A lidar bottom noise measurement method, lidar, vehicle, electronic device and storage medium

Abstract

The application discloses a laser radar bottom noise measurement method, a laser radar, a vehicle, an electronic device and a storage medium. The method comprises the following steps: instructing the laser radar to detect bottom noise in a bottom noise measurement period by one or more processors, wherein the bottom noise measurement period is arranged in a ranging period of the laser radar, a plurality of ranging periods form a scanning area of the laser radar, and a scanner of the laser radar runs from a scanning starting point to a scanning ending point in the scanning area; instructing the laser radar to emit outgoing light in a light emission period after the bottom noise measurement period by the one or more processors; and instructing the laser radar to detect a return signal in a return detection period after the light emission period by the one or more processors.

Description

Technical Field

[0001] This disclosure relates to the field of laser detection, and more specifically, to a method for measuring the noise floor of a lidar, a lidar, a vehicle, electronic equipment, and a storage medium. Background Technology

[0002] LiDAR, also known as Laser Detection and Ranging (LiDAR or LADAR) systems, measures the position, velocity, and other information of a target object by emitting a laser beam towards it and receiving the beam reflected back from the target. In the light detected by the LiDAR's optical receiver, besides the expected reflected light from the target object, there is often stray light from other objects in the field of view (FOV), forming the LiDAR's noise floor. This noise includes ambient light such as strong sunlight, headlights from other vehicles, or beams from other LiDAR sources. A high noise floor significantly degrades the signal-to-noise ratio (SNR) of the optical receiver's output signal, reducing measurement accuracy and posing challenges to the use of LiDAR.

[0003] Therefore, it is necessary to measure the noise floor of the lidar in order to improve its detection performance. Summary of the Invention

[0004] This disclosure provides a method for measuring the noise floor of a lidar, a lidar, an electronic device, and a storage medium to solve the problem of inaccurate noise floor measurements in lidar.

[0005] According to one aspect of this disclosure, a method for measuring the noise floor of a lidar is provided, comprising:

[0006] One or more processors instruct the lidar to detect noise floor during the noise floor measurement period, wherein the noise floor measurement period is set within the ranging cycle of the lidar, and multiple ranging cycles constitute the scanning area of ​​the lidar, within which the lidar scanner runs from the scanning start point to the scanning end point;

[0007] The one or more processors instruct the lidar to emit outgoing light during the light emission period following the noise floor measurement period;

[0008] The one or more processors instruct the lidar to detect the echo signal during the echo detection period following the light emission period.

[0009] Optionally, the lidar is a non-coaxial lidar, which includes multiple receiving channels; the method further includes: instructing the lidar to perform receiving channel switching during a channel switching period prior to the noise floor measurement period by the one or more processors.

[0010] Optionally, according to the lidar noise floor measurement method according to claim 1, the ranging period is the measurement period of a single scanning point of the lidar; all ranging periods of the scanning area and the retrace area constitute one frame of the lidar.

[0011] Optionally, the duration of the channel switching period is such that the receiving channel switching is completed and the channel is in a stable state.

[0012] Optionally, the one or more processors instruct the lidar to determine the ranging start time during the light emission period.

[0013] Optionally, determining the ranging start time includes at least one of the following methods:

[0014] The one or more processors instruct the lidar to determine the ranging start time based on the time of receiving the dispersed emitted light;

[0015] The one or more processors instruct the lidar to determine the ranging start time based on the trigger signal of the emitted light;

[0016] The one or more processors instruct the lidar to determine the ranging start time based on a copy signal of the trigger signal for emitting laser light, wherein the copy signal is a preset time earlier than the trigger signal.

[0017] According to a second aspect of this disclosure, a lidar is provided, comprising:

[0018] The light source is configured to emit light;

[0019] A scanner is configured to direct the light to scan a target object;

[0020] A light receiver is configured to detect light reflected by the target object; and

[0021] A controller, communicatively coupled to the light source, the scanner, and the light receiver, is configured to perform the above-described noise floor measurement method.

[0022] Optionally, the light source includes a semiconductor laser or a fiber laser.

[0023] According to a third aspect of this disclosure, a vehicle is provided that includes the aforementioned lidar.

[0024] According to a fourth aspect of this disclosure, an electronic device is provided, comprising: a processor and a memory for storing processor-executable instructions, wherein the processor is configured to execute the above-described lidar noise floor measurement method when the executable instructions in the memory are invoked.

