WO2022257530A1 - 激光雷达的控制方法及激光雷达 - Google Patents
激光雷达的控制方法及激光雷达 Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/483—Details of pulse systems
- G01S7/484—Transmitters
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/06—Systems determining position data of a target
- G01S17/08—Systems determining position data of a target for measuring distance only
- G01S17/10—Systems determining position data of a target for measuring distance only using transmission of interrupted, pulse-modulated waves
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/87—Combinations of systems using electromagnetic waves other than radio waves
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/88—Lidar systems specially adapted for specific applications
- G01S17/93—Lidar systems specially adapted for specific applications for anti-collision purposes
- G01S17/931—Lidar systems specially adapted for specific applications for anti-collision purposes of land vehicles
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/481—Constructional features, e.g. arrangements of optical elements
- G01S7/4814—Constructional features, e.g. arrangements of optical elements of transmitters alone
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/483—Details of pulse systems
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K7/00—Modulating pulses with a continuously-variable modulating signal
- H03K7/08—Duration or width modulation ; Duty cycle modulation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/483—Details of pulse systems
- G01S7/486—Receivers
- G01S7/4868—Controlling received signal intensity or exposure of sensor
Definitions
- the present invention generally relates to the technical field of laser detection, and in particular to a control method of a laser radar and the laser radar.
- Lidar is usually used for ranging based on the direct time-of-flight method (TOF), that is, by emitting laser pulses with narrow width but high peak power, and measuring the flight time of the laser pulse back and forth between the laser radar and the target for ranging.
- TOF direct time-of-flight method
- the measurement principle is based on the measurement of the time-of-flight of the emitted laser pulses. If each laser radar cannot determine whether the received echo pulse is sent by itself, then there is a certain probability that when receiving the echo pulse sent by other radars, it will also It is judged as an echo signal, which leads to an error in the ranging result, that is, crosstalk occurs.
- the problem of mutual interference between different laser radars has become one of the bottlenecks restricting its development.
- lasers are divided into four categories: Category 1: Laser radiation must not exceed the threshold of category 1 at the corresponding wavelength and emission duration Laser products; Class 1M: within the wavelength range of 0.3-4 ⁇ m, the energy threshold shall not exceed Class 1 and a smaller measurement aperture shall be adopted; Class 2: laser products whose laser radiation shall not exceed the Class 2 threshold at the corresponding wavelength and emission duration ; Class 2M: In the wavelength range of 0.7-1.4 ⁇ m, the energy threshold shall not exceed Class 2 and shall be evaluated with a smaller measurement aperture or a place farther away from the performance light; Class 3R and 3B: In any wavelength range, it is allowed to exceed Class 1 and Class 2 energy thresholds, but laser products that must not exceed the respective energy thresholds of 3R and 3B; Class 4: Personnel contact with laser products that may exceed the accessible emission limit of Class 3B.
- Category 1 Laser radiation must not exceed the threshold of category 1 at the corresponding wavelength and emission duration Laser products
- Class 1M within the wavelength range of 0.3-4 ⁇ m, the energy threshold shall not exceed Class 1 and
- the wavelength of the laser is set between 0.7-1.4 ⁇ m.
- the maximum safety for naked eyes is 3R.
- MPE average MPE max /N
- the calculated radiation dose MPEAVERAGE of a single pulse is 0.033J/m2. If a continuous pulse is used, the continuous pulse MPETRAIN is 1.962 ⁇ J/m2.
- the laser wavelength affects the maximum allowable radiation dose of a single pulse; under the same radiation time, when the emitted pulse frequency increases, the maximum allowable radiation dose of continuous pulses increases with The reduction; in the case of the same laser repetition frequency, when the irradiation time increases, the maximum allowable exposure of continuous pulses also decreases; the energy of a single pulse is lower than that of repeated pulses. That is, the maximum allowable irradiation energy of the laser is jointly determined by the wavelength, repetition frequency, irradiation angle and irradiation time.
- the present invention provides a control method for laser radar, including:
- S101 Transmit a laser pulse signal according to the pulse code and the current energy allocation strategy, the laser pulse signal includes multiple laser pulses using the pulse code to detect the target;
- S102 Receive echo information of the plurality of laser pulses reflected by the target.
- the sum of the energies of the multiple laser pulses is less than a first energy threshold, and the first energy threshold is determined according to the requirement that the total energy of the emitted pulses within a preset time is less than the human eye safety threshold.
- step S103 further includes:
- the distance measurement condition is judged according to the echo information of the target object, and when the distance measurement condition is the distance measurement condition, the energy of the distance measurement pulse is increased.
- step S103 further includes:
- the energy of the distance measurement pulse is increased, the energy of the proximity measurement pulse is decreased, and the energy of the proximity measurement pulse is greater than a second energy threshold.
- the telemetry condition includes that the target is located outside the first distance range
- the second energy threshold is determined according to the detection requirements of the second distance range
- the second distance range is less than or equal to the The first distance range
- the energy of the distance measurement pulse is gradually increased at each detection until the sum of the energy of the multiple laser pulses is close to the first An energy threshold.
- the energy of the distance measurement pulse is increased during the next detection, so that the sum of the energy of the multiple laser pulses is close to the first energy threshold , and the energy of the proximity pulse is close to the second energy threshold.
- step S103 further includes:
- the distance measurement pulse and the proximity measurement pulse with energy close to each other are transmitted in the next detection, and the energy of the multiple laser pulses is equal to and approach the first energy threshold.
- control method further includes:
- Adjusting the intensity peaks or pulse widths of the multiple laser pulses by adjusting the energy distribution of the multiple laser pulses when the laser radar is emitted next time.
- control method further includes:
- the pulse peak value of the multiple laser pulses is increased.
- control method further includes:
- the pulse width of the multiple laser pulses is extended/shortened by extending/shortening the emission time of the multiple laser pulses.
