Minimizing radar transmission loss by coating vehicle components with an additional radar correction layer.

Abstract

The computer implementation method may include the steps of receiving measured radar transmission loss values ​​for a vehicle section having a coated surface over a frequency range, and generating a set of trial variables for a hypothetical section stack having expected signal (radar) transmission loss. The method may also include the steps of adjusting the trial variables for various hypothetical stacks until a hypothetical stack matching the actual measured values ​​is identified. The system may be further configured to perform various computational optimization routines to identify an appropriate radar correction layer that minimizes the actual transmission loss of the radar-transmitting section to an acceptable level.

Description

Technical Field

[0001] Cross - Reference to Related Applications This invention claims the benefit of priority to U.S. Provisional Application No. 63 / 501,739, filed on May 12, 2023, the entire content of which is incorporated herein by reference.

[0002] 1. Technical Field This disclosure relates to systems and methods for minimizing signal loss by an applied coating.

Background Art

[0003] 2. Background and Related Art The use of radar is becoming commonplace in modern transportation using a variety of autonomous or unmanned objects or vehicles such as passenger cars and land, water, or airborne drones. The use of radar is expected to increase as manufacturers further advance driver assistance systems. These types of vehicles generally use radar or other detection systems for driver detection systems such as adaptive cruise control, automatic braking, etc.

[0004] Driver assistance systems generally include various signal transmission components, such as signal transceivers and / or sensors, located on the outside of the vehicle or concealed within the vehicle's body, for identifying obstacles, pedestrians, other vehicles, weather, etc. Manufacturers generally optimize signal transmission components for maximum object detection capability. However, when a vehicle requires repainting (e.g., due to damage, fading), identifying the appropriate color is only part of the problem, as the new paint coating layer may adversely affect the signal transmission components. In particular, the performance of radar (or other signal transmission systems) can be hindered by the new coating layer positioned over the signal transmission components, i.e., the "radar-transmitting section" of a particular vehicle or object. Such factors may include signal loss due to changes in the dielectric constant and / or thickness of the coating layer. Signal transmission can also be adversely affected by several factors related to the various chemical compositions of layers, including fillers or pigments added for visual or texture effects.

[0005] Therefore, there are several considerations that can be addressed in this field of technology. [Overview of the project]

[0006] This disclosure provides systems, methods, and computer program products for modeling radar correction layers that enable newly coated objects to meet radar compliance requirements. For example, a user who wishes to coat an object can employ various modeling techniques to identify various transmission loss characteristics of the substrate (e.g., a transparent section of the object). The user can also model various assumed coating stacks to verify the expected coating arrangement around the object and predict the signal transmission loss through the assumed coating stack and transparent section of the object. The user can further model various radar correction layers that are likely to minimize the predicted signal transmission loss.

[0007] For example, a computer implementation of the present disclosure may include a receiving step in a computer system, which includes receiving radar transmission loss values ​​corresponding to radar transmission loss measurements of a radar-transparent section of an object, wherein the received radar transmission loss values ​​include measurements taken from radar signals passing through the radar-transparent section over a frequency range of 1 GHz to 300 GHz. The method may also include a generating step, which includes generating a plurality of trial variables in the form of dielectric constant values ​​and thickness values ​​corresponding to a hypothetical radar-transparent section, wherein the hypothetical radar-transparent section includes a hypothetical section stack having a set of associated radar transmission loss values ​​over a frequency range of 1 GHz to 300 GHz. In addition, the method may include a adjusting step, which includes adjusting one or more of the trial variables to create a set of predicted radar transmission loss values ​​passing through the hypothetical section stack over a frequency range of 1 GHz to 300 GHz, wherein the predicted radar transmission loss values ​​versus the measured radar transmission loss values ​​are within a root mean square error (RMSE) of less than 0.1 dB. Furthermore, this method may include the step of performing a computational optimization routine via a computer system to predict the characteristics of a radar correction layer using one or more tuned trial variables, such that the predicted radar correction layer reduces the predicted radar transmission loss of the assumed stack when added to the assumed section stack in order to meet radar compliance requirements. Also, this method may include the step of generating an output command for displaying the predicted radar correction layer to the end user.

