Distributed radar and laser radar system based on chaotic optical comb

Abstract

The invention discloses a distributed radar and laser radar system based on a chaotic optical comb, and belongs to the technical field of microwave photonics and laser. The distributed radar and laser radar system comprises a chaotic optical comb signal generation module, a wavelength division multiplexer, N optical fibers and N radar and laser radar modules. A chaotic optical comb signal generated by the chaotic optical comb signal generation module is divided into N single chaotic optical signals with different wavelengths in the wavelength division multiplexer; the N single chaotic optical signals with different wavelengths are respectively transmitted to the N radar and laser radar modules at different spatial positions through the N optical fibers, so that spatial distribution of the signals is realized. The single chaotic optical comb signal source is combined with the wavelength division multiplexer and the optical fiber, sensing signals are provided for a plurality of radar and laser radar modules which are arranged in a distributed mode, generation and distribution of multi-path distributed sensing signals are achieved, a traditional multi-source scheme is replaced, system cost, size and complexity are reduced, and compact 360-degree annular sensing array deployment is supported.

Description

Technical Field

[0001] This invention belongs to the fields of microwave photonics and laser technology, specifically relating to a distributed radar and lidar system based on a chaotic optical comb. Background Technology

[0002] Achieving zero accidents is one of the core goals of advanced autonomous systems driven by artificial intelligence. By integrating microwave and optical sensing technologies, autonomous vehicles, drones, and robots can maintain accurate environmental perception under various weather conditions and achieve efficient interaction with the outside world, thereby significantly reducing the risk of accidents. Microwave sensing systems, represented by radar, have continuous ranging capabilities, and their microwave signals can penetrate interference media such as dust, fog, rain, and snow; while optical sensing systems, represented by lidar, can achieve high-resolution distance measurement thanks to the shorter wavelength of light.

[0003] Beyond the all-weather perception advantages offered by microwave and optical sensor fusion technology, integrating more sensors into automated systems is crucial for achieving the goal of zero accidents in commercially available autonomous vehicles. However, the rapid increase in the number of microwave and optical sensor units in a single system, along with the continuous rise in the number of unmanned systems in the same airspace, has led to increasingly complex electromagnetic and optical environments, posing both technical and cost challenges to microwave and optical sensor fusion systems. For example, commercially available or soon-to-be-commercialized Time-of-Flight (ToF) and Frequency Modulated Continuous Wave (FMCW) radar or lidar systems often face signal interference problems due to overlapping microwave or optical channels. In complex electromagnetic and optical environments, time confusion caused by the superposition of echo signals with other channels or source signals in Time-of-Flight systems, and frequency confusion caused by the overlap of operating frequencies with other signal sources in FMCW systems, both lead to decreased ranging accuracy and increased accident risk. Therefore, to address the time and frequency congestion problems of radar and lidar, sensor signal sources need to have strong anti-interference capabilities to effectively reduce accident risk. Furthermore, the surge in the number of microwave and optical sensor units in traditional solutions means the need for a large number of independent signal sources, significantly increasing system complexity and cost.

[0004] Therefore, developing a sensing system that has all-weather and high-resolution sensing capabilities, simple structure, controllable cost, strong anti-interference ability, and can effectively reduce accident risks or even achieve the goal of zero accidents has become a key issue that urgently needs to be solved. Summary of the Invention

