Laser interference source device for multi-channel pseudo-random code modulation

Abstract

The invention discloses a multi-channel pseudo-random code modulation laser interference source device. The device comprises a pseudo-random code modulator, an external modulation laser group, an optical fiber beam splitter group, an optical fiber buncher and a two-dimensional galvanometer which are arranged in sequence, according to the invention, laser modulation is carried out through the pseudo-random code pulse modulator, pseudo-random pulse codes are generated, and optical interference pulses with different coded signals are generated; two-dimensional galvanometer light beam deflection control is adopted, and control over laser interference signals in different directions can be achieved; a multi-path 1 * 2 optical fiber beam splitter and a multi-path 1 * 8 optical fiber beam splitter are adopted, beam splitting of coding signals of the same type is achieved, and the function of transmitting multi-channel interference light beams at the same time is established. According to the invention, emission of light interference signals of different codes is realized, a function of simulating laser radar light signals of unmanned vehicles produced by different manufacturers is realized, a function of simultaneously emitting multiple paths of light interference signals is realized, and a problem of simulating complex light interference environment signals in practical application of the unmanned vehicles is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of lidar, and in particular to a laser jamming source device with multi-channel pseudo-random code modulation. Background Art

[0002] At present, single-photon detection has technical advantages such as high spatio-temporal resolution, long detection distance, and wide spectral response. However, single-photon detection is easily interfered by background and stray light. Especially in the daytime environment, the strong background scattering of sunlight causes serious false alarms in single-photon detection, and even blocks the channels, making it impossible to perform optoelectronic detection or imaging. To solve the anti-interference problem, coding modulation is usually adopted during single-photon detection to reduce interference.

[0003] To verify the anti-interference ability of a single-photon detection system during detection and imaging, a simulation source or interference system is usually established to conduct interference tests during single-photon detection to verify the anti-interference ability of single-photon detection. However, traditional jamming sources are usually in a fixed mode or a single-channel mode, and cannot effectively simulate the multi-interference light forms in complex scenarios during actual application. Especially, they cannot simulate the test scenarios of multi-beam, multi-coding, and multi-direction simultaneous interference in the large-scale application scenario of unmanned vehicles, making the verification and evaluation of the anti-interference effect of the single-photon detection system incomplete. Summary of the Invention

[0004] The purpose of the present invention is to provide a laser jamming source device with multi-channel pseudo-random code modulation, which can solve the problem of simultaneous interference of multi-mode photons in a single-photon detection in a complex scenario.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A laser jamming source device with multi-channel pseudo-random code modulation, comprising: a pseudo-random code modulator, an external modulation laser group, an optical fiber beam splitter group, an optical fiber beam combiner, and a two-dimensional galvanometer, which are arranged in sequence;

[0007] The pseudo-random code modulator is used to generate a prepared modulation signal, modulate the external modulation laser group to form a pulsed optical signal, and establish a pseudo-random coding sequence for the output of the target interference light source;

[0008] The external modulation laser group is used to generate a pulsed optical signal under the control of the pseudo-random code modulator and the amplification of the internal optical signal thereof, and form a coded optical signal pulse with a pseudo-random sequence through the coding relationship between the lasers in the external modulation laser group;

[0009] The optical fiber beam splitter group is used to distribute the optical power of the pulsed laser generated by the external modulation laser group to form a plurality of optical pulse signals with equivalent power for output;

[0010] The optical fiber beam combiner is used to combine and arrange the multiple optical signals distributed by the optical fiber beam splitter group to form a laser array arranged in a 3×16 rectangular array;

[0011] The two-dimensional galvanometer is used to deflect and position the light beam emitted by the optical fiber beam combiner in different spatial directions to achieve the function of controlling optical interference in different directions.

[0012] The pseudo-random code modulator further includes: a clock chip, an integrated circuit, and three TTL interface circuits;

[0013] The clock chip generates a clock signal of 125 MHz to supply the integrated circuit to generate a timing relationship; the integrated circuit uses the XC7Z100 model and is used to generate an 8-bit pseudo-random code; the three TTL interface circuits are respectively connected to the integrated circuit to generate pulse modulation signals, and the generated pulse modulation signals have an 8-bit pseudo-random code pattern between them.