[0008] Additional or alternative configurations include a system that may include a processor and a computer-readable storage medium, the computer-readable storage medium storing computer-readable instructions thereon, which, when executed, cause the system to receive radar transmission loss data over measurement frequencies of 1 to 300 GHz, such as 60 GHz and 90 GHz, for i) radar transmission sections of a physical object and ii) multiple arrangements of one or more calibration layers applied around the radar transmission sections, wherein the radar transmission section includes a substrate and one or more coating layers applied thereto, each calibration layer having the same dielectric constant value. The system may also be configured to generate a plurality of predicted transmission loss values ​​from a plurality of trial variables in the form of dielectric constant values ​​and thickness values, corresponding to a plurality of predicted transmission loss values ​​for i) a hypothetical section stack and ii) a hypothetical section stack combined with each of the arrangements of one or more calibration layers, wherein the hypothetical section stack includes a plurality of hypothetical coating layers applied to a hypothetical substrate of a hypothetical transmission section of a hypothetical object. In addition, the system can be configured to adjust one or more trial variables to produce calculated radar transmission loss values ​​for i) a hypothetical section stack and ii) each arrangement of one or more calibration layers and combinations of the hypothetical section stack at the measurement frequency, such that the calculated radar transmission loss value versus the received radar transmission loss value is within a root mean square error of less than 0.1 dB. Furthermore, the system can be configured to use the adjusted trial variables to perform a computational optimization routine via a computer system to predict the characteristics of the radar correction layer so that the predicted radar correction layer reduces the predicted radar transmission loss when added to the hypothetical section stack to meet radar compliance requirements. Moreover, the system can be configured to provide the output of the predicted radar correction layer to the end user.

[0009] Further configurations of the present disclosure include a computer implementation method for determining one set of more radar correction layers to address the radar transmission loss of a radar-transparent section of an object. For example, the method may include receiving radar transmission loss data over measurement frequencies from 1 to 300 GHz, such as 60 GHz and 90 GHz, for i) a radar-transparent section of a physical object and ii) multiple arrangements of one or more calibration layers applied around the radar-transparent section, wherein the radar-transparent section comprises a substrate and one or more coating layers applied thereto, and each calibration layer has the same dielectric constant value. The method may also include generating a plurality of predicted transmission loss values ​​from a plurality of trial variables in the form of dielectric constant values ​​and thickness values, corresponding to i) a hypothetical section stack and ii) a hypothetical section stack combined with each of the arrangements of one or more calibration layers, wherein the hypothetical section stack comprises a plurality of hypothetical coating layers applied to a hypothetical substrate of a hypothetical transparent section of a hypothetical object. In addition, this method may include a step of adjusting one or more trial variables to produce calculated radar transmission loss values ​​for i) a hypothetical section stack and ii) each arrangement of one or more calibration layers and combinations of the hypothetical section stacks at the measurement frequency, such that the calculated radar transmission loss value versus the received radar transmission loss value is within a root mean square error of less than 0.1 dB. Furthermore, this method may include a step of using the adjusted trial variables to perform a computational optimization routine via a computer system to predict the characteristics of the radar correction layer, such that the predicted radar correction layer reduces the predicted radar transmission loss when added to the hypothetical section stack to meet radar compliance requirements. Moreover, this method may include a step of providing the output of the predicted radar correction layer to the end user.

[0010] Additional features and advantages are described in the following description and may be partially evident from the description or learned through practice. These features and advantages may be realized and obtained by means and combinations specifically indicated in the appended claims and embodiments. These and other features may be more fully evident from the following description and the appended claims or may be learned through practice of the embodiments described below.

