WO2019113723A1

WO2019113723A1 - Laser detection method and system

Info

Publication number: WO2019113723A1
Application number: PCT/CN2017/115388
Authority: WO
Inventors: 牟涛涛; 黄晓庆; 骆磊
Original assignee: 深圳前海达闼云端智能科技有限公司
Priority date: 2017-12-11
Filing date: 2017-12-11
Publication date: 2019-06-20
Also published as: CN108124466B; CN108124466A

Abstract

Provided are a laser detection method and system. The laser detection method comprises: within the same detection period, each laser emission unit (11, 21, 31, 411, 421, 431) generates a laser signal and sends a laser signal to a detection object; if the manners in which the plurality of laser emission units (11, 21, 31, 411, 421, 431) generate a laser signal are the same, then the times at which they emit laser signals are different; if the times at which the plurality of laser emission units (11, 21, 31, 411, 421, 431) emit laser signals are the same, then the manners in which they generate laser signals are different; each laser receiving unit (12, 22, 32, 412, 422, 432) receives an echo signal returned by the laser signal via the detection object, and obtains an echo signal matching the laser signal; according to the laser signals emitted by the laser emission units (11, 21, 31, 422, 421, 431) and the echo signals matching the laser signals, processing units (13, 23, 33, 413, 423, 433) determine a target parameter of the detection object. Hence, the laser receiving units (12, 22, 32, 412, 422, 432) accurately identify an echo signal matching a laser signal, enhancing lidar anti-jamming capability and ensuring the accuracy and reliability of obtained target parameters of a detection object.

Description

Laser detection method and system

Technical field

The present disclosure relates to the field of laser radar, and in particular to a laser detection method and system.

Background technique

The current laser radar equipment basically works in the near-infrared band of 905 nm, and its working principle is to transmit a plurality of laser signals to the detector, and then obtain a plurality of echo signals and corresponding laser signals returned according to the received detected objects. Target parameters of the probe, such as distance, azimuth, altitude, speed, attitude, shape, and the like. If the same type of laser radar is installed on an adjacent platform (for example, a vehicle or a flying object) or other nearby platforms, the beam interferes with each other. The laser radar cannot distinguish between the self-beam and the interference beam, that is, different laser radars will Generate signal interference. Moreover, when the laser radar is a multi-line (for example, 16 line, 32 line, 64 line, 128 line, 256 line, etc.) laser radar, each line has a laser emitting unit and a laser receiving unit respectively, so that There is also mutual interference between different lines of the same multi-line lidar. As a result, the target parameters of the obtained probe may be inaccurate, for example, the distance of the obtained probe is inaccurate, and thus there may be a safety hazard. Therefore, enhancing the anti-jamming capability of the laser radar and obtaining reliable target parameters of the probe are extremely important for the application of the laser radar.

Summary of the invention

The present disclosure provides a laser detection method and system to enhance the anti-jamming capability of the laser radar.

In order to achieve the above object, according to a first aspect of an embodiment of the present disclosure, there is provided a laser detecting method applied to a laser detecting system, the laser detecting system including a plurality of laser emitting units, and the plurality of laser emitting units a plurality of corresponding laser receiving units and a plurality of processing units corresponding to the plurality of laser receiving units, the method comprising:

Each of the laser emitting units generates a laser signal and transmits the laser signal to the probe in the same detection period, wherein, in a case where the plurality of laser emitting units generate laser signals in the same manner, The time at which the plurality of laser emitting units emit the laser signals are different from each other, and in a case where the times at which the plurality of laser emitting units emit the laser signals are the same, the manner in which the plurality of laser emitting units generate the laser signals are different from each other;

Each of the laser receiving units receives an echo signal returned by the laser signal via the probe;

Each of the laser receiving units respectively acquires an echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself according to the echo signal received by the laser receiving unit;

The processing unit determines a target parameter of the probe according to a laser signal emitted by each of the laser emitting units and an echo signal matched by the laser signal.