- control method further includes:
- the present invention also provides a laser radar, including:
- the emitting unit emits a laser pulse signal according to the pulse code and the current energy allocation strategy, and the laser pulse signal includes a plurality of laser pulses using the pulse code to detect the target;
- a receiving unit configured to receive echo information reflected by the plurality of laser pulses by the target
- the control unit is configured to update the energy allocation strategy adopted when the lidar is launched next time according to the echo information of the target.
- the sum of the energies of the multiple laser pulses is less than a first energy threshold, and the first energy threshold is determined according to the requirement that the total energy of the emitted pulses within a preset time is less than the human eye safety threshold.
- control unit is further configured to:
- the distance measurement condition is judged according to the echo information of the target object, and when the distance measurement condition is the distance measurement condition, the energy of the distance measurement pulse is increased.
- control unit is further configured to:
- the energy of the distance measurement pulse is increased, the energy of the proximity measurement pulse is decreased, and the energy of the proximity measurement pulse is greater than a second energy threshold.
- the telemetry condition includes that the target is located outside the first distance range
- the second energy threshold is determined according to the detection requirements of the second distance range
- the second distance range is less than or equal to the The first distance range
- the lidar further includes:
- the first energy adjustment unit is coupled with the at least one laser and the control unit, and is configured to adjust the driving current/voltage of the at least one laser under the control of the control unit, so as to adjust the laser The pulse peak value of the plurality of laser pulses at the next transmission of the radar.
- the lidar further includes:
- the second energy adjustment unit is coupled with the at least one laser and the control unit, and is configured to adjust the emission time of the at least one laser under the control of the control unit, so as to adjust the laser radar The pulse width of the plurality of laser pulses in one shot.
- a preferred embodiment of the present invention provides a laser radar control method, which emits multiple laser pulses coded at time intervals, and adjusts the energy distribution of the multiple laser pulses in the next emission according to the echo information of the target.
- the preferred embodiment of the present invention not only takes into account the anti-crosstalk requirements in the short-distance range, but also improves the detection accuracy and detection performance in the long-distance range, and obtains the maximum benefit of laser pulse energy while meeting the safety requirements of human eyes. application.
- Fig. 1 shows the control method of the lidar according to a preferred embodiment of the present invention
- Fig. 2 schematically shows the curve of laser eye safety power changing with time
- Fig. 3 schematically shows the emission pulse sequence and the echo pulse sequence of the lidar
- Fig. 4 schematically shows the transmitting pulse sequence of the laser radar and the echo pulse sequence received by other radars
- Figure 5A schematically illustrates the transmission of at least one proximity pulse and at least one telemetry pulse according to a preferred embodiment of the present invention
- Figure 5B schematically illustrates the transmission of at least one proximity pulse and at least one telemetry pulse according to a preferred embodiment of the present invention
- Fig. 6 schematically shows the echo situation of at least one proximity pulse and at least one telemetry pulse in different distance ranges according to a preferred embodiment of the present invention
- Fig. 7A schematically shows transmitting at least one proximity pulse and at least one distance measurement pulse with the same or similar pulse width and different peak powers according to a preferred embodiment of the present invention
- Fig. 7B schematically shows transmitting at least one proximity pulse and at least one telemetry pulse with the same or similar peak power and different pulse widths according to a preferred embodiment of the present invention
- Fig. 8 schematically shows a driving circuit of a laser according to a preferred embodiment of the present invention
- Fig. 9A schematically shows a driving circuit of a laser according to another preferred embodiment of the present invention.
- FIG. 9B shows the timing changes of each node of the driving circuit in FIG. 9A
- Fig. 10 schematically shows an energy regulation circuit according to a preferred embodiment of the present invention
- Fig. 11 schematically shows a laser pulse signal triggered by a switch control signal according to a preferred embodiment of the present invention
- Fig. 12A schematically shows a double pulse under encoding triggered by a switch control signal according to a preferred embodiment of the present invention
- Fig. 12B schematically shows a double pulse under another encoding triggered by a switch control signal according to a preferred embodiment of the present invention
- Fig. 13 schematically shows a lidar according to a preferred embodiment of the present invention.
- first and second are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features.
- a feature defined as “first” or “second” may explicitly or implicitly include one or more of said features.
- “plurality” means two or more, unless otherwise specifically defined.
- connection should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection.
- Connected, or integrally connected it can be mechanically connected, or electrically connected, or can communicate with each other; it can be directly connected, or indirectly connected through an intermediary, and it can be the internal communication of two components or the interaction of two components relation.
- a first feature being “on” or “under” a second feature may include that the first and second features are in direct contact, or may include the first and second features Not in direct contact but through another characteristic contact between them.
- “on”, “above” and “above” the first feature on the second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the level of the first feature is higher than that of the second feature.
- "Below”, “below” and “under” the first feature to the second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the first feature has a lower horizontal height than the second feature.
- the basic idea of the pulse coding scheme is: the laser radar emits laser pulses containing preset code information to detect the target; when receiving the echo, it is identified by the preset code to determine the reflected echo of the detection beam sent by the radar.
- the pulse encoding can adopt one or more of encoding methods such as time interval encoding, peak intensity encoding, and pulse width encoding.
- time interval coding multiple laser pulses containing time code information are emitted, preferably, double laser pulses with a preset time interval are emitted, and at the receiving end, according to the time interval of the pulse echo, it is judged whether the echo is the original The reflected echo of the detection beam emitted by the radar.
- the two laser pulses with a preset time interval may contain the same or different pulse energies, that is, two laser pulses with different energies can be emitted.
- multiple laser pulses containing peak intensity encoding information are emitted, preferably, three laser pulses with peak intensity having a "high-short-high" variation trend are emitted, and at the receiving end according to the pulse echo
- the ratio of the peak intensity (the peak intensity of the pulse echo will be attenuated compared with the transmitted pulse, but the ratio is basically unchanged, and a certain tolerance can be set), to determine whether the pulse echo is the reflection of the detection beam emitted by the radar echo.
- pulse width coding is used to transmit multiple laser pulses containing pulse width coding information.
