阅读说明：本技术 一种工作在24GHz的车载毫米波雷达反射器及设置方法 (Vehicle-mounted millimeter wave radar reflector working at 24GHz and setting method ) 是由 周原 任彩琴 刘明山 刘清忆 王迎 于 2021-08-05 设计创作，主要内容包括：本发明公开了一种工作在24GHz的车载毫米波雷达反射器及设置方法,反射器的本体为龙伯透镜,其中在龙伯透镜表面远离入射电磁波的一侧的焦点处装配有金属反射板。金属反射板为铝板。龙伯透镜采用分层嵌套的方式制成,龙伯透镜内共分为十六层,龙伯透镜的直径为79.68mm。设置方法为：步骤一、确定反射器工作频段；步骤二、确定反射器半径RR的大小；步骤三、确定反射器分层数T及每层的厚度D；步骤四、确定反射器第一至第十六层的相对介电常数ε-(r)的值；步骤五、确定金属反射板部署在反射器上的位置；步骤六、确定反射器在车上的安装位置。有益效果：能够随时使用车载毫米波雷达测得与其他车辆之间的距离,保证出行过程中驾驶员的安全性。反射效率较高。(The invention discloses a vehicle-mounted millimeter wave radar reflector working at 24GHz and a setting method thereof. The metal reflecting plate is an aluminum plate. The luneberg lens is manufactured in a layered nesting mode, the inside of the luneberg lens is divided into sixteen layers, and the diameter of the luneberg lens is 79.68 mm. The setting method comprises the following steps: step one, determining a reflector working frequency band; step two, determining the radius RR of the reflector; step three, determining the layering number T of the reflector and the thickness D of each layer; step four, determining the relative dielectric constant epsilon of the first to sixteenth layers of the reflector r A value of (d); fifthly, determining the position of the metal reflecting plate on the reflector; and step six, determining the installation position of the reflector on the vehicle. Has the advantages that: can use the vehicle-mounted millimeter wave radar to measure the distance between the vehicle and other vehicles at any time, and ensureThe safety of the driver in the traveling process. The reflection efficiency is high.)

1. The utility model provides a work is at 24 GHz's on-vehicle millimeter wave radar reflector which characterized in that: the body of the reflector is a luneberg lens, wherein a metal reflector plate is fitted at the focal point of the luneberg lens surface on the side away from the incident electromagnetic wave.

2. A vehicle millimeter wave radar reflector operating at 24GHz according to claim 1, wherein: the metal reflecting plate is an aluminum plate.

3. A vehicle millimeter wave radar reflector operating at 24GHz according to claim 1, wherein: the luneberg lens is manufactured in a layered nesting mode, the inside of the luneberg lens is divided into sixteen layers, and the diameter of the luneberg lens is 79.68 mm.

4. A method for setting a vehicle-mounted millimeter wave radar reflector working at 24GHz is characterized by comprising the following steps: the method comprises the following steps:

step one, determining a reflector working frequency band: according to the standard, 24GHz is one working frequency band of the vehicle-mounted millimeter wave radar, so that the working frequency band of the vehicle-mounted millimeter wave radar reflector is positioned at 24 GHz;

step two, determining the size of the radius RR of the reflector: the radius of the vehicle-mounted millimeter wave radar reflector is required to be larger than 3 times of the wavelength of the received electromagnetic wave, the wavelength of the electromagnetic wave corresponding to the 24Ghz band is 12.5mm, and the radius RR of the reflector is larger than 12.5 multiplied by 3 which is 37.5mm, so that the radius RR of the vehicle-mounted passive electromagnetic wave reflector is set to be 39.84 mm;

step three, determining the layering number T of the reflector and the thickness D of each layer: the vehicle-mounted millimeter wave radar reflector is manufactured in a layered nested mode, the reflector is designed into sixteen concentric spherical shells, the first concentric spherical shell is closest to the spherical center, the first concentric spherical shell is arranged from the first concentric spherical shell to the sixteenth concentric spherical shell in sequence from the near to the far away from the spherical center, the distance between the adjacent concentric spherical shells is called a concentric layer, the first concentric spherical shell is called a first layer, the part between the first concentric spherical shell and the second concentric spherical shell is called a second layer, the part between the second concentric spherical shell and the third concentric spherical shell is called a third layer, and the rest is done in sequence until the sixteenth layer;