According to a second aspect of an embodiment of the present disclosure, there is provided a laser detecting system including a plurality of laser emitting units, a plurality of laser receiving units in one-to-one correspondence with the plurality of laser emitting units, and a plurality of processing units corresponding to the plurality of laser receiving units, each of the laser emitting units configured to respectively generate a laser signal in the same detection period and transmit the laser signal to the probe, wherein In a case where the laser emitting units generate the laser signals in the same manner, the times at which the plurality of laser emitting units emit the laser signals are different from each other, and in the case where the plurality of laser emitting units emit the laser signals at the same time, the The manner in which a plurality of laser emitting units generate laser signals is different from each other;

Each of the laser receiving units is configured to receive an echo signal returned by the laser signal through the probe, and respectively acquire a laser emitted by a laser emitting unit corresponding to the laser signal according to an echo signal received by itself. The echo signal that the signal matches;

The processing unit is configured to determine a target parameter of the probe according to a laser signal emitted by each of the laser emitting units and an echo signal matched by the laser signal.

According to the above technical solution, when a plurality of laser emitting units generate laser signals in the same detection period, the time at which they emit laser signals is different from each other, and when a plurality of laser emitting units emit laser signals at the same time, they are The manner of generating the laser signals is different from each other, so that each laser receiving unit can accurately recognize the echoes matching the laser signals emitted by the laser emitting units corresponding thereto according to the echo signals received by the respective laser receiving units. The signal enhances the anti-jamming capability of the laser radar, thereby ensuring the accuracy and reliability of the target parameters of the acquired probe.

The above general description and the following detailed description are intended to be illustrative and not restrictive.

DRAWINGS

FIG. 1A is a structural block diagram of a laser detecting system according to an exemplary embodiment.

FIG. 1B is a structural block diagram of a laser detecting system according to another exemplary embodiment.

FIG. 1C is a structural block diagram of a laser detection system according to another exemplary embodiment.

FIG. 2 is a schematic diagram showing a manner in which a plurality of laser emitting units generate laser signals are different from each other according to an exemplary embodiment.

FIG. 3A is a schematic diagram showing a manner in which a plurality of laser emitting units generate laser signals are different from each other according to another exemplary embodiment.

FIG. 3B is a schematic diagram of a laser detection method according to an exemplary embodiment.

FIG. 4 is a schematic diagram showing a time when a plurality of laser emitting units emit laser signals are different from each other according to an exemplary embodiment.

FIG. 5 is a flow chart of a laser detection method according to an exemplary embodiment.

Detailed ways

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. The following description refers to the same or similar elements in the different figures unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with aspects of the present disclosure as detailed in the appended claims.

As shown in FIG. 1A to FIG. 1C, the laser detecting system in the present disclosure may include a plurality of laser emitting units, a plurality of laser receiving units corresponding to the plurality of laser emitting units, and a one-to-one correspondence with the plurality of laser receiving units. Multiple processing units.

In one embodiment, the laser detection system described above may include a plurality of single line laser radars. As shown in FIG. 1A, the laser detecting system includes a first single-line laser radar 1, a second single-line laser radar 2, and a third single-line laser radar 3. The first single-line laser radar 1 includes a first laser emitting unit 11, a laser receiving unit 12, a first processing unit 13; a second single-line laser radar 2 comprising a second laser emitting unit 21, a second laser receiving unit 22, a second processing unit 23; and a third single-line laser radar 3 comprising a third laser emitting The unit 31, the third laser receiving unit 32, and the third processing unit 33.

In another embodiment, the laser detection system described above may include a multi-line laser radar. As shown in FIG. 1B, the laser detection system comprises a multi-line laser radar 4 comprising a first line 41, a second line 42, and a third line 43, wherein the first line 41 comprises a fourth laser emitting unit 411, a fourth The laser receiving unit 412 and the fourth processing unit 413; the second line 42 includes a fifth laser emitting unit 421, a fifth laser receiving unit 422, and a fifth processing unit 423; the third line 43 includes a sixth laser emitting unit 431 and a sixth laser receiving unit Unit 432, sixth processing unit 433.

In yet another embodiment, the laser detection system described above can include at least one multi-line lidar and at least one single-line lidar. As shown in FIG. 1C, the laser detection system includes a multi-line laser radar 4 and a first single-line laser radar 1, a second single-line laser radar 2, wherein the multi-line laser radar 4 and the first single-line laser radar 1, the second single line The structure of the laser radar 2 is as described in the above two embodiments.

Each of the laser detecting units in the laser detecting system may be configured to generate a laser signal in the same detecting period and transmit the laser signal to the probe 5; each laser receiving unit is configured to receive the laser signal through the detecting object. 5 returning echo signals, and respectively acquiring echo signals matching the laser signals emitted by the laser emitting units corresponding thereto according to the echo signals received by themselves; each processing unit is used according to each of the above The laser signal emitted by the laser emitting unit and the echo signal matched by the laser signal determine the target parameter of the probe 5.

