A radar detection system with adaptive adjustment of operating mode

Abstract

This invention relates to a radar detection system with adaptive adjustment of operating modes, belonging to the field of radar detection technology. It solves the problem of low detection performance in existing radar systems due to limited detection performance at different distances and the inability to fully utilize the advantages of various radar types. The system includes: a microwave radar module, which receives a first laser and a second laser emitted from a beam splitter; modulates the first laser to generate a microwave radar transmission signal and transmits it to the target; modulates the second laser and transmits it to a feature generation module and a control module; a single-photon lidar module, which receives a third laser, generates a single-photon laser pulse and transmits it; receives the single-photon laser pulse echo signal and transmits it to the feature generation module and the control module; the feature generation module processes the intermediate frequency echo signal and the single-photon lidar signal to generate feature parameters of the target; and controls the operation of the microwave radar module and the single-photon lidar module based on the signal-to-noise ratio and range data.

Description

Technical Field

[0001] This invention relates to the field of radar detection technology, and in particular to a radar detection system with adaptive adjustment of operating mode. Background Technology

[0002] With the rapid development of modern technology, radar technology has been widely used in many fields, such as autonomous driving, aerospace, and meteorological monitoring. These applications place extremely stringent requirements on the performance of radar systems, making high-resolution detection a key direction for the development of radar technology.

[0003] In the traditional radar technology system, microwave radar and single-photon lidar each have their advantages and disadvantages. While microwave radar has certain capabilities in target range and velocity detection, its resolution and sensitivity are limited at long distances due to factors such as signal attenuation. Although single-photon lidar has significant advantages in high-resolution detection, it faces challenges in short-range detection scenarios, including high signal processing complexity and relatively high cost.

[0004] Furthermore, existing radar systems lack effective mechanisms for adaptively adjusting operating modes when dealing with targets at different distances and complex and changing environmental conditions. Moreover, a mature and efficient method for fusing data collected by different types of radars has not yet been developed, making it difficult to fully leverage the advantages of each type of radar and thus limiting the improvement of the overall system detection performance. Summary of the Invention

[0005] Based on the above analysis, the embodiments of the present invention aim to provide a radar detection system with adaptive adjustment of operating mode, in order to solve the problem of low radar system detection performance caused by the limited detection performance of existing radar systems at different distances and the inability to give full play to the advantages of various radars.

[0006] This invention provides a radar detection system with adaptive adjustment of operating mode, comprising:

[0007] The laser generation module is used to output the first and second laser beams to the microwave radar module, and to output the third laser beam to the single-photon lidar module.

[0008] The microwave radar module is used to receive the first and second laser beams emitted by the beam splitter, modulate the first laser beam with radio frequency signals to generate a microwave radar transmission signal and transmit it to the target; it is also used to receive microwave radar echo signals, and modulate the second laser beam with radio frequency signals to generate an intermediate frequency echo signal, which is then transmitted to the feature generation module and the control module.

[0009] The single-photon lidar module is used to receive the third laser beam emitted by the beam splitter, generate a single-photon laser pulse based on the third laser beam, and emit it; it is also used to receive the single-photon laser pulse echo signal and convert it into an electrical signal before transmitting it to the feature generation module and the control module.

[0010] The feature generation module is used to process the received intermediate frequency echo signal from the microwave radar module and the electrical signal from the single-photon lidar module to generate the feature parameters of the target.

[0011] The sensor unit collects preliminary distance data between the target and the radar system, and transmits the distance data to the control module;

[0012] The control module is used to calculate the signal-to-noise ratio of the microwave radar echo signal and the single-photon laser pulse echo signal, and to control the operation of the microwave radar module and the single-photon laser radar module based on the signal-to-noise ratio and distance data.

[0013] As a further improvement to this application, controlling the operation of the microwave radar module and the single-photon lidar module based on the signal-to-noise ratio and preliminary distance data includes:

[0014] When the preliminary distance data is less than the first distance threshold and the signal-to-noise ratio of the microwave radar echo signal is higher than the first preset signal-to-noise ratio threshold, the microwave radar module is controlled to work independently.

[0015] When the preliminary distance data is greater than the second distance threshold and the signal-to-noise ratio of the single-photon laser pulse echo signal is higher than the second preset signal-to-noise ratio threshold, the single-photon lidar module is controlled to work independently.

[0016] In other cases, the control microwave radar module and the single-photon lidar module operate simultaneously.

