CN220983503U

CN220983503U - Laser radar

Info

Publication number: CN220983503U
Application number: CN202322814605.1U
Authority: CN
Inventors: 莫嘉明; 曹璨; 向少卿
Original assignee: Zhejiang Hesi Technology Co ltd
Current assignee: Zhejiang Hesi Technology Co ltd
Priority date: 2023-10-19
Filing date: 2023-10-19
Publication date: 2024-05-17
Anticipated expiration: 2033-10-19

Abstract

The present disclosure provides a lidar comprising: a light source configured to emit an optical signal; the optical communication receiving unit is configured to receive the optical signal, convert the optical signal into an initial electrical signal, convert the initial electrical signal into a first differential signal and a second differential signal, and generate a digital signal corresponding to the optical signal according to the first differential signal and the second differential signal, wherein the digital signal is used for representing information carried by the optical signal. By adopting the technical scheme, the stability of digital signal generation in the optical communication receiving link can be improved, and the working performance of the laser radar is further improved.

Description

Laser radar

Technical Field

The disclosure relates to the technical field of lidar, and in particular relates to a lidar.

Background

With the rise of autopilot technology, laser radar (Light Detection AND RANGING, light) is becoming more and more important as an important environmental perception component.

The working principle of the laser radar is as follows: the laser radar emits detection light to the surrounding environment, and collects echo light reflected by external targets (such as vehicles, pedestrians, buildings and the like) to obtain echo signals, and after data processing is performed on the detection light signals and the echo signals, relevant information of the targets, such as parameters of distance, azimuth, height, speed, gesture, even shape and the like of the targets, can be obtained, so that target detection is realized.

Some lidars use wireless optical communication technology to realize data transmission between upper and lower warehouse boards of the lidar. Therefore, how to provide a technical solution to improve the stability of digital signal generation in an optical communication receiving link is a problem to be solved.

Disclosure of utility model

In view of this, the present disclosure provides a lidar capable of improving the stability of digital signal generation in an optical communication receiving link, thereby improving the working performance of the lidar.

The present disclosure provides a lidar comprising:

A light source configured to emit an optical signal;

The optical communication receiving unit is configured to receive the optical signal, convert the optical signal into an initial electrical signal, convert the initial electrical signal into a first differential signal and a second differential signal, and generate a digital signal corresponding to the optical signal according to the first differential signal and the second differential signal, wherein the digital signal is used for representing information carried by the optical signal.

Optionally, the optical communication receiving unit includes:

A detection module configured to detect the optical signal and convert the optical signal into the initial electrical signal;

A differential module configured to convert the initial electrical signal into the first differential signal and the second differential signal;

And the digital signal generating module is configured to generate a digital signal corresponding to the optical signal according to the first differential signal and the second differential signal.

Optionally, a differential conversion ratio of the differential module is adjustable, and the differential conversion ratio is used for representing the amplification factor of the initial electric signal.

Optionally, the differential module includes: at least one balun, any balun comprising a first coil and a second coil coupled to each other, wherein the first coil is coupled to the detection module; the second coil is coupled to the digital signal generation module.

Optionally, the differential conversion proportion of the differential module is determined according to the resistance value of the first coil and the resistance value of the second coil in the balun.

Optionally, the at least one balun is a plurality of baluns, and the transformation ratio of each baluns is different, the transformation ratio being a ratio of a resistance value of the first coil and a resistance value of the second coil in the baluns.

Optionally, the differential module further includes a plurality of gating channels, one gating channel corresponding to each balun, and the gating channel is coupled between the corresponding balun and the detection module; the gating channel is configured to conduct a path between the corresponding balun and the detection module when gated; the conversion ratio of the balance-unbalance converter in the conducting state is the current differential conversion ratio of the differential module.

Optionally, the digital signal generating module includes a gain sub-module and a comparison sub-module, wherein:

The gain submodule is respectively coupled with the differential module, the comparison submodule and the power supply, and is configured to amplify the first differential signal and the second differential signal, and convert the types of the first differential signal and the second differential signal to obtain a first differential voltage and a second differential voltage;

The comparison submodule is configured to output corresponding digital signals according to the first differential voltage and the second differential voltage.

Optionally, the gain submodule includes a first gain element and a second gain element, wherein:

The first gain device is respectively coupled with the differential module, the first input end of the comparison sub-module and the power supply, and is configured to amplify the first differential signal and convert the type of the first differential signal to obtain the first differential voltage;

The second gain device is coupled with the differential module, the second input end of the comparison sub-module and the power supply respectively, and is configured to amplify the second differential signal and convert the type of the second differential signal to obtain the second differential voltage.

Optionally, the first gain device includes: the first end of the first resistor is grounded, and the second end of the first resistor is respectively coupled with the first end of the second resistor, the first input end of the comparison sub-module and the first output end of the differential module; a second end of the second resistor is coupled with the power supply;

the second gain device includes: a third resistor and a fourth resistor, wherein a first end of the third resistor is coupled with the power supply, and a second end of the third resistor is respectively coupled with the first end of the fourth resistor, a second input end of the comparison sub-module and a second output end of the differential module; the second end of the fourth resistor is grounded.

Optionally, at least two of the first resistor, the second resistor, the third resistor and the fourth resistor have different resistance values.