[0014] The principle of pseudo-random code modulation generated by the pseudo-random code modulator is as follows:

[0015] The intervals between the three pulses generated by the pseudo-random code modulator are ΔT1 and ΔT2 respectively. When starting to work, the pseudo-random code modulator randomly generates ΔT1 and ΔT2, that is, for each pulse sequence, the interval characteristics between the three pulses in its pulse group are different; the time interval between pulse groups is ΔTi, and during the working process, the value of ΔTi is randomly generated according to the pseudo-random sequence status code; the three time intervals of ΔTi, ΔT1, and ΔT2 constitute an 8-bit pseudo-random code; the mathematical function of 8-bit pseudo-random code modulation is as follows:

[0016]

[0017] Among them, ΔTb is a fixed pulse interval; ΔTv is the minimum pulse interval adjustment amount, which is related to the hardware performance, such as 50 ps to 100 ns; ki, k2, and k3 are coefficients generated by the pseudo-random sequence status code.

[0018] The optical fiber beam splitter group further includes: a 1×2 optical fiber beam splitter with a ratio of 50:50 in the 1550 nm band and a 1×8 optical fiber beam splitter with a ratio of 12.5:12.5:12.5:12.5:12.5:12.5:12.5:12.5 in the 1550 nm band; the 1×2 optical fiber beam splitter with a ratio of 50:50 in the 1550 nm band is used to split the pulse modulation light beam generated by the external modulation laser group to form two light beams with equivalent power; the 1×8 optical fiber beam splitter in the 1550 nm band splits the light beam split by the 1×2 optical fiber beam splitter again to form more light beams with equivalent power for simultaneous signal interference.

[0019] The described two-dimensional galvanometer is composed of an azimuth mirror and a pitch mirror with an effective aperture of ￠20mm, jointly forming the deflection and positioning of the light beam in the two-dimensional space. Through the combination of the two, a light beam interference space with an azimuth deflection angle range of ±20° and a pitch angle deflection range of ±20° is formed.

[0020] In the present invention, a laser is modulated by a pseudo-random code pulse modulator to generate pseudo-random pulse codes, realizing the generation of optical interference pulses with different coding signals; two-dimensional galvanometer beam deflection control is adopted to realize the control of laser interference signals in different directions; a multi-channel 1×2 optical fiber splitter and a multi-channel 1×8 optical fiber splitter are used to realize the splitting of the same type of coding signals and establish the simultaneous emission function of multi-channel interference light beams. The present invention has the function of simultaneously emitting 48 optical interference pulse coding signals, has the ability of 8-bit pseudo-random code modulation, and has a beam deflection control direction in the range of ±20°. It not only realizes the emission of optical interference signals with different codings and solves the function of simulating the optical signals of lidars on driverless vehicles produced by different manufacturers, but also has the function of simultaneously emitting multi-channel optical interference signals, solves the problem of simulating complex optical interference environment signals in the actual application of driverless vehicles, and provides a simulation environment for verifying the anti-interference performance of single-photon imaging radars in actual applications. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 It is a structural principle block diagram of the present invention.

[0023] Figure 2 It is a block diagram of the composition of the pseudo-random code modulator of the present invention.

[0024] Figure 3 It is a composition diagram of the pseudo-random code pulse coding of the present invention. Detailed Embodiments

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0026] Such as Figure 1As shown in the figure, the present invention is composed of a pseudo-random code modulator 100, an external modulation laser group 200, an optical fiber beam splitter group 300, an optical fiber beam combiner 400, and a two-dimensional galvanometer 500.

[0027] The pseudo-random code modulator 100 is used to generate a prepared modulation signal, modulate the external modulation laser group to form a pulsed optical signal, and establish a pseudo-random coding sequence for the output of the target interference light source.

[0028] The external modulation laser group 200 is used to generate a pulsed optical signal under the control of the pseudo-random code modulator and the amplification of the internal optical signal, and form a coded optical signal pulse with a pseudo-random sequence through the coding relationship between the lasers in the external modulation laser group.