[0005] The purpose of this invention is to address the problems existing in the background technology by proposing a distributed radar and lidar system based on chaotic optical combs. This system uses a single chaotic optical comb signal source as its core, and through wavelength division multiplexing and fiber optic transmission, provides sensing signals to multiple distributed radar and lidar modules. This achieves a 360-degree circular sensing array while significantly reducing system size and cost. Specifically, the same chaotic optical signal is used simultaneously for both radar and lidar modules within the system, enabling signal source sharing. Furthermore, leveraging the inherent orthogonality of chaotic signals, the system possesses strong anti-interference capabilities, effectively suppressing time and frequency confusion in multi-channel environments, thereby improving ranging accuracy and reducing the risk of accidents.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A distributed radar and lidar system based on chaotic optical combs includes a chaotic optical comb signal generation module, a wavelength division multiplexer, and N One optical fiber, and N One radar and lidar module; The chaotic optical comb signal generation module generates a chaotic optical comb signal; the wavelength division multiplexer divides the generated chaotic optical comb signal into... N A single chaotic light signal of different wavelengths; N A single chaotic light signal of different wavelengths passes through N Each optical fiber transmits to a different location in space. N Individual radar and lidar modules enable spatially distributed signal distribution, and these modules also provide microwave and optical sensing capabilities. N It is a positive integer ≥ 2; The radar and lidar module includes an optical coupler, a radar transceiver module, and a lidar transceiver module. The optical coupler splits the input single chaotic optical signals of different wavelengths into two paths, which are then sent to the radar transceiver module and the lidar transceiver module respectively, so as to realize the sharing of the same optical signal on the radar and lidar modules. In the radar transceiver module, single chaotic optical signals of different wavelengths (as shown in the figure) n Taking a chaotic optical signal of a certain wavelength as an example, its n It is an integer, and 1 ≤ n ≤ NThe signal is converted into a chaotic electrical signal by photodetector 1 and split into three branches by an electrical coupler. The output signal of branch 1 is used as a radar detection signal, the output signal of branch 2 is used as a radar reference signal, and the output signal of branch 3 is used as a lidar reference signal. The radar detection signal output from branch 1 is used by the radar transmitting module to detect the target and the radar echo signal is received by the radar receiving module. The radar reference signal output from branch 2 and the received radar echo signal are processed by the radar signal cross-correlation analysis unit. The target distance is determined based on the pulse delay position in the cross-correlation result, realizing the microwave sensing function and thus having all-weather sensing capability. In the lidar transceiver module, another chaotic optical signal from the same input optical signal is directly used as the lidar detection signal to detect the target via the lidar transmitting module, and the lidar echo signal is received by the lidar receiving module. The received lidar echo signal is converted into a lidar electrical echo signal by the photodetector 2. The lidar reference signal from the electrical coupler branch 3 in the lidar transceiver module and the lidar electrical echo signal converted by the photodetector 2 are then processed by the lidar signal cross-correlation analysis unit. The target distance is determined based on the pulse delay position in the cross-correlation result, thereby realizing the optical sensing function and achieving high-resolution perception capability.

[0007] Furthermore, assuming that the pulse delay positions output by the radar signal cross-correlation analysis unit and the lidar signal cross-correlation analysis unit are respectively τ 1 and τ 2. The distance of the target detected by radar and lidar L 1 and L 2. Satisfies: L 1= cτ 1 / 2, L 2= c τ 2 / 2, c y is the speed of light in a vacuum.

[0008] Furthermore, the chaotic optical comb signal generation module can be implemented using a microcavity optical comb or laser self-injection locking, but is not limited to these two solutions.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention provides a distributed radar and lidar system based on chaotic optical comb, which uses a single chaotic optical comb signal source combined with wavelength division multiplexer and optical fiber to provide sensing signals for multiple distributed radar and lidar modules, realizes the generation and distribution of multiple distributed sensing signals, replaces the traditional multi-source scheme, reduces system cost, size and complexity, and supports compact 360-degree ring sensing array deployment.

[0010] 2. The present invention provides a distributed radar and lidar system based on chaotic optical comb, which simultaneously drives the radar and lidar sensing functions through the same signal source, realizing the coordinated operation of all-weather microwave sensing and high-resolution optical sensing.

[0011] 3. The present invention provides a distributed radar and lidar system based on chaotic optical combs. By utilizing the inherent orthogonality of chaotic signals, the system has strong anti-interference capabilities, effectively avoiding time and frequency confusion and reducing the risk of accidents.

[0012] 4. The present invention provides a distributed radar and lidar system based on chaotic optical comb, which provides a reference signal for lidar transceiver module through the shared branch (branch 3) of the electrical coupler, thereby improving hardware utilization and enhancing system integration and coordination. Attached Figure Description

[0013] Figure 1 A schematic diagram of a distributed radar and lidar system based on a chaotic optical comb provided by the present invention; Figure 2 A schematic diagram of the structure of the radar and lidar modules in a distributed radar and lidar system based on a chaotic optical comb provided by the present invention; Figure 3 This is a schematic diagram of a distributed radar and lidar system based on a chaotic optical comb, according to Embodiment 1 of the present invention. Figure 4 This is a schematic diagram of a distributed radar and lidar system based on a chaotic optical comb, according to Embodiment 2 of the present invention. Figure 5 This is a schematic diagram illustrating the determination of target distance based on the output results of the radar signal cross-correlation analysis unit and the lidar signal cross-correlation analysis unit in a distributed radar and lidar system based on a chaotic optical comb, as described in Embodiments 1 and 2 of the present invention. Detailed Implementation

