CN112799032A - Method for preventing crosstalk between channels for laser radar, system and electronic equipment thereof - Google Patents
Method for preventing crosstalk between channels for laser radar, system and electronic equipment thereof Download PDFInfo
- Publication number
- CN112799032A CN112799032A CN201911103521.9A CN201911103521A CN112799032A CN 112799032 A CN112799032 A CN 112799032A CN 201911103521 A CN201911103521 A CN 201911103521A CN 112799032 A CN112799032 A CN 112799032A
- Authority
- CN
- China
- Prior art keywords
- channels
- crosstalk
- channel
- time
- lidar
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 74
- 238000012545 processing Methods 0.000 claims abstract description 23
- 238000012360 testing method Methods 0.000 claims description 24
- 238000001914 filtration Methods 0.000 claims description 11
- 238000012544 monitoring process Methods 0.000 claims description 9
- 230000002265 prevention Effects 0.000 claims description 8
- 230000008901 benefit Effects 0.000 description 18
- 238000001514 detection method Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 9
- 230000003287 optical effect Effects 0.000 description 8
- 238000004590 computer program Methods 0.000 description 6
- 238000013461 design Methods 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 230000002452 interceptive effect Effects 0.000 description 2
- 238000012216 screening Methods 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000006798 recombination Effects 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/4804—Auxiliary means for detecting or identifying lidar signals or the like, e.g. laser illuminators
Abstract
A method for preventing crosstalk between channels for a laser radar, a system and an electronic device thereof are provided. The method for preventing the crosstalk between channels of the laser radar comprises the following steps: grouping a plurality of channels in the laser radar to form N groups of channels, wherein N is more than or equal to 2; controlling the channels of different groups to start working at a preset time interval, wherein the preset time is not equal to the positive integral multiple of the working time of a single channel; and processing the echo signals received by the receiving channels in the plurality of channels to filter crosstalk signals in the echo signals, and reserving real echo signals for the plurality of channels in the laser radar to complete multithreading time-staggered work.
Description
Technical Field
The invention relates to the technical field of laser radars, in particular to a method and a system for preventing crosstalk between channels for a laser radar and electronic equipment.
Background
The working principle of the radar system is to firstly transmit a laser beam (i.e. a transmission signal) to a target, then compare a received laser echo (i.e. an echo signal) reflected or scattered from the target with the transmission signal, and after appropriate processing, obtain relevant information of the target, such as parameters of the target, such as distance, direction, height, speed, attitude, and even shape.
At present, the existing multi-line laser radar generally emits a plurality of light beams distributed in the vertical direction through a plurality of laser transmitters, and forms the scanning of a plurality of light beams through the 360-degree rotation of a motor; meanwhile, the same number of laser receivers are used for receiving the corresponding light beams reflected or scattered back by the target so as to realize radar detection.
However, since the multiline lidar is often required to achieve a higher vertical resolution, a plurality of laser transmitters and a plurality of laser receivers in the existing multiline lidar are often arranged very densely, so that the optical design of the existing multiline lidar is difficult to achieve one-to-one correspondence between transmitting channels and receiving channels, and optical channel crosstalk exists in the existing multiline lidar to a great extent; for example, for a 64-line lidar, limited by the high requirement of vertical resolution and the overall volume, 64 laser transmitters and 64 laser receivers must be very densely arranged, and it is essentially impossible to make a one-to-one correspondence between 64 transmit channels and 64 receive channels to form 64 non-interfering channels. In other words, after being reflected or scattered back by a target, a laser beam emitted by one laser emitter in the conventional multi-line laser radar is focused by the receiving lens and then simultaneously received by a plurality of adjacent laser receivers, which causes ambiguity and abnormality of point cloud data, and causes the problem of crosstalk between channels in the conventional multi-line laser radar.
For the above problem of inter-channel crosstalk, a common processing method at present controls the operation of the laser radar in a single-thread time-sharing manner: controlling transmitting channels in all channels to transmit in sequence in a time-sharing manner, and only paying attention to a receiving channel corresponding to the transmitting channel in the channel during receiving; that is, after one channel is controlled to complete the work (including one transmitting channel completing the transmission and the corresponding receiving channel completing the reception), the next channel is allowed to work, and thus the work of all the channels is completed in sequence. And as the detection distance of the multi-line laser radar is increased, the processing time of each channel working in a time-sharing mode is prolonged. At this time, if the point cloud refresh rate is kept unchanged (that is, the scanning time of the existing multiline laser radar is not changed for one week), the horizontal angular resolution of the existing multiline laser radar will be increased, and the direct effect is that the point cloud of the existing multiline laser radar becomes relatively sparse, and the requirement of applications such as unmanned driving and the like on the high detection density of the laser radar cannot be met.
Disclosure of Invention
An advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a laser radar, a system and an electronic device thereof, which can solve the inter-channel crosstalk problem of the laser radar.
Another advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a lidar, a system and an electronic device thereof, wherein in an embodiment of the present invention, the method for preventing inter-channel crosstalk for a lidar can solve the problem of inter-channel crosstalk for the lidar while ensuring that the horizontal angular resolution of the lidar is not changed.
Another advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a lidar, a system and an electronic device thereof, wherein in an embodiment of the present invention, the method for preventing inter-channel crosstalk for a lidar can solve the problem of inter-channel crosstalk generated by the lidar by using only a software method without changing hardware.
Another advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a lidar, a system and an electronic device thereof, wherein in an embodiment of the present invention, the method for preventing inter-channel crosstalk for a lidar can control the operation of the lidar in a multi-thread time-staggered manner, so that crosstalk signals generated due to inter-channel crosstalk can be easily filtered out to retain real echo signals.
Another advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a lidar, a system and an electronic device thereof, wherein in an embodiment of the present invention, the method for preventing inter-channel crosstalk for a lidar can ensure that a point cloud refresh rate of the lidar is at a high level.
Another advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a lidar, a system and an electronic device thereof, wherein in an embodiment of the present invention, the method for preventing inter-channel crosstalk for a lidar can filter out crosstalk signals only by a software method without changing an optical system of the lidar, so as to maximally retain real echo signals.
Another advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a lidar, a system and an electronic device thereof, wherein in an embodiment of the present invention, the method for preventing inter-channel crosstalk for a lidar can greatly shorten a duty cycle of the lidar.
Another advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a laser radar, a system and an electronic device thereof, wherein in an embodiment of the present invention, the method for preventing inter-channel crosstalk for a laser radar can reduce the risk that a real echo signal is filtered out by mistake.
Another advantage of the present invention is to provide a method for preventing inter-channel crosstalk for a laser radar, a system and an electronic device thereof, in which expensive materials or complicated structures are not required to be used in the present invention in order to achieve the above advantages. Therefore, the present invention successfully and effectively provides a solution to provide not only a simple inter-channel crosstalk prevention method for a lidar, and a system and an electronic device thereof, but also increases the practicality and reliability of the inter-channel crosstalk prevention method for a lidar, and the system and the electronic device thereof.