- three laser pulses with pulse widths with a "wide-narrow-wide" variation trend are emitted, and at the receiving end according to the pulse echo Pulse width ratio (the echo pulse width will be wider than the transmitted pulse, but the ratio is basically unchanged, and a certain tolerance can be set), to judge whether the pulse echo is the reflected echo of the detection beam sent by the radar.
- the pulse energy available in one detection needs to be allocated to multiple laser pulses, and the amplitude/pulse width of multiple laser pulses will be affected.
- the energy obtained by each pulse under the scheme of pulse coding is lower, which reduces the distance measurement performance of the lidar.
- the preferred embodiment of the present invention provides a laser radar control method, within the scope of meeting the requirements of human eye safety, increase the energy of the distance measurement pulse as much as possible, compress the bottom line of the proximity measurement pulse as much as possible, and make the coded information Laser pulses can have better performance in distance measurement, and at the same time can achieve the effect of anti-crosstalk in near-field measurement.
- the present invention provides a laser radar control method 10, including step S101, step S102 and step S103.
- a laser pulse signal is emitted according to the pulse code and the current energy distribution strategy, and the laser pulse signal includes a plurality of laser pulses using the pulse code to detect the target.
- the pulse coding can adopt one or more of the above-mentioned time interval coding, peak intensity coding, and pulse width coding.
- the premise of the energy distribution strategy is that the sum of the energy of the transmitted pulses is less than the human eye safety threshold.
- Fig. 2 schematically shows the graph of the laser power changing with time for human eye safety (may be different because of different wavelengths, repetition frequencies, irradiation angles and irradiation times, both for different types of laser radars, There may be differences in this change curve), since the sum of the time of the transmitted pulses in one detection is much less than 5 ⁇ s, so it only needs to be considered that the energy sum of the transmitted pulses in one detection is less than the human eye safety energy threshold within 5 ⁇ s (for the curve shown in Figure 2 Integrate the eye-safe laser power).
- Fig. 2 schematically shows the graph of the laser power changing with time for human eye safety (may be different because of different wavelengths, repetition frequencies, irradiation angles and irradiation times, both for different types of laser radars, There may be differences in this change curve), since the sum of the time of the transmitted pulses in one detection is much less than 5 ⁇ s, so it only needs to be considered that the energy sum of the transmitted pulses in one detection is less than the human eye safety
- FIG. 2 is only a schematic form of the human eye safety power curve corresponding to a laser radar, and the actual human eye safety power conversion may be based on the measurement standards of different dimensions and/or the type and structure of the laser radar , performance and other aspects of the different resulting in different curves.
- step S102 echo information of the multiple laser pulses reflected by the target is received.
- the validity of the echo pulse is judged according to whether the echo pulse carries the same encoded information as the transmitted pulse.
- the echo pulse sequence when the timing of the echo pulse sequence is the same as that of the transmitting pulse sequence, the echo pulse sequence is judged as the echo signal of the transmitting pulse sequence, and the signal is retained. And extract the information carried by the signal.
- the echo pulse sequence when the timing of the echo pulse sequence is different from the timing of the transmit pulse sequence, the echo pulse sequence is judged to be the echo of the transmit pulse sequence emitted by other laser radars. echo signal and discard the echo pulse train.
- step S103 according to the echo information of the target, the energy allocation strategy adopted for the next launch of the laser radar is updated.
- the echo information of the target object judge the distance of the target object and the effectiveness of the echo pulse, and adjust the energy distribution strategy according to the distance of the target object and/or the effectiveness of the echo pulse, so as to meet the requirements of human eye safety. Achieve the best distance measurement performance, and at the same time ensure the anti-interference performance within a certain distance range.
- each detection pulse is usually kept relatively consistent in ranging capability, that is, multiple laser pulses with similar emission energies are used. Therefore, the small pulses (detection pulses with low energy or power) are often the bottleneck of LiDAR distance measurement performance.
- the needs of lidar distance measurement and proximity measurement are different.
- the distance measurement it is necessary to consider the distance measurement capability, and hope to achieve the detection distance as far as possible, which requires the laser pulse to have high energy; at the same time, the probability of crosstalk may be low during the distance measurement.
- the performance of large pulses detection pulses with high energy or power
- the probability of crosstalk at short distances increases. Therefore, in practice, it is only necessary to provide anti-crosstalk coding at short distances.
- the echo information of the target determine the distance range of the current target, or the current ranging conditions of the laser radar, and then according to the target Adjust the energy distribution of the laser pulse according to the distance range/ranging conditions of the object.
- the sum of the energies of the emitted multiple laser pulses is less than the first energy threshold, wherein the first energy threshold is based on the sum of the energies of the emitted pulses within the preset time
- the requirement to be less than the eye-safe threshold is determined.
- the total energy of the laser pulses emitted by the laser radar for multiple detections within a predetermined period of time needs to be less than the human eye safety threshold.
- the predetermined time period and the corresponding human eye safety threshold are different according to different detection methods and performances of the lidar.
- the total energy that can be used by the laser radar that adopts the mechanical rotation scanning detection method can be higher, because it will perform rotation scanning during the detection process and will not be fixed in one direction; LiDAR in the detection mode allows less energy because it points in a fixed direction, etc.
- the predetermined time period is a time interval on the order of microseconds, for example, about 5 ⁇ s.
- the time required for a lidar detection is tens of nanoseconds to hundreds of nanoseconds. That is, the time for one detection by the lidar is less than a predetermined time period.
- the sum of the pulse energy available for each detection can be determined, that is, the sum of the energy of multiple laser pulses emitted by a detection can be determined. For example, since the total time of the transmitted pulses in one detection is much less than 5 ⁇ s, it can be directly considered that the total energy of the transmitted pulses in one detection is less than the human eye safety threshold within 5 ⁇ s.
- the emitted multiple laser pulses include at least one telemetry pulse and at least one proximity pulse, and the at least one telemetry pulse and at least one
- the sequence of transmitting the proximity pulses is not limited, but the energy/power of the proximity pulses should not be greater than the energy/power of the long-range pulses.