[0011] To describe the manner in which the above-mentioned and other advantages and features can be obtained, a more specific description of the above is given by referring to the specific embodiments illustrated in the accompanying drawings. With the understanding that these drawings are merely illustrative and therefore not intended to limit their scope, this disclosure will be described and explained in more specific and detail through the use of the accompanying drawings. [Brief explanation of the drawing]

[0012] [Figure 1A] This disclosure illustrates an environment in which a user receives a vehicle to be coated, scans the vehicle, and identifies an alternative coating. [Figure 1B] This disclosure illustrates an environment in which a user receives a vehicle to be coated, scans the vehicle, and identifies an alternative coating. [Figure 2A] This disclosure illustrates a graphic diagram of potential alignment for measuring radar transmission loss values ​​in coated vehicles. [Figure 2B] Figure 2A illustrates a more detailed schematic diagram of the alignment shown, which illustrates the cross-section of the layers in the section stack that can be measured for radar transmission loss values ​​according to this disclosure. [Figure 3] This disclosure provides an example of a graphical representation of the curve corresponding to the measured radar transmission loss over frequency. [Figure 4]This disclosure illustrates a block diagram of a system for modeling measured radar transmission loss data using a hypothetical coating stack and predicted signal transmission loss. [Figure 5] This disclosure provides an example of a graphical representation of measured radar transmission loss values ​​compared to simulated radar transmission loss values ​​for a matching assumed stack. [Figure 6] This disclosure illustrates a block diagram of a system for modeling a radar correction layer predicted to minimize the predicted radar transmission loss identified in Figure 4. [Figure 7] This disclosure illustrates graphs of simulated radar transmission loss values ​​for an object substrate, a hypothetical coating stack, and a radar correction layer. [Figure 8] This disclosure illustrates a block diagram for measuring radar transmission loss values, which includes one or more calibration layers applied to a radar transmission section. [Figure 9] This disclosure provides an example of a graph displaying the measured radar transmission loss values ​​over a range of calibration layer thicknesses. [Figure 10] This disclosure illustrates a block diagram of a simulation system that determines an assumed coating stack using data obtained from the system shown in Figure 8. [Figure 11] This disclosure illustrates a block diagram of a simulation system for finding a desired radar correction layer to satisfy the radar compliance requirements for the assumed stack determined in Figure 10. [Figure 12] This disclosure illustrates a graphical representation of simulated radar transmission loss values ​​based on the application of the determined radar correction layer. [Figure 13] This disclosure provides an example flowchart of a method for modeling a radar correction layer to meet radar compliance requirements. [Figure 14] This disclosure illustrates flowcharts of additional or alternative methods for modeling the radar correction layer to meet the radar compliance requirements. [Modes for carrying out the invention]

[0013] The present disclosure provides a system, method, and computer program product for modeling a radar correction layer that enables a newly coated object to meet radar compliance requirements. For example, a user desiring to coat an object can implement various modeling techniques to identify the various transmission loss characteristics of a substrate (e.g., a transmissive section of the object). The user can also model various hypothetical coating stacks to view the expected coating placement around the object and predict the signal transmission loss through the hypothetical coating stack and transmissive section of the object. The user can further model various radar correction layers that are likely to minimize the predicted signal transmission loss.

[0014] As a preliminary matter, as used herein, the definite articles "a" and "an" are understood to mean "at least one" or "one or more" wherever they appear, unless explicitly defined to mean only the singular form. Additionally, as a further explanation, the terms "module" or "component" when used in the context of a computer system, computer-implemented method, or corresponding structure and function, are understood as an abstraction of a generalized computer processing component that can be used in at least one embodiment of the present disclosure, and may be more or less than those illustrated and described, and may be suitable for a particular server and cloud operating environment. As used herein, "module" means computer-executable code that, when executed by one or more processors in a particular computer system, causes the particular computer system to perform a particular function. On the other hand, "component" means a passive set of instructions or data structures or records that can store, manage, and / or otherwise provide information processed through a particular module. However, those skilled in the art will understand that the distinction between different modules or components is at least partially arbitrary, and that modules or components can be combined and divided differently and still remain within the scope of the present disclosure. Thus, the description of a component as being a "module" or "component" is provided only for clarity and explanation, and should not be construed as indicating that any particular structure of computer-executable code and / or computer hardware is required unless expressly stated otherwise. In this specification, terms such as "component", "agent", "manager", "service", "engine", "virtual machine", etc. may also be used similarly.