To achieve at least one of the above advantages or other advantages and objects, the present invention provides a method for preventing inter-channel crosstalk for a laser radar, comprising the steps of:
grouping a plurality of channels in the laser radar to form N groups of channels, wherein N is more than or equal to 2;
controlling the channels of different groups to start working at a preset time interval, wherein the preset time is not equal to the positive integral multiple of the working time of a single channel; and
and processing the echo signals received by the receiving channels in the plurality of channels to filter crosstalk signals in the echo signals, and reserving real echo signals for the plurality of channels in the laser radar to finish multi-thread time-staggered work.
In an embodiment of the invention, in the step of grouping the plurality of channels in the lidar, the plurality of channels are equally divided into N groups, so that the number of channels in the channels in different groups is the same.
In an embodiment of the present invention, in the step of controlling the channels of different groups to start operating at a predetermined time interval, the predetermined time is equal to a ratio of an operating time of the single channel to the number N of groups.
In an embodiment of the present invention, the step of processing the echo signal received through the receiving channel of the multiple channels further includes the steps of:
monitoring the time and the intensity value of the echo signal received by the receiving channel in all the channels;
judging whether the time difference value between the echo signals received by the receiving channels in any two groups of channels is smaller than a time difference threshold value, if so, taking the corresponding echo signals as suspected crosstalk signal pairs;
judging whether the intensity ratio between two echo signals in the suspected crosstalk signal pair is greater than an intensity ratio threshold value, if so, identifying the echo signal with a smaller intensity value as a crosstalk signal, and identifying the echo signal with a larger intensity value as a real echo signal; if not, determining the two echo signals in the suspected crosstalk signal pair as real echo signals; and
and filtering the crosstalk signal to reserve the real echo signal.
In an embodiment of the present invention, before the step of grouping a plurality of channels in the laser radar, the method for preventing inter-channel crosstalk for a laser radar further includes the steps of:
testing the crosstalk condition of each channel in the laser radar to other channels to obtain a crosstalk-free channel group and a residual channel group;
controlling the channels in the mutual non-crosstalk channel group to carry out simultaneous multi-thread work; and
and controlling the channels in the remaining channel group to carry out multi-thread time-staggered work.
In an embodiment of the present invention, the step of testing the crosstalk of each channel in the laser radar to other channels to obtain a mutually crosstalk-free channel group and a remaining channel group includes the steps of:
sequentially controlling a transmitting channel of the channel in the laser radar to independently perform transmitting work;
determining whether all receiving channels of the channel in the laser radar receive echo signals and recording the echo signals; and
and judging whether crosstalk exists between different channels, if not, dividing the corresponding channel into the mutually crosstalk-free channel group, and if so, dividing the corresponding channel into the remaining channel group.
In an embodiment of the present invention, the step of controlling channels in the mutually non-crosstalk channel group to perform multi-thread simultaneous operation includes the steps of:
grouping channels in the mutual non-crosstalk channel group to form n groups of channels, wherein n is more than or equal to 2; and
and controlling the channels of different groups to start working at the same time so as to ensure that the channels of the different groups which start working at the same time do not interfere with each other.
In an embodiment of the present invention, the method for preventing inter-channel crosstalk for lidar further includes:
and controlling the channels of the same group to perform single-thread time-sharing work.
According to another aspect of the present invention, the present invention also provides a method for preventing inter-channel crosstalk for a lidar, comprising the steps of:
testing the crosstalk condition of each channel in the laser radar to other channels to obtain a crosstalk-free channel group and a residual channel group;
controlling the channels in the mutual non-crosstalk channel group to carry out simultaneous multi-thread work; and
and controlling the channels in the rest channel groups to perform single-thread time-sharing work.
According to another aspect of the present invention, there is also provided a system for preventing inter-channel crosstalk for a lidar, comprising:
a time-staggered working module, wherein the time-staggered working module is used for communicably connecting the laser radar, wherein the time-staggered working module comprises the following components in sequence communicably connected:
the channel grouping module is used for grouping a plurality of channels in the laser radar to form N groups of channels, wherein N is more than or equal to 2;
the time staggering control module is used for controlling the channels of different groups to start working at a preset time interval, wherein the preset time is not equal to the positive integral multiple of the working time of a single channel; and
and the echo signal processing module is used for processing the echo signals received by the receiving channels in the plurality of channels so as to filter crosstalk signals in the echo signals and reserve real echo signals for the plurality of channels in the laser radar to finish multi-thread time-staggered work.
In an embodiment of the present invention, the echo signal processing module includes a monitoring module, a time difference determining module, an intensity ratio determining module and a filtering module, which are sequentially communicably connected, where the monitoring module is configured to monitor a time and an intensity value of the echo signal received through the receiving channel in all the channels; the time difference judging module is used for judging whether the time difference value between the echo signals received by the receiving channels in any two groups of channels is smaller than a time difference threshold value, if so, the corresponding echo signals are used as suspected crosstalk signal pairs; the strength ratio judging module is used for judging whether the strength ratio between two echo signals in the suspected crosstalk signal pair is greater than a strength ratio threshold value, if so, the echo signal with the smaller strength value is regarded as the crosstalk signal, and the echo signal with the larger strength value is regarded as the real echo signal; if not, determining the two echo signals in the suspected crosstalk signal pair as real echo signals; the filtering module is used for filtering the crosstalk signal so as to reserve the real echo signal.
In an embodiment of the present invention, the system for preventing inter-channel crosstalk for a laser radar further includes a crosstalk testing module and a simultaneous operation module, which are communicably connected to each other, where the crosstalk testing module is configured to test a crosstalk condition of each channel in the laser radar to other channels, so as to obtain a mutually non-crosstalk channel group and a remaining channel group; the simultaneous working module is used for controlling the channels in the mutual crosstalk-free channel group to carry out simultaneous multi-thread working; the time-staggered working module is also used for controlling the channels in the rest channel group to carry out multi-thread time-staggered working.
In an embodiment of the present invention, the crosstalk testing module includes a sequential control module, a echo signal testing module, and a crosstalk determining module, which are sequentially communicably connected, where the sequential control module is configured to sequentially control a transmitting channel of the channel in the laser radar to perform transmitting work independently; the echo signal testing module is used for determining whether all receiving channels of the channel in the laser radar receive echo signals and recording the echo signals; the crosstalk judging module is used for judging whether crosstalk exists between different channels, if not, the corresponding channel is divided into the mutual crosstalk-free channel group, and if so, the corresponding channel is divided into the residual channel group.
In an embodiment of the present invention, the system for preventing inter-channel crosstalk for a laser radar further includes a time-sharing operating module, where the time-sharing operating module is configured to control channels in the same group to perform single-thread time-sharing operation.