- the pulse with the greatest energy can be used as the distance-measuring pulse, and the remaining at least two pulses can be used as the proximity pulse, so that the ranging Maximize capacity.
- a proximity pulse and a telemetry pulse coded at time intervals are transmitted, wherein the sequence of the proximity pulse and the telemetry pulse is not limited.
- peak intensity and pulse width can also be used for encoding, or a combination of multiple encoding methods in time interval, peak intensity, and pulse width can be used for encoding, all of which are within the protection scope of the present invention .
- Step S103 of the control method 10 further includes: judging the distance measurement condition according to the echo information of the target object, and increasing the energy of the distance measurement pulse when the distance measurement condition is the distance measurement condition.
- the radar is currently in the distance measurement condition:
- the target object is located outside the first distance range. For example, at a distance of 80 meters, the requirements for the performance of the lidar distance measurement are increased at this time, and the requirements for combating crosstalk are reduced.
- the first distance can be adjusted according to the actual situation and needs.
- the first distance range is used to indicate an area where better ranging performance can be obtained only based on the telemetry pulse;
- the echo of the received proximity pulse is weak or no echo of the proximity pulse is received. There may be many reasons at this time, for example, the target is located outside the first distance range, the energy of the proximity pulse is not enough to detect the target, all attenuation or almost all attenuation; the reflectivity of the target is low, and so on.
- the echoes of both the proximity pulse and the distance pulse can be received by the laser radar; when the target is within a distance of more than 80 meters, LiDAR can only pick up the echoes of the telemetry pulses.
- the energy of the distance measurement pulse is increased, the energy of the proximity pulse is decreased, and the energy of the proximity pulse is greater than the second energy threshold.
- the second energy threshold is determined by the basic requirements of the lidar for anti-jamming performance.
- the sum of the energy of multiple laser pulses must be less than the first energy threshold in one detection as mentioned above, in order to further increase the energy of the distance measuring pulse, it can be achieved by reducing the energy of the proximity measuring pulse.
- the first distance range for example, 80 meters
- the requirement for distance measurement performance is increased, and the requirement for anti-crosstalk function is reduced, and the energy of the proximity measurement pulse can be appropriately reduced.
- the echo of the proximity pulse is weak, or the echo of the proximity pulse is not received, the proximity pulse cannot play a practical role in analyzing the distance of the target object, so the proximity pulse can also be appropriately reduced energy of.
- the limitation on the proximity pulse energy is determined by the basic anti-crosstalk requirements of the laser radar, that is, when the target returns to within the second distance range (for example, 50 meters), the demand for the anti-crosstalk function of the laser radar increases. The requirements are lowered. In this case, the laser radar is required to still be able to detect and distinguish the reflected echoes of the detection beam emitted by the radar.
- the telemetry condition includes that the target is located outside the first distance range (for example, 80 meters), and the second energy threshold is determined according to the detection requirements of the second distance range (for example, 50 meters).
- the first distance range is 80 meters and the second distance range is 50 meters. According to actual detection needs, it is also feasible to set the first distance range to be less than or equal to the first distance range. Yes, these are all within the protection scope of the present invention.
- the second distance range is the range where the laser radar has a high anti-crosstalk requirement. For example, within the range of 50 meters near the laser radar, the laser radar The emitted echo signal corresponding to the detection beam may be affected by other lidars mounted on the vehicle, or by the lidars mounted on nearby passing vehicles.
- the first distance range is the range where the laser radar has high requirements for distance measurement performance. For example, within the range of 80 meters away from the laser radar, the distance measurement condition includes analyzing the target object located outside the first distance range according to the echo information. .
- the energy of the distance measurement pulse is gradually increased at each detection until the sum of the energy of multiple laser pulses is close to the first energy threshold, wherein the energy of the proximity pulse is not lower than the second energy threshold.
- the first energy threshold is determined according to the human eye safety threshold
- the second energy threshold is determined according to the basic requirements of the lidar for anti-jamming performance. That is, the energy allocation strategy is switched step by step.
- the first energy threshold determined according to the human eye safety threshold is 800nJ
- the second energy threshold determined according to the basic anti-jamming requirements of the lidar is 100nJ.
- the energy distribution strategy of the dual-pulse detection scheme using time interval coding is shown in the table below.
- pulse code Telemetry pulse energy Measuring near pulse energy PCode1 300nJ 300nJ PCode2 400nJ 300nJ PCode3 500nJ 300nJ PCode4 600nJ 200nJ PCode5 700nJ 100nJ
- the default is to use PCode1 for encoding.
- the energy of the distance measurement pulse is increased by 100nJ, that is, it is switched to PCode2; the distance measurement condition is still determined according to the echo information.
- the remote condition in the next detection, increase the energy of the long-distance pulse by 100nJ, that is, switch to PCode3.
- the upper limit of the sum of the double-pulse energy can be set near the first energy threshold and not exceeding the first energy threshold, such as 750nJ); according to the echo information, when the distance measurement condition is still the distance measurement condition, in the next detection, the Increase the energy of the telemetry pulse by 100nJ, and reduce the energy of the proximity pulse by 100nJ at the same time, that is, switch to PCode4; judge that the distance measurement condition is still the telemetry condition according to the echo information, and increase the energy of the distance measurement pulse by 100nJ in the next detection At the same time, reduce the energy of the proximity pulse by 100nJ, that is, switch to PCode5.
- the energy of the proximity pulse has dropped to the second energy threshold; if the distance measurement condition is still the distance measurement condition according to the echo information, the next time For detection, continue to use PCode5 for detection; if in any detection, if the distance measurement condition is judged to be the proximity condition according to the echo information (that is, there may be a target at a short distance), the code can be switched back to PCode1...
- the measurement Remote conditions include:
- the ranging information obtained within the predetermined time is all located outside the first distance range (for example, 80 meters). Analyzing the distance of the target object according to the echo information, the ranging information obtained within a predetermined time indicates that the target object is located outside the first distance range; and/or
- the echo of the received proximity pulse is weak or no echo of the proximity pulse is received;
- the radar optical axis faces a specific angle (for example, facing the front of the vehicle).