Optionally, the resistance of the first resistor is the same as the resistance of the third resistor, and the resistance of the second resistor is the same as the resistance of the fourth resistor.

Optionally, the resistance value of at least one of the first resistor, the second resistor, the third resistor and the fourth resistor is adjustable.

Optionally, the comparing submodule is configured to output a first digital signal when the first differential voltage is greater than the second differential voltage; and outputting a second digital signal when the first differential voltage is smaller than the second differential voltage.

Optionally, the detection module comprises a photodetector.

Optionally, the optical communication receiving unit further includes: and the direct current source module is coupled with the detection module and is configured to provide direct current bias voltage for the detection module.

Optionally, the optical communication receiving unit further includes: and the first filtering module is coupled with the direct current source module, the detection module and the differential module respectively and is configured to filter noise in the direct current bias voltage.

Optionally, the optical communication receiving unit further includes: the second filtering module is arranged between the differential module and the digital signal generating module and is configured to filter noise in the first differential signal and the second differential signal.

Optionally, the second filtering module includes a common mode inductance.

Optionally, the laser radar further comprises: and the data processing unit is coupled with the optical communication receiving unit and is configured to process the digital signal so as to obtain information carried in the optical signal.

The laser radar provided by the disclosure may include a light source and an optical communication receiving unit, where the optical communication receiving unit may receive an optical signal emitted by the light source and convert the optical signal into an initial electrical signal, and further the optical communication receiving unit may convert the initial electrical signal into a first differential signal and a second differential signal, and based on the first differential signal and the second differential signal, a digital signal corresponding to the optical signal may be generated, and since the digital signal may be used to characterize information carried by the optical signal, detected target parameter information may be obtained. By adopting the laser radar, the first differential signal and the second differential signal have strong anti-interference performance, so that the interference can be reduced by adopting a transmission mode of the differential signals, the stability of digital signal generation in an optical communication receiving link is improved, and the working performance of the laser radar is further improved.

Further, since the differential conversion ratio of the differential module is adjustable, and the differential conversion ratio can be used for representing the amplification factor of the initial electrical signal, the amplification factor of the initial electrical signal can be controlled by adjusting the differential conversion ratio of the differential module, so that differential signals with different amplitudes can be obtained, and the optical communication receiving unit can be suitable for different scenes.

Further, the differential module may include at least one balun, either of which may include a first coil and a second coil coupled to each other, wherein the first coil is coupled to the detection module; the second coil is coupled to the digital signal generation module. By adopting at least one balance-unbalance converter, a first differential signal and a second differential signal with balanced states can be obtained, so that the anti-interference performance of the first differential signal and the second differential signal can be improved, the stability of digital signal generation is further improved, and the communication quality is further improved.

Further, the digital signal generation module may include a gain sub-module and a comparison sub-module, wherein: the gain submodule can amplify the first differential signal and the second differential signal, convert the types of the first differential signal and the second differential signal to obtain the first differential voltage and the second differential voltage, and then the comparison submodule can output corresponding digital signals according to the first differential voltage and the second differential voltage. The gain of the digital signal can be improved by amplifying the first differential signal and the second differential signal, and the digital signal corresponding to the optical signal can be obtained by converting the types of the first differential signal and the second differential signal and adapting the types to the comparison sub-module.

Further, the optical communication receiving unit may further include a first filtering module, which may filter noise in the dc bias voltage, so as to further improve stability of digital signal generation.

Further, the optical communication receiving unit may further include a second filtering module, which may filter noise in the first differential signal and the second differential signal, so as to further improve stability of digital signal generation.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings used in the embodiments of the present disclosure or the description of the prior art will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present disclosure, and other drawings may be obtained according to these drawings without inventive effort to a person of ordinary skill in the art.

Fig. 1 is a schematic structural diagram of a lidar according to an embodiment of the disclosure;

fig. 2 is a schematic structural diagram of an optical communication receiving unit according to an embodiment of the disclosure;

Fig. 3 is a schematic structural diagram of another optical communication receiving unit according to an embodiment of the disclosure;

fig. 4 is a schematic structural diagram of a digital signal generating module according to an embodiment of the disclosure;

fig. 5 is a waveform diagram of a corresponding monitoring point in an optical communication receiving unit according to an embodiment of the disclosure;

Fig. 6 is a schematic structural diagram of yet another optical communication receiving unit in an embodiment of the disclosure;

fig. 7 is a schematic structural diagram of an optical communication receiving unit in a specific application scenario in an embodiment of the disclosure.

Detailed Description

As described in the background art, when the laser radar adopts wireless optical communication, stability and reliability of the number transmission need to be ensured.

In order to solve the technical problem, the disclosure provides a laser radar, which can convert an optical signal emitted by a light source into an initial electrical signal and convert the initial electrical signal into a first differential signal and a second differential signal, and because the first differential signal and the second differential signal have strong anti-interference performance, the interference can be reduced by adopting a transmission mode of the differential signal, so that the stability of digital signal generation in an optical communication receiving link can be improved, and the working performance of the laser radar is further improved.

For a better understanding and appreciation of the disclosure, those skilled in the art will be gained through a more complete description of the concepts, aspects, principles, and advantages thereof, etc. in connection with the accompanying drawings.

