Object position detection method and laser radar

Abstract

The present invention relates to an object position detection method and a laser radar. The method includes: generating an outgoing light and dividing the outgoing light into an outgoing wave signal and a local oscillator signal; emitting the outgoing wave signal outward; receiving an echo signal reflected by a detected target and projecting it to a detector; projecting the local oscillator signal to the detector at a preset angle so that the local oscillator signal and the echo signal interfere with each other before reaching the detector to form an interference signal and then project it to the detector; obtaining a first light intensity parameter of the echo signal; obtaining a second light intensity parameter of the local oscillator signal; obtaining a third light intensity parameter of the interference signal; determining the angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter; and determining the azimuth information of the detected target according to the angle. The azimuth information of the detected target can be accurately determined by the above method.

Description

Technical Field

[0001] The present invention relates to the field of laser radar technology, and in particular to an object position detection method and a laser radar. Background Art

[0002] LiDAR is a system that emits laser beams to detect target distance information, speed and other characteristic quantities. It is widely used in the field of laser detection. According to the different ways in which the laser radar light source is emitted, LiDAR can be divided into scanning and non-scanning types. Whether scanning or non-scanning, in the process of detecting the distance information of an object through a laser beam, it is not possible to accurately obtain the azimuth information of the detection field of view, thus failing to meet the needs of some application scenarios and having low applicability. Summary of the invention

[0003] Based on this, it is necessary to provide an object position detection method and a laser radar to address the problem that traditional laser radars cannot accurately obtain the azimuth information of the detection field of view during the process of detecting object distance information through laser beams, thus being unable to meet the needs of some application scenarios and having low applicability.

[0004] A method for detecting an object position, comprising:

[0005] generating an outgoing light and dividing the outgoing light into an outgoing wave signal and a local oscillation signal;

[0006] Emits the outgoing wave signal outwardly;

[0007] Receive the echo signal reflected by the detected target and project it to the detector;

[0008] Projecting the local oscillator signal to the detector at a preset angle, wherein the local oscillator signal and the echo signal interfere with each other before reaching the detector to form an interference signal, and then projecting the interference signal to the detector;

[0009] Acquiring a first light intensity parameter of the echo signal;

[0010] Acquire a second light intensity parameter of the local oscillator signal;

[0011] Acquiring a third light intensity parameter of the interference signal;

[0012] determining an angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter; and

[0013] The orientation information of the detected target is determined according to the angle.

[0014] In one of the embodiments, the method further includes: calculating the distance of the detected target based on the reception time of the echo signal and the transmission time of the outgoing wave signal, or calculating the distance of the detected target based on the phase difference between the echo signal and the outgoing wave signal.

[0015] In one embodiment, in the step of determining the angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter to obtain the angle between the echo signal and the outgoing wave signal, the calculation is performed according to the following formula:

[0016]

[0017] Wherein, I1 is the first light intensity parameter; I2 is the second light intensity parameter; I is the third light intensity parameter, and α is the angle between the echo signal and the local oscillator signal.

[0018] In one of the embodiments, the output wave signal is an amplitude modulated continuous wave signal; the method further comprises: performing phase-locking preprocessing on the local oscillator signal and the output wave signal.

[0019] In one embodiment, the first light intensity parameter, the second light intensity parameter and the third light intensity parameter are detected by different detectors, or the first light intensity parameter, the second light intensity parameter and the third light intensity parameter are detected by the same detector.

[0020] In one of the embodiments, the step further includes dividing the detector surface into a first detection area and a second detection area;

[0021] The first detection area detects the local oscillator signal to obtain the second light intensity parameter, and the second detection area detects the echo signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter and the third light intensity parameter respectively.

[0022] In one embodiment, the first light intensity parameter and the detector detect the echo signal, the local oscillator signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter, the second light intensity parameter and the third light intensity parameter respectively.

[0023] A laser radar, comprising:

[0024] An emitter, for generating outgoing light;

[0025] An optical splitter, used for dividing the outgoing light into an outgoing wave signal and a local oscillator signal;

[0026] An emission optical system, used to emit the outgoing wave signal outward, and project the local oscillation signal outward toward the detector at a preset angle;

[0027] A receiving optical system, used for receiving the echo signal formed after being reflected by the detected target and projecting it to the detector;

[0028] An interference optical system, used for causing the local oscillator signal and the echo signal to interfere with each other before reaching the detector to form an interference signal, and then projecting the interference signal to the detector;

[0029] The detector is used to detect the echo signal, the local oscillator signal and the interference signal to obtain a first light intensity parameter of the echo signal, a second light intensity parameter of the local oscillator signal and a third light intensity parameter of the interference signal; and

[0030] A controller is connected to the detector and is used to determine the angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter, and to determine the azimuth information of the detected target according to the angle.