[0017] As a further improvement of this application, the microwave radar module includes: a radio frequency signal generator, a first optoelectronic modulator, a second optoelectronic modulator, a first optoelectronic conversion unit, a second optoelectronic conversion unit, and a transceiver unit;

[0018] The radio frequency signal generator is used to generate a first radio frequency signal and a programmable radio frequency signal and send them to a first optoelectronic modulator; it is also used to generate a second radio frequency signal and send it to a second optoelectronic modulator.

[0019] The first optoelectronic modulator modulates the first laser based on the programmable radio frequency signal and the first radio frequency signal, and sends the modulated optical signal to the first optoelectronic conversion unit for optoelectronic conversion to obtain a microwave radar transmission signal, which is then transmitted by the transceiver unit.

[0020] The transceiver unit receives microwave radar echo signals and transmits them to the second optoelectronic modulator.

[0021] The second optoelectronic modulator modulates the second laser based on the microwave radar echo signal and the second radio frequency signal to generate a modulated optical signal, which is then sent to the second optoelectronic conversion unit for optoelectronic conversion to obtain an intermediate frequency echo signal. The intermediate frequency echo signal is then transmitted to the feature generation module.

[0022] As a further improvement to this application, the radio frequency signal generator includes: a waveform generator, a radio frequency source, a mixer, and a first bandpass filter;

[0023] A radio frequency (RF) source is used to generate a first RF signal that is transmitted to a mixer; and to generate a second RF signal that is transmitted to a second opto-modulator.

[0024] A waveform generator is used to generate intermediate frequency signals and transmit them to a mixer.

[0025] A mixer mixes the first radio frequency signal and the intermediate frequency signal to generate a programmable radio frequency signal, which is then transmitted to a first bandpass filter.

[0026] The first bandpass filter is used to filter the programmable radio frequency signal and transmit the filtered programmable radio frequency signal to the first modulation unit.

[0027] As a further improvement to this application, the single-photon lidar module includes:

[0028] The third component includes an optoelectronic modulator, a single-photon amplifier, a photodetector, an optical transmitting system, and an optical receiving system.

[0029] The third optoelectronic modulator is used to receive the third laser beam after beam splitting, modulate the third laser beam to generate a single-photon laser pulse and transmit it to the optical amplifier.

[0030] A single-photon amplifier is used to amplify the single-photon laser pulse and transmit the amplified single-photon laser pulse to an optical emission system for emission.

[0031] An optical receiving system receives single-photon laser pulse echo signals and transmits them to a photodetector.

[0032] A single-photon photodetector is used to convert the echo signal of a single-photon laser pulse into an electrical signal and transmit it to the feature generation module.

[0033] As a further improvement of this application, the first photoelectric conversion unit includes: a first optical amplifier, used to amplify the modulated optical signal sent by the first photoelectric modulator and then transmit it to the first optical filter;

[0034] The first optical filter is used to filter the amplified optical signal before transmitting it to the first photodetector.

[0035] The first photodetector is used to convert the filtered optical signal into a microwave radar transmission signal and transmit it to the transceiver unit for transmission.

[0036] As a further improvement to this application, the second photoelectric conversion unit includes:

[0037] Second optical filter, second photodetector, second bandpass filter;

[0038] The second optical filter is used to receive the optical signal generated by the second photoelectric modulator, filter the optical signal and then transmit it to the second photodetector.

[0039] The second photodetector is used to convert the filtered optical signal into an intermediate frequency echo signal and transmit it to the second bandpass filter.

[0040] The second bandpass filter is used to filter the intermediate frequency echo signal and transmit it to the feature generation module.

[0041] As a further improvement to this application, the characteristic parameters of the target are generated by processing the received intermediate frequency echo signal from the microwave radar module and the electrical signal from the single-photon lidar module, including:

[0042] The first distance information obtained based on the intermediate frequency echo signal and the second distance information obtained based on the laser pulse electrical signal are weighted and averaged to obtain the target distance information as shown in the calculation formula (1);

[0043] R=βR1+γR2 (1)

[0044] Where R represents the target distance information, R1 represents the first distance information, R2 represents the second distance information, and β and γ represent the distance weights.

[0045] As a further improvement of this application, the first distance information is obtained based on the intermediate frequency echo signal as shown in the calculation formula (2);

[0046]

[0047] Where R1 represents the first distance information, c represents the speed of light, t1 represents the arrival time of the microwave radar echo pulse, and t 01 The transmission time of the microwave radar signal is given; the second distance information obtained based on the laser pulse electrical signal is shown in calculation formula (3);

[0048]

[0049] Where R2 represents the second distance information, t2 represents the arrival time of the single-photon laser pulse, and t 02 This represents the emission time of a single-photon laser pulse.

