Radar speed measurement calibration system and method

Abstract

The embodiment of the invention discloses a radar speed measurement calibration system and method. The radar speed measurement calibration system comprises a turntable, an orientation module, a radar and a processor, the turntable is used for rotating at a stable angular speed; the radar is used for transmitting a test signal to the side surface of the turntable in a rotating state and collecting the test signal reflected by the side surface of the turntable to obtain a reflected signal; the radar is arranged on the orientation module, and the orientation module is used for changing the signal emission position of the radar and ensuring that the emission direction of a test signal of the radar is always along the first direction; and the processor is used for determining the position of the reflection point of the test signal on the turntable, calculating the component velocity of the reflection point of the test signal on the turntable along the propagation direction of the test signal, and finally carrying out velocity calibration. According to the technical scheme of the embodiment of the invention, the problem that the drop point of the radar signal is difficult to find during speed calibration of the invisible light radar is solved, and accurate and rapid calibration of the radar speed measurement calibration system is realized.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of radar calibration technology, and in particular to a radar speed measurement calibration system and method. Background Art

[0002] Speed ​​calibration refers to the calibration of the radar system through a series of standard procedures and methods to ensure that it can accurately and reliably measure the speed of an object.

[0003] During the radar calibration process, since most radar speed measurement signals are invisible light, it is difficult to accurately determine the landing point of the radar signal, that is, the location of the target. In order to determine the landing point of the radar signal, geometric features in the environment are generally extracted and used to match the lidar point clouds. However, this method has high requirements for the site and is cumbersome to use. In addition, each time the radar to be calibrated is replaced, it needs to be re-matched. Summary of the invention

[0004] The present invention provides a radar speed measurement calibration system and method, which are used to solve the problem that invisible light radar cannot accurately and quickly determine the landing point of radar signals during speed calibration.

[0005] In a first aspect, an embodiment of the present invention provides a radar speed measurement calibration system, including a turntable, a directional module, a radar and a processor; the turntable is used to rotate at a stable angular velocity; the radar is used to transmit a test signal to the side of the rotating turntable, and collect the test signal reflected by the side of the turntable to obtain a reflected signal; the radar is arranged on the directional module, and the directional module is used to ensure that the transmission direction of the test signal of the radar is always along a first direction while changing the signal transmission position of the radar; the processor is used to determine the position of the reflection point of the test signal on the turntable; the processor is also used to calculate the component speed of the test signal at the reflection point on the turntable along the propagation direction of the test signal according to the position of the reflection point of the test signal on the turntable and the radius of the turntable; the processor is also used to perform speed calibration according to the component speed of the test signal at the reflection point on the turntable along the propagation direction of the test signal, the test signal and the reflected signal.

[0006] Optionally, the radar speed measurement calibration system also includes at least one signal receiver; the signal receiver is arranged on the side of the turntable, and is used to send a response signal to the processor when a test signal is received; the processor is also used to calculate the position of the reflection point of the test signal on the turntable based on the stable angular velocity of the turntable and the response signal.

[0007] Optionally, there are multiple signal receivers, and the multiple signal receivers are evenly distributed on the circumference formed by the side of the turntable.

[0008] Optionally, the radar speed measurement calibration system also includes a calibration light source module, which is used to emit auxiliary light; wherein the auxiliary light is parallel to the light of the test signal and there is a fixed position relationship in the propagation path; the processor is also used to calculate the position of the reflection point of the test signal on the turntable based on the landing point position of the auxiliary light and the fixed position relationship between the auxiliary light and the propagation path of the test signal.

[0009] Optionally, the calibration light source module includes a light source generator and a light source target; the light source generator is arranged on the directional module and has a fixed distance from the radar, and is used to emit auxiliary light; the light source target is arranged adjacent to the turntable, and is used to display the landing position of the auxiliary light.

[0010] Optionally, the calibration light source module also includes a fiber optic coupler and an output lens; the two input ends of the fiber optic coupler are optically connected to the radar and the light source generator through optical fibers, respectively, and the output end of the fiber optic coupler is provided with an output lens; the optical coupler is used to couple the test signal output by the radar and the auxiliary light output by the light source generator to form coupled light; the output lens is used to collimate the coupled light.