According to another aspect of the present invention, the present invention also provides an electronic device, comprising:
a processor for executing program instructions; and
a memory, wherein the memory is configured to hold program instructions executable by the processor to perform a method for inter-channel crosstalk prevention for lidar, wherein the method for inter-channel crosstalk prevention for lidar comprises the steps of:
grouping a plurality of channels in the laser radar to form N groups of channels, wherein N is more than or equal to 2;
controlling the channels of different groups to start working at a preset time interval, wherein the preset time is not equal to the positive integral multiple of the working time of a single channel; and
and processing the echo signals received by the receiving channels in the plurality of channels to filter crosstalk signals in the echo signals, and reserving real echo signals for the plurality of channels in the laser radar to finish multi-thread time-staggered work.
Further objects and advantages of the invention will be fully apparent from the ensuing description and drawings.
These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the claims.
Drawings
Fig. 1 is a schematic diagram of single-thread time-sharing operation of a lidar in accordance with an embodiment of the present invention.
FIG. 2A is a schematic diagram of a lidar configured to perform simultaneous multithreading according to an embodiment of the invention.
Fig. 2B is a diagram showing the state of echo signals when the lidar performs multi-thread simultaneous operation according to the above embodiment of the invention.
Fig. 3 is a flowchart illustrating a method for preventing inter-channel crosstalk for a lidar according to a first embodiment of the present invention.
Fig. 4A shows an example of multi-threaded staggered operation of the lidar according to the above-described first embodiment of the invention.
Fig. 4B is a diagram illustrating the state of the echo signal when the lidar performs multi-thread staggered operation according to the first embodiment of the present invention.
FIG. 5 is a flow chart illustrating one of the steps of the method for preventing inter-channel crosstalk of lidar according to the first embodiment of the present invention
Fig. 6 is a flowchart illustrating a method for preventing inter-channel crosstalk for a lidar according to a second embodiment of the present invention.
Fig. 7 is a flowchart illustrating one of the steps of the method for preventing inter-channel crosstalk in lidar according to the second embodiment of the present invention.
Fig. 8 is a flow chart illustrating a second step of the method for preventing inter-channel crosstalk of lidar according to the second embodiment of the present invention.
Fig. 9 is a flowchart illustrating a method for preventing inter-channel crosstalk for a lidar according to a third embodiment of the present invention.
FIG. 10 is a block diagram schematic diagram of an inter-channel crosstalk prevention system for lidar in accordance with an embodiment of the present invention.
Fig. 11 shows an example of an electronic device according to the invention.
Detailed Description
The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.
In the present invention, the terms "a" and "an" in the claims and the description should be understood as meaning "one or more", that is, one element may be one in number in one embodiment, and the element may be more than one in number in another embodiment. The terms "a" and "an" should not be construed as limiting the number unless the number of such elements is explicitly recited as one in the present disclosure, but rather the terms "a" and "an" should not be construed as being limited to only one of the number.
In the description of the present invention, it is to be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
In order to achieve higher vertical resolution, lidar of the type such as multiline lidar often includes a plurality of laser transmitters and a plurality of laser receivers arranged very densely. Meanwhile, in the laser radar, each laser transmitter corresponds to one transmitting channel, and each laser receiver corresponds to one receiving channel, so that a complete channel of the laser radar is formed by the corresponding transmitting channel and the corresponding receiving channel. However, since the laser transmitters and the laser receivers are arranged very densely, it is difficult to achieve a one-to-one correspondence between the transmitting channels and the receiving channels in the optical design of the laser radar, and thus the laser radar has optical inter-channel crosstalk to a large extent. In other words, after a laser beam emitted by one laser emitter in the laser radar is reflected or scattered back by a target, the laser beam may be simultaneously received by a plurality of adjacent laser receivers after being focused by a receiving lens, which causes ambiguity and anomaly of point cloud data, and causes the laser radar to have a cross talk problem between channels.
For example, for a 64-line lidar (in which the point cloud refresh rate of the lidar is 10Hz, the horizontal angular resolution is 0.18 °, and the detection distance is 210m), limited by the high requirement of the vertical resolution and the limitation of the overall volume of the lidar, 64 laser transmitters and 64 laser receivers must be very densely arranged, and it is essentially impossible to form 64 non-interfering channels by one-to-one correspondence between 64 transmission channels and 64 reception channels. From the above it is readily known that: working time T of single channel in laser radar single2 times of the detection distance/light speed 210 × 2/(3 × 10^8) 1.4 us; the time T required for the laser radar to complete a work cyclecycleHorizontal angular resolution/(360 ° -point cloud refresh rate) 0.18/(360 × 10) 50 us.
At this time, in an example of the present invention, if the lidar is controlled to operate according to a single-thread time-sharing operation mode, so that the 64 channels in the lidar operate in a time-sharing manner in sequence (as shown in fig. 1), that is, after one channel (as shown in fig. 1, channel 1) in the lidar completes operation (including transmission operation and reception operation), the next channel (as shown in fig. 1, channel 2) starts to operate; and so on until all the channels are completely finishedIn operation (or, as shown in fig. 1, channel 64 is operational), the lidar performs a full duty cycle. Thus, the actual time T required for the lidar to complete a complete duty cycleroundThe number of channels, the operating time of a single channel, 64, 1.4, 89.6us, results in the actual time T required for the lidar to complete a cycleroundIs far greater than the time T required by the laser radar to complete one working cyclecycleTherefore, the single-thread time-sharing operating mode obviously cannot meet the time requirement of the laser radar on each operating cycle.
In another example of the present invention, if a multi-thread simultaneous operation mode is used to control the operation of the lidar, all channels in the lidar are divided into N groups, where N is greater than or equal to 2; the channels of different groups work simultaneously, and the channels of the same group still work according to a single-thread time-sharing working mode, that is, the channels of different groups are controlled by different threads, so that the time required by the laser radar to complete a complete working cycle is equal to the sum of the time required by the same group of channels to complete the work, and the time required by the laser radar to complete a working cycle is shortened by times. For example, for the 64-line lidar described above, as shown in fig. 2A, the 64 channels in the lidar are divided into two groups AB, where the group a channels include channel a1, channel a2 … …, and channel a32, and the group B channels include channel B1, channel B2 … …, and channel B32; that is, the number of channels in each group of channels is 32, and therefore the time required for all the channels in each group of channels of the laser radar of the present invention to complete their work is implemented as Tteam32 × 1.4 ═ 44.8us, i.e., the time required for the lidar to complete a complete cycle is Tround44.8us, such that the time T actually required for the lidar to complete one duty cycleroundLess than the time T required for the laser radar to complete a cyclecycleTherefore, the multithreading simultaneous working mode can meet the requirement of the laser radar on each working cycleThe time requirement of (2).
However, since the channels of different groups start to operate simultaneously, that is, the transmitting channel and the receiving channel in the channels of different groups start to transmit and receive simultaneously, in the case that the distance of the detected object does not change much, as shown in fig. 2B, the receiving channel in the channel a1 may receive an echo signal B1 '(i.e., a crosstalk signal B1' of the channel B1 to the channel a1) corresponding to the channel B1 in addition to an echo signal a1 corresponding to the channel a1 (i.e., a true echo signal a1 of the channel a1), and the true echo signal a1 and the crosstalk signal B1 'are close in proportion and not completely coincide with each other (as shown in fig. 2B), and the true echo signal a1 and the crosstalk signal B1' are partially superimposed together; similarly, the true echo signal B1 and the crosstalk signal a 1' received by the receiving channel in the channel B1 will be partially superimposed, which results in inaccurate time-of-flight calculation. Therefore, the simultaneous multi-thread working mode can reduce the detection precision of the laser radar due to the crosstalk between channels, so that the detection precision of the laser radar cannot meet the application requirement.