[0031] In one embodiment, the detector includes a first detection area and a second detection area; the first detection area detects the local oscillator signal to obtain the second light intensity parameter, and the second detection area detects the echo signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter and the third light intensity parameter respectively; or

[0032] The detector detects the echo signal, the local oscillator signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter, the second light intensity parameter and the third light intensity parameter respectively.

[0033] In one embodiment, the processor performs calculation according to the following formula:

[0034]

[0035] Wherein, I1 is the first light intensity parameter; I2 is the second light intensity parameter; I is the third light intensity parameter, and α is the angle between the echo signal and the local oscillator signal.

[0036] The above-mentioned object position detection method and laser radar divide the generated outgoing light into an outgoing wave signal and a local oscillator signal, and control the local oscillator signal to be projected to the detector at a preset angle, so that the local oscillator signal and the echo signal interfere with each other before reaching the detector to form an interference signal and then are projected to the detector. By measuring the third light intensity parameter of the interference signal, the second light intensity parameter of the local oscillator signal, and the first light intensity parameter of the echo signal, the angle between the local oscillator signal and the echo signal can be calculated, so that the angle between the outgoing wave signal and the echo signal can be determined, and finally the azimuth information of the detected target can be determined. In addition to determining the distance information, the above-mentioned method can also accurately determine the azimuth information of the detected target, thereby meeting the detection requirements of the orientation in different scenes, and has strong adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a flow chart of an object position detection method in one embodiment.

[0038] Figure 2 It is a schematic diagram of interference between a local oscillator signal and an echo signal in one embodiment.

[0039] Figure 3 4 is a structural block diagram of a laser radar in one embodiment. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0041] In the description of the present application, it should be understood that the terms "center", "lateral", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, it should be noted that when an element is referred to as being "formed on another element", it may be directly connected to the other element or there may be a centered element at the same time. When an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be a centered element at the same time. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element.

[0042] Figure 1 FIG. 1 is a flow chart of an object position detection method in an embodiment. The method can be used in a laser radar to detect the position of an object by generating an outgoing light. Figure 1 , the method comprises the following steps:

[0043] Step S110, generating outgoing light and dividing the outgoing light into an outgoing wave signal and a local oscillation signal.

[0044] The outgoing light is generated by the transmitter. In one embodiment, the outgoing light is a laser, and the laser can be generated by a laser. The laser can be a single laser or a laser group, so as to realize a multi-line scanning process. The wavelength or frequency of the generated laser can be set according to the distance to be measured, and is not limited to a specific wavelength. The generated laser can be divided into two paths by a spectroscope, one for the outgoing wave signal and the other for the local oscillator signal. That is, the outgoing wave signal and the local oscillator signal are generated by the same light source and have the same wavelength or frequency. However, since the outgoing wave signal is used to achieve measurement, a higher energy is required, and the local oscillator signal is only used to interfere with the echo signal, so a smaller energy can be used. Therefore, in this embodiment, the spectroscope divides the laser energy unequally, the outgoing wave signal has most of the energy, and the local oscillator signal has a small part of the energy. It can be understood that there is no strict distribution ratio between the energy distribution of the two, and it only needs to meet their respective usage requirements. In one embodiment, the laser radar is a FLASH laser radar (also known as a flash laser radar), and its laser, that is, the light source, can be pulsed or continuous. In addition, the emitted light of the light source is emitted to the entire detected field of view in the form of a planar array. By adopting a planar array light source, the emitted light can cover the entire detection field of view at one time without any scanning device, which can simplify the structure of the entire laser radar and reduce costs. In addition, there is no mechanical movement during the emission process, which can quickly record the entire scene and avoid various interferences caused by the movement of the target or laser radar during the scanning process.

[0045] Step S120, emitting the outgoing wave signal outward.