The present disclosure provides a lidar, such as a schematic diagram of the structure of the lidar shown in fig. 1, in some embodiments, the lidar 100 may include: a light source 110 and an optical communication receiving unit 120, wherein:

The light source 110 is configured to emit an optical signal;

The optical communication receiving unit 120 is configured to receive the optical signal, convert the optical signal into an initial electrical signal, convert the initial electrical signal into a first differential signal and a second differential signal, and generate a digital signal corresponding to the optical signal according to the first differential signal and the second differential signal, where the digital signal is used to characterize information carried by the optical signal.

In a specific implementation, when the light source 110 emits an optical signal, the optical communication receiving unit 120 may convert the received optical signal into an initial electrical signal, and perform differential processing on the initial electrical signal to obtain a first differential signal and a second differential signal corresponding to the initial electrical signal, and because the anti-interference performance of the first differential signal and the second differential signal is strong, the transmission mode of the differential signal is adopted, so that interference can be reduced, and further, in the process of according to the first differential signal and the second differential signal, the influence of the external environment on the digital signal can be reduced, the stability of digital signal generation in the optical communication receiving link is improved, and further, the working performance of the laser radar is improved.

The differential signals refer to signals with the same amplitude and opposite phases generated on two branches in the optical communication receiving link, so that after the initial electrical signals are subjected to differential processing in the embodiment of the disclosure, two signals which are differential signals are obtained, namely a first differential signal and a second differential signal.

In order for those skilled in the art to better understand and practice embodiments of the present disclosure, some specific examples are given below for specific implementations of lidar in embodiments of the present disclosure.

In some embodiments of the present disclosure, the light source may be implemented by a light emitting diode, LED, which is illustrated in the following examples.

As an alternative example, the light source may include one LED or may include a plurality of LEDs, and the plurality of LEDs may be configured according to a preset connection relationship.

In other alternative examples, the light source may also be implemented by a laser diode LD, and the embodiments of the present disclosure are not limited to the type of light source, as long as it can emit an optical signal when applied to a lidar.

In a specific implementation, information can be transmitted by emitting a light signal with brightness change through the light source, and then the optical communication receiving unit can obtain a digital signal corresponding to the light signal according to the light signal with brightness change.

In some embodiments of the present disclosure, with continued reference to fig. 1, the optical communication receiving unit 120 may include: a detection module 121, a difference module 122 and a digital signal generation module 123, wherein:

The detection module 121 is configured to detect the optical signal and convert the optical signal into the initial electrical signal;

The differential module 122 is configured to convert the initial electrical signal into the first differential signal and the second differential signal;

The digital signal generating module 123 is configured to generate a digital signal corresponding to the optical signal according to the first differential signal and the second differential signal.

In an alternative implementation, the detection module 121 may detect the light signal with the brightness change emitted by the light source 110 in real time, when the light signal is detected, the detection module 121 may convert the detected light signal into an initial electrical signal, the differential module 122 may perform differential processing on the initial electrical signal to obtain a corresponding first differential signal and a corresponding second differential signal, and further the digital signal generating module 123 may generate, according to the first differential signal and the second differential signal, a digital signal corresponding to the light signal, and because the digital signal may be used to characterize the brightness change of the light signal, and may further characterize the information carried by the light signal, by subsequently processing the digital signal, information carried by the light signal, such as point cloud data, control signals detected by the laser radar, and so on, may be obtained.

By adopting the optical communication receiving unit with the structure, the anti-interference performance in the transmission process of the initial electric signal can be improved by converting the optical signal into the initial electric signal, the influence of the external environment on the digital signal is reduced, and the stability of the generation of the digital signal is further improved.

In an alternative implementation, the detection module comprises a photodetector PD capable of converting an optical signal into an electrical signal.

In some other embodiments, the detection module may also include other devices capable of sensing optical signals, such as a photoelectric measurement sensor, an avalanche photodiode, and the like.

In a specific implementation, when the differential module is used for converting the initial electrical signal into the first differential signal and the second differential signal, the first differential signal and the second differential signal with different differential conversion ratios can be obtained according to actual requirements.

As an implementation example, the differential conversion ratio of the differential module in the embodiments of the present disclosure may be adjustable, and the differential conversion ratio may be used to characterize the amplification factor of the initial electrical signal.

That is, by adjusting the differential conversion ratio of the differential module, the amplification factor of the initial electrical signal can be controlled, and the initial electrical signal is amplified to different degrees, so that differential signals (including the first differential signal and the second differential signal) with different amplitudes are obtained, and the optical communication receiving unit can be suitable for different scenes.

In some embodiments, differential modules with different structures and characteristics may be used to perform differential transformation processing on the initial electrical signal, so as to obtain a corresponding first differential signal and a corresponding second differential signal.

As an alternative example, the differential module in embodiments of the present disclosure may include at least one Balun (Balun-Unbalance), either Balun including a first coil and a second coil coupled to each other, wherein the first coil is coupled to the detection module; the second coil is coupled to the digital signal generation module.

In connection with the schematic structural diagrams of an optical communication receiving unit shown in fig. 1 and 2, the differential module 122 may include a balun, wherein the balun may include a first coil LP1 and a second coil LP2 coupled to each other, wherein the first coil LP1 may be coupled to the probe module 121, and the second coil LP2 may be coupled to the digital signal generating module 123, and the initial electrical signal generated by the probe module 121 may be converted into a first differential signal and a second differential signal through the first coil LP1 and the second coil LP2 and output to the digital signal generating module 123.