In order to solve the above problem, as shown in fig. 3 to 5, a first embodiment of the present invention provides a method for preventing inter-channel crosstalk for a lidar, which creatively proposes to solve the inter-channel crosstalk problem existing in the lidar by a multi-thread staggered-time operation mode. Specifically, as shown in fig. 3, the method for preventing inter-channel crosstalk for lidar includes the steps of:
s110: grouping all channels in the laser radar to form N groups of channels, wherein N is more than or equal to 2;
s120: controlling the channels of different groups to start working at intervals of preset time, wherein the preset time is not equal to positive integral multiple of the working time of a single channel; and
s130: and processing the echo signals received by the receiving channels in all the channels to filter crosstalk signals in the echo signals, and reserving real echo signals for realizing the multithreading time-staggered work of the laser radar.
It is to be noted that, according to the above-described first embodiment of the present invention, in the step S110 of the method for preventing inter-channel crosstalk for lidar: all of the channels in the lidar are preferably equally divided into N groups such that the number of channels in different groups of channels remains the same, facilitating minimizing the time required for the lidar to complete one cycle of operation.
It will be appreciated that the number of groups N of channels in the present invention is largely dependent on the number of simultaneously operating channels that can be supported by the circuit design in the lidar system itself. In other words, if the circuit design in the system of the laser radar can support two channels to work simultaneously, the group number N of the channels can only be 2; if the circuit design in the system of the laser radar can support three channels to work simultaneously, the group number N of the channels can be 2 or 3.
Further, in the step S120 of the method for preventing inter-channel crosstalk for lidar: the predetermined time is preferably implemented as a ratio of the operating time of a single channel to the number of groups N to ensure that the operating times of the channels of different groups are staggered with respect to each other. In other words, the predetermined time of the present invention is preferably implemented as T ═ TsingleN, wherein TsingleFor the operating time of a single channel, N is the number of groups into which the channel is divided.
More preferably, in the present invention, the channels of the same group still operate according to a single-thread time-sharing operation manner, so as to avoid the crosstalk problem between the channels of the same group. It will be appreciated that, since the channels of the same group of the lidar operate in the single-threaded time-sharing manner, the time required for all the channels of the same group of the lidar to complete operation is equal to the number of channels in a single group of channels plus the operating time of a single channel.
Illustratively, for the 64-line lidar mentioned above (where the point cloud refresh rate of the lidar is 10Hz, horizontal angle)Resolution of 0.18 ° and detection distance of 210m), the operating time T of a single channel in the lidarsingle1.4us and the number of groups N to 2 into which all channels in the lidar are divided (AB two groups as shown in fig. 4A), the predetermined time of the present invention can be implemented as t 0.7 us. Further, as shown in fig. 4A, group a channels include channel a1, channel a2 … …, and channel a32, and group B channels include channel B1, channel B2 … …, and channel B32; that is, the number of channels in each group of channels is 32, and therefore the time required for all the channels in each group of channels of the laser radar of the present invention to complete their work is implemented as Tteam32 x 1.4 x 44.8 us. And the group A channel and the group B channel in the laser radar start to work at the interval of the preset time T of 0.7us, so that the time required by all the channels in the laser radar to finish the work (namely, realizing one complete work cycle) is equal to the sum of the time required by all the channels in a single group and the preset time, namely Tround＝TteamAnd + t is 45.5 us. Thus, the laser radar completes the time T actually required by one working cycle through the multithreading staggered working mode of the inventionroundLess than the time T required for the laser radar to complete a cyclecycleTherefore, the multithreading staggered-time working mode adopted by the invention can obviously meet the time requirement of the laser radar on each working cycle.
It should be noted that, although the method for preventing inter-channel crosstalk for a lidar of the present invention employs a multi-thread time-staggered operation manner, which can greatly shorten the time required by the lidar to complete one working cycle, so as to meet the time requirement of the lidar on the working cycle, as shown in fig. 4A and 4B, a receiving channel in the channel a1 may still receive an echo signal B1 'corresponding to the channel B1 (i.e., a crosstalk signal B1' of the channel B1 to the channel a1) in addition to an echo signal a1 corresponding to itself (i.e., a true echo signal a1 of the channel a 1); meanwhile, the channel B1 can receive an echo signal B1 corresponding to the channel B1 (i.e., the real echo signal B1 of the channel B1), and also can receive an echo signal a2 'corresponding to the channel a2 (i.e., the crosstalk signal a 2' of the channel a2 to the channel B1).
However, since the channel a1 and the channel B1 start to operate respectively after the predetermined time t, and the channel B1 and the channel a2 also start to operate respectively after the predetermined time t, in the case that the distance of the detected object does not change much, as shown in fig. 4B, the time difference between the real echo signal a1 and the crosstalk signal B1 'of the channel a1 is substantially equal to the predetermined time t, and the time difference between the real echo signal B1 and the crosstalk signal a 2' of the channel B1 is also substantially equal to the predetermined time t; meanwhile, the time difference between the crosstalk signal B1' of the channel a1 and the real echo signal B1 of the channel B1 is substantially equal to zero, which is helpful for determining, by a software method, which of the echo signals received by the channel a1 are real echo signals and which are crosstalk signals, so that the crosstalk signals in the received echo signals are filtered out by the step S130 in the method for preventing inter-channel crosstalk for a laser radar of the present invention, so as to retain the real echo signals, thereby accurately calculating the flight time, which is beneficial for improving the detection accuracy of the laser radar. In other words, the method for preventing inter-channel crosstalk for the laser radar of the present invention can conveniently and accurately filter the crosstalk signal generated by inter-channel crosstalk only by a software method without changing the optical design of the laser radar.
Exemplarily, as shown in fig. 5, the step S130 of the method for preventing inter-channel crosstalk for lidar according to the first embodiment of the present invention further includes the steps of:
s131: monitoring the time and the intensity value of echo signals received by a receiving channel in all the channels;
s132: judging whether the time difference value between the echo signals received by the receiving channels in any two groups of channels is smaller than a time difference threshold value; if yes, using the corresponding echo signal as a suspected crosstalk signal pair;
s133: judging whether the intensity ratio between two echo signals in the suspected crosstalk signal pair is greater than an intensity ratio threshold value; if so, identifying the echo signal with the smaller intensity value as a crosstalk signal, and identifying the echo signal with the larger intensity value as a real echo signal; if not, determining the two echo signals in the suspected crosstalk signal pair as real echo signals; and
s134: and filtering the crosstalk signals to reserve the real echo signals.