[0046] When controlling the emission of the outgoing wave signal, the control of the detected target can be achieved by controlling its detection field of view. The detected target can be a specific object to be detected or a certain spatial area to be detected. The detected target can be an independent single object, multiple objects or a part of an object. The outgoing wave signal can be reflected and collimated by the transmitting optical system and then projected to the detected target.

[0047] Step S130, receiving the echo signal reflected by the detected target and projecting it to the detector.

[0048] Since the laser will diverge to a certain extent after being emitted, the spot size irradiated to the detected target is larger than the spot size when emitted, and the outgoing wave signal will be reflected on the detected target, thereby forming an echo signal that is successfully received by the receiving optical system. The receiving optical system is used to receive the reflected echo signal, and after deflecting and focusing it to a certain extent, project the echo signal to the detector. In one embodiment, the receiving optical system may include a space circulator, etc. The receiving optical system can be designed according to specific needs. In this embodiment, if the echo signal does not interfere with the local oscillator signal before being received by the detector, it can be directly projected to the detector and detected by the detector.

[0049] Step S140 , projecting the local oscillator signal toward the detector at a preset angle, so that the local oscillator signal and the echo signal interfere with each other before reaching the detector to form an interference signal, and then projected to the detector.

[0050] In the process of projecting the local oscillator signal to the detector at a preset angle, its reference object can be the detector surface or other components in the laser radar. If other reference objects are used, the angle relationship with the detector surface needs to be converted. In this embodiment, the local oscillator signal is projected at a preset angle relative to the detector surface, and the preset angle is a fixed angle. The preset angle can be set as needed. In one embodiment, by projecting the local oscillator signal to the detector in a direction parallel to the outgoing wave signal, the situation when the outgoing wave signal and the echo signal interfere can be simulated, so that measurement is performed according to the interference result. In one embodiment, when the laser radar is a FLASH laser radar, the detector uses a pixel-level detector array, that is, the detector is a planar array. In one embodiment, the local oscillator signal can be controlled to be projected to the detector at intervals, that is, within a certain time period, the local oscillator signal will not reach the detector, that is, it will not interfere with the echo signal, so that only the echo signal can be projected to the detector and received by the detector, thereby realizing the acquisition of the first light intensity parameter of the echo signal. In a certain time period, the local oscillator signal can reach the detector, and interfere with the echo signal before reaching the detector, forming an interference signal that is projected to the detector, so that the detector can obtain the third light intensity parameter of the interference signal. That is, the detector detects the local oscillator signal and the interference signal in a time-division multiplexing manner, and obtains the first light intensity parameter and the third light intensity parameter respectively. In one embodiment, the local oscillator signal and the echo signal are emitted to the detector after completing the interference before the receiving surface of the detector. In other embodiments, the local oscillator signal and the echo signal can also complete the interference at a place far away from the receiving surface of the detector, and then emit the interference signal to the surface of the detector, and even deflect the interference signal through some reflectors and then emit it to the surface of the detector. That is, before the local oscillator signal or the echo signal is received by the detector, the interference can be completed at any position, not necessarily in front of the receiving surface of the detector.

[0051] Step S150, obtaining a first light intensity parameter of the echo signal.

[0052] The value of the first light intensity parameter is used to indicate the light intensity of the echo signal. In the present embodiment, the first light intensity parameter is a current parameter. The echo signal can be detected by the detector and converted into an electrical signal before output, and in the conversion process, the current is proportional to the light intensity, so the light intensity of the echo signal can be characterized by the current parameter. Step S150 can be performed before step S140, that is, the echo signal is detected before interference to obtain the first light intensity parameter used to characterize its light intensity. In another embodiment, the detector can also detect the echo signal and the interference signal in a time division multiplexing manner, that is, the local oscillator signal is controlled to be unable to reach the detector in a certain period of time, so as not to interfere with the echo signal. At this time, the detector can detect the echo signal, and the local oscillator signal can reach the detector in a certain period of time and interfere before reaching the detector, so that the detector can detect the intensity of the interference signal.

[0053] Step S160, obtaining a second light intensity parameter of the local oscillator signal.

[0054] Similarly, the second light intensity parameter can be a current parameter to characterize the strength of the local oscillator signal. The local oscillator signal can be detected by a separate detector, or a special detection area can be set on the detector to detect the strength of the local oscillator signal. Because for the detector, the strength and wave loss of the local oscillator signal are theoretically the same everywhere, so it is only necessary to test a small specific area on the detector and only load the local oscillator signal to obtain its strength.