In an alternative implementation, when the differential module is a balun, the differential conversion ratio of the differential module is determined according to the resistance value of the first coil and the resistance value of the second coil in the balun.

Namely, the differential conversion proportion of the differential module can be changed by adjusting the resistance value of the first coil and/or the resistance value of the second coil in the balance-unbalance converter, so that the amplification factor of the initial electric signal can be changed.

With continued reference to fig. 2, by changing the resistance value of the first coil LP1 and/or the resistance value of the second coil LP2, the conversion ratio of the Balun may be changed, and the conversion ratio of the Balun1 may be used as the current differential conversion ratio of the differential module.

In an alternative example, the resistance values of the first coil and the second coil may be changed by changing parameters such as length, thickness, material, etc. of the first coil and the second coil.

From the foregoing, it can be seen that the ratio of the resistance of the first coil and the resistance of the second coil in the balun can be used as the differential transformation ratio of the differential module. Thus, in some embodiments of the present disclosure, the resistance values of the first coil and the second coil may be adjusted such that the balun has different transformation ratios, and thus the balun having the different transformation ratios may be selected as the differential module.

As an implementation example, the optical communication receiving unit in the embodiments of the present disclosure may include a plurality of balun, and the conversion ratio of each balun may be different.

As shown in fig. 3, in another schematic structural diagram of an optical communication receiving unit in the embodiment of the present disclosure, the plurality of baluns may be n baluns, for example, balun11 to Balun1n, where conversion ratios of the Balun11 to Balun1n are different.

For example, the conversion ratios of Balun11 to Balun1n are k1, k2, …, kn, respectively, and k1, k2, …, kn are all different, where n is an integer greater than 1, and the specific structure of each Balun can be seen in fig. 2 and the corresponding description.

It should be noted that the embodiment of the present disclosure is not limited to a specific value of the conversion ratio of the balun, as long as the conversion ratios of the plurality of balun are different. For example, the plurality of balun may have a balun with a transformation ratio of greater than 1, a balun with a transformation ratio of less than 1, or a balun with a transformation ratio of 1.

In some embodiments, the transformation ratio may be a ratio of a resistance of the first coil and a resistance of the second coil in the balun. Therefore, by selecting the first coil and the second coil with different resistance values, each balance-unbalance converter has different conversion ratios, and further by selecting different balance-unbalance converters, the differential module has different differential conversion ratios, and parameters of the balance-unbalance converters do not need to be adjusted.

In a specific implementation, a plurality of baluns may be disposed on the substrate, and the initial electrical signal may be amplified by a corresponding multiple by using different baluns.

In some embodiments of the present disclosure, baluns having different conversion ratios may be coupled between the detection module and the digital signal generation module in a variety of ways.

As an alternative example, the differential module in the embodiments of the present disclosure may further include a plurality of gating channels, one gating channel corresponding to each balun, and the gating channel being coupled between the corresponding balun and the detection module; the gating channel is configured to conduct a path between the corresponding balun and the detection module when gated; the conversion ratio of the balance-unbalance converter in the conducting state is the current differential conversion ratio of the differential module.

With continued reference to fig. 3, the differential module may also include n strobe channels, such as strobe channels XT1 through XTn, corresponding to the n Balun, where, the strobe channel XT1 is coupled between the Balun11 and the detection module 121 the strobe channel XT2 is coupled between the Balun12 and the detection module 121 … …, the strobe channel XTn is coupled between the Balun1n and the detection module 121.

When any one of the strobe channels XT1 to XTn is strobed, the path between the balun and the detection module corresponding to the strobed strobe channel is turned on. For example, when the strobe channel XT1 is strobed, the path between the Balun1 and the detection module 121 is turned on, and at this time, the conversion ratio k1 of the Balun1 may be used as the current differential conversion ratio of the differential module, and thus the initial electrical signal may be amplified by k1 times, and the amplified first differential signal and second differential signal may be output to the digital signal generating module.

In some embodiments, the conversion ratio of each balun may be preconfigured, and then the corresponding gating channels may be gated according to actual requirements and different scenes, so as to amplify the initial electrical signal to a corresponding degree. For example, in the case of a lower digital signal strength, a balun with a larger conversion ratio may be selected to increase the digital signal strength.

In implementations, any of the gating channels may be gated in a variety of ways. For example, the auxiliary device may respond to the input strobe signal to strobe any one of the strobe channels, automatically strobe according to the determination condition, manually strobe, or by using the auxiliary device electrically connected to the strobe channels.

That is, an asymmetric balun is used to convert the initial electrical signal into a first differential signal and a second differential signal.

In a specific implementation, the differential signal may be a differential current signal and a differential voltage signal, and the embodiments of the present disclosure do not impose any limitation on the type of differential signal.

In some examples, the differential signal may be a differential current signal.

By adopting the differential module in the example, the initial electric signal can be converted into the first differential signal and the second differential signal, and the first differential signal and the second differential signal with different amplitudes can be obtained by adjusting the differential conversion proportion of the differential module, so that the digital signal generating module can generate the digital signal corresponding to the first differential signal and the second differential signal according to the first differential signal and the second differential signal.