[0011] Optionally, the orientation module includes an orientation track, the radar is slidably set on the orientation track, the length of the orientation track is greater than or equal to the diameter of the turntable, and when a vertical line is drawn from any point on the turntable to the orientation track, the foot of the vertical line falls on the track.

[0012] In a second aspect, an embodiment of the present invention further provides a radar speed measurement calibration method, which is applied to a radar speed measurement calibration system such as the first aspect, the method comprising: determining the position of a reflection point of a test signal on a turntable; calculating the component speed of the test signal at the reflection point on the turntable along the propagation direction of the test signal based on the position of the reflection point of the test signal on the turntable and the radius of the turntable; and performing speed calibration based on the component speed of the test signal at the reflection point on the turntable along the propagation direction of the test signal, the test signal and the reflected signal.

[0013] Optionally, the radar speed measurement calibration system also includes at least one signal receiver; the signal receiver is arranged on the side of the turntable; determining the position of the reflection point of the test signal on the turntable includes: obtaining a response signal sent by the signal receiver when receiving the test signal; calculating the position of the reflection point of the test signal on the turntable based on the stable angular velocity of the turntable and the response signal.

[0014] Optionally, the radar speed measurement calibration system also includes a calibration light source module; determining the position of the reflection point of the test signal on the turntable includes: controlling the calibration light source module to emit auxiliary light; wherein the auxiliary light is parallel to the light of the test signal and there is a fixed position relationship in the propagation path; calculating the position of the reflection point of the test signal on the turntable based on the landing point position of the auxiliary light and the fixed position relationship between the auxiliary light and the propagation path of the light of the test signal.

[0015] The embodiment of the present invention provides a radar speed measurement calibration system, including a turntable, an directional module, a radar and a processor; the turntable rotates at a stable angular velocity, and the angular velocities of the test signal direction corresponding to different positions on the turntable are different, providing a target to be calibrated with multiple speeds; the radar transmits a test signal to the side of the turntable in a rotating state, and collects the test signal reflected by the side of the turntable to obtain a reflected signal, and the test signal and the reflected signal of the radar are used as data to be calibrated after simple mathematical processing; the radar is set on the directional module, and the directional module is used to ensure that the transmission direction of the radar test signal is always along a first direction while changing the signal transmission position of the radar Direction, the setting of the directional module ensures that the radar can send test signals to different positions on the turntable without changing the signal transmission direction; the processor determines the position of the reflection point of the test signal on the turntable; the processor also calculates the component speed of the reflection point of the test signal on the turntable along the propagation direction of the test signal according to the position of the reflection point of the test signal on the turntable and the radius of the turntable; the processor also performs speed calibration according to the component speed of the reflection point of the test signal on the turntable along the propagation direction of the test signal, the test signal and the reflected signal, and finally the processor calibrates the data to be calibrated with the component speed of the reflection point of the test signal on the turntable along the propagation direction of the test signal. The technical solution of the embodiment of the present invention solves the problem that it is difficult to find the landing point of the radar signal when the invisible light radar is calibrated, and realizes the accurate and fast calibration of the radar speed measurement calibration system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 1 is a schematic diagram of a top view structure of a radar speed measurement calibration system provided by an embodiment of the present invention;

[0017] Figure 2 It is a side view structural schematic diagram of a radar speed measurement calibration system provided by an embodiment of the present invention;

[0018] Figure 3 is a side view structural schematic diagram of another radar speed measurement calibration system provided by an embodiment of the present invention;

[0019] Figure 4 is a schematic diagram of a top view of another radar speed measurement calibration system provided by an embodiment of the present invention;

[0020] Figure 5 for Figure 4 The structural schematic diagram of the calibration light source module in the radar speed measurement calibration system shown;

[0021] Figure 6 It is a flow chart of a radar speed measurement calibration method provided by an embodiment of the present invention;

[0022] Figure 7It is a flow chart of another radar speed measurement calibration method provided by an embodiment of the present invention;

[0023] Figure 8 It is a flow chart of another radar speed measurement calibration method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention are shown in the accompanying drawings, rather than all structures.

[0025] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. It should be noted that the "upper", "lower", "left" and "right" directional words described in the embodiments of the present invention are described at the angles shown in the accompanying drawings and should not be understood as limitations on the embodiments of the present invention. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is formed "on" or "under" another element, it can not only be directly formed "on" or "under" another element, but also indirectly formed "on" or "under" another element through an intermediate element. The terms "first" and "second" are used for descriptive purposes only and do not indicate any order, quantity or importance, but are only used to distinguish different components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention are understood in specific circumstances.