[0055] Step S170, obtaining a third light intensity parameter of the interference signal detected by the detector.

[0056] After the echo signal and the local oscillator signal interfere, the generated interference signal can be detected by a detector to obtain a third light intensity parameter of the interference signal. Similarly, the third light intensity parameter is a current parameter, which is used to characterize the intensity of the interference signal.

[0057] In one embodiment, the first light intensity parameter, the second light intensity parameter and the third light intensity parameter are obtained by the same detector. Specifically, the detector detects the detection echo signal, the local oscillator signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter, the second light intensity parameter and the third light intensity parameter respectively.

[0058] Step S180, determining the angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter.

[0059] In one embodiment, the order of steps S150, 160 and 170 is not limited to this embodiment, and only needs to be performed before step S180. After the echo signal, the local oscillator signal and the interference signal are obtained, the angle between the local oscillator signal and the echo signal can be determined according to the correlation principle of interference.

[0060] Step S190, determining the orientation information of the detected target according to the determined angle.

[0061] Since the local oscillator signal is projected to the detector at a preset angle relative to the detector surface, that is, its incident angle is determined, and the exit angle of the exit wave signal is also fixed and known, the angular relationship between the local oscillator signal and the exit wave signal can be determined. Therefore, after determining the angle between the local oscillator signal and the echo signal, the angular relationship between the echo signal and the exit wave signal can be determined based on the angular relationship between the local oscillator signal and the exit wave signal, thereby determining the azimuth information of the detected target, and then obtaining the relative position of the corresponding point cloud in the entire field of view. It can be understood that when the local oscillator signal is projected to the detector at a preset angle relative to other reference objects, it is necessary to convert the angular relationship between the local oscillator signal and the detector surface based on the angular relationship between the reference object and the detector surface.

[0062] In this embodiment, since the local oscillator signal is projected to the detector in a direction parallel to the outgoing wave signal, that is, the angle is actually the angle between the echo signal and the outgoing wave signal. Therefore, the azimuth information of the detected target can be determined based on the angle. Since the direction of the outgoing wave signal is determined, the precise spatial angle information of the point cloud detected by the echo signal relative to the laser radar can be accurately determined based on the angle, that is, the position information relative to the laser radar system.

[0063] The above-mentioned object position detection method divides the generated outgoing light into an outgoing wave signal and a local oscillator signal, and controls the local oscillator signal to be projected to the detector at a preset angle, so that the local oscillator signal and the echo signal interfere with each other before reaching the detector to form an interference signal and then are projected to the detector. By measuring the third light intensity parameter of the interference signal, the second light intensity parameter of the local oscillator signal, and the first light intensity parameter of the echo signal, the angle between the local oscillator signal and the echo signal can be calculated, so that the angle between the outgoing wave signal and the echo signal can be determined, and finally the azimuth information of the detected target can be determined. The above-mentioned method can accurately determine the azimuth information of the detected target, thereby meeting the detection requirements of different scenarios for the azimuth, and has strong adaptability.

[0064] In traditional laser radar, whether it is a ranging system based on a single point, or a coherent laser radar with a specific scanning structure or based on array reception, due to factors such as system performance and complexity, the main information of concern is the distribution and distance information of the point cloud, and it is impossible to accurately obtain the precise angle information of the point cloud in a specific direction. And it is generally believed that the angle between the echo signal and the outgoing wave signal is close to 180 degrees, that is, it is almost in a parallel state, so it is impossible to achieve the measurement of its precise orientation through relevant principles. The above method can well realize the measurement of the small angle between the echo signal and the outgoing wave signal, thereby accurately realizing the measurement of the orientation information of each point cloud on the detected target relative to the laser radar, expanding the scope of application of the laser radar.

[0065] In one embodiment, the interference between the echo signal and the local oscillator signal at the receiving surface of the detector is shown as follows: Figure 2 At this time, the angle between the local oscillator signal and the echo signal can be calculated using the following formula:

[0066]

[0067] Wherein, I1 is the first light intensity parameter; I2 is the second light intensity parameter; I is the third light intensity parameter, and α is the angle between the echo signal and the local oscillator signal.