[0029] The optical fiber beam splitter group 300 is used to distribute the optical power of the pulsed laser generated by the external modulation laser group to form multiple output optical pulse signals with equivalent power.

[0030] The optical fiber beam combiner 400 is used to combine and arrange the multiple optical signals distributed by the optical fiber beam splitter group to form a laser array arranged in a 3×16 rectangular array.

[0031] The two-dimensional galvanometer 500 is used to deflect and position the light beam emitted by the optical fiber beam combiner in different spatial directions to achieve the optical interference control function in different directions.

[0032] The external modulation laser group 200 is composed of a first and second fiber laser 10, a second fiber laser 220, and a third fiber laser 230. The optical fiber beam splitter group 300 is composed of a first optical fiber beam splitter 310, a second optical fiber beam splitter 320, a third optical fiber beam splitter 330, a first optical fiber beam splitter 340, a second optical fiber beam splitter 350, a third optical fiber beam splitter 360, a fourth optical fiber beam splitter 370, a fifth optical fiber beam splitter 380, and a sixth optical fiber beam splitter 390.

[0033] Its working process is as follows: After the multi-channel pseudo-random code modulated laser jamming source device is powered on, the pseudo-random code modulator 100 will generate three modulated signals, which are respectively input into the first and second fiber lasers 10, the second fiber laser 220, and the third fiber laser 230, so that the first and second fiber lasers 10, the second fiber laser 220, and the third fiber laser 230 all generate pulsed optical signal outputs under the modulation of the external modulation signal. At the same time, among the three signals of the first and second fiber lasers 10, the second fiber laser 220, and the third fiber laser 230, they follow the modulated pseudo-random coding mode. The pulsed signal output by the first and second fiber lasers 10 is input into the first fiber beam splitter 310. After the beam splitting of the first fiber beam splitter 310, two pulsed modulation signals with equivalent power are formed, and the two optical modulation signals are respectively input into the first fiber beam splitter 340 and the second fiber beam splitter 350; after the beam splitting of the first fiber beam splitter 340 and the second fiber beam splitter 350, 16 optical modulation signals are formed and input into the fiber beam combiner 300; the pulsed signal output by the second fiber laser 220 is input into the second fiber beam splitter 320. After the beam splitting of the second fiber beam splitter 320, two pulsed modulation signals with equivalent power are formed, and the two optical modulation signals are respectively input into the third fiber beam splitter 360 and the fourth fiber beam splitter 370; after the beam splitting of the third fiber beam splitter 360 and the fourth fiber beam splitter 370, 16 optical modulation signals are formed and input into the fiber beam combiner 300; the pulsed signal output by the third fiber laser 230 is input into the third fiber beam splitter 330. After the beam splitting of the third fiber beam splitter 330, two pulsed modulation signals with equivalent power are formed, and the two optical modulation signals are respectively input into the fifth fiber beam splitter 380 and the sixth fiber beam splitter 390; after the beam splitting of the fifth fiber beam splitter 380 and the sixth fiber beam splitter 390, 16 optical modulation signals are formed and input into the fiber beam combiner 300; the fiber beam combiner 300 receives the input optical signals from the first fiber beam splitter to the sixth fiber beam splitter, forms a fiber optic beam array with 48 channels, and emits it towards the target jamming space after passing through the two-dimensional galvanometer 500.

[0034] The pseudo-random code modulator 100 proposed by this invention consists of a 125 MHz clock chip, an integrated circuit of XC7Z100, and 3-way SN74LVC2T45 TTL interface circuits. Under the clock information input by the clock chip to the integrated circuit, 3-way pulsed signals are generated, and an 8-bit pseudo-random code is formed among the 3-way pulsed signals; the 3-way pulsed signals respectively pass through the TTL interface circuits to form laser modulation signals, and after the laser modulation signals are respectively loaded onto the external modulation laser set 200, pulsed optical signals with an 8-bit pseudo-random code are formed.