[0026] The term “including” and its variations used in the present invention are open inclusions, that is, “including but not limited to.” The term “based on” means “based at least in part on.” The term “one embodiment” means “at least one embodiment.”

[0027] It should be noted that the concepts of “first” and “second” mentioned in the present invention are only used to distinguish the corresponding contents, and are not used to limit the order or interdependence.

[0028] It should be noted that the modifications of "one" and "plurality" mentioned in the present invention are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0029] Figure 1 is a schematic diagram of a top view of a radar speed measurement calibration system provided by an embodiment of the present invention, Figure 2 is a side view structural diagram of a radar speed measurement calibration system provided by an embodiment of the present invention, with reference to Figure 1 and Figure 2The embodiment of the present invention provides a radar speed measurement calibration system, including a turntable 10, an orientation module 11, a radar 12 and a processor 13; the turntable 10 is used to rotate at a stable angular velocity; the radar 12 is used to transmit a test signal to the side of the turntable 10 in a rotating state, and collect the test signal reflected by the side of the turntable 10 to obtain a reflected signal; the radar 12 is arranged on the orientation module 11, and the orientation module 11 is used to change the signal transmission position of the radar 12 while ensuring that the transmission direction of the test signal of the radar 12 is always along the first direction; the processor 13 is used to determine the position of the reflection point of the test signal on the turntable 10; the processor 13 is also used to calculate the component speed of the test signal at the reflection point on the turntable 10 along the propagation direction of the test signal according to the position of the reflection point of the test signal on the turntable 10 and the radius of the turntable 10; the processor 13 is also used to perform speed calibration according to the component speed of the test signal at the reflection point on the turntable 10 along the propagation direction of the test signal, the test signal and the reflected signal.

[0030] Among them, the turntable 10 can be understood as a rotating target with a certain thickness and can rotate stably; the stable speed can be understood as a preset adjustable speed to be measured. According to the measurement requirements, radar models, uses, etc., the stable speed can be adjusted and preset in the turntable. The first direction can be understood as a preset radar test direction. The selection of the first direction can be selected according to the measurement requirements, radar models, uses, etc., but the first direction cannot be changed during a complete calibration process. When the radar 12 sends a signal to the turntable along a fixed direction (such as along the first direction), the turntable speed component measured by it is always the speed component of this fixed direction (the speed component of the first direction). The directional module 11 can be understood as a device for changing the radar test position but not changing the measurement direction. The exemplary directional module can be composed of a slide rail and a directional carrier perpendicular to the first direction in the horizontal plane where the turntable is located. The radar is set on the directional carrier and always sends a test signal to the first direction. The radar 12 can be understood as a Doppler radar, which sends a test signal along a fixed direction and receives a reflected signal. The test signal can be understood as the original signal emitted by the Doppler radar, and the frequency fu of the signal is generally defined as the upstream frequency (Upstream Frequency) or the transmit frequency (Transmit Frequency). The reflected test signal, i.e., the reflected signal, can be understood as the frequency of the signal reflected from the moving target (such as the turntable 10) received by the radar, and the frequency fd of the signal is generally defined as the downstream frequency (Downstream Frequency) or the received frequency (Received Frequency). Due to the Doppler effect, the reflected frequency may be different from the original transmit frequency due to the movement of the target. The component velocity refers to the velocity component of an object in a specific direction. In this embodiment, the component velocity refers to the velocity component at different positions on the side of the turntable 10 in the propagation direction of the test signal.

[0031] Specifically, the radar 12 to be calibrated is set on the orientation module 11. When the orientation module 11 moves to the target position corresponding to the target position (different positions on the turntable 10) (the target position can be any projection position of the target position in the first direction), the test signal is sent to the target position to be calibrated in turn, and based on the received reflected signal and the test signal, the processor 12 obtains the velocity component of the target position along the direction of the test signal according to the diameter d of the turntable 10, the stable rotation speed and the position of the reflection point of the test signal on the turntable 10, and calibrates the velocity component as the actual velocity to the frequency difference between the reflected signal and the test signal.