[0068] Therefore, according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter, the angle between the echo signal and the local oscillator signal can be calculated. If the local oscillator signal is parallel to the direction of the outgoing wave signal, then the angle is equivalent to the angle between the outgoing wave signal and the echo signal, so that the azimuth information of the point cloud corresponding to the echo signal relative to the laser radar and its relative azimuth or angle information in the field of view can be determined. Figure 2 , after different areas on the detected target reflect the outgoing wave signal, they will form echo signals with different deflections, so that the deflection angle (θ, φ) of each echo signal relative to the outgoing wave signal can be obtained according to the above method, so as to accurately obtain the orientation information of each point cloud. By obtaining accurate point cloud orientation information, this information can be used in the three-dimensional scene reproduction or modeling of the detected target.

[0069] In one embodiment, the distance of the detected target can also be calculated based on the reception time of the echo signal and the emission time of the outgoing wave signal, that is, the distance test of the detected target is completed by using the flight time algorithm. In other embodiments, the distance of the detected target can also be calculated based on the phase difference or frequency difference between the echo signal and the outgoing wave signal. The specific implementation of the above method is known to those skilled in the art, and will not be repeated here. That is, the object position detection method in this embodiment is not limited to a certain type of laser radar, but can be used in almost most laser radars, and has strong universality.

[0070] In one embodiment, the generated outgoing wave signal is an amplitude modulated continuous wave signal. In this case, the local oscillator signal and the outgoing wave signal need to be pre-processed for phase locking before interference, so as to ensure that the local oscillator signal and the echo signal can have a relatively ideal interference before reaching the detector.

[0071] In one embodiment, the first light intensity parameter, the second light intensity parameter and the third light intensity parameter can be detected by different detectors respectively, or can be detected by the same detector.

[0072] In one embodiment, the above method further includes the step of dividing the detector surface into a first detection area and a second detection area. At this time, the first detection area detects the local oscillator signal to obtain the second light intensity parameter. As for the local oscillator signal, for the detector, its intensity and wave vector are theoretically the same everywhere. It is only necessary to test a small specific area on the detector area and only load the local oscillator signal to obtain its intensity information, that is, the first detection area can have a smaller area. The second detection area can detect the echo signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter and the third light intensity parameter respectively. Specifically, the local oscillator signal is loaded within a specific time period, and the detector detects the interference signal at this time; the local oscillator signal is isolated within the next time period, and the detector detects the echo signal at this time.

[0073] The above object position detection method can detect the position information including the orientation information of each point cloud on the detected target, which is simple and easy. Only basic processing of the echo signal and the vibration signal is needed to calculate the angle distribution of the detected object corresponding to the corresponding echo signal in the entire field of view. Compared with the traditional FLASH laser radar, for example, the use of microlens arrays and large-area detection arrays to detect the distance and angle information of spatial objects, when the FLASH laser radar is used to scan the detection area, only the signal needs to be processed, and the high-performance single-chip (no large-scale array) detector array can be used to simultaneously resolve the spatial distance and spatial position angle information of the object. The resolution depends on the number of detector vibration arrays actually used and the size of the detection area. In order to realize the calibration of the echo signal scanning of the spatial position of the object in the horizontal and vertical directions in the detection field, the larger the scale of the detector array of the system, the higher the resolution of the spatial position information. When the system uses a linear frequency conversion laser source, the distance, speed, spatial position and image information of different areas in the detection field of view can be obtained in theory at the same time.

[0074] Figure 3 FIG. 1 is a structural block diagram of a laser radar in an embodiment. Figure 3The laser radar includes a transmitter 310, a spectrometer 320, a transmitting optical system 330, a receiving optical system 340, an interference optical system 350, a detector 360 and a controller 370.

[0075] The transmitter 310 is used to generate output light. In one embodiment, the output light is a laser, and the transmitter 310 is a laser. The laser can be a single laser or a laser group, so as to realize a multi-line scanning process. The wavelength or frequency of the generated laser can be set according to the distance to be measured, and is not limited to a specific wavelength. In one embodiment, the laser can be a linear frequency-converting laser, so as to realize a low-cost, high-precision, high-interference-resistant coherent FLASH laser radar with scanning distance measurement, speed measurement, imaging and spatial position resolution capabilities.