In some embodiments of the present disclosure, a digital signal generating module 123 includes a gain submodule (not shown) and a comparison submodule 1231 in accordance with one of the embodiments of the present disclosure described in connection with fig. 1 and 4, wherein:

the gain submodule is coupled with the differential module 122, the comparison submodule 1231 and the power supply VDD respectively, and is configured to amplify the first differential signal and the second differential signal, and convert the types of the first differential signal and the second differential signal to obtain a first differential voltage and a second differential voltage;

The comparing sub-module 1231 is configured to output a corresponding digital signal according to the first differential voltage and the second differential voltage.

In an alternative implementation, the gain sub-module can amplify and type-convert the first differential signal and the second differential signal respectively, input the obtained first differential voltage to the first input end of the comparison sub-module, and input the obtained second differential voltage to the second input end of the comparison sub-module, so that corresponding digital signals can be output according to the relative magnitude relation between the first differential voltage and the second differential voltage.

In some embodiments, the first input of the comparison sub-module may be a positive input (+) and the second input of the comparison sub-module may be an negative input (-).

The gain of the digital signal can be improved by amplifying the first differential signal and the second differential signal, and the digital signal corresponding to the optical signal can be obtained by converting the types of the first differential signal and the second differential signal and adapting to the comparison sub-module.

In some embodiments of the present disclosure, the first differential signal and the second differential signal may be processed separately by providing different electronics or circuits at the gain sub-module.

As an implementation example, with continued reference to fig. 4, the gain sub-module may include a first gain device 1232 and a second gain device 1233, where:

The first gain device 1232, coupled to the differential module 122, the first input terminal of the comparing sub-module 1231, and the power supply VDD, is configured to amplify the first differential signal, and convert the type of the first differential signal to obtain the first differential voltage;

The second gain device 1233, coupled to the differential module 122, the second input terminal of the comparing sub-module 1231, and the power supply VDD, is configured to amplify the second differential signal, and convert the type of the second differential signal to obtain the second differential voltage.

In an alternative implementation, the first gain device 1232 may amplify and type-convert the first differential signal and input the obtained first differential voltage to the first input terminal of the comparison submodule 1231, and the second gain device 1233 may amplify and type-convert the second differential signal and input the obtained second differential voltage to the second input terminal of the comparison submodule 1231.

That is, the first differential signal and the second differential signal are amplified and subjected to type conversion respectively through different gain devices, so that the probability of crosstalk between the first differential signal and the second differential signal can be reduced, the anti-interference performance in the signal transmission process can be improved, and the processing efficiency can be improved.

In some embodiments of the present disclosure, with continued reference to fig. 4, the first gain device 1232 may include: a first resistor R1 and a second resistor R2, where a first end of the first resistor R1 is grounded, and a second end of the first resistor R1 is coupled to a first end of the second resistor R2, a first input end of the comparison sub-module 1231, and a first output end of the differential module 122, respectively; the second end of the second resistor R2 is coupled to the power supply VDD.

The second gain device 1233 includes: a third resistor R3 and a fourth resistor R4, wherein a first end of the third resistor R3 is coupled to the power supply VDD, and a second end of the third resistor R3 is coupled to the first end of the fourth resistor R4, the second input end of the comparing sub-module 1231, and the second output end of the differential module 122, respectively; the second end of the fourth resistor R4 is grounded.

Referring to fig. 4 and 5, fig. 5 shows a waveform of an initial electrical signal I converted by the detection module within 0 to 50 μs, a waveform of a first differential voltage signal U ₁ corresponding to a first differential signal converted by the first gain device 1232, and a waveform of a second differential voltage signal U ₂ corresponding to a second differential signal converted by the second gain device 1233.

As shown in fig. 5, in a period of 0 to t ₂, a waveform change schematic of an initial electrical signal I over a period of time is shown, where the initial electrical signal I may include a high level segment and a low level segment, and where:

In the period from 0 to t ₁, the initial electrical signal I is in the high level segment, which corresponds to a signal amplitude I _L1. When an initial electric signal I with a signal amplitude of I _L1 is converted into a first differential signal and a second differential signal, and is input into a gain submodule, a first differential voltage U _L11 corresponding to the first differential signal can be obtained through a first gain device 1232; the second gain device 1233 can obtain a second differential voltage U _L22 corresponding to the second differential signal.

At time t ₁, the initial electrical signal I transitions from a high level to a low level.

In the period from t ₁ to t ₂, the initial electrical signal I is in the low level segment, which corresponds to a signal amplitude I _L2. When an initial electric signal I with a signal amplitude of I _L2 is converted into a first differential signal and a second differential signal, and is input into a gain submodule, a first differential voltage U _L12 corresponding to the first differential signal can be obtained through a first gain device 1232; the second gain device 1233 can obtain a second differential voltage U _L21 corresponding to the second differential signal.

The first differential signal and the second differential signal are differential signals, so that the voltage signals obtained by converting the first differential signal and the second differential signal are voltage differential signals with equal amplitude and 180-degree phase difference, and the voltages corresponding to the voltage signals are differential voltages.