[0032] It should be noted that the directional module 11 can transport the radar 12 to the target site by translation, rotation or any other method. The embodiment of the present invention does not limit the specific method. However, for ease of understanding, in the embodiment of the present invention, the directional module is displaced in a translational manner. The line between the target site and the target position should be parallel to the first direction. At the same time, in view of factors such as the range and accuracy of the radar, the target site needs to be set within the measurement range with relatively high radar range accuracy.

[0033] Exemplarily, assuming that the wavelength of the test signal is λ, the frequency of the test signal is fu, the frequency of the reflected signal is fd, the conversion coefficient is k, the fixed frequency deviation caused by the system is b, and the velocity component of the target position along the direction of the test signal is v1. The velocity calibration of the test signal, that is, the formula for calculating the conversion coefficient k is k=2*(v1-b) / [λ*(fu-fd)]. It should be understood that the velocity calibration process given here is only the simplest example for convenience of explanation and should not be interpreted as limiting the scope of protection.

[0034] Figure 3 FIG. 1 is a side view structural diagram of another radar speed measurement calibration system provided by an embodiment of the present invention. Figure 3 As shown, in an optional embodiment, the radar speed measurement calibration system further includes at least one signal receiver 14; the signal receiver 14 is arranged on the side of the turntable 10, and is used to send a response signal to the processor 13 when the test signal is received; the processor 13 is also used to calculate the position of the reflection point of the test signal on the turntable 10 according to the stable angular velocity of the turntable 10 and the response signal.

[0035] The response signal may be understood as a signal including the signal receiver number and the time when the signal receiver receives the test signal.

[0036] Specifically, when the radar 12 to be calibrated sends a test signal to the target position to be calibrated in turn, the signal receiver 14 on the turntable 10 will send a response signal including the signal receiver number (for example, when there is only one, the default number is 0, and the signal receiver number does not need to be considered) and the time when it receives the test signal to the processor 13. The processor 13 calculates the position of the signal receiver 14 on the turntable 10 at the moment t1 when the signal receiver 14 receives the test signal based on the stable rotation speed ω of the turntable, the time t0 when the turntable starts to rotate, and the time t1 when the signal receiver 14 receives the test signal.

[0037] Exemplarily, the angle θ that the turntable rotates from t0 to t1 can be calculated by the following formula: θ=ω*(t1-t0), and then the angle θ is divided by 2π and the remainder is taken to give the equivalent angle of the signal sensor in the range of 0 to 2π.

[0038] Optionally, there are multiple signal receivers 14 , and the multiple signal receivers 14 are evenly distributed on the circumference formed by the side of the turntable 10 .

[0039] Specifically, when the radar 12 to be calibrated sends a test signal to the target position to be calibrated in turn, any signal receiver 14 on the turntable 10 will send a response signal including the signal receiver number (such as 0, 1, 2 and 3) and the time when it receives the test signal to the processor 13. The processor 13 calculates the position of the signal receiver 14 on the turntable 10 at the moment t1 when the signal receiver 14 receives the test signal based on the stable rotation speed ω of the turntable, the number of the signal receiver, the time t0 when the turntable starts to rotate, and the time t1 when the signal receiver 14 receives the test signal.

[0040] For example, there are 4 signal receivers, the angle between each signal receiver is 0.5π, and the angle that the turntable rotates is the angle that the 0th signal receiver rotates. The angle θ that the turntable rotates from t0 to t1 can be calculated by the following formula: θ=ω*(t1-t0). At this time, if the signal receiver received is the first signal sensor, the actual angle that the first signal sensor rotates is θ1, θ1=θ+0.5π. Then divide the angle θ1 that the first signal sensor rotates by by 2π and take the remainder to give the equivalent angle that the first signal sensor rotates by in the range of 0 to 2π.

[0041] Figure 4 FIG. 1 is a schematic diagram of a top view of another radar speed measurement calibration system provided by an embodiment of the present invention. Figure 4 As shown, in an optional embodiment, the radar speed measurement calibration system also includes a calibration light source module 15, which is used to emit auxiliary light; wherein the auxiliary light is parallel to the light of the test signal and there is a fixed position relationship in the propagation path; the processor 13 is also used to calculate the position of the reflection point of the test signal on the turntable 10 according to the landing point position of the auxiliary light and the fixed position relationship between the auxiliary light and the propagation path of the test signal.

[0042] Among them, the calibration light source module 15 can be understood as a visible light source placed in parallel with the radar, and the propagation direction and landing point of the test signal can be indirectly obtained through the optical path of the visible light source.