[0050] As a further improvement to this application, the intermediate frequency echo signal is calculated as shown in equation (4);

[0051] s(t)=A1cos2πf0t+πkt 2 (4)

[0052] Where A1 is the amplitude of the intermediate frequency echo signal, t is the time variable, f0 is the center frequency of the intermediate frequency echo signal, and k is the modulation coefficient;

[0053] The laser pulse electrical signal is calculated as shown in equation (10);

[0054] s(t)=A3cos(2πf LP t+Δθ) (10)

[0055] Where A3 is the amplitude of the laser pulse electrical signal, t is the time variable, and f LP The oscillation frequency of the laser pulse electrical signal, and the phase shift of the laser pulse electrical signal Δθ.

[0056] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0057] 1. This invention sets different operating modes. When the initial target distance data is less than a first distance threshold and the signal-to-noise ratio (SNR) of the microwave radar echo signal is higher than a first preset SNR threshold, the microwave radar module is controlled to operate independently, leveraging its short-range detection advantage. When the initial target distance data is greater than a second distance threshold and the SNR of the single-photon laser pulse echo signal is higher than a second preset SNR threshold, the single-photon lidar module is controlled to operate independently, utilizing its long-range high-resolution characteristics. In other cases, both operate simultaneously, optimizing detection performance at different distances.

[0058] 2. The control module of this invention can intelligently control the working state of the microwave radar module and the single-photon laser radar module based on the signal-to-noise ratio of the microwave radar echo signal and the single-photon laser pulse echo signal, as well as the preliminary distance data. This enables the radar system to adaptively adjust the detection mode according to the actual situation, thereby improving the system's adaptability and detection performance.

[0059] 3. The feature generation module of the present invention processes the intermediate frequency echo signal of the microwave radar module and the electrical signal of the single-photon lidar module. By performing weighted averaging on the first distance information obtained based on the intermediate frequency echo signal and the second distance information obtained based on the laser pulse electrical signal, more accurate target distance information is obtained, which effectively improves the fusion processing capability of different radar data and thus improves the overall detection performance of the system.

[0060] 4. The microwave radar module of this invention constructs a new microwave-laser composite detection architecture based on microwave photonics technology, in which all components except the microwave antenna / optical lens and TR components are uniformly processed in the photonic domain. This all-optical processing architecture does not require a parallel or multiplexed high-frequency electronic architecture, has a simpler system structure, uses an arbitrary waveform generator to generate a programmable intermediate frequency signal, and generates radar signals through photonic frequency conversion methods, achieving higher bandwidth, flexibility and coherence.

[0061] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0062] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0063] Figure 1 This is a schematic diagram of a radar detection system with adaptive adjustment of operating mode, provided as an embodiment of the present invention. Detailed Implementation

[0064] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0065] A specific embodiment of the present invention discloses a radar detection system with adaptive adjustment of operating mode, comprising:

[0066] The laser generation module is used to output the first and second laser beams to the microwave radar module, and to output the third laser beam to the single-photon lidar module.

[0067] The microwave radar module is used to receive the first and second laser beams emitted by the beam splitter, modulate the first laser beam with radio frequency signals to generate a microwave radar transmission signal and transmit it to the target; it is also used to receive microwave radar echo signals, and modulate the second laser beam with radio frequency signals to generate an intermediate frequency echo signal, which is then transmitted to the feature generation module and the control module.

[0068] The single-photon lidar module is used to receive the third laser beam emitted by the beam splitter, generate a single-photon laser pulse based on the third laser beam, and emit it; it is also used to receive the single-photon laser pulse echo signal and convert it into an electrical signal before transmitting it to the feature generation module and the control module.

[0069] The feature generation module is used to process the received intermediate frequency echo signal from the microwave radar module and the electrical signal from the single-photon lidar module to generate the feature parameters of the target.

[0070] The sensor unit collects preliminary distance data between the target and the radar system, and transmits the distance data to the control module;

[0071] The control module is used to calculate the signal-to-noise ratio of the microwave radar echo signal and the single-photon laser pulse echo signal, and to control the operation of the microwave radar module and the single-photon laser radar module based on the signal-to-noise ratio and distance data.