[0014] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0015] like Figure 3 As shown, this embodiment provides a distributed radar and lidar system based on a chaotic optical comb, including a laser 1, a micro-resonant cavity 2, a wavelength division multiplexer 3, and an optical fiber. n4. Optical coupler; 5. Photodetector; 6. Electrical coupler; 7. Transmitting antenna; 8. Receiving antenna; 9. Radar signal cross-correlation analysis unit; 10. Optical circulator; 11. Collimator; 12. Photodetector; 13. and lidar signal cross-correlation analysis unit; 14. The optical signal output from laser 1 is injected into microresonant cavity 2, generating a chaotic optical comb signal. This chaotic optical comb signal is then generated by wavelength division multiplexer 3. N A single chaotic optical signal of different wavelengths. (The sentence is incomplete and requires further context.) n wavelengths ( n It is an integer, and 1 ≤ n ≤ N Taking a chaotic optical signal as an example, the signal passes through the corresponding optical fiber. n Transmitted to the n The first radar and lidar module. In this module, optical coupler 5 will receive the input from the first... n The chaotic optical signal of wavelength is split into two paths, which are used for the ... n The radar transceiver module and the first n One LiDAR transceiver module.

[0016] In the radar transceiver module, the chaotic optical signal is converted into an electrically chaotic signal by a photodetector 6, and then split into three branches by an electrocoupler 7: the output signal of branch 1 is used as the radar detection signal, the output signal of branch 2 is used as the radar reference signal, and the output signal of branch 3 is used as the lidar reference signal. The radar detection signal output from branch 1 is used to detect the radar target via the transmitting antenna 8, and its echo is received by the receiving antenna 9. The radar echo signal and the radar reference signal output from branch 2 are input to the radar signal cross-correlation analysis unit 10. By calculating the cross-correlation result and determining the target distance based on the pulse delay position, the microwave sensing function is realized.

[0017] In the lidar transceiver module, the chaotic light signal first passes through the optical circulator 11, and then through the collimator 12 to detect the lidar target. The echo signal reflected from the target passes through the collimator 12 and the optical circulator 11 in sequence, and is then converted into a lidar electrical echo signal by the photodetector 13. The lidar reference signal output from branch 3, together with the lidar electrical echo signal, enters the lidar signal cross-correlation analysis unit 14. By calculating the cross-correlation result, the pulse delay position is obtained, and the target distance is determined accordingly, thus realizing the optical sensing function.

[0018] The schematic diagram illustrating the determination of target distance based on the output results of radar signal cross-correlation analysis unit 10 and lidar signal cross-correlation analysis unit 14 is shown below. Figure 5 As shown. Example

[0019] like Figure 4As shown, this embodiment provides a distributed radar and lidar system based on a chaotic optical comb, including a laser 1, an optical circulator 2, a wavelength division multiplexer 3, and an optical fiber. n 4. Optical coupler; 5. Photodetector; 6. Electrical coupler; 7. Transmitting antenna; 8. Receiving antenna; 9. Radar signal cross-correlation analysis unit; 10. Optical circulator; 11. Collimator; 12. Photodetector; 13. and lidar signal cross-correlation analysis unit; 14.

[0020] The optical signal output from laser 1 is fed back to laser 1 via optical circulator 2, generating a chaotic optical comb signal, which is then output through optical circulator 2. This chaotic optical comb signal is then generated by wavelength division multiplexer 3. N A single chaotic optical signal of different wavelengths. (The sentence is incomplete and requires further context.) n wavelengths ( n It is an integer, and 1 ≤ n ≤ N Taking a chaotic optical signal as an example, the signal passes through the corresponding optical fiber. n Transmitted to the n The first radar and lidar module. In this module, optical coupler 5 will receive the input from the first... n The chaotic optical signal of wavelength is split into two paths, which are used for the ... n The radar transceiver module and the first n One LiDAR transceiver module.