For example, as shown in FIG. 1A, in the same detection period, the first laser emitting unit 11, the second laser emitting unit 21, and the third laser emitting unit 31 in the laser detecting system respectively generate a first laser signal and a second The laser signal and the third laser signal are emitted to the detector 5, and the first laser signal, the second laser signal, and the third laser signal are reflected by the detector 5 to the first laser radar 1, the second laser radar 2, and the third laser The radar 3 is received by the first laser receiving unit 12, the second laser receiving unit 22, and the third laser receiving unit 32. The echo signal received by the first laser receiving unit 12 includes an echo signal matching the first laser signal emitted by the first laser emitting unit 11, and may also include an interference signal, such as a second laser emission. The echo signal matched by the second laser signal emitted by the unit 21, the echo signal matched with the third laser signal emitted by the third laser emitting unit 31, and the white noise generated by natural light or light, etc., The second laser receiving unit 22 and the third laser receiving unit 23 may receive the above-mentioned interference signal in addition to the echo signal matching the laser signal emitted by the laser emitting unit corresponding thereto.

It can be seen that how to filter out the interference signal to obtain the echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself, and the target parameter of the accurate and reliable detecting object can be obtained for the subsequent processing unit. important. Therefore, in order for each laser receiving unit to accurately acquire an echo signal matching the laser signal emitted by the laser emitting unit corresponding thereto according to the echo signal received by itself, the laser emitting unit generates the plurality of laser emitting units. In the case where the laser signals are of the same mode, the time at which they emit the laser signals is different from each other, or, in the case where the plurality of laser emitting units emit the laser signals at the same time, the manner in which they generate the laser signals is different from each other.

When a plurality of laser emitting units emit laser signals at the same time, they generate laser signals in different ways. In one embodiment, each of the laser emitting units generates laser signals at mutually different frequencies. For example, as shown in FIG. 2, the fourth laser emitting unit 411 of the multi-line laser radar 4 generates a laser signal at a frequency of 17 Khz, the fifth laser emitting unit 421 generates a laser signal at a frequency of 18 Khz, and the sixth laser emitting unit 431. The laser signal is generated at a frequency of 19 Khz, and the first laser emitting unit 11 of the first single-line laser radar 1 generates a laser signal at any of 20 Khz-22Khz, and the second laser emitting unit 21 of the second single-line laser radar 2 A laser signal is generated at any of the frequencies of 23Khz-25Khz.

In this way, each of the laser receiving units can respectively process the echo signals received by the laser receiving unit to extract the same frequency signal from the laser signal emitted by the laser emitting unit corresponding to the laser echo unit. As the echo signal matched by the laser signal. Specifically, each of the laser receiving units may include a filtering circuit, so that the laser signal received from the laser receiving unit can be filtered by the filtering circuit to have the same frequency as the laser signal emitted by the laser emitting unit corresponding thereto. signal of. Alternatively, each of the laser receiving units may include a lock-in amplifier, such that a signal having a different frequency of the laser signal emitted by the laser emitting unit corresponding to the laser-emitting unit may be removed by the lock-in amplifier, so that the laser light corresponding to itself is emitted. The signal of the same frequency of the laser signal emitted by the unit is retained, that is, the echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself is obtained.

For example, as shown in FIG. 2, the fourth laser emitting unit 411 of the multi-line laser radar 4 generates a laser signal at a frequency of 17 Khz, and after receiving the echo signal, the fourth laser receiving unit 412 can pass the filtering circuit. A signal having a frequency of 17 Khz is filtered out from the echo signal received by the four laser receiving unit 412, that is, an echo signal matching the laser signal emitted by the corresponding fourth laser emitting unit 411 is acquired.

For example, as shown in FIG. 2, the first laser emitting unit 11 in the first single-line laser radar 1 generates a laser signal at any frequency of 20Khz-22Khz, and after receiving the echo signals, the first laser receiving unit 12 may A signal having a frequency in the range of 20Khz-22Khz is extracted from the echo signal received by the first laser receiving unit 12 by the lock-in amplifier, that is, the laser signal emitted by the corresponding first laser emitting unit 11 is matched. Echo signal.