Referring next to fig. 5, regardless of the time period from 0 to t ₁ or the time period from t ₁ to t ₂, the value of the first differential voltage corresponding to the first differential signal and the value of the second differential voltage corresponding to the second differential signal are different, so that when the first differential voltage corresponding to the first differential signal and the second differential voltage corresponding to the second differential signal are input to the comparison sub-module 1231, a differential mode voltage can be generated between the first input terminal and the second input terminal of the comparison sub-module 1231, for example, the differential mode voltage may be: u _L21-U_L12 is either: u _L11-U_L22, and further under the action of the differential mode voltage, the comparison submodule 1231 may generate a digital signal.

It should be noted that, first, fig. 5 is only for illustrating that, by the gain submodule, the first differential signal can be converted into the first differential voltage and the second differential signal can be converted into the second differential voltage, and the initial electrical signal, the amplitude, the pulse width, and the pulse number of the first differential voltage and the second differential voltage illustrated in fig. 5 are only illustrative, and for different optical communication receiving scenarios, different waveform diagrams can be obtained, which is not limited by the embodiment of the present disclosure; next, fig. 5 is an illustration of taking an initial electrical signal as a current signal, and in some other embodiments, the initial electrical signal may be a voltage signal.

With continued reference to fig. 4, when the first gain device 1232 does not acquire the first differential signal, since the first resistor R1 and the second resistor R2 are connected in series, and the second resistor R2 is coupled to the power supply VDD, the voltage value of the first input terminal of the comparing sub-module 1231 may be: u _VDD*R_R1/(R_R1+R_R2), wherein U _VDD is a voltage provided by the power supply VDD, R _R1 is a resistance of the first resistor R1, and R _R2 is a resistance of the second resistor R2.

When the second gain device 1233 does not obtain the second differential signal, since the third resistor R3 and the fourth resistor R4 are connected in series, and the third resistor R3 is coupled to the power supply terminal VDD, the voltage value of the first input terminal of the comparing sub-module 1231 may be: u _VDD*R_R4/(R_R3+R_R4), wherein U _VDD is a voltage provided by the power supply VDD, R _R3 is a resistance of the third resistor R3, and R _R4 is a resistance of the fourth resistor R4.

Further, by the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4, a suitable static operating voltage can be provided to the first input terminal and the second input terminal of the comparing sub-module 1231, for example, the static operating voltage of the first input terminal (the in-phase input terminal) may be U _VDD*R_R1/(R_R1+R_R2, and the static operating voltage of the second input terminal (the opposite-phase input terminal) may be U _VDD*R_R4/(R_R3+R_R4.

In the embodiment of the disclosure, parameters of the first resistor, the second resistor, the third resistor and the fourth resistor can be flexibly set according to the actual working state of the optical communication receiving unit.

As an alternative example, there are at least two resistances different from each other among the first resistance, the second resistance, the third resistance, and the fourth resistance.

Specifically, since the first resistor, the second resistor, the third resistor and the fourth resistor may have different resistance values of at least two resistors, the first differential voltage obtained through amplification and type conversion of the first resistor is different from the second differential voltage obtained through amplification and type conversion of the second resistor, and thus the differential mode voltage generated between the first input end and the second input end of the comparison sub-module exceeds the voltage threshold value of the comparison sub-module.

As an alternative example, the resistance of the first resistor may be the same as the resistance of the third resistor, and the resistance of the second resistor may be the same as the resistance of the fourth resistor, so that the first gain device and the second gain device may have the same amplification factor.

As yet another alternative example, the resistance value of at least one of the first resistor, the second resistor, the third resistor, and the fourth resistor is adjustable. By adjusting the resistance value of at least one of the first resistor, the second resistor, the third resistor and the fourth resistor, the amplitude of the differential mode voltage generated between the first input end and the second input end of the comparison sub-module and the bandwidth of the generated digital signal can be adjusted, so that the optical communication receiving unit has higher communication frequency.

In some embodiments, by adjusting the resistance of at least one of the first resistor, the second resistor, the third resistor and the fourth resistor, the bandwidth of the generated digital signal may be 10Mbps to 300Mbps, and the communication frequency of the optical communication receiving unit may reach 1MHz to 1GHz.

In some embodiments of the present disclosure, when the comparing sub-module obtains the first differential voltage and the second differential voltage, a corresponding digital signal may be output according to a relative magnitude relation of the first differential voltage and the second differential voltage.

For example, the comparison sub-module may output a first digital signal when the first differential voltage is greater than the second differential voltage, and output a second digital signal when the first differential voltage is less than the second differential voltage.

As a specific example, as shown in fig. 5, a waveform diagram of the digital signal U _o generated by the comparison sub-module within 0 to 50 μs is shown. In the period from 0 to t ₁, the first differential voltage U ₁ is greater than the second differential voltage U ₂, and the comparing submodule may output a first digital signal with an amplitude of U _o1; in the period from t ₁ to t ₂, the first differential voltage U ₁ is smaller than the second differential voltage U ₂, and the comparing sub-module may output the second digital signal with the amplitude of U _o2.

It should be noted that, the amplitude, pulse width, pulse number, and transition time of the high and low levels of the digital signal illustrated in fig. 5 are only illustrative, and different waveform diagrams may be obtained for different optical communication receiving scenarios, which is not limited in the present disclosure.

In specific implementation, according to actual application scenes and requirements, the laser radar in the embodiment of the disclosure can be further expanded to further improve the stability of digital signal generation.