[0072] like Figure 1 As shown, a laser generation module outputs a first and second laser beam to a microwave radar module, and a third laser beam to a single-photon lidar module. The laser generation module includes a laser 1 and a beam splitter 2. The continuous laser beam generated by laser 1 is split into multiple beams by beam splitter 2, which are then transmitted to the microwave radar module and the single-photon lidar module respectively. Beam splitter 2 is an optical element used to split the laser beam emitted by laser 1 into three beams, with the first and second beams transmitted to the microwave radar module and the third beam transmitted to the single-photon lidar module.

[0073] The microwave radar module receives the first and second laser beams emitted by beam splitter 2. It modulates the first laser beam using radio frequency signals to generate a microwave radar transmit signal, which is then transmitted to the target. It also receives microwave radar echo signals and modulates the second laser beam using the microwave radar echo signal and radio frequency signals to generate an intermediate frequency echo signal, which is then transmitted to the feature generation module and the control module.

[0074] Specifically, the microwave radar module includes: a radio frequency signal generator, a first optoelectronic modulator, a second optoelectronic modulator, a first optoelectronic conversion unit, a second optoelectronic conversion unit, and a transceiver unit;

[0075] The radio frequency signal generator is used to generate a first radio frequency signal and a programmable radio frequency signal and send them to a first optoelectronic modulator; it is also used to generate a second radio frequency signal and send it to a second optoelectronic modulator.

[0076] The radio frequency (RF) signal generator is used to generate RF signals for radar detection. The RF signal generator includes: a waveform generator 4, an RF source 3, a mixer 5, and a first bandpass filter 6. The RF source 3 generates a first RF signal which is transmitted to the mixer 5, and generates a second RF signal which is transmitted to the second optoelectronic modulator 13 for modulating a second laser beam.

[0077] Waveform generator 4 is used to generate intermediate frequency (IF) signals and transmit them to mixer 5. The IF signal is a fixed frequency signal used for signal processing and modulation in the radar system, with a frequency between that of radio frequency (RF) signals and baseband signals.

[0078] Mixer 5 mixes the first radio frequency signal and the intermediate frequency signal to generate a programmable radio frequency signal, which is then transmitted to the first bandpass filter 6. The programmable radio frequency signal can be programmed as needed to adapt to different detection conditions and target characteristics.

[0079] The first bandpass filter 6 is used to filter the programmable radio frequency signal to ensure that the frequency characteristics of the signal meet the system requirements. The filtered programmable radio frequency signal is then transmitted to the first modulation unit.

[0080] The first optoelectronic modulator 7 modulates the first laser beam based on the programmable radio frequency signal and the first radio frequency signal, and sends the modulated optical signal to the first optoelectronic conversion unit for optoelectronic conversion to obtain a microwave radar transmission signal, which is then transmitted by the transceiver unit. The second optoelectronic modulator 13 modulates the second laser beam based on the microwave radar echo signal and the second radio frequency signal to generate a modulated optical signal, which is then sent to the second optoelectronic conversion unit for optoelectronic conversion to obtain an intermediate frequency echo signal, which is then transmitted to the control and acquisition processing module 29.

[0081] The first optoelectronic modulator 7 modulates the first laser beam with a programmable radio frequency signal generated by the radio frequency signal generator and a first radio frequency signal, changing the phase or amplitude of the laser to carry the information required for radar detection. The second optoelectronic modulator 13 receives the target-reflected microwave radar echo signal from the transceiver unit and modulates the second laser beam together with the second radio frequency signal, changing the phase or amplitude of the laser. Modulation is the process of encoding information onto a carrier wave in a radar signal. In the optoelectronic modulator, the characteristics of the laser, such as amplitude, frequency, or phase, are changed to carry the information to be transmitted.

[0082] Furthermore, the first photoelectric conversion unit includes:

[0083] The first optical amplifier 8 amplifies the modulated optical signal sent by the first photoelectric modulator 7 before transmitting it to the first optical filter. The first optical amplifier 8 amplifies the modulated optical signal to increase its intensity.

[0084] The first optical filter 9 is used to filter the amplified optical signal before transmitting it to the first photodetector, removing unwanted frequency components to improve signal quality.

[0085] The first photodetector 10 is used to convert the filtered optical signal into a corresponding electrical signal, namely the microwave radar transmission signal, and transmit the microwave radar transmission signal to the transceiver unit for transmission.

[0086] The transceiver unit includes a TR component 11 and an antenna 12. The TR component 11 includes a transmitter and a receiver. In transmit mode, the TR component 11 transmits microwave radar signals to the target via the antenna 12. In receive mode, the TR component 11 receives echo signals reflected from the target.