[0076] The optical splitter 320 is used to split the outgoing light into an outgoing wave signal and a local oscillator signal. That is, the outgoing wave signal and the local oscillator signal are generated by the same light source and have the same wavelength or frequency. However, since the outgoing wave signal is used to achieve measurement, it requires higher energy, while the local oscillator signal only needs to be used to interfere with the echo signal, so a smaller energy can be used. Therefore, in this embodiment, the optical splitter 320 divides the laser energy unequally, the outgoing wave signal has most of the energy, and the local oscillator signal has a small part of the energy.

[0077] The transmitting optical system 330 is used to emit the outgoing wave signal outward, and to project the local oscillator signal outward to the detector at a preset angle. When controlling the emission of the outgoing wave signal, the control of the detected target can be achieved by controlling its detection field of view. The detected target can be a specific object to be detected, or a certain spatial area to be detected. The detected target can be an independent single object, or multiple objects or a part of an object. In the process of projecting the local oscillator signal to the detector at a preset angle, its reference object can be the detector surface or other components in the laser radar. If other reference objects are used, it is necessary to convert the angle relationship with the detector surface. In this embodiment, the local oscillator signal is projected at a preset angle relative to the detector surface, and the preset angle is a fixed angle. The preset angle can be set as needed. In one embodiment, by projecting the local oscillator signal to the detector in a direction parallel to the outgoing wave signal, the situation when the outgoing wave signal and the echo signal interfere can be simulated, so that measurement can be performed based on the interference result.

[0078] The receiving optical system 340 is used to receive the echo signal reflected by the detected target in response to the outgoing wave signal and project it to the detector. Since the laser will diverge to a certain extent after being emitted, the spot size irradiated to the detected target is larger than the spot size when emitted, and the outgoing wave signal will be reflected on the detected target, thereby forming an echo signal that is successfully received by the receiving optical system 340. The receiving optical system 340 deflects and focuses the received echo signal to a certain extent and then projects the echo signal to the detector. In one embodiment, the receiving optical system 340 may include a space circulator, etc. The receiving optical system 340 may be designed according to specific needs. In this embodiment, if the echo signal does not interfere with the local oscillator signal before being received by the detector, it can be directly projected to the detector and detected by the detector.

[0079] The interference optical system 350 is used to make the local oscillator signal and the echo signal interfere with each other before reaching the detector to form an interference signal, and then project it to the detector. The detector 360 is used to detect the echo signal, the local oscillator signal and the interference signal, and obtain the first light intensity parameter of the echo signal, the second light intensity parameter of the local oscillator signal and the third light intensity parameter of the interference signal.

[0080] The controller 360 is connected to the detector 350 and is used to determine the angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter, and determine the azimuth information of the detected target according to the angle.

[0081] The above-mentioned laser radar divides the generated outgoing light into an outgoing wave signal and a local oscillator signal, and controls the local oscillator signal to be projected to the detector at a preset angle, so that the local oscillator signal and the echo signal interfere with each other before reaching the detector to form an interference signal and then are projected onto the detector surface. By measuring the third light intensity parameter of the interference signal, the second light intensity parameter of the local oscillator signal, and the first light intensity parameter of the echo signal, the angle between the local oscillator signal and the echo signal can be calculated, so that the angle between the outgoing wave signal and the echo signal can be determined, and finally the azimuth information of the detected target can be determined. The above-mentioned laser radar can accurately determine the azimuth information of the detected target, thereby meeting the detection requirements of different scenarios for the azimuth, and has strong adaptability.

[0082] The detector 350 includes a first detection area and a second detection area. The first detection area detects the local oscillator signal to obtain the second light intensity parameter. The controller 360 can detect the echo signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter and the third light intensity parameter respectively. Specifically, the local oscillator signal is loaded in a specific time, and the detector detects the probe signal at this time; the local oscillator signal is isolated in the next time period, and the detector detects the echo signal at this time.

[0083] In one embodiment, the detector 350 detects the detection echo signal, the local oscillator signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter, the second light intensity parameter and the third light intensity parameter respectively. In another embodiment, the detector 350 can be a detection group, so that different light intensity parameters can be obtained through different detector units.

[0084] In one embodiment, the processor 360 performs calculation according to the following formula:

[0085]

[0086] Wherein, I1 is the first light intensity parameter; I2 is the second light intensity parameter; I is the third light intensity parameter, and α is the angle between the echo signal and the local oscillator signal.