when the thickness of each layer of the reflector is less than one fifth of the operating wavelength of the received electromagnetic waves, the layered structure of the reflector does not influence the propagation characteristics of the electromagnetic waves in the reflector, and the thickness D of each layer of the reflector is less than 12.5/5-2.5 mm, so that the thickness D of each layer of the vehicle-mounted millimeter wave radar reflector is 2.49 mm;

the radius RR of the vehicle-mounted millimeter wave radar reflector is 39.84mm, the thickness D of each layer of the reflector is 2.49mm, and the size of the total number of layered layers T of the reflector is 39.84 ÷ 2.49 ÷ 16, so that the total number of layered layers of the vehicle-mounted millimeter wave radar reflector is set to sixteen layers;

step four, determining the relative dielectric constant epsilon of the first to sixteenth layers of the reflector_rThe value of (c): the vehicle-mounted millimeter wave radar reflector is formed by embedding sixteen layers, and RR/RR is divided into sixteen intervals in the radial direction, namely [0,1/16 ], [1/16,2/16 ], [15/16,1 ]]Where rr is the distance from a point inside the reflector to the center of the sphere, and each layer of the reflector is made of a material having a uniform relative dielectric constant, so that the relative dielectric constant ε of the first through sixteenth layers is determined by mean value fitting_rA value of (d);

relative dielectric constant ε of each layer_rThe values of (A) are as follows: the relative dielectric constant of the first layer is 1.998046875; the relative dielectric constant of the second layer is 1.990234375; the relative dielectric constant of the third layer is 1.974609375; the relative dielectric constant of the fourth layer is 1.951171875; the relative dielectric constant of the fifth layer is 1.919921875; the relative dielectric constant of the sixth layer is 1.880859375; the relative dielectric constant of the seventh layer is 1.833984375; the relative dielectric constant of the eighth layer is 1.779296875; the relative dielectric constant of the ninth layer is 1.716796875; the relative dielectric constant of the tenth layer is 1.646484375; the relative dielectric constant of the eleventh layer is 1.568359375; the relative dielectric constant of the twelfth layer is 1.482421875; the relative dielectric constant of the thirteenth layer is 1.388671875; the relative dielectric constant of the fourteenth layer is 1.287109375; the relative dielectric constant of the fifteenth layer is 1.177734375; the relative dielectric constant of the sixteenth layer is 1.060546875；

Step five, determining the position of the metal reflecting plate on the reflector: before the reflector is installed, a metal reflecting plate is required to be added on one side of the surface of the reflector, which is far away from incident electromagnetic waves, a plurality of focuses are arranged on the surface of the reflector, which is far away from the incident electromagnetic waves, the metal reflecting plate corresponding to the positions of the focuses is added at the focuses, the metal reflecting plate is added to form a radar reflector, the metal reflecting plate is assembled at the focuses of the reflector, and the included angle between the metal reflecting plate and the center of a sphere is 90 degrees;

step six, determining the installation position of the reflector on the vehicle: install the reflector at the rear of a vehicle one in the middle, each one in both sides of car, it is one in the middle at the locomotive that on-vehicle millimeter wave radar corresponds to, each one in both sides of car, the reflector of the on-vehicle millimeter wave radar transmission electromagnetic wave that is located the locomotive gives adjacent place ahead vehicle rear of a vehicle, the display screen is given with the distance information that measures to on-vehicle millimeter wave radar, make the driver can know at any time the interval between the vehicle of the place ahead at the vehicle in-process of going like this, the same reason, the on-vehicle millimeter wave radar that is located the automobile body both sides can transmit the reflector of electromagnetic wave for adjacent left and right sides vehicle, the display screen is given with the distance information that measures to on-vehicle millimeter wave radar, thus, can know the interval with the vehicle on every side at the vehicle in-process of going, reduce the emergence of traffic accident.