[0087] The second photoelectric conversion unit includes: a second optical filter 14, a second photodetector 15, and a second bandpass filter 16.

[0088] The second optical filter 14 is used to receive the optical signal modulated by the second photoelectric modulator 13, filter the optical signal to remove unwanted frequency components or noise, and transmit the filtered signal to the second photodetector.

[0089] The second photodetector 15 is used to convert the filtered optical signal into an electrical signal, namely an intermediate frequency echo signal, and transmit it to the second bandpass filter 16.

[0090] The second bandpass filter 16 is used to further filter the intermediate frequency echo signal to extract useful signal components, remove unwanted frequencies or noise, and transmit the signal to the control and acquisition processing module 29.

[0091] The microwave radar transmits signals as shown in calculation formula (1);

[0092] ω Radar =m·ω RF1 -n·ω RF2 -m·[ω IF -BW / 2+BW·t / T]

[0093] Where, ω Radar ω is the angular frequency of the microwave radar transmitted signal. RF1 Let ω be the angular frequency of the first radio frequency signal. RF2 ω is the angular frequency of the second radio frequency signal. IF ω is the angular frequency of the programmable radio frequency signal, m and n are the laser modulation order, BW is the bandwidth of the programmable radio frequency signal, T is the pulse width of the programmable radio frequency signal, and t is the modulation time.

[0094] The intermediate frequency echo signal is shown in calculation formula (2);

[0095] ω′ IF =k·ω RF3 -ω′ Radar

[0096] Where, ω RF3 Let ω' be the angular frequency of the third radio frequency signal. Radar Let ω′ be the angular frequency of the microwave radar echo signal. IF ω is the angular frequency of the intermediate frequency echo signal, and k is the laser modulation order.

[0097] Furthermore, the single-photon lidar module includes: a third optoelectronic modulator 17, a second optical amplifier 18, a third photodetector 19, an optical transmitting system 20, and an optical receiving system 21.

[0098] The third optoelectronic modulator 17 receives the third laser beam after beam splitting, modulates the third laser beam to generate single-photon laser pulses, and transmits them to the second optical amplifier. The third optoelectronic modulator 17 receives the third laser beam from the beam splitter 2, performs electro-optic effects on the third laser beam to generate the required pulse sequence, and generates single-photon level laser pulses. Each single-photon laser pulse contains only one photon, which has the characteristics of high time resolution and sensitivity, and can accurately measure the arrival time of photons in a very short time.

[0099] The second optical amplifier 18 is used to amplify the single-photon laser pulse and transmit the amplified single-photon laser pulse to the optical emission system 20 for emission. The optical emission system 20 includes lenses or other optical elements for focusing and directional emission of the laser pulse toward the target area.

[0100] The optical receiving system 21 receives the echo signal of a single-photon laser pulse and transmits it to the third photodetector 19. The optical receiving system 21 includes a receiving lens or optical antenna for collecting the scattered laser pulse and focusing it onto the third photodetector 29.

[0101] The third photodetector 19 is used to convert the single-photon laser pulse echo signal into an electrical signal and transmit it to the control and acquisition processing module. The sensitivity of the third photodetector 19 needs to be set to be able to detect signals at the single photon level. The converted electrical signal is transmitted to the control and acquisition processing module 29.

[0102] Furthermore, the sensor unit can be selected from sensors such as laser rangefinders, ultrasonic sensors, or vision-based distance measurement sensors to perform preliminary distance measurements between the target and the radar system. The preliminary distance data is the distance information between the target and the radar system obtained by the sensor unit. Based on the preliminary distance data and the signal-to-noise ratio of the microwave radar echo signal and the single-photon laser pulse echo signal, the control module determines the operating mode of the microwave radar module and the single-photon lidar module.

[0103] The control module is used to calculate the signal-to-noise ratio of the microwave radar echo signal and the single-photon laser pulse echo signal, and to control the operation of the microwave radar module and the single-photon laser radar module based on the signal-to-noise ratio and distance data.

[0104] Signal-to-noise ratio (SNR) can be calculated using power spectrum estimation. A Fast Fourier Transform (FFT) is performed on microwave radar echo signals and single-photon laser pulse echo signals to convert the time-domain signals into frequency-domain signals. The FFT decomposes the signal into power spectral densities of different frequency components, and the power spectrum is obtained by calculating the square of the amplitude of the frequency-domain signal. Signal energy is typically concentrated in certain frequency bands, while noise is more uniformly distributed in the frequency domain. Therefore, the power of the main signal frequency bands can be summed to obtain the signal power, and the power of the remaining frequency bands can be considered as noise power. The ratio of signal power to noise power is the signal-to-noise ratio (SNR).