[0025] According to a fifth aspect of this disclosure, a non-transitory computer-readable storage medium is provided, which, when instructions in the storage medium are executed by a processor of an electronic device, enables the electronic device to perform the aforementioned lidar noise floor measurement method.

[0026] The technical effect that can be achieved by the present disclosure is that by setting the noise floor measurement period within the ranging cycle of the scanning area of ​​the lidar, the measured noise floor is closer to the actual noise floor during lidar detection. Using the noise floor measured by the present disclosure for ranging can improve the accuracy of ranging.

[0027] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the specific embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a flowchart of a lidar noise floor measurement method according to a first embodiment of the present disclosure.

[0030] Figure 2 This is a schematic diagram of the composition of a lidar according to an embodiment of the present disclosure.

[0031] Figure 3 This is a timing diagram for the light source control of a lidar according to one embodiment of the first embodiment of the present disclosure.

[0032] Figure 4 This is a signal timing diagram of the ranging cycle of a lidar according to a first embodiment of the present disclosure.

[0033] Figure 5 The diagram illustrates (a) a scheme for measuring distance with a lidar according to a first embodiment of the present disclosure and (b) a signal timing diagram for measuring objects at close range.

[0034] Figure 6 (a) A schematic diagram of a scheme for measuring distance using a replicated signal using a lidar according to an embodiment of the first embodiment of the present disclosure, and (b) a signal timing diagram of measuring a nearby object using a replicated signal.

[0035] Figure 7 This is a signal timing diagram of the ranging cycle of a lidar according to another embodiment of the first embodiment of the present disclosure.

[0036] Figure 8 This is a schematic diagram of the structure of a lidar according to a second embodiment of the present disclosure. Specific Implementation

[0037] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of systems consistent with some aspects of this disclosure as detailed in the appended claims.

[0038] See Figure 1 According to a first embodiment of this disclosure, a method for measuring the noise floor of a lidar is provided, the method comprising:

[0039] S1, one or more processors instruct the lidar to detect noise floor during the noise floor measurement period, wherein the noise floor measurement period is set within the lidar's ranging cycle, and multiple ranging cycles constitute the lidar's scanning area.

[0040] Within the scanning area, the LiDAR scanner moves from the starting point of the scan to the ending point;

[0041] S2, where one or more processors instruct the lidar to emit outgoing light during the light emission period following the noise floor measurement period;

[0042] S3, which is instructed by one or more processors, to detect the echo signal during the echo detection period following the light emission period.

[0043] This disclosure sets the noise floor measurement period within the ranging cycle of the lidar's scanning area, that is, the noise floor measurement period is set within the lidar's ranging cycle for noise floor measurement. Since the noise floor measurement time is close to the measurement time, the measured noise floor is closer to the actual noise floor during lidar detection. Using the noise floor measured by this disclosure for ranging can improve the accuracy of ranging.

[0044] Because the scheme of this disclosure sets a noise floor measurement period in the scanning area, the echo acquisition time is shortened compared to the prior art. Although it affects the maximum range value, for short-range (e.g., ranging range of 1m-50m) blind spot fill radar, the noise floor needs to be collected for a period of time in each ranging cycle. The loss of the maximum range is within an acceptable range for such radar. Therefore, the method of this disclosure can be applied to short-range blind spot fill lidar.

[0045] Figure 2An exemplary lidar 100 is shown, to which the techniques of this disclosure can be applied. Lidar 100 may include a light source 102, a scanner 104, a light receiver 106, and a controller 108. The light source 102 emits an emitted beam for scanning a target object 120. The light source 102 may be a laser, such as a solid-state laser (e.g., a vertical-cavity surface-emitting laser (VCSEL) or an external-cavity semiconductor laser (ECDL)), a laser diode, or a fiber laser. The light source 102 may also include an LED. The light source 102 may emit different forms of beams, including pulsed light, continuous light (CW), and quasi-continuous light. The operating wavelength of the light source may be 650 nm to 1150 nm, 800 nm to 1000 nm, 850 nm to 950 nm, or 1300 nm to 1600 nm. In one or more embodiments, the light source 102 may also include optical components optically coupled to the light source 102 for collimating or focusing the beam emitted by the light source 102. In one or more embodiments, the light source 102 includes at least one fiber laser. Each emitted beam from the light source 102 can be a continuous beam of light lasting for a certain period of time, or it can be one or more light pulses.

[0046] Scanner 104 is used to deflect the direction of the emitted beam from light source 102 to scan target object 120, achieving a wider emission field of view or scanning field of view. Scanner 104 can be any number of optical mirrors driven by any number of drivers. For example, scanner 104 may include plane mirrors, prisms, mechanical galvanometers, polarization gratings, optical phased arrays (OPA), and microelectromechanical systems (MEMS) galvanometers. For MEMS galvanometers, the mirror surface rotates or translates in one or two dimensions under electrostatic / piezoelectric / electromagnetic actuation. Driven by the drivers, scanner 104 guides the beam from the light source to various positions within the field of view to scan target object 120 within the field of view.

[0047] After the light beam is reflected from the target object 120, a portion of the reflected light returns to the lidar 100 and is received by the optical receiver 106. The optical receiver 106 receives and detects a portion of the reflected light from the target object 120 and generates a corresponding electrical signal. The optical receiver may include a receiving unit and associated receiving circuitry. Each receiving circuitry can be used to process the output electrical signal of the corresponding receiving unit. The receiving unit includes various forms of photodetectors or one-dimensional or two-dimensional arrays of photodetectors; correspondingly, the receiving circuitry may be a single circuit or an array of multiple circuits. The photodetector measures the power, phase, or time characteristics of the reflected light and generates a corresponding current output. The photodetector may be an avalanche diode (APD), a single-photon avalanche diode (SPAD), a PN-type photodiode, or a PIN-type photodiode.

[0048] Controller 108 is communicatively coupled to one or more of light source 102, scanner 104, and light receiver 106. Controller 108 can control whether and when light source 102 emits a light beam. Controller 108 can control scanner 104 to scan the light beam to a specific location. Controller 108 can process and analyze the electrical signals output by the light receiver to ultimately determine the position, velocity, and other characteristics of the target object 120. Controller 108 may include an integrated circuit (IC), application-specific integrated circuit (ASIC), microchip, microcontroller, central processing unit, graphics processing unit (GPU), digital signal processor (DSP), field-programmable gate array (FPGA), or other circuitry suitable for executing instructions or implementing logic operations. Instructions executed by controller 108 can be preloaded into an integrated or separate memory (not shown). The memory can store configuration data or commands for light source 102, scanner 104, or light receiver 106. The memory can also store electrical signals output from light receiver 106 or analysis results based on the output electrical signals. For example, the memory can store relevant information about stray light signals detected during the calibration period for use in subsequent operating periods. The memory may include random access memory (RAM), read-only memory (ROM), hard disk, optical disk, magnetic disk, flash memory, or other volatile or non-volatile memory. The controller 108 may include one or more processing circuits. In the case of multiple processing circuits, each processing circuit may have the same or different constructions and interact or cooperate with each other through electrical, magnetic, optical, acoustic, mechanical, or other means.

[0049] In one or more embodiments, the lidar 100 may further include an emitting lens 110. The emitting lens 110 may be used to expand a light beam emitted by the light source 102 and directed by the scanner 104. The emitting lens 110 may include diffractive optical elements (DOEs) for shaping, separating, or diffusing the light beam. The emitting lens 110 may be present independently or integrated into other components (e.g., the scanner 104 or the light source 102). The position of the emitting lens 110 in the emission optical path from the light source to the target object is not limited to... Figure 1 As shown in the diagram, the position can be changed to other locations. For example, the emitting lens can be arranged between the light source 102 and the scanner 104, so that the beam emitted by the light source 102 is first expanded by the emitting lens and then redirected by the scanner.

[0050] In one or more embodiments, the lidar 100 may further include a receiving lens 112. The receiving lens 112 is located in front of the light receiver 106 along the receiving path of the emitted light from the target object 120 to the light receiver 106. The receiving lens 112 may include an imaging system lens such that the focal point of the reflected beam is in front of or behind the detection surface of the photodetector or photodetector array, or exactly above the detection surface. In some cases, instead of existing as a separate component, the receiving lens 112 may also be integrated into the light receiver 106.

[0051] In one or more embodiments, the lidar 100 may further include a housing 114 for enclosing one or more of the aforementioned components therein for protection. In some embodiments, the housing 114 is made of an opaque material, and transparent areas or windows 116 may be provided on the housing 114 to allow the emitted or reflected beam to pass through. In other embodiments, the housing 114 itself is made of a transparent material, thereby allowing the emitted or reflected beam to pass through from any location.

[0052] In some embodiments, the lidar 100 may include a coaxial optical transceiver system. A coaxial optical transceiver system means that the transmission path from the light source 102 to the target object 120 at least partially overlaps with the reception path from the target object 120 to the optical receiver 106. For example, with... Figure 2 Unlike the previous method, the reflected beam can travel in the opposite direction through the scanner 104 to reach the optical receiver 106. For a coaxial optical transceiver system, not only does the exit angle of the emitted beam change with the deflection of the scanner, but the receiving angle of the light that the optical receiver can receive also changes synchronously with the deflection of the scanner. That is, the receiving field of view always remains equivalent to the scanning range of the emitted beam.

[0053] In other embodiments, the lidar 100 may include a non-coaxial optical transceiver system. A non-coaxial optical transceiver system means that the transmission path from the light source 102 to the target object 120 does not overlap with the reception path from the target object 120 to the optical receiver 106. For example, as... Figure 2 As shown, the reflected beam does not reach the optical receiver 106 via the scanner 104. For a non-coaxial optical transceiver system, although the exit angle of the emitted beam changes with the deflection of the scanner, the total receiving field of view of the optical receiver is fixed and does not change with the deflection of the scanner.

[0054] For non-coaxial lidar with a limited scanner rotation range (e.g., using a micro-electro-mechanical system (MEMS) scanning mirror), the field of view of a single light source is limited. Therefore, in order to increase the field of view, multiple light sources are generally used to increase the field of view of the lidar. The sub-fields of view formed by the multiple light sources are stitched together to form a complete lidar field of view.

[0055] Typically, a scanner presents a closed scanning pattern in space and repeats this scanning periodically. The lidar controls the scanner to produce different deflections according to the preset scanning pattern. After reaching the scanning endpoint, a period of time is needed for the scanner's deflection position to return to the scanning endpoint for the next scan; this process is called the retrace zone. Correspondingly, the process of the scanner's deflection position moving from the scanning endpoint to the scanning endpoint is called the scanning zone. The scanning zone and the retrace zone together constitute one frame of a lidar scan of the transmission field of view.

[0056] As an optional implementation of this invention, the ranging period is the measurement period of a single scanning point of the lidar; all ranging periods of the scanning area and the retrace area constitute one frame of the lidar.

[0057] When the scanner of a lidar is at different deflections, it can project light emitted from the light source at different angles, and the light at each different angle constitutes a scanning point of the lidar. The measurement period of a single scanning point of the lidar is the ranging period. Within the scanning area, the scanner generates different deflections according to a preset scanning pattern, thus forming different scanning points. The ranging period of all scanning points in the scanning area, plus the retrace period, constitutes one frame of the lidar. For example, Figure 4 This is a schematic diagram of the signal timing of the ranging period of a non-coaxial lidar.

[0058] In practical implementation, a Field Programmable Gate Array (FPGA) can be used to adjust the voltage of the MEMS scanning mirror, thereby controlling its rotation. In one optional embodiment, the MEMS scanning mirror moves with a 1kHz sine wave in the X-axis direction to form a horizontal scan line, and moves with a 10Hz triangular wave in the Y-axis direction to form a repeating scan frame. Macroscopically, the MEMS scanning mirror rotates continuously, but in reality, based on the characteristics of the MEMS scanning mirror chip, the MEMS scanning mirror driver chip drives the MEMS once every 6.25µs according to the set X and Y voltages. Therefore, the MEMS scanning mirror rotates by one angle every 6.25µs. Each time the MEMS scanning mirror rotates by one angle, each light source obtains a new emission position. According to theoretical calculations, the ranging time period for each light source is approximately 1.56µs, so the MEMS scanning mirror can support a maximum of four light sources emitting light when rotating by one angle. The control timing between the four light sources (light source A, light source B, light source C, and light source D) is as follows: Figure 3 As shown, the single ranging cycle in each light source ranging scanning area is 1.56 μs. Four ranging cycles constitute the scanning area of ​​the lidar. Within the scanning area, the lidar's MEMS scanning mirror moves from the scanning start point to the scanning end point, rotating by one angle every 6.25 μs.

[0059] In related technical solutions, to avoid occupying the scanning area time, when the lidar is a non-coaxial lidar, the optical receiver is usually in the form of an array. An array-type optical receiver contains multiple receiving channels. The echo signals of light reflected from the target object at different emission angles fall on different receiving channels, where they undergo photoelectric conversion and signal processing. Therefore, according to an optional embodiment of this disclosure, the method further includes one or more processors instructing the lidar to switch receiving channels during a channel switching period prior to the noise floor measurement period.

[0060] Optionally, the duration of the channel switching period allows the receiving channel to complete the switching and reach a stable state. When the receiving channel has completed the switching and is in a stable state, the measured noise floor value is more accurate. In specific implementations, the receiving channel switching can be completed and in a stable state can occur when no signal is transmitted.

[0061] If the lidar is a coaxial lidar, there is no need to set a channel switching period.

[0062] According to an alternative embodiment of the first embodiment of this disclosure, one or more processors instruct the lidar to determine the ranging start time during the light emission period.

[0063] For lidar using DToF (Direct Time-of-Flight) technology, it is necessary to measure the starting time of ranging when the laser is emitted and the ending time when the laser reflected from the object arrives, and then calculate the distance based on the time interval between the two times. Therefore, the starting time of ranging needs to be determined within the light emission period.

[0064] Methods for determining the start time of distance measurement include:

[0065] Method 1: The processor instructs the lidar to determine the ranging start time based on the time it takes for the emitted light from the received light source to be split.

[0066] Method 2: The processor instructs the lidar to collect the trigger signal Trig that emits the laser, and the trigger time of this signal is used as the starting time of ranging.

[0067] The problem with method two, which measures the start time, is that when the distance between the lidar and the target is small, the signal used to measure the start time will be superimposed on the signal of the reflected light, affecting the ranging accuracy or even making it impossible to distinguish the reflected light signal. Figure 5 The diagram shows (a) a schematic of the lidar distance measurement scheme and (b) a signal timing diagram when measuring near-field objects. It can be seen that when the lidar measures near-field objects, the trigger signal Trig is superimposed on the reflected light echo signal.

[0068] To address the issue of near-field signal superposition when measuring objects at close range using lidar, this disclosure provides a third method. The processor instructs the lidar's laser trigger controller to first issue a trigger copy signal (Trig_Ghost). The receiving circuit measures this signal to obtain the start time Ts. After an interval time Tw, a laser trigger signal Trig is issued, at which point the laser emits light. Subsequently, the receiving circuit measures the arrival time Tr of the light reflected from the object. The distance to the object is then D = (Tr - Ts - Tw) * c / 2, where c is the speed of light. Figure 6 (a) is a schematic diagram of a lidar distance measurement scheme using a Trigger Ghost signal and (b) is a signal timing diagram of measuring nearby objects using a Trigger Ghost signal.

[0069] For the scheme that uses a replica (Trig Ghost) signal to determine the measurement start time, the timing diagram can be found in [reference needed]. Figure 6The process involves several phases: a channel switching period (300ns), followed by a noise floor measurement period (256ns), during which the FPGA stores the data acquired by the analog-to-digital converter (ADC). The FPGA then outputs the stored data for noise floor measurement by other devices before proceeding to the light emission period (40ns). During this period, the ADC collects data, the FPGA outputs the stored data, and other devices perform TrigGhost detection to determine the measurement start time. The end of the light emission period is the emission point. At the emission point, the light source begins synchronous emission, and finally, echo detection is performed during the 964ns echo detection period. This method allows the current point's ranging calculation to directly use the noise floor calculation result, resulting in a more accurate final ranging value. However, the specific durations of these periods are merely examples and can be set to any value as needed; they are not limited in this embodiment.

[0070] According to an optional embodiment of this disclosure, the noise floor measurement can be obtained by averaging all sampling points acquired by the ADC during the optical noise floor measurement period.

[0071] See Figure 8 According to a second aspect of this disclosure, a lidar is provided, comprising: a light source 11 configured to emit light; a scanner 12 configured to guide the light to scan a target object; a light receiver 13 configured to detect light reflected by the target object; and a controller 14 communicatively coupled to the light source 11, the scanner 12 and the light receiver 13, the controller 14 being configured to perform the above-described noise floor measurement method.

[0072] According to an optional embodiment of this disclosure, the light source 11 in the lidar of this disclosure may include a semiconductor laser or a fiber laser.