As an alternative example, as shown in fig. 6, the optical communication receiving unit 120 in the embodiment of the disclosure may further include: a dc source module 124, the dc source module 124 may be coupled to the detection module 121 and configured to provide a dc bias voltage to the detection module 121.

In an alternative implementation, the dc source module 124 may provide a dc source electrical signal to the detection module 121, so that the detection module 121 can detect an optical pulse signal emitted by the light source and convert the optical pulse signal into an initial electrical signal.

In some embodiments of the present disclosure, as shown in the schematic structure of the optical communication receiving unit in fig. 7, the dc source module 124 may include a dc power source VCC and a fifth resistor R5, where a first end of the fifth resistor R5 may be connected to the dc power source VCC, and a second end of the fifth resistor R5 may be coupled to the detection module 121.

As another alternative example, as shown in fig. 6, the optical communication receiving unit 120 in the embodiment of the present disclosure may further include: the first filtering module 125 may be coupled to the dc source module 124, the detecting module 121, and the differential module 122, respectively, and configured to filter noise in the dc bias voltage, so as to further improve stability and signal-to-noise ratio of digital signal generation.

In some embodiments of the present disclosure, as shown in fig. 7, the first filtering module 125 may include a capacitor C1, where a first end of the capacitor C1 may be coupled to the dc source module 124 and the detection module 121, respectively, and a second end of the capacitor C1 may be coupled to the differential module 122 and the ground, respectively.

It should be noted that the first filtering module may also be other components capable of filtering noise, for example, the first filtering module may include a device composed of at least two elements of capacitance, resistance or inductance, which is not limited in any way by the embodiments of the present disclosure.

As yet another alternative example, as shown in fig. 6, the optical communication receiving unit 120 in the embodiment of the present disclosure may further include: the second filtering module 126 may be disposed between the differential module 122 and the digital signal generating module 123, and configured to filter noise in the first differential signal and the second differential signal, so as to further improve stability and signal-to-noise ratio of digital signal generation.

In some embodiments of the present disclosure, as shown in fig. 7, the second filtering module 126 may include a common mode inductance, wherein the common mode inductance may include: the first common mode coil LA and the second common mode coil LB are coupled to the differential module 122, and the second ends of the first common mode coil LA and the second common mode coil LB are coupled to the digital signal generating module 123.

And the common-mode inductor is adopted as the second filtering module, so that electromagnetic interference (EMI) signals generated when a circuit in the optical communication receiving unit works can be reduced, common-mode noise is restrained, the EMI interference intensity can be effectively reduced, and the communication quality is improved.

It should be noted that while the above describes a number of embodiments provided by the present disclosure, various alternatives presented by the various embodiments may be combined, cross-referenced, with each other without conflict, extending beyond what is possible, all of which are considered embodiments of the disclosure.

In order to better understand and implement the specific working principle of the optical communication receiving unit provided in the present disclosure, the following is detailed by specific examples with reference to the accompanying drawings.

With continued reference to fig. 7, the dc source module 124 may include a dc source VCC and a fifth resistor R5; the first filtering module 125 may include a capacitor C1; the detection module 121 may include a photodetector PD; the differential module 122 may include a balun; the second filtering module 126 may include a common mode inductance; the digital signal generating module may include a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, and a comparator TC, where the connection relationship inside the optical communication receiving unit is:

The first end of the fifth resistor R5 is connected with the direct current source VCC, and the second end of the fifth resistor is respectively connected with the first end of the photoelectric detector PD and the first end of the capacitor C1; the second end of the capacitor C1 is respectively connected with the first end of the first coil LP1 and the ground; a second end of the photodetector PD is connected to a second end of the first coil LP 1.

The first end of the second winding LP2 is connected to the first end of the first common-mode winding LA, and the second end of the second winding LP2 is connected to the first end of the second common-mode winding LB.

The second end of the first common mode coil LA is respectively connected with the second end of the first resistor R1, the first end of the second resistor R2 and the first input end of the comparator TC; the first end of the first resistor R1 is grounded; the second end of the second resistor R2 is connected to the power supply VDD.

The second end of the second common-mode coil LB is respectively connected with the second end of the third resistor R3, the first end of the fourth resistor R4 and the second input end of the comparator TC; the first end of the third resistor R3 is connected with a power supply VDD; the second terminal of the fourth resistor R4 is grounded.

The working principle of the optical communication receiving unit is as follows:

The direct current source VCC, the fifth resistor R5 and the capacitor C1 provide a stable direct current bias voltage for the photo detector PD, and the photo detector PD can convert the detected optical signal into an initial electrical signal. By the interaction of the first winding LP1 and the second winding LP2 in the balun, the initial electrical signal can be converted into a first differential signal and a second differential signal having the same amplitude and 180 ° out of phase.

The common-mode inductor can filter common-mode noise in the first differential signal and the second differential signal, so that electromagnetic interference is reduced, and the first resistor R1 can amplify the first differential signal, convert the first differential signal into a first differential voltage and output the first differential voltage to the first input end of the comparator TC; the fourth resistor R4 may amplify the second differential signal, convert the second differential signal into a second differential voltage, and output the second differential voltage to the second input end of the comparator TC, where the comparator TC may generate a corresponding digital signal according to the first differential voltage and the second differential voltage, so as to complete the receiving process of the optical signal in optical communication.

