Laser radar system and vehicle

Abstract

The present invention discloses a laser radar system and a vehicle. The laser radar system includes: a laser emission module, the laser emission module includes a pulse sequence generation unit and a laser generation unit; the pulse sequence generation unit includes a pulse signal generation subunit and an operation subunit; the operation subunit is used to obtain a pulse sequence; the laser generation unit is used to emit an outgoing laser signal, and the outgoing laser signal includes outgoing laser coding information; a laser receiving module, the laser receiving module includes a photoelectric detection unit and an analysis unit, the photoelectric detection unit is used to receive and convert the reflected laser signal into an electrical signal; the reflected laser signal includes reflected laser coding information; the analysis unit is used to receive the electrical signal, and when the reflected laser coding information is obtained to be the same as the outgoing laser coding information, it is determined that the reflected laser signal is emitted by the laser emission module. The laser radar system provided by the embodiment of the present invention can avoid interference from laser signals of other laser radar systems.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of automotive radar technology, and in particular to a laser radar system and a vehicle. Background Art

[0002] At present, LiDAR is increasingly used in fields such as autonomous driving, and has become a hot topic of concern. However, with the increase in the number of vehicles using LiDAR, the mutual interference problem between LiDAR systems on different vehicles is becoming more and more serious.

[0003] If the wavelength of the laser signal emitted by the laser radar systems of other vehicles around the vehicle is the same as the wavelength of the laser signal emitted by the laser radar system of the vehicle, the laser radar system of the vehicle will find it difficult to distinguish which vehicle the laser signal comes from. For example, on the same road, if there are multiple vehicles with the same laser radar system emission wavelength, when these vehicles are close to each other, each laser radar system may receive the laser signal emitted by the laser radar system of other vehicles and determine it as a target echo, which will cause the radar to be interfered and produce erroneous detection results.

[0004] To solve the above problems, existing LiDAR systems generally reduce the radar field of view angle and the photosensitive array area to avoid interference. However, this measure is almost ineffective for laser signals emitted by LiDAR systems with the same wavelength. Summary of the invention

[0005] The present invention provides a laser radar system and a vehicle, which can avoid interference from laser signals of other laser radar systems.

[0006] In a first aspect, an embodiment of the present invention provides a laser radar system, including:

[0007] A laser emission module, the laser emission module comprising a pulse sequence generating unit and a laser generating unit electrically connected to each other; wherein the pulse sequence generating unit comprises a pulse signal generating subunit and an operation subunit electrically connected to each other; the pulse signal generating subunit is used to generate at least two pulse signals, and the operation subunit is used to operate at least two of the pulse signals to obtain a pulse sequence; the pulse sequence comprises at least two sub-pulses; the laser generating unit is used to receive the pulse sequence and generate and emit an outgoing laser signal according to the pulse sequence, and the outgoing laser signal comprises outgoing laser coding information;

[0008] A laser receiving module, the laser receiving module includes a photoelectric detection unit and an analysis unit electrically connected to each other, the photoelectric detection unit is used to receive a reflected laser signal reflected by a target object and convert the reflected laser signal into an electrical signal; the reflected laser signal includes reflected laser coding information; the analysis unit is used to receive the electrical signal and, when the reflected laser coding information is obtained based on the electrical signal analysis and is identical to the emitted laser coding information, determine that the reflected laser signal is emitted by the laser emitting module.

[0009] Furthermore, the laser emission module also includes a radio frequency amplifier;

[0010] The radio frequency amplifier is connected to the pulse sequence generating unit and the laser generating unit respectively, and is used for amplifying the pulse sequence and sending the amplified pulse sequence to the laser generating unit.

[0011] Furthermore, the pulse width of the pulse signal is in nanoseconds, and the pulse width of the sub-pulse is in picoseconds.

[0012] Further, the laser generating unit includes a seed source laser, a pump laser, a first beam combiner, a first gain fiber and a collimator;

[0013] The seed source laser is used to generate seed laser, and the pump laser is used to generate pump laser;

[0014] The first beam combiner is used to combine the seed laser and the pump laser to obtain a first combined laser beam, and send the first combined laser beam to the first gain optical fiber;

[0015] The first gain optical fiber is used to gain the first combined laser beam and then send it to the collimator;

[0016] The collimator is used to collimate the first combined laser beam and then emit it.

