FMCW multi-channel lidar, method for generating same, and vehicle autonomous driving method using FMCW multi-channel lidar

Abstract

A method for generating a multi-channel optical system based on frequency modulated continuous wave (FMCW) light detection and ranging (LiDAR) according to the first aspect of the present disclosure comprises the steps of: inputting an optical signal having a periodically increasing / decreasing frequency; and generating a modulated optical signal having a modulation frequency different from the frequency by modulating the frequency.

Description

FMCW multi-channel lidar and its generation method, and vehicle autonomous driving method using FMCW multi-channel lidar

[0001] The present invention relates to a FMCW multi-channel lidar, a method for generating the same, and a method for autonomous driving a vehicle using the FMCW multi-channel lidar. This research was conducted with the support of the Korea Institute for Advancement of Technology (KIAT) with funding from the Ministry of Trade, Industry and Energy (Government) (Project ID: 2410008035; Project No.: P0025240; Research and Development Project: International Joint Technology Development Project; Research Project Title: Multi-channel (200,000 channels) Parallel Processing Solid-State FMCW Technology-Based LiDAR for Vehicles; Project Period: January 1, 2024 - December 31, 2024).

[0002] For reference, this application claims priority to Korean Patent Application No. 10-2024-0091566, filed on July 11, 2024. The entire contents of that application, which serves as the basis for this priority claim, are incorporated herein by reference.

[0003] LiDAR (light detection and ranging) is a sensor that transmits near-infrared light, visible light, and ultraviolet light to a target object, and detects the light that hits the target, reflects, and returns using an optical sensor to collect three-dimensional information (x, y, z) of the target object.

[0004] Typically, lidar uses light of a fixed frequency and can measure the time it takes for it to reflect back and the intensity of the light.

[0005] FMCW (frequency modulated continuous wave) lidar is similar to a general lidar that collects 3D information about the surrounding environment in terms of the way it transmits and receives light, but it differs from a general lidar in that it modulates the frequency of the light it transmits.

[0006] Since FMCW lidar emits light while rapidly changing its frequency, the emitted light can have a continuously changing frequency. When the emitted light hits an object or obstacle, some of the light may be reflected. The light reflected from the object or obstacle is collected by the FMCW lidar receiver, and the receiver can measure this frequency difference by comparing the frequency of the transmitted light with the frequency of the reflected light. If the object that hit the transmitted light is moving, a light with a frequency that has changed from the frequency of the transmitted light may be received depending on the degree of movement. Using the changed frequency, the relative velocity with the object caused by the Doppler effect can be calculated. In this way, FMCW lidar can measure the relative velocity value of a point in addition to the 3D information that a typical lidar can measure.

[0007] Conventional FMCW lidar, as shown in Figure 1, utilizes a method of increasing the number of lasers to form a multi-channel optical system with multiple frequencies. Therefore, since each optical system with a different frequency must be configured separately, the optical system of the FMCW lidar becomes complex and large.

[0008] Additionally, the more laser diodes (LDs) are used, the more difficult it can be to analyze the cause of a problem in the FMCW lidar.

[0009] Additionally, since the reflectivity and absorption of light vary with frequency, FMCW lidar using an optical system using a single frequency may have resolution limitations, such as not being able to identify specific objects.

[0010] The problem to be solved by the present invention is to provide an FMCW multi-channel lidar using a laser diode and a modulator that outputs a laser having one frequency, and a method for generating the same.

[0011] In addition, it provides a method for autonomous driving of a vehicle using FMCW multi-channel lidar.

[0012] However, the problems to be solved by the present invention are not limited to those mentioned above, and other problems to be solved that are not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention pertains from the description below.

[0013] A method for generating an FMCW multi-channel lidar according to one embodiment of the first aspect of the present invention includes a step of inputting an optical signal having a frequency that periodically increases and decreases, and a step of modulating the frequency to generate a modulated optical signal having a modulation frequency different from the frequency.

[0014] In the step of generating the above modulated optical signal, if the frequency continuously changes over time, a re-modulated optical signal having a re-modulation frequency different from the modulation frequency can be generated based on the continuously changed frequency.

[0015] In the step of generating the above modulated optical signal, the frequency can be modulated through four wave mixing.