- the demand for detection accuracy is increased, and for the front direction, the crosstalk of surrounding vehicles is improved, and the demand for anti-interference is relatively reduced.
- the energy distribution measurement is adjusted between the proximity pulse and the distance measurement pulse, so as to Optimize probing results.
- the step size of the step-by-step adjustment can be made larger or smaller. It can even achieve the effect of approximately stepless adjustment, for example, by setting a resistance adjustment module that can be approximately steplessly changed, the stepless adjustment of laser energy can be realized.
- the energy of the distance measurement pulse is increased during the next detection, so that the energy sum of multiple laser pulses is close to the first energy threshold, and the energy of the proximity pulse The energy approaches a second energy threshold.
- the "closer” mentioned here is used to indicate the trend of energy adjustment, that is: the sum of the adjusted energies of the multiple laser pulses is closer to the first energy threshold than the sum of the energies before the adjustment, and, The energy of the proximity pulse after adjustment is closer to the second energy threshold than the energy before adjustment.
- the first energy threshold is determined according to the human eye safety threshold, for example, according to the laser product safety standards of various countries or regions and the type and detection mode of the actual radar product used, the first energy threshold can be calculated; the second energy threshold is based on the laser
- the basic requirements of radar for anti-jamming performance are determined. That is, a one-time switch is performed for the energy allocation strategy.
- the first energy threshold determined according to the human eye safety threshold is 800nJ
- the second energy threshold determined according to the basic anti-jamming requirements of the lidar is 100nJ.
- the energy allocation strategy of the dual-pulse detection scheme using time interval coding is shown in the table below.
- pulse code Measuring near pulse energy Telemetry pulse energy PCode6 400nJ 400nJ PCode7 600nJ 200nJ
- Telemetry conditions include:
- the ranging information obtained within the predetermined time is all located outside the first distance range (for example, 80 meters); and/or
- the echo of the received proximity pulse is weak or no echo of the proximity pulse is received;
- the radar optical axis faces a specific angle (for example, facing the front of the vehicle).
- the multiple laser pulses include at least one telemetry pulse and at least one proximity pulse
- step S103 further includes:
- the proximity conditions include:
- the ranging information obtained within the predetermined time is all within the second distance range (for example, 50 meters). That is, the distance of the target object is analyzed according to the echo information, and the ranging information obtained within a predetermined time indicates that the target object is located in an area where crosstalk frequently occurs near the laser radar; and/or
- the distance measurement pulse and the proximity measurement pulse with energy close to each other are transmitted at the next detection, and the energy sum of multiple laser pulses is close to the first energy threshold . Transmits a double pulse sequence coded at time intervals with similar energies to achieve the best short-distance detection performance (anti-crosstalk performance).
- the first energy threshold determined according to the human eye safety threshold is 800nJ
- the second energy threshold determined according to the basic anti-jamming requirements of the lidar is 100nJ.
- the dual-pulse detection scheme using time interval coding, the energy distribution strategy is shown in Table 2 above: currently PCode2 is used for coding, and when the proximity conditions are met, switch to PCode1.
- control method 10 further includes:
- Adjust the intensity peak or pulse width of multiple laser pulses by adjusting the energy distribution of multiple laser pulses when the lidar is next fired.
- the peak intensity and/or pulse width of the laser pulse can be adjusted to achieve the purpose of adjusting energy distribution.
- the ratio (change trend) of the peak intensity can be kept unchanged, and the energy distribution can be adjusted by adjusting the pulse width.
- the ratio (change trend) of the pulse width can be kept unchanged, and the energy distribution can be adjusted by adjusting the peak intensity.
- the proximity pulse and the distance pulse in the same detection can have the same or similar pulse time, but different peak powers (as shown in FIG. 7A ), It is also possible that the pulse peak power is the same or similar, but the pulse time is different (as shown in FIG. 7B ).
- the pulse peak power is the same or similar, but the pulse time is different (as shown in FIG. 7B ).
- FIG. 7A preferably, it is applied to a multi-channel mechanical radar, and the detection accuracy is improved through a telemetry pulse with a high peak power, and crosstalk is prevented through a double pulse code.
- FIG. 7B preferably, it is applied to an area array flash solid-state lidar, and the telemetry pulse with a wider pulse width is used to increase the probability of photon reception, and the double-pulse code is used to prevent crosstalk.
- the operations required to adjust the peak intensity and/or pulse width are also different.
- the detection end does not need to be adjusted accordingly when energy adjustment is performed; for example, when peak encoding is used, the initial waveform
- the pulse width of each pulse is the same and the peak value is different
- the distribution ratio information used by the detection terminal for verification can be based on The adjustment of energy distribution is updated; similarly, when pulse width encoding is used, the pulse width of each pulse in the initial waveform is different, and the peak value is the same, then when the energy distribution is adjusted, the distribution ratio adopted by the detection end can also be updated accordingly information.
- the transmitting unit of the laser radar emits a multi-pulse sequence using time interval coding and an energy distribution strategy.
- this multi-pulse sequence for example, the first laser pulse and the second laser pulse (a telemetry pulse) are included. and a proximity pulse), of course, is not general, and may also include the first laser pulse, the second laser pulse...the Nth laser pulse, and the multiple laser pulses have a time sequence relationship.
- the above time interval describes the timing relationship of the transmitted pulse sequence.
- the receiving unit can still determine the reflected echo of the transmitted pulse sequence sent by the radar by verifying the timing relationship between the echo pulse sequence and the transmitted pulse sequence.
- the transmitting unit of the laser radar transmits a multi-pulse sequence using peak intensity encoding and an energy distribution strategy, wherein the energy distribution strategy includes: reducing the energy of the proximity pulse in the case of conforming to the distance measurement mode , and increase the energy of the telemetry pulse.
- the multi-pulse sequence includes a distance-measuring pulse and a proximity-measuring pulse.