[0105] Furthermore, controlling the operation of the microwave radar module and the single-photon lidar module based on the signal-to-noise ratio and preliminary distance data includes:

[0106] When the preliminary distance data is less than the first distance threshold and the signal-to-noise ratio of the microwave radar echo signal is higher than the first preset signal-to-noise ratio threshold, the microwave radar module is controlled to work independently.

[0107] When the preliminary distance data is greater than the second distance threshold and the signal-to-noise ratio of the single-photon laser pulse echo signal is higher than the second preset signal-to-noise ratio threshold, the single-photon lidar module is controlled to work independently.

[0108] In other cases, the control microwave radar module and the single-photon lidar module operate simultaneously.

[0109] The first distance threshold, the second distance threshold, the first preset signal-to-noise ratio threshold, and the second preset signal-to-noise ratio threshold can be set according to the performance parameters of the microwave radar module and the single-photon lidar module. Microwave radar typically has high resolution and strong anti-interference capabilities in the short to medium range. However, as the detection distance increases, the microwave radar signal attenuates significantly, leading to a weakening of the echo signal strength, a decrease in the signal-to-noise ratio, and a reduction in long-range detection accuracy. Single-photon lidar has extremely high sensitivity, making it particularly suitable for long-range detection. It can detect very weak echo signals. For small targets or low-reflectivity targets at long distances, single-photon lidar can receive and process single-photon level signals, achieving long-range detection.

[0110] The first distance threshold can be set considering the optimal operating range of the microwave radar, based on its effective detection range and resolution. The second distance threshold should be set considering the optimal operating range of the single-photon lidar. Beyond this range, the advantages of the single-photon lidar become apparent. Typically, the second distance threshold can be set at the distance where the single-photon lidar begins to outperform the microwave radar. Beyond the second distance threshold, the single-photon lidar module operates independently, leveraging its high sensitivity and long-range detection capabilities to effectively detect distant targets.

[0111] The first and second preset signal-to-noise ratio (SNR) thresholds need to be set based on the noise characteristics and signal strength variation patterns of the microwave radar module and the single-photon lidar module. Signal strength and noise levels at different distances can be experimentally tested to plot the SNR versus distance curve, allowing for the selection of appropriate values. Above these thresholds, the reliability and detection accuracy of the microwave radar module and the single-photon lidar module are sufficiently high.

[0112] The feature generation module is used to process the received intermediate frequency echo signal from the microwave radar module and the electrical signal from the single-photon lidar module to generate the feature parameters of the target.

[0113] The characteristic parameters of the target are generated by processing the received intermediate frequency echo signal from the microwave radar module and the electrical signal from the single-photon lidar module, including:

[0114] A. When the microwave radar module and the single-photon lidar module work simultaneously, the first distance information obtained based on the intermediate frequency echo signal and the second distance information obtained based on the laser pulse electrical signal are weighted and averaged to obtain the target distance information as shown in the calculation formula (3).

[0115] R=βR1+γR2 (3)

[0116] Where R represents the target distance information, R1 represents the first distance information, R2 represents the second distance information, and β and γ represent the distance weights.

[0117] The first distance information is obtained based on the intermediate frequency echo signal as shown in the calculation formula (4);

[0118]

[0119] Where R1 represents the first distance information, c represents the speed of light, t1 represents the arrival time of the microwave radar echo pulse, and t 01 The transmission time of the microwave radar signal is given; the second distance information obtained based on the laser pulse electrical signal is shown in calculation formula (5);

[0120]

[0121] Where R2 represents the second distance information, t2 represents the arrival time of the single-photon laser pulse, and t 02 This represents the emission time of a single-photon laser pulse.

[0122] The target velocity obtained based on the intermediate frequency echo signal is used as the target's velocity information.

[0123] B. When the microwave radar module operates alone, the target distance and velocity information are obtained only based on the intermediate frequency echo signal.

[0124] The target distance information is shown in the calculation formula (4).

[0125] The target velocity information obtained from the intermediate frequency echo signal includes:

[0126] The Doppler frequency shift is obtained by performing spectral analysis on the intermediate frequency echo signal;

[0127] The target velocity information is shown in the calculation formula (6);

[0128]

[0129] Where λ1 is the wavelength of the microwave radar transmitted signal, and Δf1 is the Doppler frequency shift.