[0016] In the step of generating the above modulated optical signal, the frequency can be modulated through a micro-ring modulator.

[0017] The length of the above micro ring modulator can be determined by considering the continuously changing frequency.

[0018] The above method may further include a step of outputting the optical signal and the modulated optical signal.

[0019] In the outputting step, an optical signal corresponding to a predetermined ratio of the total intensity of the sum of the intensity of the optical signal and the intensity of the modulated optical signal can be output.

[0020] In the step of generating the above modulated optical signal, the modulated optical signal can be generated based on a residual optical signal other than the output optical signal and the optical signal having a continuously changing frequency.

[0021] The method may further include a step of separating the output optical signal and the modulated optical signal into a Tx signal and a reference signal.

[0022] The method may further include a step of receiving an Rx signal reflected from an object by the Tx signal, and estimating at least one of position information and relative velocity of the object based on the reference signal and the Rx signal.

[0023] The above frequency can vary continuously over time.

[0024] The frequency can be continuously varied over time based on at least one of voltage, heat, sound waves, and electric fields.

[0025] In the step of generating the above-described modulated optical signal, the input optical signal is propagated through an optical path including a ring modulator, and the frequency is modulated to generate the above-described modulated optical signal, and four-wave mixing can be performed to generate a re-modulated optical signal having a re-modulation frequency different from the frequency and the modulation frequency based on the frequency and the modulation frequency.

[0026] A vehicle autonomous driving method using an FMCW multi-channel lidar according to another embodiment of the first aspect of the present invention includes the steps of transmitting a Tx signal from the FMCW multi-channel lidar, receiving a signal reflected by an object from the transmitted signal as an Rx signal, obtaining information on the object based on the Tx signal and the Rx signal, and controlling a driving direction and speed of the vehicle based on the information on the object.

[0027] An FMCW multi-channel lidar according to a second aspect of the present invention includes a light source that outputs an optical signal having a frequency that periodically increases and decreases, a modulator that modulates the frequency to generate a modulated optical signal having a modulation frequency different from the frequency, a transmitter that transmits the optical signal and the modulated optical signal to an external object, and a receiver that receives a reflected optical signal reflected from the object.

[0028] The above FMCW multi-channel lidar can transmit a Tx signal, receive a signal reflected by an object from the transmitted signal as an Rx signal, obtain information on the object based on the Tx signal and the Rx signal, and provide information for controlling the driving direction and speed of the vehicle based on the information on the object.

[0029] A non-transitory computer-readable recording medium storing computer-executable instructions according to a third aspect of the present invention, wherein the computer-executable instructions, when executed by a processor, cause the processor to perform a method comprising the steps of inputting an optical signal having a frequency that periodically increases and decreases and modulating the frequency to generate a modulated optical signal having a modulation frequency different from the frequency.

[0030] A computer program stored in a non-transitory computer-readable recording medium according to a fourth aspect of the present invention, wherein the computer program comprises instructions for causing the processor to perform a method, the method comprising the steps of inputting an optical signal having a frequency that periodically increases and decreases, and modulating the frequency to generate a modulated optical signal having a modulation frequency different from the frequency, when executed by the processor.

[0031] According to the present invention, the optical system of the FMCW lidar can be simplified as the optical system is unified into one.

[0032] Additionally, by using a unified optical system, the manufacturing cost of FMCW lidar can be reduced, and root cause analysis can be facilitated during failure analysis.

[0033] Additionally, the resolution of FMCW lidar can be improved by creating a multi-channel optical system using only one laser diode that outputs a single-frequency laser.

[0034] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0035] Figure 1 is an exemplary diagram showing a conventional FMCW lidar for implementing a multi-channel optical system.

[0036] Figure 2 is an example diagram showing four wave mixing.

[0037] Figure 3 is an exemplary diagram showing one embodiment for implementing four-wave mixing.

[0038] Figure 4 is an example diagram conceptually showing that signals having four different frequencies are output by inputting signals having two different frequencies.

[0039] Figure 5 is an exemplary diagram conceptually showing that signals having 12 different frequencies are output by inputting signals having 3 different frequencies.

[0040] Figure 6 is a conceptual illustration showing that when the ratio of output beams is low, the remaining beams continue to circle the ring, generating beams of new frequencies.