Preferably, in an example of the present invention, the time difference threshold of the present invention may be implemented to be between ± 8 ns. In other words, step S132 of the present invention mainly determines whether the channels that are monitored by software and operated in a time-staggered manner receive the echo signals at the same time, and if the time difference value of receiving the echo signals is smaller than the time difference threshold, it is determined that the channels that are operated in a time-staggered manner receive the echo signals at the same time, so as to serve as suspected crosstalk signals (indicating that the echo signals may be crosstalk signals), and it is necessary to perform subsequent strength ratio determination on the suspected crosstalk signals, so as to finally determine whether the channels are crosstalk signals.
It is noted that, in the step S133 of the present invention, the intensity ratio threshold may be, but is not limited to, implemented as an intrinsic echo intensity ratio of the lidar in the presence of inter-channel crosstalk, wherein the intrinsic echo intensity ratio may be obtained by calibration in advance. Preferably, the intensity ratio threshold of the present invention is between 3 and 4.
In addition, for the multi-thread time-staggered operation mode shown in fig. 4A and 4B, the inter-channel crosstalk generally occurs from the first half period of the current channel to the second half period of the previous channel, but does not occur from the second half period of the current channel to the first half period of the next channel, because the echo signal in the second half period of the current channel is weak in intensity due to the long distance, and the generated crosstalk signal can be almost ignored. Therefore, when the method for preventing the inter-channel crosstalk for the laser radar filters and judges the crosstalk signals, only the fact that whether two echo signals are received at the same time or not and whether the amplitudes of the two echo signals accord with a certain proportion or not is judged, so that the real echo signals can be reserved to a great extent, and the risk that the real echo signals are filtered by mistake is greatly reduced.
It is worth mentioning that there may be some channels in the lidar that have no crosstalk with each other, so that these channels in the lidar can directly perform multi-threading simultaneous operation without the problem of crosstalk between channels. Compared with multi-thread time-staggered work, the multi-thread simultaneous work can further simplify the control procedure of the laser radar and reduce the calculated amount of the laser radar. Therefore, in order to fully combine the advantages of the multi-thread simultaneous operation mode and the multi-thread staggered operation mode and overcome the respective disadvantages, the second embodiment of the invention further provides a method for preventing crosstalk between channels for the laser radar.
Specifically, as shown in fig. 6, the method for preventing inter-channel crosstalk for lidar according to the second embodiment of the present invention includes the steps of:
s210: testing the crosstalk condition of each channel in the laser radar to other channels to obtain a mutual crosstalk-free channel group and a residual channel group;
s220: controlling the channels in the mutual non-crosstalk channel group to carry out simultaneous multi-thread work; and
s230: and controlling the channels in the remaining channel groups to carry out multithreading staggered-time work so as to filter crosstalk signals and keep real echo signals.
It is noted that, in an example of the present invention, as shown in fig. 7, the step S210 of the method for preventing inter-channel crosstalk for lidar includes the steps of:
s211: sequentially controlling the transmitting channels of the channels in the laser radar to independently perform transmitting work;
s212: determining whether receiving channels of all the channels in the laser radar receive echo signals or not and recording the echo signals; and
s213: judging whether crosstalk exists between different channels, and if not, dividing the corresponding channels into the mutual crosstalk-free channel groups; and if so, dividing the corresponding channel into the residual channel group.
It is to be noted that, in the step S213, the present invention preferably determines whether crosstalk exists between two channels, and if there is no crosstalk, it indicates that the two channels do not have the problem of crosstalk between channels when performing simultaneous operation, so that the two channels are divided into the mutually crosstalk-free channel group, so as to subsequently perform operation in a multi-thread simultaneous operation manner; if crosstalk exists, the problem of crosstalk between channels can occur when the two channels work simultaneously, so that the two channels are divided into the remaining channel group to work in a multi-thread staggered-time working mode in the subsequent process, so that crosstalk signals are filtered out through a software method, and real echo signals are reserved to the utmost extent.
Illustratively, the crosstalk conditions of all channels are tested according to the above method, and then screening is performed by comparing the crosstalk conditions of each channel, so that the channels which work simultaneously and do not crosstalk with each other are combined in pairs on hardware, and the screening principle is as follows: and selecting the channel as far as possible to satisfy the condition that each channel has a corresponding pairing channel, and the two paired channels do not have crosstalk. And enabling the selected two channels to work simultaneously according to the sequence. For example, the channels that can be operated simultaneously are divided into two groups, i.e., an upper group and a lower group, and the channels without crosstalk are selected from the two groups of channels to be paired for simultaneous operation. Of course, in other examples of the invention, if more than three channels are supported in hardware to operate simultaneously, the same approach is used to screen out the three crosstalk-free channels to operate simultaneously.
It should be noted that, in an example of the present invention, as shown in fig. 8, the step S220 of the method for preventing inter-channel crosstalk for lidar includes the steps of:
s221: grouping channels in the mutual non-crosstalk channel group to form n groups of channels, wherein n is more than or equal to 2; and
s222: and controlling the channels of different groups to start working at the same time so as to ensure that the channels of different groups which start working at the same time do not interfere with each other.
Further, in an example of the present invention, as shown in fig. 8, the step S220 further includes the steps of:
s223: and controlling the channels of the same group to perform single-thread time-sharing work so as to prevent the problem of inter-channel crosstalk between the channels of the same group.
According to the above embodiment of the present invention, the step S230 of the method for preventing inter-channel crosstalk for lidar includes the steps of:
grouping the channels in the rest channel groups to form N groups of channels, wherein N is more than or equal to 2;
controlling the channels of different groups to start working at intervals of preset time, wherein the preset time is not equal to positive integral multiple of the working time of a single channel; and
and processing the echo signals received by the receiving channels in all the channels to filter crosstalk signals in the echo signals received by each receiving channel and retain real echo signals.
According to another aspect of the present invention, there is further provided, according to the third embodiment of the present invention, a method for preventing inter-channel crosstalk for a lidar, which can combine advantages of a multi-thread simultaneous operation mode and a single-thread time-sharing operation mode to shorten a time required for each operation cycle of the lidar, and at the same time ensure that the lidar does not generate inter-channel crosstalk, which is beneficial to enabling the lidar to have higher detection accuracy.
Exemplarily, as shown in fig. 9, the method for preventing inter-channel crosstalk for lidar according to the above-described third embodiment of the present invention includes the steps of:
s310: testing the crosstalk condition of each channel in the laser radar to other channels to obtain a mutual crosstalk-free channel group and a residual channel group;
s320: controlling the channels in the mutual non-crosstalk channel group to carry out simultaneous multi-thread work; and
s330: and controlling the channels in the rest channel groups to perform single-thread time-sharing work so as to prevent signal crosstalk among the channels.