[0130] C. When the single-photon lidar module works alone, the target distance information is obtained only based on the laser pulse electrical signal. The target distance information is shown in the calculation formula (5).

[0131] The laser pulse electrical signal is shown in calculation formula (7);

[0132] s(t)=A3cos(2πf LP t+Δθ) (7)

[0133] Where A3 is the amplitude of the laser pulse electrical signal, t is the time variable, and f LP The oscillation frequency of the laser pulse electrical signal, and the phase shift of the laser pulse electrical signal Δθ.

[0134] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0135] By setting different working modes, when the initial target distance data is less than the first distance threshold and the signal-to-noise ratio of the microwave radar echo signal is higher than the first preset signal-to-noise ratio threshold, the microwave radar module is controlled to work independently to give full play to its short-range detection advantage; when the initial target distance data is greater than the second distance threshold and the signal-to-noise ratio of the single-photon laser pulse echo signal is higher than the second preset signal-to-noise ratio threshold, the single-photon lidar module is controlled to work independently to utilize its long-range high-resolution characteristics. In other cases, both operate simultaneously, optimizing detection performance at different distances. The control module can intelligently control the operating status of the microwave radar module and the single-photon laser pulse echo signal based on the signal-to-noise ratio and preliminary distance data, enabling the radar system to adaptively adjust the detection mode according to the actual situation, thus improving the system's adaptability and efficiency. The feature generation module processes the intermediate frequency echo signal from the microwave radar module and the electrical signal from the single-photon laser pulse module. By performing weighted averaging on the first distance information obtained from the intermediate frequency echo signal and the second distance information obtained from the laser pulse electrical signal, more accurate target distance information is obtained, effectively improving the fusion processing capability of different radar data, thereby enhancing the overall detection performance of the system.

[0136] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0137] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A radar detection system with adaptive adjustment of operating mode, characterized in that, include: The laser generation module is used to output the first and second laser beams to the microwave radar module, and to output the third laser beam to the single-photon lidar module. The microwave radar module is used to receive the first and second laser beams emitted by the beam splitter, modulate the first laser beam with radio frequency signals to generate a microwave radar transmission signal and transmit it to the target; it is also used to receive microwave radar echo signals, and modulate the second laser beam with radio frequency signals to generate an intermediate frequency echo signal, which is then transmitted to the feature generation module and the control module. The single-photon lidar module is used to receive the third laser beam emitted by the beam splitter, generate a single-photon laser pulse based on the third laser beam, and emit it; it is also used to receive the single-photon laser pulse echo signal and convert it into an electrical signal before transmitting it to the feature generation module and the control module. The feature generation module is used to process the received intermediate frequency echo signal from the microwave radar module and the electrical signal from the single-photon lidar module to generate the feature parameters of the target. The sensor unit collects preliminary distance data between the target and the radar system, and transmits the distance data to the control module; The control module is used to calculate the signal-to-noise ratio of the microwave radar echo signal and the single-photon laser pulse echo signal, and to control the operation of the microwave radar module and the single-photon laser radar module based on the signal-to-noise ratio and distance data.

2. The system according to claim 1, characterized in that, Controlling the operation of the microwave radar module and the single-photon lidar module based on the signal-to-noise ratio and preliminary distance data includes: When the preliminary distance data is less than the first distance threshold and the signal-to-noise ratio of the microwave radar echo signal is higher than the first preset signal-to-noise ratio threshold, the microwave radar module is controlled to work independently. When the preliminary distance data is greater than the second distance threshold and the signal-to-noise ratio of the single-photon laser pulse echo signal is higher than the second preset signal-to-noise ratio threshold, the single-photon lidar module is controlled to work independently. In other cases, the control microwave radar module and the single-photon lidar module operate simultaneously.

3. The system according to claim 2, characterized in that, When the microwave radar module and the single-photon lidar module operate simultaneously, the characteristic parameters of the target are generated by processing the received intermediate frequency echo signal from the microwave radar module and the electrical signal from the single-photon lidar module. The first distance information obtained based on the intermediate frequency echo signal and the second distance information obtained based on the laser pulse electrical signal are weighted and averaged to obtain the target distance information as shown in the calculation formula (1); R=βR1+γR2 (1) Where R is the target distance information, R1 is the first distance information, R2 is the second distance information, and β and γ are the distance weights; The target velocity obtained based on the intermediate frequency echo signal is used as the target's velocity information.