[0021] In the radar transceiver module, the chaotic optical signal is converted into an electrically chaotic signal by a photodetector 6, and then split into three branches by an electrocoupler 7: the output signal of branch 1 is used as the radar detection signal, the output signal of branch 2 is used as the radar reference signal, and the output signal of branch 3 is used as the lidar reference signal. The radar detection signal output from branch 1 is used to detect the radar target via the transmitting antenna 8, and its echo is received by the receiving antenna 9. The radar echo signal and the radar reference signal output from branch 2 are input to the radar signal cross-correlation analysis unit 10. By calculating the cross-correlation result and determining the target distance based on the pulse delay position, the microwave sensing function is realized.

[0022] In the lidar transceiver module, the chaotic light signal first passes through the optical circulator 11, and then through the collimator 12 to detect the lidar target. The echo signal reflected from the target passes through the collimator 12 and the optical circulator 11 in sequence, and is then converted into a lidar electrical echo signal by the photodetector 13. The lidar reference signal output from branch 3, together with the lidar electrical echo signal, enters the lidar signal cross-correlation analysis unit 14. By calculating the cross-correlation result, the pulse delay position is obtained, and the target distance is determined accordingly, thus realizing the optical sensing function.

[0023] The schematic diagram illustrating the determination of target distance based on the output results of radar signal cross-correlation analysis unit 10 and lidar signal cross-correlation analysis unit 14 is shown below. Figure 5 As shown.

[0024] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to the embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A distributed radar and lidar system based on chaotic optical combs, characterized in that, The system comprises a chaotic optical comb signal generation module, a wavelength division multiplexer, N an optical fiber, and N a radar and lidar module. The chaotic optical comb signal generated by the chaotic optical comb signal generation module is divided into N single chaotic optical signals of different wavelengths in a wavelength division multiplexer; N The single chaotic optical signals of different wavelengths are transmitted to N radar and lidar modules located at different spatial positions through N optical fibers respectively, realizing spatially distributed allocation of signals; The radar and lidar module comprises an optical coupler, a radar transceiver module and a lidar transceiver module; the optical coupler divides the input single chaotic light signal into two paths, which are respectively sent into the radar transceiver module and the lidar transceiver module, so as to realize the sharing of the same light signal on the radar and lidar module. After the single chaotic light signal is photoelectrically converted into an electric chaotic signal by the photoelectric detector 1, the electric chaotic signal is divided into three branches by an electric coupler, wherein the output signal of the first branch is used as a radar detection signal, the output signal of the second branch is used as a radar reference signal, and the output signal of the third branch is used as a lidar reference signal, so as to realize the same-source sharing of the radar and lidar reference signals.

2. The chaos-optical comb based distributed radar and lidar system of claim 1, wherein, In the radar transceiver module, the radar detection signal output by the electric coupler branch 1 is used to detect a target through a radar transmitting module, and a radar echo signal is received through a radar receiving module; the radar reference signal output by the electric coupler branch 2 and the received radar echo signal are processed through a radar signal cross-correlation analysis unit, and the target distance is determined according to the pulse time delay position in the cross-correlation result.

3. The chaos-optical comb based distributed radar and lidar system of claim 2, wherein, In the lidar transceiver module, the single chaotic light signal is used as a lidar detection signal to detect a target through a lidar transmitting module, and a lidar echo signal is received through a lidar receiving module; the received lidar echo signal is converted into a lidar electric echo signal by a photoelectric detector 2; the lidar reference signal from the electric coupler branch 3 and the lidar electric echo signal converted by the photoelectric detector 2 are processed through a lidar signal cross-correlation analysis unit, and the target distance is determined according to the pulse time delay position in the cross-correlation result.

4. The chaos-optical comb based distributed radar and lidar system of claim 1, wherein, Radar detects the distance of the target L 1= cτ 1 / 2, laser radar detects the distance of the target L 2= cτ 2 / 2, wherein c is the speed of light in vacuum, τ 1 is the pulse time delay position output by the radar signal cross-correlation analysis unit, τ 2 is the pulse time delay position output by the laser radar signal cross-correlation analysis unit.

5. The chaos-optical comb based distributed radar and lidar system of claim 1, wherein, The chaotic light comb signal generation module is realized by a microcavity optical comb or a laser self-injection locking method.

6. The chaos-optical comb based distributed radar and lidar system of claim 1, wherein, The chaotic light comb signal generation module has mutual orthogonal characteristics between each chaotic comb tooth, and no correlation.

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