[0043] Specifically, the calibration light source module 15 emits auxiliary light parallel to the test signal to ensure that there is a fixed positional relationship between the propagation paths of the two; the landing position of the auxiliary light is captured using a sensor or image recognition method; the processor 13 determines the reflection point position of the test signal on the turntable 10 through geometric calculation based on the landing position of the auxiliary light and the fixed positional relationship between the light rays.

[0044] like Figure 4 As shown, in an optional embodiment, the calibration light source module 15 includes a light source generator 151 and a light source target 152; the light source generator 151 is arranged on the directional module 11 and has a fixed distance from the radar 12, and is used to emit auxiliary light; the light source target 152 is arranged adjacent to the turntable 10, and is used to display the landing position of the auxiliary light.

[0045] Specifically, Figure 4 The light source generator 151 is arranged on the side of the directional module 11. When the auxiliary light falls on the turntable 10 or the light source target 152, the landing position of the test signal is confirmed according to the relative position relationship between the light source target 152 and the auxiliary light irradiation point.

[0046] Figure 5 for Figure 4 The schematic diagram of the structure of the calibration light source module in the radar speed measurement calibration system is shown in FIG. Figure 5 As shown, in an optional embodiment, the calibration light source module 15 also includes a fiber coupler 153 and an output lens 154; the two input ends of the fiber coupler 153 are optically connected to the radar 12 and the light source generator 151 through optical fibers, respectively, and the output end of the fiber coupler 153 is provided with an output lens 154; the optical coupler 153 is used to couple the test signal output by the radar 12 and the auxiliary light output by the light source generator 151 to form coupled light; the output lens 154 is used to collimate the coupled light.

[0047] Among them, the fiber coupler can be understood as a passive optical device, which is used to combine the auxiliary light and the test signal; the output lens can be understood as the transmitting end of the fiber coupler, which is used to collimate the coupled light and adjust the light to be parallel or overlapping with the propagation direction of the original test signal, so as to accurately control the direction of the test signal.

[0048] Specifically, the auxiliary light and the test signal enter the fiber coupler through the input port, and coupling occurs inside the coupler. The coupled light is collimated by the output lens, and the coupled light is adjusted to be parallel or overlapping with the original test signal light path. The landing position of the test signal is confirmed based on the relative position relationship between the light source target 152 and the irradiation point of the coupled light.

[0049] Optionally, the orientation module 11 includes an orientation track, and the radar 12 is slidably set on the orientation track. The length of the orientation track is greater than or equal to the diameter of the turntable 10. When a vertical line is drawn from any point on the turntable 10 to the orientation track, the foot of the vertical line falls on the track.

[0050] Specifically, the orientation module 11 includes an orientation track module, and the radar 12 is slidably arranged on the track. The orientation track is arranged along the second direction, and the second direction is perpendicular to the first direction in the rotation plane of the turntable 10. The length of the orientation track is designed to be greater than or equal to the diameter of the turntable 10, ensuring that the radar 12 slides on the orientation track and can cover all points on the turntable 10, so as to realize speed calibration at any position on the turntable 10. By ensuring that the track length is greater than or equal to the turntable diameter d, it is ensured that the radar can completely cover the turntable, thereby improving the comprehensiveness and accuracy of the speed calibration.

[0051] The present invention provides a radar speed measurement calibration system, including a turntable, a directional module, a radar and a processor. The turntable rotates at a stable angular velocity, and the angular velocities of the test signal direction corresponding to different positions on the turntable are different, providing a target to be calibrated with multiple speeds; the radar transmits a test signal to the side of the turntable in a rotating state, and collects the test signal reflected by the side of the turntable to obtain a reflection signal, and the test signal and the reflection signal of the radar are used as data to be calibrated after simple mathematical processing; the radar is set on the directional module, and the directional module drives the radar to translate to the target site along the second direction; the second direction is perpendicular to the transmission direction of the test signal, and the setting of the directional module ensures that the radar obtains the test signal sent to different positions on the turntable when the signal transmission direction remains unchanged. The calibration light source module or the signal receiver set on the turntable ensures that the processor can obtain the position of the reflection point of the test signal on the turntable; then, according to the position of the reflection point of the test signal on the turntable and the radius of the turntable, the component speed of the reflection point of the test signal on the turntable along the propagation direction of the test signal is calculated, and the speed of the test signal and the reflection signal is calibrated.