[0035] The intervals between the three pulses generated by the pseudo-random code modulator 100 proposed by the present invention are ΔT1 and ΔT2 respectively. When starting to work, the pseudo-random code modulator randomly generates ΔT1 and ΔT2, that is, for each pulse sequence, the interval characteristics between the three pulses in its pulse group are all different; the time interval between pulse groups is ΔTi, and during the working process, the value of ΔTi is randomly generated according to the pseudo-random sequence status code. The three time intervals ΔTi, ΔT1, and ΔT2 constitute an 8-bit pseudo-random code. The mathematical function of the 8-bit pseudo-random code modulation is as follows:

[0036]

[0037] Among them, ΔTb is a fixed pulse interval. For example, when the laser repetition frequency is 10 MHz, its value is 100 ns; ΔTv is the minimum pulse interval adjustment amount, which is related to the hardware performance, such as 50 ps to 100 ns; ki, k2, and k3 are pseudo-random adjustment coefficients, which are generated by different pseudo-random code sequence status codes.

[0038] The fiber optic beam splitter group 300 proposed by the present invention uses three groups of 1×2 fiber optic beam splitters with a 50:50 ratio in the 1550 nm band and six groups of 1×8 fiber optic beam splitters with a 12.5:12.5:12.5:12.5:12.5:12.5:12.5:12.5 ratio in the 1550 nm band to simultaneously output 48 optical pulses with equivalent power for each path.

[0039] The two-dimensional galvanometer 500 proposed by the present invention is composed of an azimuth mirror and an elevation mirror with an effective aperture of ￠20 mm, which jointly form the deflection and positioning of the light beam in the two-dimensional space. Through the combination of the two, a light beam interference space with an azimuth deflection angle range of ±20° and an elevation angle deflection range of ±20° is formed.

[0040] In summary, a multi-channel pseudo-random code modulated laser jamming source device of the present invention uses a pseudo-random code pulse modulator to modulate a laser, generates pseudo-random pulse codes, and realizes the generation of optical interference pulses with different coding signals; uses two-dimensional galvanometer beam deflection control to realize the control of laser interference signals in different directions; uses multiple 1×2 fiber optic beam splitters and multiple 1×8 fiber optic beam splitters to realize the beam splitting of the same type of coding signals and establish the function of simultaneous emission of multi-channel interference light beams. The device not only realizes the generation of 8-bit coded optical interference signals and solves the function of simulating the optical signals of lidars of unmanned vehicles produced by different manufacturers, but also has the function of simultaneous emission of multi-channel optical interference signals, solves the problem of simulating complex optical interference environment signals in the actual application of unmanned vehicles, and provides a simulation environment for verifying the anti-jamming performance of single-photon imaging radars in actual applications.

[0041] Compared with traditional optical interference sources, a laser interference source device with multi-channel pseudo-random code modulation according to the present invention uses a pseudo-random code pulse modulator to modulate a laser, generating pseudo-random pulse codes to realize the generation of optical interference pulses with different coding signals; adopts two-dimensional galvanometer beam deflection control to realize the control of laser interference signals in different directions; and adopts multi-channel 1×2 optical fiber splitters and multi-channel 1×8 optical fiber splitters to realize the splitting of the same type of coding signals and establish the simultaneous emission function of multi-channel interference beams.

[0042] The present invention proposes a laser interference source device with multi-channel pseudo-random code modulation. This device can effectively simulate the multi-interference light forms in complex scenarios during actual applications, especially simulate the application scenario of simultaneous interference of multiple beams, multiple codes, and multiple directions in the large-scale application scenario of driverless vehicles, making the verification and evaluation of the anti-interference effect of single-photon detection imaging systems more complete.

[0043] The present invention not only has the interference performance of traditional single fixed modes, but also, due to the addition of a pseudo-random modulation method, can realize the simultaneous interference of 48-channel beams and multi-mode coding, and can verify the simultaneous anti-interference performance of single-photon detection systems in multi-beam and multi-coding modes. Compared with traditional optical interference sources, a laser interference source device with multi-channel pseudo-random code modulation according to the present invention uses...

[0044] In the description of the present invention, it should be noted that for orientation terms, if there are terms such as "center", "horizontal", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation and position relationship is based on the orientation or position relationship shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as limiting the specific protection scope of the present invention.

