambled optical pulse.

2. The pulse light polarization scrambling system according to claim 1, characterized in that: The passive polarization scrambler comprises: A polarization beam splitter PBS, wherein the PBS is connected to the EOM via an optical fiber; the PBS is used to split the pulse light signal into vertically polarized pulse light and parallel polarized pulse light; A polarization beam combiner PBC, wherein the PBC is connected to the PBS via two polarization-maintaining optical fibers, wherein the first polarization-maintaining optical fiber is used to transmit the parallel polarized pulsed light, and the second polarization-maintaining optical fiber is used to transmit the vertically polarized pulsed light; the PBC is used to synthesize the vertically polarized pulsed light and the parallel polarized pulsed light to obtain the scrambled pulsed light signal.

3. The pulse light scrambling system according to claim 2, characterized in that: The optical fiber between the PBS and the EOM is fused at 45 degrees.

4. The pulse light scrambling system according to claim 2, characterized in that: The length of the second polarization-maintaining optical fiber is greater than the length of the first polarization-maintaining optical fiber, and the length of the second polarization-maintaining optical fiber is greater than the coherence length of a light source; the light source is used to emit the continuous light to be modulated; The delay time of the passive polarization scrambler transmitting the signal through the first polarization-maintaining optical fiber and the second polarization-maintaining optical fiber and the length of each optical fiber have the following relationship: ； in, is the length of the first polarization-maintaining optical fiber, is the length of the second polarization-maintaining fiber, is the refractive index of the optical fiber, and c is the speed of light in a vacuum.

5. The pulse light polarization scrambling system according to claim 1, characterized in that: The pulse signal period of the SOA output is determined based on the following formula: ； in, T is the pulse signal period output by the SOA, L is the length of the optical fiber to be tested, is the refractive index of the optical fiber, c is the speed of light in a vacuum.

6. A method for operating a pulse light scrambling system, characterized in that: include: The continuous light to be modulated is modulated into a pulsed light signal based on an electro-optical modulator (EOM); The pulse light signal is scrambled based on a passive polarization scrambler to obtain a scrambled pulse light signal; the ratio of the signal transmission delay time of the passive polarization scrambler to the pulse modulation period of the electro-optical modulator is an integer; the scrambled pulse light signal and the pulse light signal have the same pulse period; A target pulse signal is intercepted from the scrambled pulse light signal based on a semiconductor optical amplifier SOA, and the target pulse signal is input into the optical fiber to be tested; the target pulse signal is aligned with the rear end of the scrambled optical pulse; the SOA is connected to the passive scrambler through an optical fiber; The ratio of the period of the pulse light signal output by the SOA to the period of the scrambled pulse light signal is an integer, and the period of the pulse light signal output by the SOA is determined based on the length of the optical fiber to be tested.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the operating method of the pulse light scrambling system according to any one of claims 1 to 6 is implemented.

8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the operating method of the pulse light scrambling system according to any one of claims 1 to 6 is implemented.

9. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the operating method of the pulse light scrambling system according to any one of claims 1 to 6 is implemented.

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