It should be noted that, in the third embodiment of the present invention, the step S320 adopts a multi-thread simultaneous operation manner for the channels in the mutually non-crosstalk channel group, so that the time required by the laser radar to complete one working cycle can be greatly shortened without signal crosstalk; in step S330, the channels in the remaining channel groups operate in a single-thread time-sharing manner to avoid signal crosstalk between the channels. It is understood that the single-thread time-sharing operation generally refers to: the method comprises the steps of firstly controlling a current channel to carry out transmitting and receiving work, and then controlling a next channel to carry out transmitting and receiving work after the current channel finishes all work, and the like, until all the channels finish corresponding work in sequence in a time-sharing manner, so that the problem of crosstalk among the channels cannot occur in the whole process.
Illustrative System
Referring to the description and shown in fig. 10, a system for preventing inter-channel crosstalk for a lidar according to an embodiment of the present invention is illustrated. Specifically, as shown in fig. 10, the system 1 for preventing inter-channel crosstalk for lidar includes a time-staggered working module 10, wherein the time-staggered working module 10 is used for communicably connecting the lidar, and the time-staggered working module 10 may include a channel grouping module 11, a time-staggered control module 12, and a echo signal processing module 13, which are communicably connected in sequence. The channel grouping module 11 is used for grouping a plurality of channels in the laser radar to form N groups of channels, wherein N is larger than or equal to 2. The timing error control module 12 is configured to control the channels in different groups to start operating at a predetermined time interval, where the predetermined time is not equal to a positive integer multiple of the operating time of a single channel. The echo signal processing module 13 is configured to process the echo signals received by the receiving channels of the multiple channels, so as to filter crosstalk signals in the echo signals, and retain real echo signals, so that the multiple channels in the laser radar complete multithreading staggered-time operation.
Further, in an example of the present invention, as shown in fig. 10, the echo signal processing module 13 may include a monitoring module 131, a time difference determining module 132, an intensity ratio determining module 133, and a filtering module 134, which are sequentially connected in a communication manner, wherein the monitoring module 131 is configured to monitor a time and an intensity value of the echo signal received through the receiving channel of all the channels; the time difference determining module 132 is configured to determine whether a time difference between the echo signals received by the receiving channels in any two groups of channels is smaller than a time difference threshold, and if so, take the corresponding echo signal as a suspected crosstalk signal pair; the intensity ratio determining module 133 is configured to determine whether an intensity ratio between two echo signals in the suspected crosstalk signal pair is greater than an intensity ratio threshold, and if so, regard the echo signal with a smaller intensity value as a crosstalk signal, and regard the echo signal with a larger intensity value as a real echo signal; if not, determining the two echo signals in the suspected crosstalk signal pair as real echo signals; wherein the filtering module 134 is configured to filter the crosstalk signal to retain the real echo signal.
It should be noted that, in the above embodiment of the present invention, as shown in fig. 10, the system 1 for preventing inter-channel crosstalk for lidar may further include a crosstalk testing module 20 and a simultaneous operation module 30, where the crosstalk testing module 20 is configured to test crosstalk of each channel in the lidar to other channels to obtain a mutually non-crosstalk channel group and a remaining channel group; wherein the simultaneous working module 30 is configured to control channels in the mutually non-crosstalking channel group to perform multi-thread simultaneous working. In particular, the time-staggered work module 10 may be further configured to control the channels in the remaining channel group to perform multi-thread time-staggered work.
In an example of the present invention, as shown in fig. 10, the crosstalk testing module 20 preferably includes a sequential control module 21, an echo signal determination module 22, and a crosstalk judgment module 23, which are sequentially and communicably connected, where the sequential control module 21 is configured to sequentially control the transmitting channel of each channel in the laser radar to perform transmitting operation individually; the echo signal determination module 22 is configured to determine whether the receiving channels of all the channels in the laser radar receive echo signals and record the echo signals; the crosstalk determining module 23 is configured to determine whether crosstalk exists between different channels, and if not, assign the corresponding channel into the channel group without crosstalk; and if so, dividing the corresponding channel into the residual channel group.
In an example of the present invention, the simultaneous working module 30 may be further configured to group channels in the mutually non-crosstalk channel group to form N groups of channels, where N ≧ 2; and controlling the channels of different groups to start working at the same time, and ensuring that no crosstalk exists between the channels of different groups working at the same time.
It should be noted that, in the above embodiment of the present invention, as shown in fig. 10, the system 1 for preventing inter-channel crosstalk for lidar may further include a time-sharing operation module 40, where the time-sharing operation module 40 is configured to control channels of the same group to perform single-thread time-sharing operation, so as to prevent the inter-channel crosstalk problem.
Of course, in an example of the present invention, the time-sharing operation module 40 may also be configured to control the channels in the remaining channel group to perform single-thread time-sharing operation, so as to prevent signal crosstalk between the channels.
Illustrative electronic device
An electronic device according to an embodiment of the invention is described below with reference to fig. 11 (fig. 11 shows a block diagram of an electronic device according to an embodiment of the invention). As shown in fig. 11, the electronic device 50 includes one or more processors 51 and a memory 52.
The processor 51 may be a Central Processing Unit (CPU) or other form of processing unit having data processing capabilities and/or instruction execution capabilities, and may control other components in the electronic device 50 to perform desired functions.
The memory 52 may include one or more computer program products that may include various forms of computer-readable storage media, such as volatile memory and/or non-volatile memory. The volatile memory may include, for example, Random Access Memory (RAM), cache memory (cache), and/or the like. The non-volatile memory may include, for example, Read Only Memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer readable storage medium and executed by the processor 51 to implement the methods of the various embodiments of the invention described above and/or other desired functions.
In one example, the electronic device 50 may further include: an input device 53 and an output device 54, which are interconnected by a bus system and/or other form of connection mechanism (not shown).
The input device 53 may be, for example, a camera module or the like for capturing image data or video data.
The output device 54 may output various information including the classification result and the like to the outside. The output devices 54 may include, for example, a display, speakers, a printer, and a communication network and remote output devices connected thereto, among others.
Of course, for the sake of simplicity, only some of the components of the electronic device 50 related to the present invention are shown in fig. 11, and components such as a bus, an input/output interface, and the like are omitted. In addition, electronic device 50 may include any other suitable components, depending on the particular application.
Illustrative computing program product
In addition to the above-described methods and apparatus, embodiments of the present invention may also be a computer program product comprising computer program instructions that, when executed by a processor, cause the processor to perform the steps in the methods according to various embodiments of the present invention described in the "exemplary methods" section above of this specification.
The computer program product may write program code for carrying out operations for embodiments of the present invention in any combination of one or more programming languages, including an object oriented programming language such as Java, C + + or the like and conventional procedural programming languages, such as "r" or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device, or entirely on the remote computing device or server.
Furthermore, an embodiment of the present invention may also be a computer-readable storage medium having stored thereon computer program instructions, which, when executed by a processor, cause the processor to perform the steps of the above-described method of the present specification.
The computer readable storage medium may take any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may include, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.
The basic principles of the present invention have been described above with reference to specific embodiments, but it should be noted that the advantages, effects, etc. mentioned in the present invention are only examples and are not limiting, and the advantages, effects, etc. must not be considered to be possessed by various embodiments of the present invention. Furthermore, the foregoing disclosure of specific details is for the purpose of illustration and description and is not intended to be limiting, since the invention is not limited to the specific details described above.