Since the above-mentioned filter circuit and lock-in amplifier have strong suppression of laser signals, natural light signals, light signals, etc., which are different from the laser signal emitted by the corresponding laser emitting unit, it is possible to avoid different laser radars or the same Mutual interference between different lines of the line radar can also filter out interference signals such as natural light and light, thereby enabling high signal-to-noise ratio detection and long-range detection of the laser detection system.

In addition, each of the above-mentioned laser emitting units can obtain the target frequency used by the laser generating signal in the following two ways:

(1) Each laser transmitting unit determines a target frequency used by itself according to a frequency used by other laser transmitting units recorded in the frequency information library, and updates the frequency information library by using the target frequency, wherein the target frequency is different from The frequency used by other laser emitting units.

In the present disclosure, the frequency information library may be a table or a blockchain. Moreover, the frequency information base may be stored locally at each laser emitting unit or independently of the laser emitting unit, for example, a dedicated service unit. Moreover, after determining the target frequency used by each laser transmitting unit, in addition to updating its own frequency information base, it is also necessary to assist in updating the frequency information library of the surrounding laser radar, for example, by broadcasting the target frequency to The surrounding laser radar method is used to update the frequency information library of the surrounding laser radar, and the frequency information library can also be updated by the blockchain technology, thereby ensuring that each laser emitting unit generates laser signals at mutually different frequencies. .

(2) Receiving the frequency transmitted by the base station, and using the received frequency as the target frequency.

In the present disclosure, the base station can be used to perform frequency allocation for the connected laser transmitting units, and the frequencies assigned to each of the connected laser emitting units are different from each other. Moreover, in order to ensure that each laser emitting unit generates laser signals at mutually different frequencies, when the base station performs frequency allocation, it is necessary to timely update and recover the frequency information used by the locally stored laser emitting units of the laser radar. Specifically, after the base station establishes a communication connection with a laser emitting unit around it, any frequency that is not allocated may be sent to the laser emitting unit, and the laser transmitting unit is locally recorded and sent to the laser emitting. The correspondence between the frequencies of the units, that is, the update operation of the frequency information used by the laser transmitting unit of the surrounding laser radar; when the base station disconnects the communication connection with any laser emitting unit around it, the laser can be emitted. The frequency information used by the unit is reclaimed to be reassigned to other laser transmitting units in the future to achieve resource recycling.

In addition to the fact that each of the laser emitting units can generate laser signals at mutually different frequencies, in another embodiment, each of the laser emitting units can also modulate the laser emitting current by using pseudo-random codes different from each other. A current pulse sequence is generated, and the current pulse sequence is carrier modulated to generate a laser signal. In this way, mutual interference between different laser radars or different lines of the same multi-line laser radar can be reduced, and the influence of strong light sources such as sunlight, street lamps, and lamp lights can be reduced, thereby realizing a high signal-to-noise ratio of the laser detection system. Detection and remote detection.

For example, as shown in FIG. 3A, the fourth laser emitting unit 411 of the multi-line laser radar 4 modulates the laser emission current using the pseudo random code 1, and the fifth laser emitting unit 421 performs the laser emission current using the pseudo random code 2. The modulation, sixth laser emitting unit 431 modulates the laser emission current using the pseudo random code 3, and the first laser emitting unit 11 in the first single-line laser radar 1 uses any pseudo random code pair of pseudo random codes 4-20 The emission current is modulated, and the second laser emitting unit 21 of the second single-line laser radar 2 modulates the laser emission current using any of the pseudo random codes 21-24.

As shown in FIG. 3B, each of the laser emitting units (wherein the laser emitting unit includes a laser transmitter) respectively utilizes pseudo-random codes different from each other

Laser emission current

Modulation to generate a current pulse sequence

And the current pulse sequence

Perform carrier modulation to generate laser signal

(among them,

For the carrier frequency,

Is the cosine of the carrier frequency) and is emitted by the laser transmitter; the laser receiver in each laser receiving unit receives the echo signal, and then each laser receiving unit separately receives the echo signal received by itself

(among them,

For the sum of noise and interference signals, the above laser signal will be interfered by noise and other signals after being transmitted wirelessly. Therefore, the signal received by the laser receiving unit is divided by the laser signal emitted by the laser emitting unit corresponding to itself. In addition to the matched echo signals, there are also noise and interference signals. First, coherent wave demodulation is performed to obtain:

among them,

An echo signal obtained by coherently demodulating the echo signal received by each laser receiving unit for each laser receiving unit;

For the phase.