[0017] Furthermore, the laser generating unit further comprises a beam splitter, a second beam combiner and a second gain optical fiber;

[0018] The beam splitter is used to split the pump laser into at least two sub-pump laser beams; wherein the at least two sub-pump laser beams include a first pump laser and a second pump laser;

[0019] The first beam combiner is used to combine the seed laser and the first pump laser to obtain a second combined laser beam, and send the second combined laser beam to the first gain optical fiber;

[0020] The first gain optical fiber is used to gain the second combined laser beam and then send it to the second combiner;

[0021] The second beam combiner is used to combine the second combined laser beam and the second pump laser beam to obtain a third combined laser beam, and then send the third combined laser beam to the second gain optical fiber;

[0022] The second gain optical fiber is used to gain the third combined laser beam and then send it to the collimator;

[0023] The collimator is used to collimate the third combined laser beam and then emit it.

[0024] Further, the laser generating unit further includes a first isolator, a second isolator, a third isolator and a filter;

[0025] The first isolator is located between the seed source laser and the first beam combiner;

[0026] The second isolator is located between the first gain fiber and the second combiner;

[0027] The third isolator is located between the second beam combiner and the collimator;

[0028] The first isolator, the second isolator and the third isolator are all used to control the propagation direction of the light beam;

[0029] The filter is located between the first gain optical fiber and the second isolator, and is used for transmitting a light beam with a preset wavelength.

[0030] Further, the photoelectric detection unit includes a receiving lens and a photoelectric detector;

[0031] The receiving lens is used to receive the reflected laser signal reflected by the target object and transmit the reflected laser signal to the photoelectric detector;

[0032] The photodetector is used to convert the reflected laser signal into the electrical signal.

[0033] Further, the pulse sequence generating unit comprises a field programmable gate array;

[0034] The pulse sequence generating unit is multiplexed as the analyzing unit.

[0035] Furthermore, the laser receiving module also includes an amplifier and an analog-to-digital converter;

[0036] The amplifier is connected to the photodetector and the analog-to-digital converter respectively, and the analog-to-digital converter is also connected to the analysis unit;

[0037] The amplifier is used to receive and amplify the electrical signal;

[0038] The analog-to-digital converter is used to convert the amplified electrical signal into a digital signal.

[0039] In a second aspect, an embodiment of the present invention further provides a vehicle, comprising a laser radar system as described in any one of the first aspects above.

[0040] The laser radar system provided by an embodiment of the present invention includes a laser emitting module and a laser receiving module; the laser emitting module includes a pulse signal generating subunit, an operation subunit and a laser generating unit, the pulse signal generating subunit and the operation subunit can form a pulse sequence, and the pulse sequence can control the laser generating unit to generate an outgoing laser signal with outgoing laser coding information; the laser receiving module includes a photoelectric detection unit and an analysis unit, the photoelectric detection unit can receive a reflected laser signal and generate an electrical signal, the analysis unit can identify the reflected laser coding information in the electrical signal, and compare whether the reflected laser coding information is the same as the outgoing laser coding information, and then it can be determined whether the received reflected laser light beam is emitted by the laser emitting module of the laser radar system, so as to avoid interference from laser signals of other laser radar systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a schematic structural diagram of a laser radar system provided by an embodiment of the present invention;

[0042] Figure 2 is a schematic diagram of a laser emission module provided in an embodiment of the present invention forming an outgoing laser signal;

[0043] Figure 3 is a schematic diagram of the structure of an outgoing laser signal and a reflected laser signal provided by an embodiment of the present invention;

[0044] Figure 4 is a schematic structural diagram of another laser radar system provided by an embodiment of the present invention;

[0045] Figure 5 is a schematic structural diagram of a laser generating unit provided in an embodiment of the present invention;

[0046] Figure 6 It is a schematic structural diagram of another laser generating unit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0048] Figure 1It is a schematic diagram of the structure of a laser radar system provided in an embodiment of the present invention. Specifically, the laser radar system includes: a laser emitting module 10, the laser emitting module 10 includes a pulse sequence generating unit 11 and a laser generating unit 12 electrically connected to each other; wherein the pulse sequence generating unit 11 includes a pulse signal generating subunit 111 and an operation subunit 112 electrically connected to each other; the pulse signal generating subunit 111 is used to generate at least two pulse signals, and the operation subunit 112 is used to operate at least two pulse signals to obtain a pulse sequence; the pulse sequence includes at least two sub-pulses; the laser generating unit 12 is used to receive the pulse sequence and generate and emit an outgoing laser signal according to the pulse sequence, and the outgoing laser signal includes outgoing laser coding information; a laser receiving module 20, the laser receiving module 20 includes a photoelectric detection unit 21 and an analysis unit 22 electrically connected to each other, the photoelectric detection unit 21 is used to receive a reflected laser signal reflected by a target object and convert the reflected laser signal into an electrical signal; the reflected laser signal includes reflected laser coding information; the analysis unit 22 is used to receive the electrical signal, and when the reflected laser coding information obtained according to the electrical signal analysis is the same as the outgoing laser coding information, it is determined that the reflected laser signal is emitted by the laser emitting module 10.