It will be appreciated that the configuration shown in fig. 7 described above is merely exemplary. In particular implementations, the above-described circuitry may be modified or selected. For example, the differential module 122 may be the structure shown in fig. 3; for another example, the photodetector PD is replaced with an avalanche photodiode or the like. Based on this, different extension schemes can be obtained, and the embodiments of the present disclosure are not limited to these extension schemes.

By adopting the optical communication receiving unit described in the above embodiment, the optical signal sent by the light source can be converted into the digital signal, and the digital signal can be used for representing the information carried by the optical signal, so that the information carried in the optical signal can be obtained by processing the digital signal.

In some embodiments of the present disclosure, the lidar may further include a data processing unit, which may be coupled to the optical communication receiving unit, and configured to process the digital signal to obtain information carried in the optical signal.

For example, by processing the digital signal, a control signal, point cloud data, and the like can be acquired.

In some embodiments, the data processing unit may be implemented by a central processing unit (Central Processing Unit, CPU), field programmable gate array (Field Programmable GATE ARRAY, FPGA), or the like, processing chip, or may be implemented by an Application Specific Integrated Circuit (ASIC) or one or more integrated circuits configured to implement embodiments of the present disclosure.

It is noted that references to "one embodiment" or "an embodiment" of the present disclosure refer to a particular feature, structure, or characteristic that may be included in at least one implementation of the present disclosure. And in the description of this disclosure, the terms "first," "second," "third," "fourth," and the like are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining a term "first," "second," "third," "fourth," etc. may explicitly or implicitly include one or more such feature. Moreover, the terms "first," "second," "third," "fourth," and the like are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the disclosure described herein are capable of operation in other sequences than illustrated or otherwise described herein.

Although the embodiments of the present disclosure are disclosed above, the present utility model is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the utility model, and the scope of the utility model should be assessed accordingly to that of the appended claims.

Claims

1. A lidar, comprising:

A light source configured to emit an optical signal;

2. The lidar according to claim 1, wherein the optical communication receiving unit comprises:

3. The lidar of claim 2, wherein a differential transformation ratio of the differential module is adjustable, the differential transformation ratio being used to characterize a magnification of the initial electrical signal.

4. The lidar of claim 3, wherein the difference module comprises:

At least one balun, any balun comprising a first coil and a second coil coupled to each other, wherein the first coil is coupled to the detection module; the second coil is coupled to the digital signal generation module.

5. The lidar of claim 4, wherein the differential conversion ratio of the differential module is determined based on a resistance of a first coil and a resistance of a second coil in the balun.

6. The lidar of claim 4, wherein the at least one balun is a plurality of baluns, and the transformation ratio of each balun is different, the transformation ratio being a ratio of a resistance of a first coil and a resistance of a second coil in the balun.

7. The lidar of claim 6, wherein the difference module further comprises a plurality of gating channels, one gating channel corresponding to each balun, and wherein a gating channel is coupled between the corresponding balun and the detection module; the gating channel is configured to conduct a path between the corresponding balun and the detection module when gated; the conversion ratio of the balance-unbalance converter in the conducting state is the current differential conversion ratio of the differential module.

8. The lidar of claim 2, wherein the digital signal generation module comprises a gain sub-module and a comparison sub-module, wherein:

9. The lidar of claim 8, wherein the gain sub-module comprises a first gain device and a second gain device, wherein:

10. The lidar of claim 9, wherein the first gain device comprises: the first end of the first resistor is grounded, and the second end of the first resistor is respectively coupled with the first end of the second resistor, the first input end of the comparison sub-module and the first output end of the differential module; a second end of the second resistor is coupled with the power supply;

11. The lidar of claim 10, wherein at least two of the first resistor, the second resistor, the third resistor, and the fourth resistor have different resistance values.

12. The lidar of claim 10, wherein the first resistor has a resistance that is the same as a resistance of the third resistor, and wherein the second resistor has a resistance that is the same as a resistance of the fourth resistor.

13. The lidar according to any of claims 10 to 12, wherein a resistance value of at least one of the first resistor, the second resistor, the third resistor, and the fourth resistor is adjustable.

14. The lidar of claim 8, wherein the comparison sub-module is configured to output a first digital signal when the first differential voltage is greater than the second differential voltage; and outputting a second digital signal when the first differential voltage is smaller than the second differential voltage.

15. The lidar of claim 2, wherein the detection module comprises a photodetector.

16. The lidar according to claim 2, wherein the optical communication receiving unit further comprises:

And the direct current source module is coupled with the detection module and is configured to provide direct current bias voltage for the detection module.

17. The lidar of claim 16, wherein the optical communication reception unit further comprises:

And the first filtering module is coupled with the direct current source module, the detection module and the differential module respectively and is configured to filter noise in the direct current bias voltage.

18. The lidar according to claim 2, wherein the optical communication receiving unit further comprises:

the second filtering module is arranged between the differential module and the digital signal generating module and is configured to filter noise in the first differential signal and the second differential signal.

19. The lidar of claim 18, wherein the second filtering module comprises a common mode inductance.

20. The lidar of claim 1, further comprising:

And the data processing unit is coupled with the optical communication receiving unit and is configured to process the digital signal so as to obtain information carried in the optical signal.