After that, the coding filtering is performed. Specifically, the filtering is first performed, and after filtering, it is obtained:

(among them,

Is the filtered echo signal;

a sum of the noise and the interference signal); finally, a pseudo-random code having the same pseudo-random code as that used by the laser transmitting unit corresponding to itself in generating the laser signal

Despreading the filtered signal, that is, the filtered echo signal

Pseudo random code

Multiply, thereby obtaining an echo signal matching the laser signal emitted by the laser emitting unit corresponding thereto.

When a plurality of laser emitting units generate laser signals in the same manner, they emit laser signals at different times. In one embodiment, when the times at which the plurality of laser emitting units emit laser signals are different from each other, the time interval between two adjacent transmitting times is greater than the signal round-trip at the farthest ranging distance of the laser emitting unit. The duration is such that, in each period, only one laser emitting unit emits a laser signal to the probe 5, and during this period, only one echo signal is returned by the probe 5, so that the corresponding laser receiving unit is The echo signal received during this period is an echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself, thereby effectively avoiding different lines between different laser radars or the same multi-line laser radar. Signal interference between.

For example, assuming that the far-reaching distance of the laser emitting unit is 300 m, wherein the speed of light is 3.0*10 ⁸ m/s , the round-trip time of the signal at the farthest distance of the laser emitting unit is 2 us. Therefore, the time interval between two adjacent transmission times is greater than 2 us. By way of example, as shown in FIG. 4, the time interval between two adjacent transmission times is 5 us, wherein the first line 41 of the multi-line lidar 4 performs the emission and echo signals of the laser signal during the 0 us-5 us period. The receiving, that is, the fourth laser emitting unit 411 emits a laser signal at time 0, at this time, the fourth laser receiving unit 412 starts monitoring the echo signal, the monitoring duration is 2 us; the second line 42 performs the laser signal in the 5us-10us period. The reception of the emission and echo signals, that is, the fifth laser emitting unit 421 emits a laser signal at time 5us, at this time, the fifth laser receiving unit 422 starts monitoring the echo signal, the monitoring duration is 2 us; the third line 43 is at 10 us. The emission of the laser signal and the reception of the echo signal are performed during the -15us period, that is, the sixth laser emitting unit 431 emits the laser signal at the time of 10us, and at this time, the sixth laser receiving unit 432 starts monitoring the echo signal, and the monitoring duration is 2us. The first laser emitting unit 11 in the first single-line laser radar 1 performs the transmission of the laser signal and the reception of the echo signal in the period of 15us-20us, that is, the first laser emitting unit 11 at the time of 15us At this time, the first laser receiving unit 12 starts monitoring the echo signal, and the monitoring duration is 2 us; the second laser emitting unit 21 of the second single-line laser radar 2 performs the laser signal emission in the 20us-25us period. And the reception of the echo signal, that is, the second laser emitting unit 21 emits a laser signal at time 20us, at which time, the second laser receiving unit 22 starts monitoring the echo signal for a duration of 2 us.

Finally, each processing unit can determine the target parameters of the probe 5 according to the laser signal emitted by each of the above-mentioned laser emitting units and the echo signal matched by the laser signal, for example, distance, azimuth, altitude, speed, attitude , shape, etc. For example, the distance of the probe 5 can be determined according to the time interval between the laser emitting unit transmitting laser signal and the corresponding laser receiving unit receiving the echo signal.

In addition, it should be noted that although the three-line laser radar is taken as an example in the present disclosure, the above-described multi-line laser radar provided by the present disclosure is not limited to the three-line laser radar, and may be applied to other multi-line laser radars, for example, 6 lines, 32 lines, 64 lines, 128 lines, 256 lines, etc.

FIG. 5 is a flow chart showing a laser detecting method according to an exemplary embodiment, wherein the method can be applied to the laser detecting system described above. As shown in FIG. 5, the method can include the following steps.

In step 501, each laser emitting unit generates a laser signal and transmits the laser signal to the detector during the same detection period.

In the present disclosure, in a case where the manner in which the plurality of laser emitting units generate laser signals are the same, the times at which the plurality of laser emitting units emit laser signals are different from each other, and the laser signals are emitted in the plurality of laser emitting units In the case where the time is the same, the manner in which the plurality of laser emitting units generate laser signals is different from each other.