[0052] Based on the radar speed measurement calibration system of the above embodiment, an embodiment of the present invention further provides a radar speed measurement calibration method. Figure 6 FIG. 1 is a flow chart of a radar speed measurement calibration method provided by an embodiment of the present invention. Figure 6 As shown, the method includes:

[0053] S110, determining the position of the reflection point of the test signal on the turntable.

[0054] Specifically, the directional module drives the radar to move along the second direction to the target location; the second direction is perpendicular to the transmission direction of the test signal, and the target location on the moving path of the directional module corresponds to the position of the reflection point of the test signal on the turntable. The target location on the moving path of the directional module is the projection of the position of the reflection point of the test signal on the turntable on the moving path of the directional module.

[0055] S120, calculating the component velocity of the reflection point of the test signal on the turntable along the propagation direction of the test signal according to the position of the reflection point of the test signal on the turntable and the radius of the turntable.

[0056] Specifically, determine the turntable parameters: turntable radius r, turntable angular velocity ω, determine the position of the reflection point; calculate the angle between the line connecting the reflection point and the center of the circle and the incident direction of the test signal; use trigonometric functions to calculate the component velocity.

[0057] For example, Figure 1 As shown, the projection of the center of the circle on the moving path of the directional module is the origin (0,0), the projection of the reflection point on the turntable on the moving path of the directional module is (x,0), the angle between the position of the reflection point on the turntable and the line connecting the center of the circle and the test signal is α, the diameter of the turntable is d, the radius is r = d / 2, and the component speed of the reflection point on the turntable along the propagation direction of the test signal is

[0058] S130, performing speed calibration according to the component speed of the test signal at the reflection point of the test signal on the turntable along the propagation direction of the test signal, the test signal and the reflection signal.

[0059] Specifically, determine the frequency and wavelength of the transmitted signal, the frequency of the reflected signal, the component speed of the test signal at the reflection point on the turntable along the propagation direction of the test signal, etc., establish a theoretical speed calculation formula for the test signal, and calibrate the speed calculation formula by comparing the calibration results with the actual measurement results.

[0060] For example, Figure 1 As shown, assuming that the wavelength of the test signal is λ, the frequency of the test signal is fu, the frequency of the reflected signal is fd, the conversion coefficient is k, the fixed frequency deviation caused by the system is b, and the velocity component of the target position along the direction of the test signal is v1. The velocity calibration of the test signal, that is, the conversion coefficient k, is calculated as k = 2*(v1-b) / [λ*(fu-fd)].

[0061] The embodiment of the present invention obtains the target position of the directional module along the second direction, and the target position is the projection of the reflection point on the moving path of the directional module. Then, based on the turntable parameters (such as radius, angular velocity) and the position of the reflection point, the angle between the line connecting the reflection point and the center of the circle and the incident direction of the test signal is calculated, and the component speed of the reflection point along the propagation direction of the test signal is obtained using trigonometric functions. Finally, the relationship between the speed and the test signal and the reflected signal is established, and the accurate conversion between the test data and the speed is realized, which improves the problems of inaccurate speed measurement and complex calibration that may exist in the invisible light radar speed measurement method, and improves the accuracy and reliability of the speed measurement.

[0062] Figure 7It is a flow chart of another radar speed measurement calibration method provided by an embodiment of the present invention, which is refined or optimized based on the radar speed measurement calibration method of the above embodiment. Specifically, the radar speed measurement calibration system also includes at least one signal receiver; the signal receiver is arranged on the side of the turntable; determining the position of the reflection point of the test signal on the turntable includes: obtaining a response signal sent by the signal receiver when receiving the test signal; and calculating the position of the reflection point of the test signal on the turntable according to the stable angular velocity of the turntable and the response signal.

[0063] For details not yet provided in this embodiment, please refer to the previous embodiment.

[0064] like Figure 7 As shown, another radar speed measurement calibration method provided by an embodiment of the present invention includes the following steps:

[0065] S210. Acquire a response signal sent by the signal receiver when receiving the test signal.

[0066] Specifically, a response signal sent by the signal receiver when receiving the test signal is obtained, and the response signal includes the number of the signal receiver, the time t0 when the turntable starts to rotate, and the time t1 when the signal receiver receives the test signal.