[0045] It should be noted that the terms "comprising" and "having" and any variations thereof in the description and claims of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0046] Note that the above is only a preferred embodiment of the present invention and the application of technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the specific embodiments described herein. Without departing from the concept of the present invention, more other effective embodiments can also be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A laser jamming source device with multi-channel pseudo-random code modulation, characterized in that: It includes: A pseudo-random code modulator, an external modulation laser group, an optical fiber beam splitter group, an optical fiber beam combiner, and a two-dimensional galvanometer arranged in sequence; The pseudo-random code modulator is used to generate a programmed modulation signal, modulate the external modulation laser group to form a pulsed optical signal, and establish a pseudo-random coding sequence for output of the target jamming light source; The external modulation laser group is used to generate a pulsed optical signal under the control of the pseudo-random code modulator and the amplification of the internal optical signal thereof, and form a coded optical signal pulse with a pseudo-random sequence through the coding relationship between the lasers in the external modulation laser group; The optical fiber beam splitter group is used to distribute the optical power of the pulsed laser generated by the external modulation laser group to form multiple output optical pulse signals with equivalent power; The optical fiber beam combiner is used to bundle and arrange the multiple optical signals distributed by the optical fiber beam splitter group to form a laser array arranged in a 3×16 rectangular array; The two-dimensional galvanometer is used to deflect and position the light beam emitted by the optical fiber beam combiner in different spatial directions to achieve the light jamming control function in different directions.

2. The laser jamming source device with multi-channel pseudo-random code modulation according to claim 1, characterized in that, The pseudo-random code modulator further includes: a clock chip, an integrated circuit, and 3 TTL interface circuits; The clock chip generates a 125 MHz clock signal to supply the integrated circuit to generate a timing relationship; the integrated circuit uses the XC7Z100 model and is used to generate an 8-bit pseudo-random code; the 3 TTL interface circuits are respectively connected to the integrated circuit to generate a pulsed modulation signal, and the generated pulsed modulation signals have an 8-bit pseudo-random code pattern therebetween.

3. The laser interference source device with multi-channel pseudo-random code modulation according to claim 1, characterized in that, The pseudo-random code modulation principle generated by the pseudo-random code modulator is as follows: The intervals between the 3 pulses generated by the pseudo-random code modulator are ΔT1 and ΔT2 respectively. When starting to work, the pseudo-random code modulator randomly generates ΔT1 and ΔT2, that is, for each pulse sequence, the interval characteristics between the three pulses in its pulse group are all different; the time interval between pulse groups is ΔTi, and during the working process, the value of ΔTi is randomly generated according to the pseudo-random sequence status code; the three time intervals of ΔTi, ΔT1, and ΔT2 constitute an 8-bit pseudo-random code; the mathematical function of the 8-bit pseudo-random code modulation is as follows: Where, ΔTb is a fixed pulse interval; ΔTv is the minimum pulse interval adjustment amount, which is related to the hardware performance, such as 50 ps to 100 ns; ki, k2, and k3 are coefficients generated by the pseudo-random sequence status code.

4. A laser jamming source device with multi-channel pseudo-random code modulation according to claim 1, characterized in that, The optical fiber beam splitter group further includes: a 1×2 optical fiber beam splitter with a 50:50 ratio in the 1550 nm band and a 1×8 optical fiber beam splitter with a 12.5:12.5:12.5:12.5:12.5:12.5:12.5:12.5 ratio in the 1550 nm band; The 1550nm-band 50:50 1×2 fiber optic splitter is used to split the pulsed modulated light beam generated by the external modulation laser group to form two light beams with comparable powers; the 1550nm-band 1×8 fiber optic splitter splits the light beam after being split by the 1×2 fiber optic splitter again to form more light beams with comparable powers for simultaneously interfering with signals.

5. The laser jamming source device with multi-channel pseudo-random code modulation according to claim 1, characterized in that The two-dimensional galvanometer is composed of an azimuth mirror and a pitch mirror with an effective aperture of ￠20mm, jointly forming the deflection and positioning of the two-dimensional space light beam. Through the combination of the two, a light beam interference space with an azimuth deflection angle range of ±20° and a pitch angle deflection range of ±20° is formed.

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