[0049] Specifically, the laser emitting module 10 can emit an outgoing laser signal, which will return when encountering an obstacle, and the laser receiving module 20 can receive the reflected laser signal. For the convenience of description, the laser signal emitted by the laser emitting module 10 and not reaching the obstacle is called the outgoing laser signal, and the laser signal reflected back by the obstacle is called the reflected laser signal.

[0050] The operation subunit 112 can operate on the signal. Therefore, by using the operation function of the operation subunit 112, the two pulse signals generated by the pulse signal generation subunit 111 can be subjected to a difference operation, thereby forming a pulse sequence. The pulse sequence includes a plurality of sub-pulses, each of which has a width much smaller than the width of the pulse sequence, and the arrangement of the plurality of sub-pulses corresponds to certain characteristic information. Since the number of sub-pulses in the pulse sequence and the positional relationship between them can have a variety of situations, the pulse sequence can include a variety of different characteristic information. After reaching the laser generation unit 12, the pulse sequence containing different characteristic information can stimulate the generation of an outgoing laser signal with different outgoing laser coding information. It can be understood that the outgoing laser coding information corresponds to the characteristic information of the pulse sequence.

[0051] The photoelectric detection unit 21 can receive the reflected laser signal and convert the reflected laser signal into an electrical signal, and the analysis unit 22 can analyze the reflected laser coding information contained in the electrical signal. Since the analysis unit 22 is connected to the pulse sequence generation unit 11, the analysis unit 22 can also obtain the emitted laser coding information through the pulse sequence generation unit 11.

[0052] Because the characteristic coding information contained in the laser usually does not change before and after the laser is reflected. The outgoing laser signal can form a reflected laser signal after being reflected by an obstacle, and the reflected laser coding information in the reflected laser signal is the same as the outgoing laser coding information in the outgoing laser signal. Therefore, it can be determined whether the reflected laser signal is emitted by the laser emitting module 10 in the current laser radar system based on the reflected laser coding information. Specifically, when the reflected laser coding information and the outgoing laser coding information are the same, the analysis unit 22 can determine that the reflected laser signal detected by the photoelectric detection unit 21 is emitted by the laser emitting module 10 in the current laser radar system. Similarly, when the reflected laser coding information and the outgoing laser coding information are different, the analysis unit 11 can determine that the reflected laser signal detected by the photoelectric detection unit 21 is not emitted by the laser emitting module 10 in the current laser radar system.

[0053] It should be noted that, considering the generation cost, the pulse width of the pulse signal generated by the pulse signal generation subunit 111 is relatively large, which makes it difficult for the pulse signal to directly form coded information. Therefore, by performing a difference operation on the two pulse signals through the operation subunit 112, a pulse sequence including multiple sub-pulses can often be obtained, and the pulse width of each sub-pulse is much smaller than the pulse width of the pulse signal, thereby forming the emitted laser coded information at a lower cost. In addition, in order to form a pulse sequence, the two pulse signals generated by the pulse signal generation subunit 111 can have a certain timing difference.

[0054] It should be noted that the number of sub-pulses in a pulse sequence and the position arrangement relationship can have a variety of relationships. The outgoing laser coding information in the outgoing laser signal generated by the same laser radar system at different times, or by different laser radar systems at the same time, is often different. Therefore, when there are multiple laser radar systems provided in this embodiment working in a certain area, the pulse sequence generation unit 11 can control the laser generation unit 12 to emit an outgoing laser signal with outgoing laser coding information, and the analysis module 22 can identify the reflected laser signal corresponding to the outgoing laser coding information, and then each laser radar system can be controlled to only receive the reflected laser signal that matches the outgoing laser coding information. Therefore, multiple laser radar systems can not interfere with each other, thereby ensuring that multiple laser radar systems can work normally at the same time.