The block diagrams of devices, apparatuses, systems involved in the present invention are only given as illustrative examples and are not intended to require or imply that the connections, arrangements, configurations, etc. must be made in the manner shown in the block diagrams. These devices, apparatuses, devices, systems may be connected, arranged, configured in any manner, as will be appreciated by those skilled in the art. Words such as "including," "comprising," "having," and the like are open-ended words that mean "including, but not limited to," and are used interchangeably therewith. The words "or" and "as used herein mean, and are used interchangeably with, the word" and/or, "unless the context clearly dictates otherwise. The word "such as" is used herein to mean, and is used interchangeably with, the phrase "such as but not limited to".
It should also be noted that in the apparatus, devices and methods of the present invention, the components or steps may be broken down and/or re-combined. These decompositions and/or recombinations are to be regarded as equivalents of the present invention.
The previous description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the invention. Thus, the present invention is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention. The objects of the invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and any variations or modifications of the embodiments of the present invention may be made without departing from the principles.
Claims (15)
1. A method for preventing cross talk between channels for a lidar comprising the steps of:
grouping a plurality of channels in the laser radar to form N groups of channels, wherein N is more than or equal to 2;
controlling the channels of different groups to start working at a preset time interval, wherein the preset time is not equal to the positive integral multiple of the working time of a single channel; and
and processing the echo signals received by the receiving channels in the plurality of channels to filter crosstalk signals in the echo signals, and reserving real echo signals for the plurality of channels in the laser radar to finish multi-thread time-staggered work.
2. The method of claim 1, wherein in the step of grouping the plurality of channels in the lidar, the plurality of channels are equally divided into N groups such that the number of channels in the different groups of channels is the same.
3. The method for lidar to prevent inter-channel crosstalk according to claim 2, wherein in the step of controlling the channels of different groups to start operating at a predetermined time interval, the predetermined time interval is equal to a ratio of an operating time of the single channel to the number of groups N.
4. The method for lidar against inter-channel crosstalk according to claim 3, wherein the step of processing the echo signal received through the receiving channel of the plurality of channels further comprises the steps of:
monitoring the time and the intensity value of the echo signal received by the receiving channel in all the channels;
judging whether the time difference value between the echo signals received by the receiving channels in any two groups of channels is smaller than a time difference threshold value, if so, taking the corresponding echo signals as suspected crosstalk signal pairs;
judging whether the intensity ratio between two echo signals in the suspected crosstalk signal pair is greater than an intensity ratio threshold value, if so, identifying the echo signal with a smaller intensity value as a crosstalk signal, and identifying the echo signal with a larger intensity value as a real echo signal; if not, determining the two echo signals in the suspected crosstalk signal pair as real echo signals; and
and filtering the crosstalk signal to reserve the real echo signal.
5. The method for lidar to prevent inter-channel crosstalk according to any one of claims 1 to 4, further comprising, before the step of grouping the plurality of channels in the lidar, the steps of:
testing the crosstalk condition of each channel in the laser radar to other channels to obtain a crosstalk-free channel group and a residual channel group;
controlling the channels in the mutual non-crosstalk channel group to carry out simultaneous multi-thread work; and
and controlling the channels in the remaining channel group to carry out multi-thread time-staggered work.
6. The method for preventing inter-channel crosstalk for lidar of claim 5, wherein the step of testing the crosstalk of each channel in the lidar to other channels to obtain a mutually crosstalk-free channel group and a remaining channel group comprises the steps of:
sequentially controlling a transmitting channel of the channel in the laser radar to independently perform transmitting work;
determining whether all receiving channels of the channel in the laser radar receive echo signals and recording the echo signals; and
and judging whether crosstalk exists between different channels, if not, dividing the corresponding channel into the mutually crosstalk-free channel group, and if so, dividing the corresponding channel into the remaining channel group.
7. The method for lidar to prevent inter-channel crosstalk according to claim 6, wherein the step of controlling channels in the mutually non-crosstalk channel group to perform simultaneous multi-threading operation comprises the steps of:
grouping channels in the mutual non-crosstalk channel group to form n groups of channels, wherein n is more than or equal to 2; and
and controlling the channels of different groups to start working at the same time so as to ensure that the channels of the different groups which start working at the same time do not interfere with each other.
8. The method for preventing inter-channel crosstalk for lidar of any one of claims 1 to 4, further comprising the steps of:
and controlling the channels of the same group to perform single-thread time-sharing work.
9. A method for preventing cross talk between channels for a lidar comprising the steps of:
testing the crosstalk condition of each channel in the laser radar to other channels to obtain a crosstalk-free channel group and a residual channel group;
controlling the channels in the mutual non-crosstalk channel group to carry out simultaneous multi-thread work; and
and controlling the channels in the rest channel groups to perform single-thread time-sharing work.
10. An inter-channel crosstalk prevention system for a lidar comprising:
a time-staggered working module, wherein the time-staggered working module is used for communicably connecting the laser radar, wherein the time-staggered working module comprises the following components in sequence communicably connected:
the channel grouping module is used for grouping a plurality of channels in the laser radar to form N groups of channels, wherein N is more than or equal to 2;
the time staggering control module is used for controlling the channels of different groups to start working at a preset time interval, wherein the preset time is not equal to the positive integral multiple of the working time of a single channel; and
and the echo signal processing module is used for processing the echo signals received by the receiving channels in the plurality of channels so as to filter crosstalk signals in the echo signals and reserve real echo signals for the plurality of channels in the laser radar to finish multi-thread time-staggered work.
11. The system for preventing inter-channel crosstalk for lidar of claim 10, wherein the echo signal processing module comprises a monitoring module, a time difference determining module, an intensity ratio determining module and a filtering module, which are sequentially communicably connected, wherein the monitoring module is configured to monitor a time and an intensity value of the echo signal received through the receiving channel of all the channels; the time difference judging module is used for judging whether the time difference value between the echo signals received by the receiving channels in any two groups of channels is smaller than a time difference threshold value, if so, the corresponding echo signals are used as suspected crosstalk signal pairs; the strength ratio judging module is used for judging whether the strength ratio between two echo signals in the suspected crosstalk signal pair is greater than a strength ratio threshold value, if so, the echo signal with the smaller strength value is regarded as the crosstalk signal, and the echo signal with the larger strength value is regarded as the real echo signal; if not, determining the two echo signals in the suspected crosstalk signal pair as real echo signals; the filtering module is used for filtering the crosstalk signal so as to reserve the real echo signal.
12. The system for preventing inter-channel crosstalk for lidar of claim 11, further comprising a crosstalk testing module and a simultaneous operation module communicatively connected to each other, wherein the crosstalk testing module is configured to test crosstalk of each channel in the lidar to other channels to obtain a mutually crosstalk-free channel group and a remaining channel group; the simultaneous working module is used for controlling the channels in the mutual crosstalk-free channel group to carry out simultaneous multi-thread working; the time-staggered working module is also used for controlling the channels in the rest channel group to carry out multi-thread time-staggered working.