[0067] S220: Calculate the position of the reflection point of the test signal on the turntable according to the stable angular velocity of the turntable and the response signal.

[0068] Specifically, the response signal includes the signal receiver's number, the time t0 when the turntable starts to rotate, and the time t1 when the signal receiver receives the test signal. The position of the signal receiver on the turntable at the time t1 when the signal receiver receives the test signal is calculated based on the turntable's stable angular velocity and the response signal.

[0069] For example, there are 4 signal receivers (such as numbered 0, 1, 2 and 3), the angle between each signal receiver is consistent, which is 0.5π, and the angle rotated by the turntable is the angle rotated by the 0th signal receiver. The angle θ rotated by the turntable from t0 to t1 can be calculated by the following formula: θ = ω * (t1-t0). At this time, if the signal receiver received is the first signal sensor, the angle θ1 actually rotated by the first signal sensor is θ + 0.5π. Then divide the angle θ1 rotated by the first signal sensor by 2π and take the remainder to give the equivalent angle of the angle rotated by the first signal sensor in the range of 0 to 2π.

[0070] S230. Calculate the component velocity of the reflection point of the test signal on the turntable along the propagation direction of the test signal according to the position of the reflection point of the test signal on the turntable and the radius of the turntable.

[0071] S240, performing speed calibration according to the component speed of the test signal at the reflection point of the test signal on the turntable along the propagation direction of the test signal, the test signal and the reflection signal.

[0072] The embodiment of the present invention arranges a signal receiver on a turntable, obtains the time when the signal receiver receives a test signal, and locates the component speed of the reflection point of the test signal on the turntable along the propagation direction of the test signal according to the rotation speed of the turntable, thereby solving the problem that the traditional method cannot accurately obtain the landing point of the test signal.

[0073] Figure 8 It is a flow chart of another radar speed measurement calibration method provided by an embodiment of the present invention, which is refined or optimized based on the radar speed measurement calibration method of the above embodiment. Specifically, the radar speed measurement calibration system also includes a calibration light source module; determining the position of the reflection point of the test signal on the turntable, including: controlling the calibration light source module to emit auxiliary light; wherein the auxiliary light is parallel to the light of the test signal and there is a fixed position relationship in the propagation path; according to the landing point position of the auxiliary light and the fixed position relationship between the auxiliary light and the propagation path of the light of the test signal, the position of the reflection point of the test signal on the turntable is calculated.

[0074] For details not yet provided in this embodiment, please refer to the previous embodiment.

[0075] like Figure 8 As shown, another radar speed measurement calibration method provided by an embodiment of the present invention includes the following steps:

[0076] S310, controlling the calibration light source module to emit auxiliary light; wherein the auxiliary light is parallel to the light of the test signal and the propagation path has a fixed position relationship.

[0077] Specifically, since the auxiliary light is parallel to the light of the test signal and the propagation paths have a fixed position relationship, the landing point of the auxiliary light and the reflection point of the test signal on the turntable have the same fixed position relationship.

[0078] S320, calculating the position of the reflection point of the test signal on the turntable according to the landing point position of the auxiliary light and the fixed position relationship between the auxiliary light and the propagation path of the light of the test signal.

[0079] Specifically, the calibration light source module emits auxiliary light parallel to the test signal to ensure that there is a fixed positional relationship between the propagation paths of the two; the landing point of the auxiliary light is captured by using a sensor or image recognition method; the processor determines the reflection point position of the test signal on the turntable through geometric calculation based on the landing point position of the auxiliary light and the fixed positional relationship between the light rays.

[0080] S330, calculating the component velocity of the reflection point of the test signal on the turntable along the propagation direction of the test signal according to the position of the reflection point of the test signal on the turntable and the radius of the turntable.

[0081] S340, performing speed calibration according to the component speed of the test signal at the reflection point of the test signal on the turntable along the propagation direction of the test signal, the test signal and the reflection signal.

[0082] The embodiment of the present invention indirectly obtains the landing point of the test signal by setting a calibration light source module to emit auxiliary light parallel to the test signal, capturing the landing point position of the auxiliary light. Furthermore, by setting an optical fiber coupler to couple the auxiliary light with the test signal, the landing point of the test signal is directly obtained, which solves the problem that the traditional method cannot accurately obtain the landing point of the test signal.