[0055] Optionally, the pulse width of the pulse signal is in nanosecond order, and the pulse width of the sub-pulse is in picosecond order.

[0056] Exemplarily, by using the pulse signal generating subunit 111, two pulse sequences with a pulse width of 10ns can be generated; after the two pulse sequences are subjected to difference processing by the operation subunit 112, the pulse width of the sub-pulse formed is 50-100ps. Usually, a pulse sequence formed by two pulse signals with a pulse width of 10ns can include about 10 sub-pulses. Since the pulse width of a picosecond sub-pulse is much smaller than that of a nanosecond pulse, it is easier for a picosecond sub-pulse to form a pulse sequence with coding characteristics. Therefore, in order to obtain the emitted laser coding information, it is necessary to first obtain a pulse sequence including multiple picosecond sub-pulses. However, under normal circumstances, if a picosecond sub-pulse is directly formed, it is difficult and has high requirements on the equipment, thereby increasing the cost of the laser radar system. Compared with picosecond pulses, it is much easier to generate nanosecond pulses, and it is also easier to obtain a picosecond pulse sequence by performing a difference operation on two nanosecond pulse signals using the operation subunit 112. Therefore, by using the subunit 111 capable of generating nanosecond pulse signals to indirectly obtain picosecond pulses, the cost of the laser radar system can be reduced.

[0057] Figure 2 Schematic diagram of the laser emission module provided in the embodiment of the present invention forming an outgoing laser signal. Figure 2 , the pulse signal generating subunit can generate a pulse signal A and a pulse signal B. Exemplarily, the pulse signal A and the pulse signal B are the same, both are square waves, and the pulse width is 10ns. The pulse signal A or the pulse signal B can control the laser generating unit to generate a laser signal a. Exemplarily, the laser signal a can be a Gaussian beam. After the pulse signal A and the pulse signal B are processed by the operation subunit, a sub-pulse C with a pulse width of 100ps can be obtained. After obtaining the first sub-pulse C, the operation subunit can also control the pulse signal A and the pulse signal B to change a certain phase at the same time. For example, the phases of the pulse signal A and the pulse signal B change by 12.5° at the same time; for a square wave with a pulse width of 10ns, the width corresponding to the phase of 12.5° is approximately 350ps. After completing the phase change, the operation sub-unit controls the pulse signal A and the pulse signal B again to generate a 100ps sub-pulse C, then the interval between two adjacent sub-pulses C is approximately 250ps. By changing the phase of the pulse signal A and the pulse signal B multiple times at the same time, multiple sub-pulses C can be obtained, and multiple sub-pulses C can form a pulse sequence.

[0058] Since each sub-pulse C can control the laser generating unit to generate a laser sub-signal b, the outgoing laser signal generated by the laser generating unit controlled by the pulse sequence may include multiple laser sub-signals b. The total width of the pulse sequence may be equal to the width of the pulse signal A or the pulse signal B, and accordingly, the pulse width of the outgoing laser signal may also be equal to the width of the laser signal a. That is, for an outgoing laser signal with a pulse width of 10ns, multiple laser sub-signals b may be included. It can be understood that when the angle adjustment amplitudes of the phases of the pulse signal A and the pulse signal B are different, the intervals between the corresponding two sub-pulses C are also different; two adjacent laser sub-signals b with different intervals correspond to different coding information. By adjusting the variation amplitudes of the pulse signal A and the pulse signal B, an outgoing laser beam with different coding information can be obtained.

[0059] Figure 3 is a schematic diagram of the structure of the outgoing laser signal and the reflected laser signal provided by an embodiment of the present invention. Figure 3 The laser generation unit can generate an outgoing laser signal 1. If the laser signal detected by the photoelectric detection unit is a reflected signal 1, the analysis unit can analyze and obtain the reflected laser coding information corresponding to the reflected signal 1, which is the same as the outgoing laser coding information corresponding to the outgoing laser signal 1, thereby determining that the reflected signal 1 is emitted by the laser emission module. If the signal detected by the photoelectric detection unit is a reflected signal 2, the analysis unit can analyze and obtain that the reflected laser coding information corresponding to the reflected signal 2 is different from the outgoing laser coding information corresponding to the outgoing laser signal 1, thereby determining that the reflected signal 2 is not emitted by the laser emission module.

[0060] Figure 4 is a schematic diagram of the structure of another laser radar system provided by an embodiment of the present invention. Figure 4 The laser emission module also includes a radio frequency amplifier 13; the radio frequency amplifier 13 is connected to the pulse sequence generating unit 11 and the laser generating unit 12 respectively, and is used to amplify the pulse sequence and send the amplified pulse sequence to the laser generating unit 12.

[0061] Generally, the signal strength of the pulse sequence formed after the operation by the operator unit 112 is relatively low. Therefore, the RF amplifier 13 can be used to amplify the pulse sequence to increase the energy of the pulse sequence.

[0062] Optionally, the photoelectric detection unit 21 includes a receiving lens 211 and a photoelectric detector 212; the receiving lens 211 is used to receive the reflected laser signal reflected by the target object and transmit the reflected laser signal to the photoelectric detector 212; the photoelectric detector 212 is used to convert the reflected laser signal into an electrical signal.

[0063] Specifically, the receiving lens 211 can converge the reflected laser signal to converge the reflected laser signal within a larger range, so that the energy of the reflected laser signal is more concentrated. The photodetector 212 can generate a stronger electrical signal based on the converged reflected laser signal. Exemplarily, when the laser radar system provided in this embodiment is used for laser ranging, the reflected laser signal is reflected back by the target object, so the intensity of the reflected laser signal is relatively weak. The focusing effect of the receiving lens 211 on the reflected laser signal can enhance the ranging sensitivity of the laser radar system.

[0064] Optionally, the laser receiving module also includes an amplifier 213 and an analog-to-digital converter 214; the amplifier 213 is connected to the photodetector 212 and the analog-to-digital converter 214 respectively, and the analog-to-digital converter 214 is also connected to the analysis unit 22; the amplifier 213 is used to receive and amplify the electrical signal; the analog-to-digital converter 214 is used to convert the amplified electrical signal into a digital signal.

[0065] Specifically, since the energy of the reflected laser beam is low, the intensity of the electrical signal obtained by the photodetector 212 according to the reflected laser beam is also low, and for the convenience of subsequent processing, it can be amplified by the amplifier 213. In addition, the electrical signal generated by the photodetector 212 is usually an analog signal, and in order to facilitate the analysis unit 22 to process the electrical signal, the analog signal can also be converted into a digital signal by the analog-to-digital converter 214.

[0066] Optionally, the laser generating unit 12 may include a laser diode 121, a laser amplifier 122, and a collimator 123. The laser diode 121 is used to generate a laser beam. However, the energy of the laser beam generated by the laser diode 121 is low, and the laser amplifier 122 can increase the power of the laser beam. Therefore, the laser amplifier 122 can be used to amplify the laser beam. In addition, the collimator 123 can collimate the laser beam to obtain a more collimated emitted laser beam.

[0067] Optionally, the pulse sequence generating unit 111 comprises a field programmable gate array; the pulse sequence generating unit is multiplexed as the analyzing unit 22 .

[0068] Specifically, the field programmable gate array (FPGA) has the advantages of powerful functions, simple operation and excellent performance. When applied to the laser radar system, it can significantly reduce the cost of the laser radar system. In addition, the field programmable gate array can also be reused as the operation subunit 112. In this case, the field programmable gate array can generate two nanosecond pulse signals, and perform a difference operation on the two pulse signals to generate a picosecond pulse sequence, and obtain the outgoing laser coding information according to the pulse sequence. In addition, the field programmable gate array can also obtain the reflected laser coding information based on the electrical signal obtained from the reflected laser signal, and compare whether the outgoing laser coding information and the reflected laser coding information are the same.

[0069] Figure 5 is a schematic diagram of the structure of the laser generating unit provided in an embodiment of the present invention. Figure 5 The laser generating unit includes a seed source laser 201, a pump laser 202, a first beam combiner 203, a first gain fiber 204 and a collimator 123; the seed source laser 201 is used to generate a seed laser, and the pump laser 202 is used to generate a pump laser; the first beam combiner 203 is used to combine the seed laser and the pump laser to obtain a first combined laser, and send the first combined laser to the first gain fiber 204; the first gain fiber 204 is used to gain the first combined laser and then send it to the collimator 123; the collimator 205 is used to collimate the first combined laser and then emit it.