In step 502, each laser receiving unit receives an echo signal returned by the laser signal via the probe.

In step 503, each of the laser receiving units respectively acquires an echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself according to the echo signal received by itself.

In step 504, the processing unit determines a target parameter of the probe according to the laser signal emitted by each laser emitting unit and the echo signal matched by the laser signal.

Optionally, each of the laser emitting units generates a laser signal, including:

Each of the laser emitting units respectively generates the laser signals at mutually different frequencies;

Each of the laser receiving units respectively acquires an echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself according to the echo signal received by the laser receiving unit, including:

Each of the laser receiving units respectively processes the echo signal received by the laser receiving unit to extract a signal having the same frequency as the laser signal emitted by the laser emitting unit corresponding to the laser signal received by the laser echo unit. The laser signal matches the echo signal.

Optionally, the laser emitting unit acquires a target frequency that is used when generating the laser signal by one of the following methods:

The laser transmitting unit determines the target frequency used by itself according to a frequency used by other laser transmitting units recorded in the frequency information library, and updates the frequency information library by using the target frequency, wherein the target frequency Different from the frequency used by the other laser emitting units;

Receiving a frequency transmitted by the base station, and using the received frequency as the target frequency, wherein the base station is configured to perform frequency allocation for the connected laser transmitting unit, and the frequency allocated to each connected laser transmitting unit is mutually Not the same.

Each of the laser emitting units respectively modulates a laser emission current by using pseudo-random codes different from each other, generates a current pulse sequence, and performs carrier modulation on the current pulse sequence to generate the laser signal;

Each of the laser receiving units sequentially performs coherent wave demodulation and filtering on the echo signals received by itself, and uses the same pseudo random code used by the laser transmitting unit corresponding to itself to generate the laser signal. The pseudo-random code performs despreading on the filtered signal to obtain an echo signal matching the laser signal emitted by the laser emitting unit corresponding thereto.

Optionally, when the times at which the plurality of laser emitting units emit laser signals are different from each other, a time interval between two adjacent transmitting times is greater than a signal round-trip at a farthest ranging distance of the laser emitting unit duration.

Regarding the method in the above embodiment, the specific manner in which the operations are performed in the respective steps has been described in detail in the embodiment of the above laser detecting system, and will not be described in detail herein.

Other embodiments of the present disclosure will be apparent to those skilled in the <RTIgt; The present application is intended to cover any variations, uses, or adaptations of the present disclosure, which are in accordance with the general principles of the disclosure and include common general knowledge or common technical means in the art that are not disclosed in the present disclosure. . The specification and examples are to be regarded as illustrative only,

It is to be understood that the invention is not limited to the details of the details and The scope of the disclosure is to be limited only by the appended claims.

Claims

A laser detecting method is applied to a laser detecting system, the laser detecting system comprising a plurality of laser emitting units, a plurality of laser receiving units corresponding to the plurality of laser emitting units, and the plurality of laser receiving units a plurality of processing units corresponding to one-to-one, wherein the method comprises:

Each of the laser emitting units generates a laser signal and transmits the laser signal to the probe in the same detection period, wherein, in a case where the plurality of laser emitting units generate laser signals in the same manner, The time at which the plurality of laser emitting units emit the laser signals are different from each other, and in a case where the times at which the plurality of laser emitting units emit the laser signals are the same, the manner in which the plurality of laser emitting units generate the laser signals are different from each other;

Each of the laser receiving units receives an echo signal returned by the laser signal via the probe;

Each of the laser receiving units respectively acquires an echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself according to the echo signal received by the laser receiving unit;

The processing unit determines a target parameter of the probe according to a laser signal emitted by each of the laser emitting units and an echo signal matched by the laser signal.
The method of claim 1 wherein each of said laser emitting units generates a laser signal, comprising:

Each of the laser emitting units respectively generates the laser signals at mutually different frequencies;

Each of the laser receiving units respectively acquires an echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself according to the echo signal received by the laser receiving unit, including:

Each of the laser receiving units respectively processes the echo signal received by the laser receiving unit to extract a signal having the same frequency as the laser signal emitted by the laser emitting unit corresponding to the laser signal received by the laser echo unit. The laser signal matches the echo signal.
The method according to claim 2, wherein said laser emitting unit acquires a target frequency which is used by itself when generating said laser signal by one of the following means:

The laser transmitting unit determines the target frequency used by itself according to a frequency used by other laser transmitting units recorded in the frequency information library, and updates the frequency information library by using the target frequency, wherein the target frequency Different from the frequency used by the other laser emitting units;

Receiving a frequency transmitted by the base station, and using the received frequency as the target frequency, wherein the base station is configured to perform frequency allocation for the connected laser transmitting unit, and the frequency allocated to each connected laser transmitting unit is mutually Not the same.
The method of claim 1 wherein each of said laser emitting units generates a laser signal, comprising:

Each of the laser emitting units respectively modulates a laser emission current by using pseudo-random codes different from each other, generates a current pulse sequence, and performs carrier modulation on the current pulse sequence to generate the laser signal;

Each of the laser receiving units respectively acquires an echo signal matching the laser signal emitted by the laser emitting unit corresponding to itself according to the echo signal received by the laser receiving unit, including:

Each of the laser receiving units sequentially performs coherent wave demodulation and filtering on the echo signals received by itself, and uses the same pseudo random code used by the laser transmitting unit corresponding to itself to generate the laser signal. The pseudo-random code performs despreading on the filtered signal to obtain an echo signal matching the laser signal emitted by the laser emitting unit corresponding thereto.
The method according to claim 1, wherein when a time at which said plurality of laser emitting units emit laser signals are different from each other, a time interval between adjacent two emission times is greater than a farthest distance in said laser emitting unit The round trip time of the signal at the ranging distance.
A laser detecting system comprising a plurality of laser emitting units, a plurality of laser receiving units corresponding to the plurality of laser emitting units, and a plurality of one-to-one correspondence with the plurality of laser receiving units Processing unit, wherein

Each of the laser emitting units is configured to generate a laser signal and transmit the laser signal to the detector in the same detection period, wherein, in a case where the plurality of laser emitting units generate the laser signal in the same manner, The time at which the plurality of laser emitting units emit laser signals are different from each other, and in a case where the times at which the plurality of laser emitting units emit laser signals are the same, the manner in which the plurality of laser emitting units generate laser signals are different from each other;

Each of the laser receiving units is configured to receive an echo signal returned by the laser signal through the probe, and respectively acquire a laser emitted by a laser emitting unit corresponding to the laser signal according to an echo signal received by itself. The echo signal that the signal matches;

The processing unit is configured to determine a target parameter of the probe according to a laser signal emitted by each of the laser emitting units and an echo signal matched by the laser signal.
The system of claim 6 wherein each of said laser emitting units is operative to generate said laser signals at mutually different frequencies;

Each of the laser receiving units is configured to respectively process an echo signal received by itself to extract a signal having the same frequency as the laser signal emitted by the laser emitting unit corresponding to the laser signal received by the laser echo unit. As the echo signal matched by the laser signal.
The system according to claim 7, wherein said laser emitting unit acquires a target frequency itself used in generating said laser signal by one of the following means:

The laser transmitting unit determines the target frequency used by itself according to a frequency used by other laser transmitting units recorded in the frequency information library, and updates the frequency information library by using the target frequency, wherein the target frequency Different from the frequency used by the other laser emitting units;

Receiving a frequency transmitted by the base station, and using the received frequency as the target frequency, wherein the base station is configured to perform frequency allocation for the connected laser transmitting unit, and the frequency allocated to each connected laser transmitting unit is mutually Not the same.
The system according to claim 6, wherein each of said laser emitting units is configured to modulate a laser emission current with pseudo-random codes different from each other, generate a current pulse sequence, and perform carrier on said current pulse sequence Modulating to generate the laser signal;

Each of the laser receiving units is configured to sequentially perform coherent wave demodulation and filtering on the echo signals received by itself, and utilize pseudo-random used in generating the laser signals by the laser transmitting unit corresponding to itself. The pseudo-random code with the same code is subjected to despreading processing of the filtered signal to obtain an echo signal matching the laser signal emitted by the laser emitting unit corresponding thereto.
The system according to claim 6, wherein when the times at which the plurality of laser emitting units emit laser signals are different from each other, a time interval between adjacent two emission times is greater than a farthest distance in the laser emitting unit The round trip time of the signal at the ranging distance.