[0083] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, but also includes more effective embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A radar speed measurement calibration system, characterized in that: Includes turntable, directional module, radar and processor; The turntable is used to rotate at a stable angular velocity; The radar is used to transmit a test signal to the side of the rotating disk, and collect the test signal reflected by the side of the rotating disk to obtain a reflected signal; The radar is arranged on the directional module, and the directional module is used to ensure that the transmission direction of the test signal of the radar is always along the first direction while changing the signal transmission position of the radar; The processor is used to determine the position of the reflection point of the test signal on the turntable; The processor is further configured to calculate a component velocity of the reflection point of the test signal on the turntable along a propagation direction of the test signal according to a position of the reflection point of the test signal on the turntable and a radius of the turntable; The processor is also used to perform speed calibration according to the component speed of the test signal at the reflection point of the test signal on the turntable along the propagation direction of the test signal, the test signal and the reflection signal.

2. The radar speed measurement calibration system according to claim 1, characterized in that: Also includes at least one signal receiver; the signal receiver is disposed on the side of the turntable, and is used to send a response signal to the processor when receiving the test signal; The processor is further configured to calculate the position of a reflection point of the test signal on the turntable according to the stable angular velocity of the turntable and the response signal.

3. The radar speed measurement calibration system according to claim 2, characterized in that: There are multiple signal receivers, and the multiple signal receivers are evenly distributed on the circumference formed by the side of the turntable.

4. The radar speed measurement calibration system according to claim 1, characterized in that: It also includes a calibration light source module, which is used to emit auxiliary light; wherein the auxiliary light is parallel to the light of the test signal and has a fixed position relationship in the propagation path; The processor is further used to calculate the position of the reflection point of the test signal on the turntable according to the landing point position of the auxiliary light and the fixed position relationship between the auxiliary light and the propagation path of the light of the test signal.

5. The radar speed measurement calibration system according to claim 4, characterized in that: The calibration light source module includes a light source generator and a light source target; The light source generator is arranged on the directional module and has a fixed distance from the radar, and is used to emit the auxiliary light; The light source target is disposed adjacent to the turntable and is used to display the landing point position of the auxiliary light.

6. The radar speed measurement calibration system according to claim 4, characterized in that: The calibration light source module also includes a fiber coupler and an output lens; The two input ends of the optical fiber coupler are optically connected to the radar and the light source generator through optical fibers, respectively, and the output end of the optical fiber coupler is provided with the output lens; The optical coupler is used to couple the test signal output by the radar and the auxiliary light output by the light source generator to form coupled light; The output lens is used to collimate the coupled light.

7. The radar speed measurement calibration system according to claim 1, characterized in that: The orientation module includes an orientation track, the radar is slidably arranged on the orientation track, the length of the orientation track is greater than or equal to the diameter of the turntable, and when a vertical line is drawn from any point on the turntable to the orientation track, the foot of the vertical line falls on the track.

8. A radar speed measurement calibration method, characterized in that: Applied to the radar speed measurement calibration system according to any one of claims 1 to 7, the method comprises: Determine the position of the reflection point of the test signal on the turntable; Calculate the component velocity of the reflection point of the test signal on the turntable along the propagation direction of the test signal according to the position of the reflection point of the test signal on the turntable and the radius of the turntable; The speed is calibrated according to the component speed of the test signal at the reflection point on the turntable along the propagation direction of the test signal, the test signal and the reflection signal.

9. The radar speed measurement calibration method according to claim 8, characterized in that: The radar speed measurement calibration system further comprises at least one signal receiver; the signal receiver is arranged on the side of the turntable; Determining the position of the reflection point of the test signal on the turntable includes: Acquiring a response signal sent by the signal receiver when receiving the test signal; The position of the reflection point of the test signal on the turntable is calculated according to the stable angular velocity of the turntable and the response signal.

10. The radar speed measurement calibration method according to claim 8, characterized in that: The radar speed measurement calibration system also includes a calibration light source module; Determining the position of the reflection point of the test signal on the turntable includes: Controlling the calibration light source module to emit auxiliary light; wherein the auxiliary light is parallel to the light of the test signal and has a fixed position relationship in the propagation path; The position of the reflection point of the test signal on the turntable is calculated according to the landing point position of the auxiliary light and the fixed position relationship between the auxiliary light and the propagation path of the light of the test signal.

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