- the peak ratio of the distance-measuring pulse and the proximity-measuring pulse is 1.2:1. :1, to determine whether the pulse received is the laser radar to which it belongs.
- the energy of the proximity pulse is reduced by 50%, and the 50% energy is transferred to the distance measurement pulse.
- the distance between the distance measurement pulse and the proximity pulse The peak ratio may be 1.7:0.5, that is, 3.4:1, and correspondingly update the peak ratio of the echo pulse judged by the detection end to be 3.4:1.
- the transmitting end transmits the distance measuring pulse and the proximity measuring pulse according to the new energy distribution ratio measurement, and the detecting end judges whether the received echo is a correct echo pulse according to the new energy distribution ratio.
- the transmitting unit of the laser radar transmits a multi-pulse sequence using a pulse width encoding and energy allocation strategy.
- the multi-pulse sequence includes a strong pulse and a weak pulse, and the pulse width ratio of the strong pulse to the weak pulse is 2:1, that is, the pulse width of the strong pulse is twice that of the weak pulse.
- the detection end determines whether the received pulse is the laser radar to which it belongs.
- the transmitting end transmits the distance measuring pulse and the proximity measuring pulse according to the new energy distribution ratio measurement, and the detecting end judges whether the received echo is the correct echo pulse according to the new energy distribution ratio.
- the lidar continues to detect according to the new energy distribution ratio.
- the current distance measurement information is 46 meters and belongs to the proximity mode
- the ratio is 1.5:1, so that the pulse codes of the long-range pulse and the near-measuring pulse can be better used to distinguish the pulses emitted by the laser radar.
- the distance measurement mode can have multiple levels.
- the distance measurement mode can be divided into medium and long distance (for example, 50-100 meters) and ultra long distance (for example, greater than 100 meters), and the detection end is only in In the mid-range and long-range mode, the judgment is performed according to the new energy distribution ratio.
- the ultra-long-range mode as long as the echo pulse is received, it is regarded as the echo pulse corresponding to the telemetry pulse.
- the interference from other lidars or emission sources is already very small and can be ignored, and only the pulses that can be received can be considered. At this point, the detection end can no longer verify the pulse code.
- part of the proximity pulse when a detection is encoded with one distance measurement pulse and more than two proximity pulses, part of the proximity pulse can be removed, and the energy of this part of the proximity pulse can be allocated to the distance measurement pulse Pulse, and correspondingly adjust the anti-crosstalk judgment conditions adopted by the detection end to make judgments based on the pulse code after the energy is redistributed.
- the lidar initially uses three-pulse encoding, and the peak ratio of the three pulses pulse1, pulse2, and pulse3 is 1:2:3, of which the largest peak value is the long-range pulse, and the remaining two are near-measuring pulses.
- the detection end needs to determine that the echo pulse belongs to the laser radar when it receives three echo pulses and the energy ratio of the three echo pulses is 1:2:3.
- the laser radar determines that it is currently in the distance measurement mode, the energy of the pulse pulse1 with the smallest energy is transferred to the largest pulse pulse3, that is, the laser radar only transmits double-pulse codes with a peak ratio of 2:4, and updates the detection end.
- the judgment condition is to determine that the echo pulse belongs to the laser radar when receiving two pulses with an energy ratio of 2:4. Conversely, when entering the proximity mode from the distance measurement mode, the transmission and detection are still performed according to the three-pulse encoding with a peak ratio of 1:2:3.
- a certain tolerance can be set for the energy distribution of the telemetry pulse and the proximity pulse.
- the transmitting unit adjusts the energy distribution strategy by adjusting the pulse width of multiple laser pulses
- the receiving unit determines the pulse of the multi-pulse sequence for this detection according to the energy distribution strategy updated by the control unit of the laser radar The preset proportional relationship of the width, and then by verifying the ratio of the echo pulse sequence to the pulse width of the transmitted pulse sequence to determine the reflected echo of the transmitted pulse sequence sent by the radar, a certain tolerance can be set.
- the energy distribution measurement in the case of distance measurement can only increase the distance energy of the pulse without reducing the energy of the near-measuring pulse.
- control method 10 further includes: increasing the pulse peak value of the multiple laser pulses by increasing the maximum driving current/voltage of the multiple laser pulses.
- a voltage-adjustable driving circuit or a laser driving circuit including multiple energy storage circuits can be used to adjust the energy of each pulse.
- the current on the laser is directly proportional to the driving voltage applied to the laser, and inversely proportional to the resistance of the circuit where the laser is located. Therefore, there are two main ways to adjust the current/voltage on the laser, one is to adjust the driving voltage, and the other is to adjust the resistance.
- FIG. 8 shows a schematic diagram of an implementation of a circuit structure that can adjust the energy of the emission pulse by adjusting the current on the laser.
- the current of the laser shown in Figure 8 has the following relationship with the applied voltage and resistance:
- HVDD1 is the driving voltage applied on the laser
- Rd is the equivalent resistance of the laser itself
- Rdson is the total resistance of the PMOS and other devices connected to it. Therefore, there are two main methods for adjusting Imax, one is to adjust the voltage HVDD1, and the other is to adjust the resistance Rdson.
- a control module On the basis of the above adjustable circuit, a control module is integrated.
- the control module can switch multiple sets of pulse codes, which can be directly switched based on the above two coding methods, or pulse codes adjusted step by step to generate pulse control signals respectively.
- pulse control signal to adjust the input voltage HVDD1, or the resistance value Rdson to emit corresponding laser pulses.
- the timing diagram of the regulating circuit shown in FIG. 9A is shown in FIG. 9B.
- the current intensity of the laser corresponds to the magnitude of the voltage Vx
- Vx can be passed through the low voltage Linear regulator (LDO) output V2 to regulate.
- LDO Linear regulator
- Vx becomes smaller
- Vx becomes larger
- the laser current can be adjusted, that is, the emission pulse can be adjusted.
- Fig. 10 schematically shows a circuit implementation using an energy storage module.
- multiple energy storage modules are connected to the power supply module, each energy storage module is connected to a control switch, and the control switch is responsible for controlling the on-off of the energy storage module and the laser emitting unit.
- the control switch is responsible for controlling the on-off of the energy storage module and the laser emitting unit.
- the control switch between a certain energy storage module and the laser emitting unit is closed, the charge stored in the energy storage module drives the laser emitting unit to emit light pulses.
- the unit switches shown in FIG. 10 may be independent of each other, and the control switches are independently controlled by the control unit. At the same moment in time sequence, the control unit may control the control switches to open or close independently.
- the emitted laser pulse energy is the sum of the energy of several energy storage modules.
- the detection of distant objects can be realized.
- the pulse shape transmitted in the sequence can be controlled. For example, at a certain moment, only one control switch is closed, then the pulse intensity transmitted at this moment is 1 unit, and at a subsequent time N control switches are closed, then the pulse intensity transmitted at the corresponding moment is N units.
- the timing and intensity of the emission pulses can be controlled.
- multiple laser pulses with the same or similar pulse width and different peak powers are obtained by controlling the emission time of multiple laser pulses.
- the switch trigger signal (TRIGGER) is triggered at the end of the switch control signal (GATE1, GATE2,..., GATEN), for example, the timing falling edge of the switch control signal (GATE1, GATE2,..., GATEN) shown in the figure triggers the switch trigger signal (TRIGGER ) falling edge; without loss of generality, if the end of the switch trigger signal (TRIGGER) is the rising edge of the timing signal, the rising edge is used as the trigger timing of the switch control signal, so as to ensure that the light emitting process starts after the charging is completed, and After the previous charging and lighting process ends, the next charging-lighting process can start immediately.
- control method 10 further includes:
- the driving current/voltage is kept constant, and the pulse width of the multiple laser pulses is extended/shortened by extending/shortening the emission time of the multiple laser pulses. That is, multiple laser pulses with the same or similar peak power and different pulse widths are obtained as shown in FIG. 7B .
- the specific circuit implementation structure for adjusting the emission time will not be repeated here.
- the present invention also provides a laser radar 100 including a transmitting unit 110 , a receiving unit 120 and a control unit 130 . in:
- the emitting unit 110 emits a laser pulse signal, the laser pulse signal includes a plurality of laser pulses coded at time intervals, for detecting the target;
- the receiving unit 120 is configured to receive echo information of the multiple laser pulses reflected by the target;
- the control unit 130 is configured to adjust the energy distribution of the plurality of laser pulses when the laser radar emits next time according to the echo information of the target.
- the sum of the energies of multiple laser pulses is less than a first energy threshold, and the first energy threshold is determined according to the requirement that the total energy of the emitted pulses within a preset time is less than the human eye safety threshold.
- control unit 130 is further configured to:
- the distance measurement condition is judged according to the echo information of the target object, and when the distance measurement condition is the distance measurement condition, the energy of the distance measurement pulse is increased.
- control unit 130 is further configured to:
- the energy of the distance measurement pulse is increased, and the energy of the proximity pulse is decreased, and the energy of the proximity pulse is greater than the second energy threshold.
- the second energy threshold is determined according to the detection requirements of the second distance range, and the second distance range is less than or equal to the first distance range .
- the lidar 100 also includes:
- the first energy adjustment unit is coupled with the at least one laser and the control unit 130, and is configured to adjust the driving current/voltage of the at least one laser under the control of the control unit 130, so as to adjust the laser radar 100 when it emits the next time Pulse peak of multiple laser pulses.
- the lidar 100 also includes:
- the second energy adjustment unit is coupled with the at least one laser and the control unit 130, and is configured to adjust the emission time of the at least one laser under the control of the control unit 130, so as to adjust the laser radar 100 when it emits next time.
- the pulse width of the laser pulse is coupled with the at least one laser and the control unit 130, and is configured to adjust the emission time of the at least one laser under the control of the control unit 130, so as to adjust the laser radar 100 when it emits next time.
- the pulse width of the laser pulse is coupled with the at least one laser and the control unit 130, and is configured to adjust the emission time of the at least one laser under the control of the control unit 130, so as to adjust the laser radar 100 when it emits next time.
- a preferred embodiment of the present invention provides a laser radar control method, which emits multiple laser pulses coded at time intervals, and adjusts the energy distribution of the multiple laser pulses in the next emission according to the echo information of the target.
- the preferred embodiment of the present invention not only takes into account the anti-crosstalk requirements in the short-distance range, but also improves the detection accuracy and detection performance in the long-distance range, and obtains the maximum benefit of laser pulse energy while meeting the safety requirements of human eyes. application.
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Abstract
Description
脉冲编码 | 测远脉冲能量 | 测近脉冲能量 |
PCode1 | 300nJ | 300nJ |
PCode2 | 400nJ | 300nJ |
PCode3 | 500nJ | 300nJ |
PCode4 | 600nJ | 200nJ |
PCode5 | 700nJ | 100nJ |
脉冲编码 | 测近脉冲能量 | 测远脉冲能量 |
PCode6 | 400nJ | 400nJ |
PCode7 | 600nJ | 200nJ |
Claims (20)
- 一种激光雷达的控制方法,包括:S101:根据脉冲编码以及当前的能量分配策略,发射激光脉冲信号,所述激光脉冲信号包括采用所述脉冲编码的多个激光脉冲,用以探测目标物;S102:接收所述多个激光脉冲被目标物反射的回波信息;和S103:根据所述目标物的回波信息,更新所述激光雷达下一次发射时所采用的所述能量分配策略。
- 如权利要求1所述的控制方法,其中所述多个激光脉冲的能量之和小于第一能量阈值,所述第一能量阈值根据预设时间内发射脉冲的总能量小于人眼安全阈值的要求确定。
- 如权利要求2所述的控制方法,其中所述多个激光脉冲包括至少一个测远脉冲和至少一个测近脉冲,步骤S103进一步包括:根据所述目标物的回波信息判断测距条件,当测距条件为测远条件时,提高所述测远脉冲的能量。
- 如权利要求3所述的控制方法,其中步骤S103进一步包括:当所述测距条件为测远条件时,提高所述测远脉冲的能量,降低所述测近脉冲的能量,且所述测近脉冲的能量大于第二能量阈值。
- 如权利要求4所述的控制方法,其中所述测远条件包括所述目标物位于第一距离范围以外,所述第二能量阈值根据第二距离范围的探测需求确定,所述第二距离范围小于等于所述第一距离范围。
- 如权利要求3-5中任一项所述的控制方法,当所述测距条件为测远条件时,在每次探测时逐级提高所述测远脉冲的能量,直到所述多个激光脉冲的能量之和接近所述第一能量阈值。
- 如权利要求4或5所述的控制方法,当所述测距条件为测远条件时,在下一次探测时提高所述测远脉冲的能量,使得所述多个激光脉冲的能量之和接近所述第一能量阈值,且所述测近脉冲的能量接近所述第二能量阈值。
- 如权利要求2所述的控制方法,其中所述多个激光脉冲包括至少一个测远脉冲和至少一个测近脉冲,步骤S103进一步包括:根据所述目标物的回波信息判断测距条件,当测距条件为测近条件时,降低所述测远脉冲的能量,提高所述测近脉冲的能量,且在同一次发射中所述测近脉冲的能量小于等于所述测远脉冲的能量。
- 如权利要求8所述的控制方法,当所述测距条件为测近条件时,在下一次探测时发射能量接近的所述测远脉冲和所述测近脉冲,且使得所述多个激光脉冲的能量之和接近所述第一能量阈值。
- 如权利要求1-5、8、9中任一项所述的控制方法,进一步包括:通过调整所述激光雷达下一次发射时所述多个激光脉冲的能量分配,以调整所述多个激光脉冲的强度峰值或脉冲宽度。
- 根据权利要求10所述的控制方法,进一步包括:通过提高所述多个激光脉冲的最大驱动电流/电压,来提升所述多个激光脉冲的脉冲峰值。
- 根据权利要求10所述的控制方法,进一步包括:保持驱动电流/电压不变,通过延长/缩短所述多个激光脉冲的发射时间,来扩展/缩短所述多个激光脉冲的脉冲宽度。
- 如权利要求1-5、8、9中任一项所述的控制方法,进一步包括:根据所述多个激光脉冲对应的回波信息计算所述目标物的距离。
- 一种激光雷达,包括:发射单元,根据脉冲编码以及当前的能量分配策略,发射激光脉冲信号,所述激光脉冲信号包括采用所述脉冲编码的多个激光脉冲,用以探测目标物;接收单元,配置成接收所述多个激光脉冲被目标物反射的回波信息;控制单元,配置成根据所述目标物的回波信息,更新所述激光雷达下一次发射时所采用的所述能量分配策略。
- 如权利要求14所述的激光雷达,其中所述多个激光脉冲的能量之和小于第一能量阈值,所述第一能量阈值根据预设时间内发射脉冲的总能量小于人眼安全阈值的要求确定。
- 如权利要求15所述的激光雷达,其中所述多个激光脉冲包括至少一个测远脉冲和至少一个测近脉冲,所述控制单元进一步被配置成:根据所述目标物的回波信息判断测距条件,当测距条件为测远条件时,提高所述测远脉冲的能量。
- 如权利要求16所述的激光雷达,其中所述控制单元进一步被配置成:当所述测距条件为测远条件时,提高所述测远脉冲的能量,降低所述测近脉冲的能量,且所述测近脉冲的能量大于第二能量阈值。
- 如权利要求17所述的激光雷达,其中所述测远条件包括所述目标物位于第一距离范围以外,所述第二能量阈值根据第二距离范围的探测需求确定,所述第二距离范围小于等于所述第一距离范围。
- 如权利要求14-18中任一项所述的激光雷达,其中所述发射单元包括至少一个激光器,所述激光雷达还包括:第一能量调节单元,与所述至少一个激光器和所述控制单元耦接,并配置成可在 所述控制单元的控制下调节所述至少一个激光器的驱动电流/电压,用以调整所述激光雷达下一次发射时所述多个激光脉冲的脉冲峰值。
- 如权利要求14-18中任一项所述的激光雷达,其中所述发射单元包括至少一个激光器,所述激光雷达还包括:第二能量调节单元,与所述至少一个激光器和所述控制单元耦接,并配置成可在所述控制单元的控制下调节所述至少一个激光器的发射时间,用以调整所述激光雷达下一次发射时所述多个激光脉冲的脉冲宽度。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
MX2023014516A MX2023014516A (es) | 2021-06-07 | 2022-03-17 | Metodo de control para lidar y lidar. |
DE112022002066.0T DE112022002066T5 (de) | 2021-06-07 | 2022-03-17 | Steuerverfahren für ein lidar und lidar |
EP22819135.9A EP4354175A1 (en) | 2021-06-07 | 2022-03-17 | Control method for lidar, and lidar |
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CN116559896A (zh) * | 2023-07-10 | 2023-08-08 | 深圳市欢创科技有限公司 | 调整激光雷达测距精度的方法、装置及激光雷达 |
CN117471433A (zh) * | 2023-12-28 | 2024-01-30 | 广东威恒输变电工程有限公司 | 基于高反射强度标靶的施工机械激光点云实时提取方法 |
WO2024139685A1 (zh) * | 2022-12-28 | 2024-07-04 | 武汉万集光电技术有限公司 | Opa激光雷达、目标探测方法、装置、介质和产品 |
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MX2023014516A (es) | 2024-01-29 |
KR20230170761A (ko) | 2023-12-19 |
US20240175993A1 (en) | 2024-05-30 |
EP4354175A1 (en) | 2024-04-17 |
DE112022002066T5 (de) | 2024-01-25 |
JP2024521950A (ja) | 2024-06-04 |
CN115508850A (zh) | 2022-12-23 |
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