[0041] Fig. 7 is an exemplary diagram showing one embodiment for implementing the FMCW multi-channel lidar generation method of the present invention.

[0042] FIG. 8 is a flowchart exemplarily showing a method for generating an FMCW multi-channel lidar according to the first aspect of the present invention.

[0043] FIG. 9 is a block diagram exemplarily showing an FMCW multi-channel lidar according to a second aspect of the present invention.

[0044] Figure 10 is a block diagram exemplifying the functions of an FMCW multi-channel lidar generation program.

[0045] The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided solely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined solely by the scope of the claims.

[0046] When describing embodiments of the present invention, detailed descriptions of known functions or configurations will be omitted if they are deemed to unnecessarily obscure the gist of the invention. Furthermore, the terms described below are defined in light of their functions in the embodiments of the present invention and may vary depending on the intent or custom of the user or operator. Therefore, their definitions should be based on the overall content of this specification.

[0047] The terms used in this specification will be briefly explained, and the present invention will be described in detail.

[0048] The terms used in this specification have been selected from widely used, current terms, taking into account the functions of the present invention. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, in which case their meanings will be described in detail in the relevant description of the invention. Therefore, the terms used in this invention should not be defined simply as names, but rather based on their inherent meanings and the overall content of the present invention.

[0049] When a part of a specification is said to 'include' a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0050] Also, the term 'part' used in the specification means a software or hardware component such as an FPGA or ASIC, and the 'part' performs certain functions. However, the 'part' is not limited to software or hardware. The 'part' may be configured to reside on an addressable storage medium or may be configured to play one or more processors. Thus, as an example, the 'part' includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within the components and 'parts' may be combined into a smaller number of components and 'parts' or further separated into additional components and 'parts'.

[0051] Below, with reference to the attached drawings, an embodiment of the present invention is described in detail so that a person having ordinary skill in the art to which the present invention pertains can easily practice it.

[0052] Figure 2 is an example diagram showing four wave mixing.

[0053] Four-wave mixing refers to an optical signal phenomenon in which interference between multiple frequencies causes signals to be generated at undesired frequencies or the intensity of an optical signal to be attenuated. Using four-wave mixing, a single laser frequency can generate lasers of various frequencies.

[0054] Figure 3 is an exemplary diagram showing one embodiment for implementing four-wave mixing.

[0055] As shown in Fig. 3, the outputs of two laser diodes (LD1, LD2) having two different frequencies can be input to a modulator to generate two new lasers having frequencies different from the input frequencies. Here, the modulator can be configured to implement four-wave mixing. For example, the modulator can be configured in the form of a micro-ring modulator. In this case, the length of the micro-ring modulator can be determined in consideration of the wavelength of the output laser.

[0056] When the frequency of the seed laser output from LD1 and LD2 is modulated, a laser modulated with a new frequency can be additionally generated.

[0057] Next, a certain percentage of the generated lasers can be used as Tx, and the remaining percentage of lasers can be extracted separately and used as a reference signal. At this time, an interference signal can be obtained for each laser wavelength using a wavelength division technique, etc. Here, Tx can refer to a transmission signal for detecting an object, and Rx can refer to a reception signal reflected from the object and received.

[0058] Figure 4 is an example diagram conceptually showing that signals having four different frequencies are output by inputting signals having two different frequencies.

[0059] f1 and f2 represent two input signals with different frequencies. By mixing the two input signals, two additional signals with new frequencies (f1-f2, f1+f2) can be generated. In this case, the more input signals there are, the more diverse the frequency of the output signal can be.

[0060] Figure 5 is an exemplary diagram conceptually showing that signals having 12 different frequencies are output by inputting signals having 3 different frequencies.

[0061] f1, f2, and f3 represent signals with three different frequencies that have been input. By mixing the three input signals, nine additional signals with new frequencies (2f1-f3, 2f1-f2, f1+f2-f3, f1+f3-f2, 2f2-f3, 2f3-f2, 2f2-f1, f2+f3-f1, 2f3-f1) can be generated. As can be seen in FIGS. 4 and 5, synthesizing a large number of frequencies can generate an even larger number of new frequencies.

[0062] If the frequency of the input signal, such as the laser in an FMCW lidar, varies continuously over time, the frequency of the newly generated signal can also vary continuously over time. The relationship between the wavelength and frequency of light can be expressed as follows.