[0070] Specifically, the power of the seed laser generated by the seed source laser 201 is relatively small, usually 10 to 20 mW, which cannot meet the actual demand; the power of the seed laser can be increased by using the pump laser 202. The seed laser and the pump laser can be combined by using the first beam combiner 203 to obtain a first combined laser, and the first gain fiber 204 can amplify the first combined laser to obtain a laser with a relatively large power that can meet the demand. In addition, before the laser beam is emitted from the laser generating unit, the collimator 123 can be used to collimate the laser.

[0071] It should be noted that the seed source laser 201 may include a seed source driving circuit and a seed source optical cavity, and the seed source driving circuit is used to drive the seed source optical cavity to generate a seed laser; the pump laser 202 may include a pump source driving circuit and a pump source optical cavity, and the pump source driving circuit is used to drive the pump source optical cavity to generate a pump laser. It should be noted that the seed source driving circuit is connected to the radio frequency amplifier, and is used to control the seed source optical cavity to generate a seed laser according to a pulse sequence from the video amplifier; at the same time, one end of the pump source driving circuit is also connected to the radio frequency amplifier, and is used to control the pump source optical cavity to generate a pump laser according to a pulse sequence from the video amplifier.

[0072] Figure 6 is a schematic diagram of the structure of another laser generating unit provided by an embodiment of the present invention. Figure 6 The laser generating unit may further include a beam splitter 205, a second beam combiner 206 and a second gain fiber 207; the beam splitter 205 is used to split the pump laser into at least two sub-pump lasers; wherein the at least two sub-pump lasers include a first pump laser and a second pump laser; the first beam combiner 205 is used to combine the seed laser and the first pump laser to obtain a second combined laser, and send the second combined laser to the first gain fiber 204; the first gain fiber 204 is used to gain the second combined laser and then send it to the second beam combiner 206; the second beam combiner 206 is used to combine the second combined laser and the second pump laser to obtain a third combined laser, and then send the third combined laser to the second gain fiber 207; the second gain fiber 207 is used to gain the third combined laser and then send it to the collimator 123; the collimator 123 is used to collimate the third combined laser and then emit it.

[0073] Specifically, in general, the more times the gain is applied, the greater the power of the laser finally obtained. Therefore, in order to obtain a higher power output laser signal, a multi-stage laser gain method can be used to increase the energy of the seed laser. In order to achieve multi-stage gain, the pump laser can be divided into multiple beams using a beam splitter 205, and each pump laser can perform a gain on the seed laser once. The process of multi-stage gain is similar to that of primary gain and will not be described in detail. It should be noted that this embodiment exemplarily provides a laser generation unit that can perform secondary gain, but this should not be understood as a limitation on the number of gain stages.

[0074] Optionally, the laser generating unit further includes a first isolator 218, a second isolator 228, a third isolator 238 and a filter 209; the first isolator 218 is located between the seed source laser 201 and the first combiner 203; the second isolator 228 is located between the first gain fiber 204 and the second combiner 206; the third isolator 238 is located between the second combiner 206 and the collimator 213; the first isolator 218, the second isolator 228 and the third isolator 238 are all used to control the propagation direction of the light beam; the filter 209 is located between the first gain fiber 204 and the second isolator 228, and is used to transmit a light beam of a preset wavelength.

[0075] Specifically, the first isolator 218, the second isolator 228 and the third isolator 238 can all control the propagation direction of the laser beam so that the laser beam propagates in a single direction to prevent the generation of return light. Taking the first isolator 218 as an example, the second combined laser beam formed after the seed laser and the first pump laser are combined has a large energy. Since the laser beam is prone to generate return light at the end face of the first combiner 203 or other optical devices, it not only causes energy waste, but also damages the seed source laser 201 in serious cases. Therefore, using the first isolator 218 to control the propagation direction of the laser can reduce energy loss and avoid the seed source laser 201 from being destroyed. Similarly, the second isolator 228 and the third isolator 238 can also prevent return light and reduce energy loss. After the second combined laser passes through the first gain fiber 204, there are often some components of other wavelengths in the formed laser beam, which belong to stray light, and the filter 209 can selectively transmit lasers of specific wavelengths and prevent stray light of other wavelengths from passing through.

[0076] Based on the same inventive concept, this embodiment further provides a vehicle. The vehicle includes the laser radar system described in any of the above embodiments. For parts not described in detail in this embodiment, please refer to the laser radar system provided in any embodiment.