4. The system according to claim 3, characterized in that, The first distance information is obtained based on the intermediate frequency echo signal as shown in the calculation formula (2); Where R1 represents the first distance information, c represents the speed of light, t1 represents the arrival time of the microwave radar echo pulse, and t 01 The transmission time of the microwave radar signal is given; the second distance information obtained based on the laser pulse electrical signal is shown in calculation formula (3); Where R2 represents the second distance information, t2 represents the arrival time of the single-photon laser pulse, and t 02 This represents the emission time of a single-photon laser pulse.

5. The system according to claim 3, characterized in that, The intermediate frequency echo signal is calculated as shown in equation (4); s(t)=A1cos2πf0t+πkt 2 (4) Where A1 is the amplitude of the intermediate frequency echo signal, t is the time variable, f0 is the center frequency of the intermediate frequency echo signal, and k is the modulation coefficient; The laser pulse electrical signal is calculated as shown in equation (5); s(t)=A3cos(2πf LP t+Δθ) (5) Where A3 is the amplitude of the laser pulse electrical signal, t is the time variable, and f LP The oscillation frequency of the laser pulse electrical signal, and the phase shift of the laser pulse electrical signal Δθ.

6. The system according to claim 1, characterized in that, The microwave radar module includes: a radio frequency signal generator, a first optoelectronic modulator, a second optoelectronic modulator, a first optoelectronic conversion unit, a second optoelectronic conversion unit, and a transceiver unit; The radio frequency signal generator is used to generate a first radio frequency signal and a programmable radio frequency signal and send them to a first optoelectronic modulator; it is also used to generate a second radio frequency signal and send it to a second optoelectronic modulator. The first optoelectronic modulator modulates the first laser based on the programmable radio frequency signal and the first radio frequency signal, and sends the modulated optical signal to the first optoelectronic conversion unit for optoelectronic conversion to obtain a microwave radar transmission signal, which is then transmitted by the transceiver unit. The transceiver unit receives microwave radar echo signals and transmits them to the second optoelectronic modulator. The second optoelectronic modulator modulates the second laser based on the microwave radar echo signal and the second radio frequency signal to generate a modulated optical signal, which is then sent to the second optoelectronic conversion unit for optoelectronic conversion to obtain an intermediate frequency echo signal. The intermediate frequency echo signal is then transmitted to the feature generation module.

7. The system according to claim 6, characterized in that, The radio frequency signal generator includes: a waveform generator, a radio frequency source, a mixer, and a first bandpass filter; A radio frequency (RF) source is used to generate a first RF signal that is transmitted to a mixer; and to generate a second RF signal that is transmitted to a second opto-modulator. A waveform generator is used to generate intermediate frequency signals and transmit them to a mixer. A mixer mixes the first radio frequency signal and the intermediate frequency signal to generate a programmable radio frequency signal, which is then transmitted to a first bandpass filter. The first bandpass filter is used to filter the programmable radio frequency signal and transmit the filtered programmable radio frequency signal to the first modulation unit.

8. The system according to claim 1, characterized in that, The single-photon lidar module includes: The third component includes an optoelectronic modulator, a single-photon amplifier, a photodetector, an optical transmitting system, and an optical receiving system. The third optoelectronic modulator is used to receive the third laser beam after beam splitting, modulate the third laser beam to generate a single-photon laser pulse and transmit it to the optical amplifier. A single-photon amplifier is used to amplify the single-photon laser pulse and transmit the amplified single-photon laser pulse to an optical emission system for emission. An optical receiving system receives single-photon laser pulse echo signals and transmits them to a photodetector. A single-photon photodetector is used to convert the echo signal of a single-photon laser pulse into an electrical signal and transmit it to the feature generation module.

9. The system according to claim 8, characterized in that, The first photoelectric conversion unit includes: a first optical amplifier, used to amplify the modulated optical signal sent by the first photoelectric modulator and then transmit it to the first optical filter; The first optical filter is used to filter the amplified optical signal before transmitting it to the first photodetector. The first photodetector is used to convert the filtered optical signal into a microwave radar transmission signal and transmit it to the transceiver unit for transmission.

10. The system according to claim 8, characterized in that, The second photoelectric conversion unit includes: Second optical filter, second photodetector, second bandpass filter; The second optical filter is used to receive the optical signal generated by the second photoelectric modulator, filter the optical signal and then transmit it to the second photodetector. The second photodetector is used to convert the filtered optical signal into an intermediate frequency echo signal and transmit it to the second bandpass filter. The second bandpass filter is used to filter the intermediate frequency echo signal and transmit it to the feature generation module.

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