[0063]

[0064] Here, c is the speed of light, represents the wavelength of light, and f represents the frequency of light. In other words, if the wavelength of the input light is swept to modulate its frequency, the derived frequencies can also be modulated. At this time, the wavelength can be swept using voltage, heat, sound waves, electric fields, etc.

[0065] Figure 6 is a conceptual illustration showing that when the ratio of output beams is low, the remaining beams continue to circle the ring, generating beams of new frequencies.

[0066] In Fig. 6, a% represents the proportion of output light, and (100-a)% represents the proportion of remaining light remaining in the ring.

[0067] If the ratio of output light is low, light corresponding to the remaining frequencies can continue to circulate around the ring, generating new frequencies. The input light can also be frequency-modulated as its wavelength is swept. Through this method, light corresponding to many frequencies can be generated in a regular manner.

[0068] Fig. 7 is an exemplary diagram showing one embodiment for implementing the FMCW multi-channel lidar generation method of the present invention.

[0069] FMCW lidar can transmit reflected light and receive the reflected light that is reflected back from an object. By analyzing the reflected light, FMCW lidar can measure the time it takes for the transmitted light to reflect back and the intensity of the reflected light. FMCW lidar can transmit light while varying its frequency. Therefore, it can transmit light with a continuously changing frequency. The light reflected from an object or obstacle can be received by the FMCW lidar receiver. The FMCW lidar receiver can measure the frequency difference by comparing the frequency of the transmitted light with the frequency of the reflected light. Since the reflectivity and absorption of light vary depending on the frequency, FMCW lidar using an optical system using a single frequency may have resolution limitations, such as the inability to identify specific objects. To improve these limitations, a multi-channel optical system can be used in FMCW lidar.

[0070] The FMCW multi-channel lidar of FIG. 7 may include a laser diode (LD1) that outputs a laser having a single frequency, a modulator that modulates the frequency of the laser having the single frequency to generate a plurality of lasers having various frequencies, a beam splitter that separates a beam output from the modulator into a reference beam and a Tx beam, an interferometer that receives an Rx beam that is received when the reference beam and the Tx beam are reflected from an object, and a photodiode (PD) configured for each frequency using light output from the interferometer.

[0071] When a laser having a single frequency is input to a modulator, the modulator can modulate the frequency of the input laser to generate a frequency-modulated laser. Furthermore, the modulator can mix the frequency of the input laser with the frequency-modulated laser to generate a new four-wave mixed laser. The frequency of the laser input to an FMCW lidar can vary continuously. Therefore, as the frequency of the input laser varies continuously, the frequency generated by the modulator can increase in diversity. Through this process, multiple lasers having various frequencies can be generated using a laser diode that outputs a laser having a single frequency and a modulator.

[0072] Fig. 8 is a flowchart exemplarily showing a method for generating an FMCW multi-channel lidar according to a first aspect of the present invention. Hereinafter, the FMCW multi-channel lidar generation method will be described on the assumption that it is performed by an FMCW multi-channel lidar.

[0073] As shown in FIG. 8, the FMCW multi-channel lidar generation method according to the first aspect of the present invention includes a step (S810) of inputting an optical signal having a frequency that periodically increases and decreases, and a step (S820) of modulating the frequency to generate a modulated optical signal having a modulation frequency different from the frequency.

[0074] FIG. 9 is a block diagram exemplarily showing an FMCW multi-channel lidar according to a second aspect of the present invention.

[0075] As shown in FIG. 9, the FMCW multi-channel lidar (900) may include an input unit (910), an output unit (920), a processor (930), a memory (940), and a communication unit (960).

[0076] Hereinafter, for the convenience of explanation, an example is provided in which an FMCW multi-channel lidar (900) includes an input unit (910), an output unit (920), a processor (930), a memory (940), and a communication unit (960), but the present invention is not limited thereto. That is, each unit configuration may be provided outside the FMCW multi-channel lidar (900) and may operate in a manner that interacts with the FMCW multi-channel lidar (900).

[0077] The input unit (910) may include a user interface for receiving commands, information, etc. used to control the FMCW multi-channel lidar (900). In addition, the input unit (910) may be a hardware device (e.g., a keyboard, a touch pad, a voice recognition microphone, etc.) that can directly receive commands, information, etc. used to control the FMCW multi-channel lidar (900).