Technical Field

The invention relates to a reflector and a setting method, in particular to a vehicle-mounted millimeter wave radar reflector working at 24GHz and a setting method.

Background

At present, how to ensure the safety of people in the traveling process becomes a problem to be solved urgently. The vehicle-mounted millimeter wave radar well solves the problem. Radar detects a distance between a current position and a target using electromagnetic waves. The working principle of the radar is as follows: the radar transmits electromagnetic waves to irradiate a target object and receives the returned electromagnetic waves, so that information such as the distance, the direction and the height between the target and a current electromagnetic wave transmitting point can be obtained. According to the national standard, 24GHz and 77GHz are the working frequency bands of the vehicle-mounted millimeter wave radar, and the two frequencies do not generate large interference or influence on human bodies or other electronic equipment. Wherein, the 24GHz frequency band is suitable for short-range vehicle-mounted radar, and the 77GHz frequency band is suitable for long-range vehicle-mounted radar.

In general, although the reflector of the electromagnetic wave is almost everywhere visible, since the electromagnetic wave is diffusely reflected when it is irradiated on the surface of the object, the electromagnetic wave that can be reflected in the direction opposite to the incident electromagnetic wave and can be received by the on-vehicle millimeter wave radar is only a part but not all of the electromagnetic wave, and if in extreme weather, such as rain or snow, the reflected electromagnetic wave can be received by the on-vehicle millimeter wave radar less or not. Under such circumstances, there is a strong demand for a vehicle-mounted millimeter wave radar reflector having a very high efficiency of returning electromagnetic waves along the original path.

Common passive radar reflectors are mainly corner reflectors, dipole reflectors, spherical dielectric lenses, and the like. The spherical dielectric lens reflector is also called as a luneberg lens reflector, and a metal reflecting layer is coated on a hemispherical surface of the luneberg lens or a part of the surface of the luneberg lens, so that the purpose of reflecting electromagnetic waves is achieved. At present, relevant documents are not found, and a dielectric lens reflector is mounted on a vehicle to assist the vehicle-mounted millimeter wave radar to communicate, so that the safety of the vehicle in the driving process can be better guaranteed.

In practical applicationDielectric lens reflectors are typically manufactured using a layered nesting method. An ideal luneberg lens is a spherically symmetric optical system consisting of an inhomogeneous medium with a relative dielectric constant that is graded from 1 to 2. The structure enables the luneberg lens to converge the incident plane wave to the other end perpendicular to the plane wave front diameter, so that the points on the spherical surface of the lens can be used as focal points. The refractive index and the relative dielectric constant n (r) of an ideal luneberg lens exhibit a continuous change from spherical to lens surface, wherein the change law of the relative dielectric constant n (r) is as follows:wherein r is_iIs the distance from a point in the sphere to the center of the sphere, and R is the lens radius.

Disclosure of Invention

The invention aims to provide a vehicle-mounted millimeter wave radar reflector working at 24GHz and a setting method thereof, which aim to enhance the strength of radar echo signals, facilitate other vehicles to detect a vehicle through a vehicle-mounted millimeter wave radar and ensure the safety of the vehicle in the driving process.

The body of the vehicle-mounted millimeter wave radar reflector working at 24GHz is a Luneberg lens, wherein a metal reflecting plate is assembled at a focus on one side of the surface of the Luneberg lens, which is far away from incident electromagnetic waves.

The metal reflecting plate is an aluminum plate.

The luneberg lens is manufactured in a layered nesting mode, the inside of the luneberg lens is divided into sixteen layers, and the diameter of the luneberg lens is 79.68 mm.

The luneberg lens is an assembly of existing equipment, and therefore specific models and specifications are not described in detail.