[0077] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A laser radar system, characterized in that: include: A laser emission module, the laser emission module comprising a pulse sequence generating unit and a laser generating unit electrically connected to each other; wherein the pulse sequence generating unit comprises a pulse signal generating subunit and an operation subunit electrically connected to each other; the pulse signal generating subunit is used to generate at least two pulse signals, and the operation subunit is used to operate at least two of the pulse signals to obtain a pulse sequence; the pulse sequence comprises at least two sub-pulses; the laser generating unit is used to receive the pulse sequence and generate and emit an outgoing laser signal according to the pulse sequence, and the outgoing laser signal comprises outgoing laser coding information; A laser receiving module, the laser receiving module comprising a photoelectric detection unit and an analysis unit electrically connected to each other, the photoelectric detection unit being used to receive a reflected laser signal reflected by a target object and convert the reflected laser signal into an electrical signal; the reflected laser signal comprises reflected laser coding information; the analysis unit is used to receive the electrical signal and, when the reflected laser coding information is obtained according to the electrical signal analysis and is identical to the emitted laser coding information, determine that the reflected laser signal is emitted by the laser emitting module; The operation subunit is used to operate at least two of the pulse signals to obtain a pulse sequence, including: The operation subunit performs a difference operation on at least two pulse signals generated by the pulse signal generating subunit to form a pulse sequence.

2. The laser radar system according to claim 1, characterized in that: The laser emission module also includes a radio frequency amplifier; The radio frequency amplifier is connected to the pulse sequence generating unit and the laser generating unit respectively, and is used for amplifying the pulse sequence and sending the amplified pulse sequence to the laser generating unit.

3. The laser radar system according to claim 1, characterized in that: The pulse width of the pulse signal is in nanosecond order, and the pulse width of the sub-pulse is in picosecond order.

4. The laser radar system according to claim 1, characterized in that: The laser generating unit comprises a seed source laser, a pump laser, a first beam combiner, a first gain optical fiber and a collimator; The seed source laser is used to generate seed laser, and the pump laser is used to generate pump laser; The first beam combiner is used to combine the seed laser and the pump laser to obtain a first combined laser beam, and send the first combined laser beam to the first gain optical fiber; The first gain optical fiber is used to gain the first combined laser beam and then send it to the collimator; The collimator is used to collimate the first combined laser beam and then emit it.

5. The laser radar system according to claim 4, characterized in that: The laser generating unit further comprises a beam splitter, a second beam combiner and a second gain optical fiber; The beam splitter is used to split the pump laser into at least two sub-pump laser beams; wherein the at least two sub-pump laser beams include a first pump laser and a second pump laser; The first beam combiner is used to combine the seed laser and the first pump laser to obtain a second combined laser beam, and send the second combined laser beam to the first gain optical fiber; The first gain optical fiber is used to gain the second combined laser beam and then send it to the second combiner; The second beam combiner is used to combine the second combined laser beam and the second pump laser beam to obtain a third combined laser beam, and then send the third combined laser beam to the second gain optical fiber; The second gain optical fiber is used to gain the third combined laser beam and then send it to the collimator; The collimator is used to collimate the third combined laser beam and then emit it.

6. The laser radar system according to claim 5, characterized in that: The laser generating unit further comprises a first isolator, a second isolator, a third isolator and a filter; The first isolator is located between the seed source laser and the first beam combiner; The second isolator is located between the first gain fiber and the second combiner; The third isolator is located between the second beam combiner and the collimator; The first isolator, the second isolator and the third isolator are all used to control the propagation direction of the light beam; The filter is located between the first gain optical fiber and the second isolator, and is used for transmitting a light beam with a preset wavelength.

7. The laser radar system according to claim 1, characterized in that: The photoelectric detection unit includes a receiving lens and a photoelectric detector; The receiving lens is used to receive the reflected laser signal reflected by the target object and transmit the reflected laser signal to the photoelectric detector; The photodetector is used to convert the reflected laser signal into the electrical signal.

8. The laser radar system according to claim 7, characterized in that: The pulse sequence generating unit comprises a field programmable gate array; The pulse sequence generating unit is multiplexed as the analyzing unit.

9. The laser radar system according to claim 8, characterized in that: The laser receiving module also includes an amplifier and an analog-to-digital converter; The amplifier is connected to the photodetector and the analog-to-digital converter respectively, and the analog-to-digital converter is also connected to the analysis unit; The amplifier is used to receive and amplify the electrical signal; The analog-to-digital converter is used to convert the amplified electrical signal into a digital signal.

10. A vehicle, characterized in that: A laser radar system comprising any one of claims 1-9.

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