[0078] The input unit (910) may include a light receiving module capable of receiving a reflected light reflected from an object from a transmitted light.

[0079] In one embodiment, the input unit (910) can receive information required for the FMCW multi-channel lidar generation method from a user.

[0080] The output unit (920) may include a light transmission module that transmits light whose frequency is modulated around the FMCW multi-channel lidar (900).

[0081] The output unit (920) can provide information related to an object, such as information appearing during the FMCW multi-channel lidar generation process, information about the generation result, object location information, and relative velocity, to the user as visual information through an interface or display device.

[0082] The processor (930) can control the overall operation of the FMCW multi-channel lidar (900) to perform the present invention.

[0083] The processor (930) can load the FMCW multi-channel lidar generation program (950) and information necessary for executing the FMCW multi-channel lidar generation program (950) from the memory (940) to execute the FMCW multi-channel lidar generation program (950).

[0084] The processor (930) can control to store data received from an external device through the communication unit (960) in the memory (940). In addition, the processor (930) can control to transmit information related to an object, such as information appearing during the FMCW multi-channel lidar generation process, information about the generation result, position information of the object, and relative velocity, to the external device through the communication unit (960).

[0085] The processor (930) may refer to a processing device such as a microprocessor, a central processing unit (CPU), a graphic processing unit (GPU), a processor core, a multiprocessor, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a micro controller unit (MCU), but is not limited to the above-described embodiment.

[0086] The memory (940) can store the FMCW multi-channel lidar generation program (950) and information required for executing the FMCW multi-channel lidar generation program (950). In addition, the memory (940) can also store the processing results by the processor (930).

[0087] The FMCW multi-channel lidar generation program (950) may mean software including commands programmed to perform the method according to the present invention.

[0088] The memory (940) can store information related to an object, such as information generated during the FMCW multi-channel lidar generation process, information on the generation result, object location information, and relative velocity. In addition, the memory (940) can store information received from an external device via the communication unit (960).

[0089] Memory (940) may refer to a computer-readable recording medium, such as a magnetic media such as a hard disk, a floppy disk, and a magnetic tape, an optical media such as a CD-ROM, a DVD, a magneto-optical media such as a floptical disk, a random access memory such as a dynamic random access memory (DRAM) and a static random access memory (SRAM), and a hardware device specifically configured to store and execute program instructions such as a flash memory, but is not limited to the above-described embodiment.

[0090] The communication unit (960) may be a wireless communication module capable of performing wireless communication by adopting a communication method such as CDMA, GSM, W-CDMA, TD-SCDMA, WiBro, LTE, EPC, 5G, wireless LAN, Wi-Fi, Bluetooth, Zigbee, WFD (Wi-Fi direct), UWB (ultra wide band), infrared communication (IrDA; infrared data association), BLE (Bluetooth low energy), or NFC (near field communication), but is not limited to the above-described embodiment.

[0091] Additionally, information input and output through the input unit (910) and output unit (920), information stored in the memory (940), and information transmitted and received through the communication unit (960) include all information related to the present invention, and are not limited to the above-described embodiment.

[0092] The functions or operations of the FMCW multi-channel lidar generation program (950) will be examined in detail with reference to Fig. 10.

[0093] Figure 10 is a block diagram exemplifying the functions of an FMCW multi-channel lidar generation program.

[0094] As shown in Fig. 10, the FMCW multi-channel lidar generation program (950) may include an optical signal input unit (1010), an optical signal generation unit (1020), an optical signal output unit (1030), an optical signal separation unit (1040), and an estimation unit (1050). The optical signal input unit (1010), the optical signal generation unit (1020), the optical signal output unit (1030), the optical signal separation unit (1040), and the estimation unit (1050) are exemplary divisions of the functions of the FMCW multi-channel lidar generation program (950), and are not limited thereto.

[0095] According to an embodiment, the functions of the optical signal input unit (1010), the optical signal generation unit (1020), the optical signal output unit (1030), the optical signal separation unit (1040), and the estimation unit (1050) can be merged / separated, and can be implemented as a series of commands included in at least one program.