[0015] As used herein, “coating stack” means one or more coating or paint layers, such as one or more primer layers, one or more base coat layers, and / or one or more top coat layers, or any combination thereof, and, as necessary, one or more applications of each such layer. In other words, “coating stack” may include one base coat layer, or one primer layer, or one primer layer and one or more base coat layers, and / or top coat layers, and / or other variations and combinations thereof. On the other hand, “section stack” means a substrate (e.g., a bumper, side panel, mirror housing, etc.) combined with a coating stack (e.g., any one or more of the aforementioned layers).

[0016] Where used further herein, the term “given section stack” (or “given stack”) means “given” values, which in the case of a real object are measured values, or specified values, proposed values, or assumed values ​​(rather than measured or calculated values) for a proposed set of comparisons, based on a known range of a given material or element. See, for example, Table 1. A given value represents a real-world value (e.g., whether measured or entered as an expected value when conducting a comparative test) that can be compared to the predicted radar transmission loss of an assumed section stack based on a calculated trial variable. In other words, a “given” section stack is essentially a reference comparison value, meaning a measured value for a real vehicle, or, in the case of a simulated real-world object, a selected value, proposed value, or specified value within a known range that is encountered or may be encountered in the real world. “Assumed” for the purposes of this disclosure, on the other hand, includes one or more calculated values ​​compared to “given.” Naturally, a "given section stack" based on manually entered or "suggested" values ​​to simulate real-world objects, rather than measured values, can also be broadly called an "assumed section stack," where "assumed" is synonymous with "simulated." In any case, "given" means a simulation of an existing object / system, or something that exists or is likely to be encountered in a real-world scenario.

[0017] On the other hand, “hypothetical coating stack” means a set of thickness and dielectric constant values ​​for one or more coating layers, calculated by the system (e.g., 400 in Figure 4) for a coating applied to an object, in at least one example. Similarly, “hypothetical transmission section,” “hypothetical radar transmission section,” or “hypothetical section stack” means a set of thickness and dielectric constant values ​​calculated for a combination of a hypothetical object substrate and a hypothetical coating stack. While the values ​​for each layer in a hypothetical coating stack or hypothetical section stack can be specified manually (as described for some “given” cases), this disclosure proposes automatically generating such values ​​in an iterative operation to generate as many hypothetical stacks as possible in order to find at least one hypothetical section stack that yields a radar transmission curve that best corresponds to actual or real-world data (of a “given section stack”).

[0018] Furthermore, the term “radar correction layer” is generally used herein interchangeably with “backer layer” and refers to a layer (generally a polymer film of a specific dielectric constant and thickness) applied long-term (or permanently) to the rear of the radar-transmitting section of an object, i.e., between the signal (e.g., radar) transceiver and the vehicle panel. Alternatively, a “calibration layer” or “surface calibration layer” is generally a similarly constructed material applied to the front of the transmittance section of a vehicle, i.e., to its outside. Calibration layers are typically applied only temporarily to measure a particular type of signal transmission loss, for the purpose of characterizing the substrate material layer and coating stack layer with different thicknesses of the calibration layer. However, it will be understood that both calibration layers and radar correction layers may be applied permanently or temporarily as needed.

[0019] Figure 1A illustrates one exemplary scenario in which an end-user, such as an engineer / manager / mechanic 130 (hereinafter, "mechanic"), receives an object (or, in this case, a vehicle) that requires a new coating. In this example, the object is a damaged vehicle 110 having one or more damaged sections 115. However, it will be understood that damage to a vehicle is just one of many reasons why an object may need to be coated or recoated. For example, a vehicle may require a coating of a different color on the vehicle or a part of the vehicle, or the vehicle or a part of the vehicle may require additional features of an additional coating. In either case, at some point, the end-user needs to identify the specific coating to be applied. In general, unless the user wishes to coat the object with a new color or other form of new coating, this involves the user using some analysis (e.g., spectrophotometrics or other color comparison) to identify the original coating color, coating type, and other potentially relevant information (e.g., texture effect, desired clear coat appearance). For example, Figure 1B shows that an end user uses a scanner 120, such as a spectrophotometer, to determine previously applied coating data from an object.

[0020] In the event of damage (e.g., bumper, fender, door, sensor, hood, etc.) or other forms of coating degradation, the user may first need to replace the damaged area (e.g., the damaged bumper of vehicle 140 in Figure 1A), and then coat the repaired vehicle 140 and / or the replaced area (e.g., Figure 2A) with an applicable coating determined from the original scan data. Once the desired coating has been applied, the user needs to determine the impact on the radar transmission loss (or "RTL") of any signal-generating elements within the vehicle (e.g., radar-transparent sections).

[0021] Figures 2A and 2B illustrate exemplary environments for measuring radar transmission loss values ​​after repairing a damaged section or after replacing and coating a part of the vehicle 140. Specifically, Figures 2A and 2B show the use of "Configuration A," i.e., the signal transmitter 220 (i.e., radar transmitter or radar emitter) is positioned behind the bumper, and the user installs the receiver 230 outside the bumper. However, it should be understood that this environment is merely illustrative, and the positions of the radar transmitter 220 and receiver 230 can be any position that can be considered inside or outside the vehicle 140. In addition, elements 220 and 230 may alternatively be referred to as emitter and detector, respectively. In further or alternative configurations, elements 220 and 230 may comprise a transceiver and a reflector, respectively, where the transceiver transmits and receives radar signals, and the reflector reflects the signals back to the transceiver. As understood throughout this specification in the claims, any particular device used to transmit or receive / reflect a signal may comprise any number of devices, or different combinations or substitutes thereof, insofar as signal loss can be determined through a given transparent section of an object (e.g., 140).

[0022] Referring further to Figures 2A and 2B, it will be understood that this environment is merely illustrative and the locations of the radar transmitter 220 and receiver 230 could be any location that is considered inside or outside the vehicle 140. In addition, elements 220 and 230 may alternatively be referred to as emitter and detector, respectively. In further or alternative forms, elements 220 and 230 may comprise a transceiver and a reflector, respectively, where the transceiver transmits and receives radar signals and the reflector reflects signals back to the transceiver. As will be understood throughout this specification in the claims, the particular devices used to transmit or receive / reflect can comprise any number of devices, or different combinations or substitutes thereof, as long as signal loss can be determined through a given transparent section of an object (e.g., 140).

[0023] In line with these considerations, Figure 2B further shows an enlarged schematic diagram of setting "A" with added details of the radar-transparent section of vehicle 140 in Figure 2B. Specifically, Figure 2B shows that the radar-transparent section of the exemplary vehicle 140 may include several layers of cross-sectional state, typically the substrate 240, and a coated stack of one or more layers (in this case, the exemplary coating layers 250, 260, 270). The material of the substrate 240 may include any number of materials having different signal dielectric constants, such as plastic, rubber, or a composite thereof. (Parts containing metal may be considered, although they typically have the greatest signal loss). Furthermore, the thickness and / or dielectric constant of the substrate 240 may vary from vehicle to vehicle. Moreover, after repair, the thickness and dielectric constant of the substrate 240 may differ from the original thickness and dielectric constant. Therefore, the changes in the thickness and dielectric constant of each layer after repair necessitate determining an appropriate radar correction layer that can minimize the associated signal loss.

[0024] In addition to the thickness and dielectric constant data of the vehicle / object substrate, the coating stack may include an adhesion promoter and sealer or primer layer (collectively, the “primer layer”) 250, a base coat 260, and a clear coat 270. Other coating layers may also be possible but are not shown for simplification. More generally, the coating stack may include portions of the primer layer 250, base coat 260, and clear coat 270, or it may include additional coating layers. Each of the primer layer 250, base coat 260, and clear coat 270 may have the same or different thicknesses. In addition, the dielectric constant of each layer in the coating stack may differ with thickness.

[0025] Since applied coating layers can contain different components with a wide range of different dielectric constants, and the final applied coating may be formulated as a unique mixture to provide a given color or effect, the actual dielectric constant of each layer may not be known before application. Even if the dielectric constant of each layer is known, the thickness of each layer may not be uniform or may differ from the planned thickness when applying each layer of the coating stack. Therefore, even if the type and thickness of the coating layers for all layers in the coating stack are planned or predetermined, the actual application of each layer in the applied coating stack can have a significant accompanying effect on transmission loss. Such variations during actual application also present difficulties in selecting an appropriate or suitable radar correction layer (or "backer layer").

[0026] Accordingly, as can be better understood from this specification and the claims, this disclosure may include using a combination of measurement and simulation to identify the closest matching hypothetical section stack having a specific set of values ​​that result in a predicted radar transmission loss that closely matches a previously measured radar transmission loss value of the repair vehicle 140. Similarly, further simulations may be performed to find one or more desired, optimal, predicted radar correction layers that, when applied to a combination of hypothetical substrate and hypothetical coating stacks, can minimize the radar transmission loss value or bring it below a threshold (e.g., less than 5 dB, 3 dB, 2 dB, or 1 dB) of the radar compliance requirements. Based on these simulations, one or more desired or optimal correction layers may be predicted or suggested to the end user. These details are described below.

[0027] As illustrated in Figure 2B, the measurement of radar transmission loss can be performed in a unidirectional or bidirectional manner. In the case of a unidirectional measurement, the radar receiver 230 can be positioned at a predetermined distance from the radar transmitter 220. References 280a and 280b refer to computer storage devices / storage media for storing the measurements, or computing devices for performing analysis on the measurements, as well as any related components or modules used to process and store them. In the case of a bidirectional measurement, the receiver 230 may be equipped with sensors or reflectors that can reflect signals transmitted by the radar transmitter 220 along direction 222, and the reflected signals return to the radar transmitter 220 along direction 224. Reference no. 280b may be a storage device for storing the measurements, or a computing device for performing analysis on the measurements. For brevity, only unidirectional measurements are described below. However, this can be applied to bidirectional measurements for those skilled in the art.

[0028] The illustrated radar transmitter 220 may transmit radar signals having frequencies in the range of 1 GHz to 300 GHz, such as 60 GHz to 90 GHz, 76 GHz to 81 GHz, or even 76.5 GHz or 79 GHz. The radar transmission loss can be measured on a dB scale. In other words, the power P0 received by the radar receiver 230 when the radar transmits only through air (no vehicle components between the transmitter and receiver) is compared to the received power P1 received by the radar receiver 230 when components are inserted between the transmitter and receiver. Often, radar transmission values ​​are expressed as negative dB values ​​to indicate that a loss has occurred during transmission. However, in this disclosure, positive dB values ​​are used to directly express the radar transmission loss as a loss amount given by the following formula: Radar transmission loss value (in dB) =

number

[0029] Figure 3 illustrates a plot of measured radar transmission loss data (i.e., alternative components of vehicle 140) at different frequency points for a given section stack (e.g., a bumper with applied coating layers). Specifically, Figure 3 shows that the vertical axis is a unidirectional radar transmission loss value on a dB scale, or the absolute value of the radar transmission value. Thus, the illustrated radar transmission loss curve 320 is generated by taking measured data 310 plotted approximately sinusoidally over several frequencies and then smoothed via one or more regression methods (e.g., curve fitting).