The invention provides a method for setting a vehicle-mounted millimeter wave radar reflector working at 24GHz, which comprises the following steps:

step one, determining a reflector working frequency band: according to the standard, 24GHz is one working frequency band of the vehicle-mounted millimeter wave radar, so that the working frequency band of the vehicle-mounted millimeter wave radar reflector is positioned at 24 GHz;

step two, determining the size of the radius RR of the reflector: the radius of the vehicle-mounted millimeter wave radar reflector is required to be larger than 3 times of the wavelength of the received electromagnetic wave, the wavelength of the electromagnetic wave corresponding to the 24Ghz band is 12.5mm, and the radius RR of the reflector is larger than 12.5 multiplied by 3 which is 37.5mm, so that the radius RR of the vehicle-mounted passive electromagnetic wave reflector is set to be 39.84 mm;

step three, determining the layering number T of the reflector and the thickness D of each layer: the vehicle-mounted millimeter wave radar reflector is manufactured in a layered nested mode, the reflector is designed into sixteen concentric spherical shells, the first concentric spherical shell is closest to the spherical center, the first concentric spherical shell is arranged from the first concentric spherical shell to the sixteenth concentric spherical shell in sequence from the near to the far away from the spherical center, the distance between the adjacent concentric spherical shells is called a concentric layer, the first concentric spherical shell is called a first layer, the part between the first concentric spherical shell and the second concentric spherical shell is called a second layer, the part between the second concentric spherical shell and the third concentric spherical shell is called a third layer, and the rest is done in sequence until the sixteenth layer;

when the thickness of each layer of the reflector is less than one fifth of the operating wavelength of the received electromagnetic waves, the layered structure of the reflector does not influence the propagation characteristics of the electromagnetic waves in the reflector, and the thickness D of each layer of the reflector is less than 12.5/5-2.5 mm, so that the thickness D of each layer of the vehicle-mounted millimeter wave radar reflector is 2.49 mm;

the radius RR of the vehicle-mounted millimeter wave radar reflector is 39.84mm, the thickness D of each layer of the reflector is 2.49mm, and the size of the total number of layered layers T of the reflector is 39.84 ÷ 2.49 ÷ 16, so that the total number of layered layers of the vehicle-mounted millimeter wave radar reflector is set to sixteen layers;

step four, determining the relative dielectric constant epsilon of the first to sixteenth layers of the reflector_rThe value of (c): the vehicle-mounted millimeter wave radar reflector is formed by embedding sixteen layers, and RR/RR is divided into sixteen intervals in the radial direction, namely [0,1/16 ], [1/16,2/16 ], [15/16,1 ]]Where rr is the distance from a point inside the reflector to the center of the sphere, and each layer of the reflector is made of a material having a relatively uniform dielectric constant, so that the mean value fitting is used to determine the first arrivalRelative dielectric constant ε of sixteen layers_rA value of (d);

relative dielectric constant ε of each layer_rThe values of (A) are as follows: the relative dielectric constant of the first layer is 1.998046875; the relative dielectric constant of the second layer is 1.990234375; the relative dielectric constant of the third layer is 1.974609375; the relative dielectric constant of the fourth layer is 1.951171875; the relative dielectric constant of the fifth layer is 1.919921875; the relative dielectric constant of the sixth layer is 1.880859375; the relative dielectric constant of the seventh layer is 1.833984375; the relative dielectric constant of the eighth layer is 1.779296875; the relative dielectric constant of the ninth layer is 1.716796875; the relative dielectric constant of the tenth layer is 1.646484375; the relative dielectric constant of the eleventh layer is 1.568359375; the relative dielectric constant of the twelfth layer is 1.482421875; the relative dielectric constant of the thirteenth layer is 1.388671875; the relative dielectric constant of the fourteenth layer is 1.287109375; the relative dielectric constant of the fifteenth layer is 1.177734375; the relative dielectric constant of the sixteenth layer is 1.060546875;

step five, determining the position of the metal reflecting plate on the reflector: before the reflector is installed, a metal reflecting plate is required to be added on one side of the surface of the reflector, which is far away from incident electromagnetic waves, a plurality of focuses are arranged on the surface of the reflector, which is far away from the incident electromagnetic waves, the metal reflecting plate corresponding to the positions of the focuses is added at the focuses, the metal reflecting plate is added to form a radar reflector, the metal reflecting plate is assembled at the focuses of the reflector, and the included angle between the metal reflecting plate and the center of a sphere is 90 degrees;

step six, determining the installation position of the reflector on the vehicle: install the reflector at the rear of a vehicle one in the middle, each one in both sides of car, it is one in the middle at the locomotive that on-vehicle millimeter wave radar corresponds to, each one in both sides of car, the reflector of the on-vehicle millimeter wave radar transmission electromagnetic wave that is located the locomotive gives adjacent place ahead vehicle rear of a vehicle, the display screen is given with the distance information that measures to on-vehicle millimeter wave radar, make the driver can know at any time the interval between the vehicle of the place ahead at the vehicle in-process of going like this, the same reason, the on-vehicle millimeter wave radar that is located the automobile body both sides can transmit the reflector of electromagnetic wave for adjacent left and right sides vehicle, the display screen is given with the distance information that measures to on-vehicle millimeter wave radar, thus, can know the interval with the vehicle on every side at the vehicle in-process of going, reduce the emergence of traffic accident.

The working principle of the invention is as follows:

the vehicle-mounted millimeter wave radar reflector working at 24Ghz and the setting method thereof provided by the invention adopt passive devices, and the radar reflection signals are enhanced by virtue of the total reflection characteristics of the radar reflector. The body of the vehicle-mounted millimeter wave radar reflector used in the invention is a Luneberg lens, and the working principle of the vehicle-mounted millimeter wave radar reflector is as follows: the vehicle-mounted millimeter wave radar sends electromagnetic waves to the reflector, the reflector gathers all received incident electromagnetic waves at one point on the surface of the reflector, the point is a focus, the metal reflecting plate is arranged at the focus and has a reflecting function, and the electromagnetic waves gathered to the focus are reflected back in the direction opposite to the direction of the incident electromagnetic waves, so that information is transmitted to the vehicle-mounted millimeter wave radar. The vehicle-mounted millimeter wave radar reflector provided by the invention can be used for measuring the distance between vehicles, so that a driver can measure the distance between the vehicle and the surrounding vehicles at any time in the driving process, the distance between the vehicle and the surrounding vehicles is dynamically adjusted, and the safety in the driving process is ensured.

In order to achieve the purpose, the vehicle-mounted millimeter wave radar reflector is manufactured by adopting a layered nesting method. The method mainly comprises the following steps: determining the structural size of a vehicle-mounted millimeter wave radar reflector; the number of layers to be layered; the thickness between each layer and the relative permittivity of each layer; a metal reflector plate is then added to the reflector surface on the side away from the incident electromagnetic wave. And finally, mounting the manufactured vehicle-mounted millimeter wave radar reflector on a vehicle.

The invention has the beneficial effects that:

the reflector in the vehicle-mounted millimeter wave radar reflector working at 24Ghz and the setting method provided by the invention has full-reverse characteristics in a horizontal plane, so that the reflection area of the radar is very large. This will be favorable to the vehicle no matter go on a journey under the weather condition of what, the homoenergetic uses on-vehicle millimeter wave radar to record and other vehicle between the distance at any time, guarantees the security of trip in-process driver. The reflector provided by the invention does not need energy input, is a passive device, and does not consume the energy of the automobile when being installed on the automobile. The diameter of the reflector provided by the invention is only 79.68mm, so that the reflector has small volume and light weight. The reflector provided by the invention is spherical and has full-reverse characteristics in a horizontal plane, so that the reflection efficiency is higher.

Drawings

Fig. 1 is a schematic view of the working principle of the vehicle-mounted passive electromagnetic wave reflector according to the present invention.

Fig. 2 is a schematic view of a manufacturing and installation process of the electromagnetic wave reflector according to the present invention.

Fig. 3 is a schematic cross-sectional view of a vehicle-mounted passive electromagnetic wave reflector according to the present invention.

Fig. 4 is a schematic diagram of the position of the metal reflector plate disposed on the reflector according to the present invention.

Fig. 5 is a schematic diagram of a position of the vehicle-mounted passive electromagnetic wave reflector of the present invention mounted on a vehicle.

The labels in the above figures are as follows:

1. the device comprises a Luneberg lens 2, a focus 3, a metal reflecting plate 4 and a vehicle-mounted millimeter wave radar.

Detailed Description

Please refer to fig. 1 to 5:

the body of the vehicle-mounted millimeter wave radar reflector working at 24GHz provided by the invention is a Luneberg lens 1, wherein a metal reflecting plate 3 is assembled at a focus 2 on one side of the surface of the Luneberg lens 1 far away from incident electromagnetic waves.

The metal reflection plate 3 is an aluminum plate.

The luneberg lens 1 is manufactured in a layered nesting mode, the inside of the luneberg lens 1 is divided into sixteen layers, and the diameter of the luneberg lens 1 is 79.68 mm.

The luneberg lens 1 is an assembly of existing equipment, and therefore specific models and specifications are not described in detail.

The invention provides a method for setting a vehicle-mounted millimeter wave radar reflector working at 24GHz, which comprises the following steps:

step one, determining a reflector working frequency band: according to the standard, 24GHz is one working frequency band of the vehicle-mounted millimeter wave radar 4, so that the working frequency band of the reflector of the vehicle-mounted millimeter wave radar 4 is positioned at 24 GHz;

step two, determining the size of the radius RR of the reflector: the radius of the reflector of the vehicle-mounted millimeter wave radar 4 is required to be larger than 3 times of the wavelength of the received electromagnetic wave, the wavelength of the electromagnetic wave corresponding to the 24Ghz band is 12.5mm, and the radius RR of the reflector is larger than 12.5 × 3 to 37.5mm, so the radius RR of the vehicle-mounted passive electromagnetic wave reflector is set to be 39.84 mm;

step three, determining the layering number T of the reflector and the thickness D of each layer: the vehicle-mounted millimeter wave radar 4 reflector is manufactured in a layered nested mode, the reflector is designed into sixteen concentric spherical shells, the first concentric spherical shell is closest to the spherical center, the first concentric spherical shell is arranged from the first concentric spherical shell to the sixteenth concentric spherical shell in sequence from the near to the far away from the spherical center, the distance between the adjacent concentric spherical shells is called a concentric layer, the first concentric spherical shell is called a first layer, the part between the first concentric spherical shell and the second concentric spherical shell is called a second layer, the part between the second concentric spherical shell and the third concentric spherical shell is called a third layer, and the rest is done in sequence until the sixteenth layer;

when the thickness of each layer of the reflector is less than one fifth of the operating wavelength of the received electromagnetic waves, the layered structure of the reflector does not influence the propagation characteristics of the electromagnetic waves in the reflector, and the thickness D of each layer of the reflector is less than 12.5/5-2.5 mm, so that the thickness D of each layer of the reflector of the vehicle-mounted millimeter wave radar 4 is set to be 2.49 mm;

the radius RR of the vehicle-mounted millimeter wave radar 4 reflector is 39.84mm, the thickness D of each layer of the reflector is 2.49mm, and the size of the total number of layered layers T of the reflector is 39.84 ÷ 2.49 ÷ 16, so that the total number of layered layers of the vehicle-mounted millimeter wave radar 4 reflector is set to sixteen layers;

step four, determining the relative dielectric constant epsilon of the first to sixteenth layers of the reflector_rThe value of (c): the vehicle-mounted millimeter wave radar 4 reflector is formed by embedding sixteen layers, and RR/RR are equal in radial directionSixteen intervals are divided, namely [0,1/16 ], [1/16,2/16 ], [15/16,1 ]]Where rr is the distance from a point inside the reflector to the center of the sphere, and each layer of the reflector is made of a material having a uniform relative dielectric constant, so that the relative dielectric constant ε of the first through sixteenth layers is determined by mean value fitting_rA value of (d);

relative dielectric constant ε of each layer_rThe values of (A) are as follows: the relative dielectric constant of the first layer is 1.998046875; the relative dielectric constant of the second layer is 1.990234375; the relative dielectric constant of the third layer is 1.974609375; the relative dielectric constant of the fourth layer is 1.951171875; the relative dielectric constant of the fifth layer is 1.919921875; the relative dielectric constant of the sixth layer is 1.880859375; the relative dielectric constant of the seventh layer is 1.833984375; the relative dielectric constant of the eighth layer is 1.779296875; the relative dielectric constant of the ninth layer is 1.716796875; the relative dielectric constant of the tenth layer is 1.646484375; the relative dielectric constant of the eleventh layer is 1.568359375; the relative dielectric constant of the twelfth layer is 1.482421875; the relative dielectric constant of the thirteenth layer is 1.388671875; the relative dielectric constant of the fourteenth layer is 1.287109375; the relative dielectric constant of the fifteenth layer is 1.177734375; the relative dielectric constant of the sixteenth layer is 1.060546875;

step five, determining the position of the metal reflecting plate 3 on the reflector: before the reflector is installed, a metal reflecting plate 3 is added on one side of the surface of the reflector, which is far away from incident electromagnetic waves, a plurality of focuses 2 are arranged on the surface of the reflector, which is far away from the incident electromagnetic waves, the metal reflecting plate 3 corresponding to the focuses 2 is added at the focuses 2, the metal reflecting plate 3 is added to form a radar reflector, the metal reflecting plate 3 is assembled at the focuses 2 of the reflector, and the included angle between the metal reflecting plate 3 and the center of a sphere is 90 degrees;

step six, determining the installation position of the reflector on the vehicle: install the reflector at the rear of a vehicle one in the middle, each one in both sides of car, it is one in the middle of the locomotive that on-vehicle millimeter wave radar 4 corresponds to, each one in both sides of car, the reflector of the on-vehicle millimeter wave radar 4 transmission electromagnetic wave for adjacent place ahead vehicle rear of a vehicle that is located the locomotive, on-vehicle millimeter wave radar 4 passes the distance information who measures to the display screen, make like this the driver can know the interval with the place ahead vehicle at any time at the vehicle in-process of going, and the like, on-vehicle millimeter wave radar 4 that is located the automobile body both sides can transmit the electromagnetic wave and give the reflector of adjacent left and right sides vehicle, on-vehicle millimeter wave radar 4 passes the distance information who measures to the display screen, like this, can know the interval with the vehicle on every side at the vehicle in-process of going, reduce the emergence of traffic accident.

The working principle of the invention is as follows:

the vehicle-mounted millimeter wave radar reflector working at 24Ghz and the setting method thereof provided by the invention adopt passive devices, and the radar reflection signals are enhanced by virtue of the total reflection characteristics of the radar reflector. The body of the vehicle-mounted millimeter wave radar 4 reflector used in the invention is a luneberg lens 1, and the working principle of the vehicle-mounted millimeter wave radar 4 reflector is as follows: the vehicle-mounted millimeter wave radar 4 sends electromagnetic waves to the reflector, the reflector gathers all received incident electromagnetic waves at one point on the surface of the reflector, the point is the focal point 2, the metal reflecting plate 3 is arranged at the focal point 2, and the metal reflecting plate 3 has a reflecting function, so that the electromagnetic waves gathered to the focal point 2 are reflected back in the direction opposite to the direction of the incident electromagnetic waves, and information is transmitted to the vehicle-mounted millimeter wave radar 4. The distance between the vehicle and the vehicle can be measured by utilizing the vehicle-mounted millimeter wave radar 4 reflector provided by the invention, so that a driver can measure the distance between the vehicle and the surrounding vehicle at any time in the driving process, the distance between the vehicle and the surrounding vehicle is dynamically adjusted, and the safety in the driving process is ensured.

In order to achieve the purpose, the vehicle-mounted millimeter wave radar 4 reflector is manufactured by adopting a layered nesting method. The method mainly comprises the following steps: determining the structural size of a vehicle-mounted millimeter wave radar 4 reflector; the number of layers to be layered; the thickness between each layer and the relative permittivity of each layer; a metal reflector plate 3 is then added to the reflector surface on the side away from the incident electromagnetic wave. And finally, mounting the manufactured vehicle-mounted millimeter wave radar 4 reflector on a vehicle.