[0087] In one embodiment, the laser radar is a FLASH laser radar (also known as a flash laser radar), and its laser, that is, the light source, can be pulsed or continuous. In addition, the emitted light of the light source is emitted to the entire detected field of view in the form of a planar array. By adopting a planar array light source, the emitted light can cover the entire detection field of view at one time without any scanning device, which can simplify the structure of the entire laser radar and reduce costs. In addition, there is no mechanical movement in the emission process, and the entire scene can be recorded quickly, avoiding various interferences caused by the movement of the target or the laser radar during the scanning process.

[0088] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0089] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for detecting an object position, comprising: generating an outgoing light and dividing the outgoing light into an outgoing wave signal and a local oscillation signal; The outgoing wave signal is emitted outwards; Receive the echo signal reflected by the detected target and project it to the detector; The local oscillator signal is projected toward the detector at a preset angle, and the local oscillator signal and the echo signal interfere with each other before reaching the detector to form an interference signal, and then are projected toward the detector; Acquiring a first light intensity parameter of the echo signal; Acquire a second light intensity parameter of the local oscillator signal; Acquiring a third light intensity parameter of the interference signal; Determining an angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter; as well as Determining the orientation information of the detected target according to the angle; In the step of determining the angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter, calculation is performed according to the following formula: Wherein, I1 is the first light intensity parameter; I2 is the second light intensity parameter; I is the third light intensity parameter, and α is the angle between the echo signal and the local oscillator signal.

2. The method according to claim 1, characterized in that The method further includes: calculating the distance of the detected target according to the reception time of the echo signal and the transmission time of the outgoing wave signal, or calculating the distance of the detected target according to the phase difference between the echo signal and the outgoing wave signal.

3. The method according to claim 1, characterized in that The first light intensity parameter is a current parameter; the second light intensity parameter is a current parameter; and the third light intensity parameter is a current parameter.

4. The method according to claim 1, characterized in that: The output wave signal is an amplitude modulated continuous wave signal; the method further comprises: performing phase-locking preprocessing on the local oscillator signal and the output wave signal.

5. The method according to claim 1, characterized in that The first light intensity parameter, the second light intensity parameter and the third light intensity parameter are detected by different detectors, or the first light intensity parameter, the second light intensity parameter and the third light intensity parameter are detected by the same detector.

6. The method according to claim 5, characterized in that It also includes the step of dividing the detector surface into a first detection area and a second detection area; The first detection area detects the local oscillator signal to obtain the second light intensity parameter, and the second detection area detects the echo signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter and the third light intensity parameter respectively.

7. The method according to claim 5, characterized in that The detector detects the echo signal, the local oscillator signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter, the second light intensity parameter and the third light intensity parameter respectively.

8. A laser radar, characterized in that: The method for detecting the position of an object according to any one of claims 1 to 7 comprises: An emitter, for generating outgoing light; An optical splitter, used for dividing the outgoing light into an outgoing wave signal and a local oscillator signal; An emitting optical system, used to emit the outgoing wave signal outward and project the local oscillator signal toward the detector at a preset angle; A receiving optical system, used for receiving the echo signal formed after being reflected by the detected target and projecting it to the detector; An interference optical system, used for causing the local oscillator signal and the echo signal to interfere with each other before reaching the detector to form an interference signal, and then projecting the interference signal to the detector; The detector is used to detect the echo signal, the local oscillator signal and the interference signal to obtain a first light intensity parameter of the echo signal, a second light intensity parameter of the local oscillator signal and a third light intensity parameter of the interference signal; and A controller is connected to the detector and is used to determine the angle between the local oscillator signal and the echo signal according to the first light intensity parameter, the second light intensity parameter and the third light intensity parameter, and to determine the azimuth information of the detected target according to the angle.

9. The laser radar according to claim 8, characterized in that: The detector includes a first detection area and a second detection area; the first detection area detects the local oscillator signal to obtain the second light intensity parameter, and the second detection area detects the echo signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter and the third light intensity parameter respectively; or The detector detects the echo signal, the local oscillator signal and the interference signal in a time division multiplexing manner to obtain the first light intensity parameter, the second light intensity parameter and the third light intensity parameter respectively.

10. The laser radar according to claim 8, characterized in that: The controller performs calculations according to the following formula: Wherein, I1 is the first light intensity parameter; I2 is the second light intensity parameter; I is the third light intensity parameter, and α is the angle between the echo signal and the local oscillator signal.

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