[0073] According to a third aspect of this disclosure, a vehicle is provided that includes the aforementioned lidar.

[0074] According to a fourth aspect of this disclosure, an electronic device is provided, comprising: a processor and a memory for storing processor-executable instructions, wherein the processor is configured to execute the above-described lidar noise floor measurement method when the executable instructions in the memory are invoked.

[0075] According to optional embodiments of this disclosure, the controller 14 or processor may be implemented by one or more central processing units (CPUs), graphics processing units (GPUs), application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), general-purpose processors, microcontrollers (MCUs), microprocessors, or other electronic components.

[0076] According to a fifth aspect of this disclosure, a non-transitory computer-readable storage medium is provided, which, when instructions in the storage medium are executed by a processor of an electronic device, enables the electronic device to perform the aforementioned lidar noise floor measurement method.

[0077] It should be understood that the phrase "an embodiment" or "one embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this disclosure. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this disclosure, the sequence numbers of the above-described processes do not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this disclosure. The sequence numbers of the above-described embodiments are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0078] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0079] The features and benefits of this disclosure are illustrated by reference to the embodiments. Accordingly, this disclosure is not expressly intended to be limited to these exemplary embodiments that illustrate combinations of possible, non-limiting features, which may exist alone or in other combinations of features.

[0080] The embodiments described above are merely specific examples of this disclosure, used to illustrate the technical solutions of this disclosure, and not to limit it. The scope of protection of this disclosure is not limited thereto. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this disclosure; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure, and should all be covered within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A method for measuring the noise floor of a lidar system, characterized in that, The method includes: One or more processors instruct the lidar to detect noise floor during the noise floor measurement period, wherein the noise floor measurement period is set within the ranging cycle of the lidar, and multiple ranging cycles constitute the scanning area of ​​the lidar, within which the lidar scanner runs from the scanning start point to the scanning end point; The one or more processors instruct the lidar to emit outgoing light during the light emission period following the noise floor measurement period; The one or more processors instruct the lidar to detect the echo signal during the echo detection period following the light emission period.

2. The lidar noise floor measurement method according to claim 1, characterized in that, The lidar is a non-coaxial lidar, which includes multiple receiving channels; the method further includes: instructing the lidar to perform receiving channel switching during a channel switching period prior to the noise floor measurement period by one or more processors.

3. The lidar noise floor measurement method according to claim 1, characterized in that, The ranging period is the measurement period of a single scan point of the lidar; the ranging periods of all scan points in the scanning area and the retrace area constitute one frame of the lidar.

4. The lidar noise floor measurement method according to claim 2, characterized in that, The duration of the channel switching period allows the receiving channel to complete the switching and reach a stable state.

5. The lidar noise floor measurement method according to any one of claims 1 to 3, characterized in that, The one or more processors instruct the lidar to determine the ranging start time during the light emission period.

6. The lidar noise floor measurement method according to claim 5, characterized in that, Determining the starting time of ranging includes at least one of the following methods: The one or more processors instruct the lidar to determine the ranging start time based on the time of receiving the dispersed emitted light; The one or more processors instruct the lidar to determine the ranging start time based on the trigger signal of the emitted light; The one or more processors instruct the lidar to determine the ranging start time based on a copy signal of the trigger signal for emitting laser light, wherein the copy signal is a preset time earlier than the trigger signal.

7. A lidar, comprising: The light source is configured to emit light; A scanner is configured to direct the light emitted by the light source to scan a target object; A light receiver is configured to detect light reflected by the target object; as well as A controller, communicatively coupled to the light source, the scanner, and the light receiver, configured to perform the noise floor measurement method according to any one of claims 1 to 5.

8. The lidar according to claim 7, characterized in that, The light source includes a semiconductor laser or a fiber laser.

9. A vehicle comprising the lidar as described in claim 7 or 8.

10. An electronic device, characterized in that, The electronic device includes a processor and a memory for storing processor-executable instructions, wherein the processor is configured to perform the lidar noise floor measurement method as described in any one of claims 1 to 6 when the executable instructions in the memory are invoked.

11. A non-transitory computer-readable storage medium, characterized in that, When the instructions in the storage medium are executed by the processor of the electronic device, the electronic device is able to perform the lidar noise floor measurement method as described in any one of claims 1 to 6.

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