13. The system for preventing inter-channel crosstalk for lidar of claim 12, wherein the crosstalk testing module comprises a sequential control module, an echo signal testing module and a crosstalk determining module, which are sequentially communicably connected, wherein the sequential control module is configured to sequentially control the transmitting channel of the channel in the lidar to perform transmitting operation independently; the echo signal testing module is used for determining whether all receiving channels of the channel in the laser radar receive echo signals and recording the echo signals; the crosstalk judging module is used for judging whether crosstalk exists between different channels, if not, the corresponding channel is divided into the mutual crosstalk-free channel group, and if so, the corresponding channel is divided into the residual channel group.
14. The system for preventing crosstalk between channels of lidar of any of claims 10-13, further comprising a time-sharing operation module, wherein the time-sharing operation module is configured to control channels of the same group to perform single-thread time-sharing operation.
15. An electronic device, comprising:
a processor for executing program instructions; and
a memory, wherein the memory is configured to hold program instructions executable by the processor to perform a method for inter-channel crosstalk prevention for lidar, wherein the method for inter-channel crosstalk prevention for lidar comprises the steps of:
grouping a plurality of channels in the laser radar to form N groups of channels, wherein N is more than or equal to 2;
controlling the channels of different groups to start working at a preset time interval, wherein the preset time is not equal to the positive integral multiple of the working time of a single channel; and
and processing the echo signals received by the receiving channels in the plurality of channels to filter crosstalk signals in the echo signals, and reserving real echo signals for the plurality of channels in the laser radar to finish multi-thread time-staggered work.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911103521.9A CN112799032A (en) | 2019-11-13 | 2019-11-13 | Method for preventing crosstalk between channels for laser radar, system and electronic equipment thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911103521.9A CN112799032A (en) | 2019-11-13 | 2019-11-13 | Method for preventing crosstalk between channels for laser radar, system and electronic equipment thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112799032A true CN112799032A (en) | 2021-05-14 |
Family
ID=75803419
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911103521.9A Pending CN112799032A (en) | 2019-11-13 | 2019-11-13 | Method for preventing crosstalk between channels for laser radar, system and electronic equipment thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112799032A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115754979A (en) * | 2023-01-05 | 2023-03-07 | 北京亮道智能汽车技术有限公司 | Laser radar control method and device, control chip and laser radar |
| CN117075128A (en) * | 2023-09-11 | 2023-11-17 | 深圳市速腾聚创科技有限公司 | Ranging method, ranging apparatus, electronic device, and computer-readable storage medium |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108717182A (en) * | 2018-05-02 | 2018-10-30 | 深圳市速腾聚创科技有限公司 | Laser radar anti-disturbance method and anti-interference laser radar |
| JP2019078602A (en) * | 2017-10-23 | 2019-05-23 | ミネベアミツミ株式会社 | Laser ranger |
| CN109901177A (en) * | 2017-12-07 | 2019-06-18 | 北京万集科技股份有限公司 | A kind of method and device of improving laser radar range finding ability |
| CN209167536U (en) * | 2018-10-19 | 2019-07-26 | 浙江舜宇智能光学技术有限公司 | Laser emission component and multi-line laser radar |
| CN110121658A (en) * | 2016-12-30 | 2019-08-13 | 帕诺森斯有限公司 | LIDAR system |
-
2019
- 2019-11-13 CN CN201911103521.9A patent/CN112799032A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110121658A (en) * | 2016-12-30 | 2019-08-13 | 帕诺森斯有限公司 | LIDAR system |
| JP2019078602A (en) * | 2017-10-23 | 2019-05-23 | ミネベアミツミ株式会社 | Laser ranger |
| CN109901177A (en) * | 2017-12-07 | 2019-06-18 | 北京万集科技股份有限公司 | A kind of method and device of improving laser radar range finding ability |
| CN108717182A (en) * | 2018-05-02 | 2018-10-30 | 深圳市速腾聚创科技有限公司 | Laser radar anti-disturbance method and anti-interference laser radar |
| CN209167536U (en) * | 2018-10-19 | 2019-07-26 | 浙江舜宇智能光学技术有限公司 | Laser emission component and multi-line laser radar |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115754979A (en) * | 2023-01-05 | 2023-03-07 | 北京亮道智能汽车技术有限公司 | Laser radar control method and device, control chip and laser radar |
| CN115754979B (en) * | 2023-01-05 | 2023-05-23 | 北京亮道智能汽车技术有限公司 | Laser radar control method and device, control chip and laser radar |
| CN117075128A (en) * | 2023-09-11 | 2023-11-17 | 深圳市速腾聚创科技有限公司 | Ranging method, ranging apparatus, electronic device, and computer-readable storage medium |
| CN117075128B (en) * | 2023-09-11 | 2024-04-09 | 深圳市速腾聚创科技有限公司 | Ranging method, ranging apparatus, electronic device, and computer-readable storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110780306A (en) | Anti-interference method for laser radar and laser radar | |
| JP5019117B2 (en) | Distance image generator | |
| CN112799032A (en) | Method for preventing crosstalk between channels for laser radar, system and electronic equipment thereof | |
| JP6975432B2 (en) | Distance measuring device and distance measuring method | |
| CN108802746B (en) | Anti-interference ranging method and device | |
| JP6874165B2 (en) | Operating methods and control units for LiDAR systems, LiDAR systems, and operating equipment. | |
| KR20220024177A (en) | Adaptive multi-pulse LIDAR system | |
| CN115993590A (en) | Laser radar performance detection method, related device and computer storage medium | |
| KR20220003588A (en) | Temporal jitter in LIDAR systems | |
| CN110764097B (en) | Anti-interference method and device for laser radar, laser radar and storage medium | |
| CN108897000B (en) | Crosstalk suppression method and device, electronic equipment and computer readable medium | |
| US11782155B2 (en) | Distance measurement device and distance measurement system | |
| CN109975821B (en) | Control method and device, time-of-flight assembly, storage medium and computer equipment | |
| CN114365007A (en) | Method for measuring distance to target | |
| JP2021516756A (en) | Distance measurement system, automation equipment, and distance measurement method | |
| JP2021056213A (en) | Method and device for distance measurement | |
| CN115902836A (en) | Laser radar control method and device, control chip and laser radar | |
| CN111524364B (en) | Parking space state detection method and system | |
| DE102007012624B3 (en) | Apparatus to generate a three-dimensional distance image eliminates or corrects measurement errors through false reflections and the like | |
| CN115825930A (en) | Anti-interference method and device for laser radar, storage medium and laser radar | |
| CN116148812A (en) | Method, device and storage medium for improving laser ranging capability of radar system | |
| CN116338643A (en) | Laser radar distance measurement method and laser radar | |
| CN113484927A (en) | Target detection method, system and computer readable storage medium | |
| KR20170142018A (en) | Apparatus, method and computer readable recording medium for detecting target object by using controllable ultrasonic wave | |
| CN112034478A (en) | Laser radar and ranging method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |