Research On Real-time Model Of Millimeter Wave Radar For Smart Vehicle Virtual Test

Intelligent vehicle have now become a research hotspot in academia and industry.According to relevant research conclusions,for L3 and above autonomous driving systems,virtual simulation testing is the main research and development method.As an important part of the virtual simulation test,the quality of the virtual sensor model determines the degree to which the simulation replaces the real vehicle test.Therefore,the research of high-precision sensor models is an important research direction in the field of intelligent vehicle,and it is of great significance to the research and development of intelligent vehicle products.Millimeter-wave radar is a sensor commonly used in intelligent vehicle,and its high-precision real-time modeling is a difficult point for sensor modeling.There are usually “white box” models based on physical characteristics and “black box” models based on statistical characteristics.However,because the "white box" model cannot meet the requirements of real-time calculation,the "black box" model cannot accurately reflect the physical characteristics of the sensor.The establishment of a millimeter-wave radar that can reflect certain physical characteristics and can be calculated in real time is the current research focus.In view of the above situation,this paper explores a real-time model of a millimeter wave radar sensor considering the target reflection intensity(RCS).This model can not only meet the real-time requirements of virtual test of intelligent vehicle,but also reflect certain physical characteristics.The main research contents of this article include the following aspects:First,the millimeter-wave radar model based on geometrical calculations.In this paper,a millimeter-wave radar model based on geometric figures is established.In order to accurately realize the occlusion calculation between target objects during the perception process,this paper uses the shadow volume algorithm to screen and judge the target's visibility;In order to achieve rapid application migration of test objects,the output format of the actual sensor is labeled in this article.After simulation test verification,the model can realize the detection of target objects in the simulation environment,and can achieve occlusion calculation between target objects,while also ensuring high computing efficiency.Second,visibility judgment model considering target reflection intensity(RCS).Aiming at the method of judging target visibility in existing sensor models based on graphics research,it cannot effectively reflect its physical characteristics.This paper introduces the method of judging target visibility by RCS target reflection intensity.Based on the ray angle calculation algorithm,the visible area information of the target object is obtained,and the ideal angle reflection intensity is calculated by the vector angle calculation method.Finally,based on the vector projection method,the actual target reflection intensity value is calculated based on the relative position between the target and the host vehicle,the azimuth angle,and the target's own heading angle.The correction of the visibility of the target object determined by the graphic method is realized,and the fidelity of the target perception by the model is improved.Third,the real vehicle test research on the target reflection intensity.A target vehicle reflection intensity test and test platform composed of ESR millimeter wave radar,data acquisition system,distance measurement system,and target vehicle were established;Verification and calibration of the test platform using standard measurement systems;The test platform was used to measure the influence of the target vehicle's geometry,space structure,heading angle,and reflection surface material on the reflection intensity of the millimeter wave radar.The influences of different reflecting surfaces,different heading angles,and different reflecting surface materials on the reflection intensity were obtained.Finally,the millimeter wave radar model based on RCS visibility judgment established in this paper is simulated and verified.The perceptual difference between the original millimeter-wave model based on geometrical cutting judgment and the millimeter-wave radar model based on RCS visibility judgment is compared and analyzed under certain working conditions,and the validity of the model is tested.