[0096] The optical signal input unit (1010), optical signal generation unit (1020), optical signal output unit (1030), optical signal separation unit (1040), and estimation unit (1050) may be implemented by a processor (930), and may mean a data processing device built into hardware having a physically structured circuit to perform a function expressed by a code or command included in an FMCW multi-channel lidar generation program (950) stored in a memory (940).

[0097] The optical signal input unit (1010) can receive an optical signal having a frequency that periodically increases and decreases. In this case, the optical signal may refer to an FMCW lidar-based optical signal. In other words, the optical signal may refer to a laser light source included in the FMCW lidar.

[0098] Frequency can vary continuously over time. For example, frequency can vary continuously over time based on at least one of voltage, heat, sound, and electric fields.

[0099] The optical signal generation unit (1020) can modulate the frequency to generate a modulated optical signal having a modulation frequency different from the frequency.

[0100] The optical signal generation unit (1020) can generate a re-modulation optical signal having a re-modulation frequency different from the modulation frequency based on the continuously changed frequency when the frequency continuously changes over time.

[0101] The optical signal generation unit (1020) can modulate the frequency through four-wave mixing. For example, the optical signal generation unit (1020) can modulate the frequency through a micro-ring modulator. At this time, the length of the micro-ring modulator can be determined in consideration of the continuously changing frequency. In other words, the length of the micro-ring modulator can be determined in consideration of the wavelength of the laser light source included in the FMCW lidar.

[0102] The optical signal output unit (1030) can output an optical signal and a modulated optical signal.

[0103] The optical signal output unit (1030) can output an optical signal corresponding to a predetermined ratio of the total intensity of the sum of the intensity of the optical signal and the intensity of the modulated optical signal. The optical signal generation unit (1020) can generate a modulated optical signal based on a residual optical signal other than the output optical signal and an optical signal having a continuously changing frequency.

[0104] The optical signal separation unit (1040) can separate the output optical signal and modulated optical signal into a Tx signal and a reference signal. Here, Tx can mean a transmission signal for detecting an object, and Rx can mean a reception signal reflected from an object and received.

[0105] The estimation unit (1050) receives an Rx signal that is received when a Tx signal is reflected from an object, and can estimate at least one of the position information and relative velocity of the object based on the reference signal and the Rx signal.

[0106] As described above, according to the present invention, the optical system of the FMCW lidar can be simplified as the optical system is unified into one.

[0107] Additionally, by using a unified optical system, the manufacturing cost of FMCW lidar can be reduced, and root cause analysis can be facilitated during failure analysis.

[0108] Additionally, the resolution of FMCW lidar can be improved by creating a multi-channel optical system using only one laser diode that outputs a single-frequency laser.

[0109] The embodiments of the present invention described above may be implemented through various means. For example, the embodiments of the present invention may be implemented using hardware, firmware, software, or a combination thereof.

[0110] The combination of each block of the block diagram and each step of the flowchart attached to the present invention may be performed by computer program instructions. These computer program instructions may be installed in an encoding processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, so that the instructions executed by the encoding processor of the computer or other programmable data processing equipment create a means for performing the functions described in each block of the block diagram or each step of the flowchart. These computer program instructions may also be stored in a computer-available or computer-readable memory that can direct a computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can also produce an article of manufacture that includes an instruction means for performing the functions described in each block of the block diagram or each step of the flowchart. Since the computer program instructions can also be installed on a computer or other programmable data processing device, a series of operational steps are performed on the computer or other programmable data processing device to create a computer-executable process, and the instructions that cause the computer or other programmable data processing device to perform the steps for executing the functions described in each block of the block diagram and each step of the flowchart can also provide steps for executing the functions described in each block of the block diagram and each step of the flowchart.

[0111] Additionally, each block or step may represent a module, segment, or portion of code that includes one or more executable instructions for performing a specific logical function(s). In some embodiments, the functions mentioned in the blocks or steps may occur out of order. For example, two blocks or steps depicted in succession may actually be performed substantially simultaneously, or the blocks or steps may sometimes be performed in reverse order depending on the corresponding function.

[0112] The above description is merely an illustrative illustration of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential quality of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate, rather than limit, the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

Claims

1. In a method for generating FMCW multi-channel LiDAR performed by FMCW (frequency modulated continuous wave) multi-channel LiDAR (light detection and ranging), A step of inputting an optical signal having a frequency that periodically increases and decreases; and comprising a step of modulating the frequency to generate a modulated optical signal having a modulation frequency different from the frequency; How to create an FMCW multi-channel lidar.

2. In paragraph 1, In the step of generating the above modulated optical signal, When the frequency changes continuously over time, a re-modulation optical signal having a re-modulation frequency different from the modulation frequency is generated based on the continuously changed frequency. How to create an FMCW multi-channel lidar.

3. In paragraph 1, In the step of generating the above modulated optical signal, Modulating the above frequency through four wave mixing, How to create an FMCW multi-channel lidar.

4. In paragraph 1, In the step of generating the above modulated optical signal, Modulating the frequency through a micro-ring modulator, How to create an FMCW multi-channel lidar.

5. In paragraph 4, The length of the above micro ring modulator is determined by considering the continuously changing frequency, if the frequency changes continuously over time. How to create an FMCW multi-channel lidar.

6. In paragraph 1, The above method, Further comprising a step of outputting the optical signal and the modulated optical signal, How to create an FMCW multi-channel lidar.

7. In paragraph 6, In the above outputting step, Outputting an optical signal corresponding to a predetermined ratio of the total intensity of the sum of the intensity of the optical signal and the intensity of the modulated optical signal, How to create an FMCW multi-channel lidar.

8. In paragraph 7, In the step of generating the above modulated optical signal, When the frequency changes continuously over time, the modulated optical signal is generated based on the residual optical signal other than the output optical signal and the optical signal having the continuously changing frequency. How to create an FMCW multi-channel lidar.

9. In paragraph 6, The above method, Further comprising a step of separating the output optical signal and the modulated optical signal into a Tx signal and a reference signal. How to create an FMCW multi-channel lidar.

10. In paragraph 9, The above method, Further comprising a step of receiving an Rx signal reflected from an object by the Tx signal, and estimating at least one of position information and relative velocity of the object based on the reference signal and the Rx signal. How to create an FMCW multi-channel lidar.

11. In paragraph 1, The above frequency varies continuously over time, How to create an FMCW multi-channel lidar.

12. In paragraph 11, The frequency varies continuously over time based on at least one of voltage, heat, sound waves, and electric fields. How to create an FMCW multi-channel lidar.

13. In paragraph 1, In the step of generating the above modulated optical signal, The input optical signal is propagated through an optical path including a ring modulator, and the frequency is modulated to generate the modulated optical signal, and four wave mixing is performed to generate a re-modulated optical signal having a re-modulation frequency different from the frequency and the modulation frequency based on the frequency and the modulation frequency. How to create an FMCW multi-channel lidar.

14. A light source that outputs a light signal having a frequency that periodically increases and decreases; A modulator that modulates the frequency to generate a modulated optical signal having a modulation frequency different from the frequency; A transmitter that transmits the optical signal and the modulated optical signal to an external object; and Including a receiving end that receives a reflected light signal reflected from the object, FMCW multi-channel lidar.

15. In paragraph 14, The above modulator, When the frequency changes continuously over time, a re-modulation optical signal having a re-modulation frequency different from the modulation frequency is generated based on the continuously changed frequency. FMCW multi-channel lidar.

16. In paragraph 14, The above modulator, Modulating the above frequency through four wave mixing, FMCW multi-channel lidar.

17. In paragraph 14, The above modulator, including a micro-ring modulator FMCW multi-channel lidar.

18. In paragraph 17, The length of the above micro ring modulator is determined by considering the continuously changing frequency, if the frequency changes continuously over time. FMCW multi-channel lidar.

19. In paragraph 14, The above FMCW multi-channel lidar is, Transmit the Tx signal, Receive the reflected signal from the object of the transmitted signal as an Rx signal, Obtain information about the object based on the Tx signal and the Rx signal, Providing information for controlling the driving direction and speed of the vehicle based on the information of the above object. FMCW multi-channel lidar.

20. A non-transitory computer-readable recording medium storing computer-executable instructions, wherein the computer-executable instructions, when executed by a processor, A step of inputting an optical signal having a frequency that periodically increases and decreases; and A method comprising the step of causing the processor to perform a method including modulating the frequency to generate a modulated optical signal having a modulation frequency different from the frequency. Non-transitory computer-readable recording medium.

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