[0030] The measured radar loss data taken by the radar receiver 230 may be measured at intervals of 1 GHz, 0.5 GHz, 0.2 GHz, 0.1 GHz, or any other frequency interval suitable for finding the desired or optimal correction layer, along a specific frequency range such as 1 to 300 GHz, including 60 to 100 GHz. Figure 3 shows an example of measurements from 65 GHz to 89 GHz, where the frequency interval is 3 GHz. In other words, Figure 3 shows a plot of the exemplary measurements taken at 65, 68, 71, 74, 77, 80, 83, 86, and 89 GHz. In additional or alternative examples, the frequency interval of measurements may be less than 3 GHz or 0.1 GHz, and only representative measurement data 310 at the 3 GHz interval may be present.

[0031] Figure 3 further illustrates that the radar transmission loss at 77 GHz is approximately 3.9 dB, meaning the received power P1 is approximately 41% of the original power P0, and the radar transmission loss at 83 GHz is approximately 2.5 dB. Compared to other plotted points and consistent with the shape of curve 320, the measurement at 83 GHz appears to be the minimum transmission loss, with the received power P1 being approximately 56% of the original power P0. For the purposes of this explanation, the minimum acceptable radar transmission loss can be arbitrarily set to a given threshold such as 1.5, although the operator may use a higher or lower threshold as described above. With respect to Figure 3, the radar transmission loss value is greater than the threshold set at 1.5 dB (when the received power P1 is approximately 71% of the original power P0), and the plotted minimum value is above 2.4, so it can be understood that the radar system for vehicle 140 is unlikely to operate at full capability due to excessively high radar transmission loss while operating at any given frequency. Therefore, a radar correction layer (or "backer layer") may be required to reduce or potentially minimize the radar transmission loss value, bringing the vehicle 220's radar transmission loss (RTL) to less than 1.5 dB.

[0032] Therefore, since the exact thickness and dielectric constant values ​​of the repair component of vehicle 140 (Figure 2A) may not be known, aspects of the present disclosure enable the creation of several different assumed section stacks that can be used to generate similar radar transmission loss (RTL) points over different frequencies, thereby creating a simulated radar transmission loss curve, or a simulated RTL curve for each particular assumed section stack. The simulated RTL curves for each assumed section stack can then be compared to best fit the shape of the curve shown for the repair portion of vehicle 140 (Figure 2A), such as the measurement curve shown in Figure 3.

[0033] As further explanation, and also as stated above, the actual combination of substrate layers and actual coating layers is not usually necessary, especially considering that the analysis may not generally be known, given that the thickness and dielectric constant values ​​of each layer may be unknown when applying it to a new coating. Instead, this disclosure provides a combination of simulated hypothetical substrate layers and hypothetical coating stacks (collectively, "hypothetical section stacks"). This disclosure can further use these hypothetical section stacks to predict the corresponding radar transmission loss values ​​and curves for each hypothetical section stack and compare them to a given, such as an actual curve measured for the repair vehicle 140. To do so, this disclosure proposes matching data points that are sufficiently close within an appropriate threshold, such as less than 0.1 dB RSME, such as less than 0.03 dB, to the measurement data 310 of the repair vehicle 140. The predicted radar transmission loss of the hypothetical stacks for comparison with the actual values ​​(Figure 3) is shown in The Transfer-Matrix Method in Electromagnetics, TGMackay and A. Lakhtakia, Principles of Optics, 7 th As described in various references such as (expanded) edition, M. Born and E. Wolf, Section 1.6, Handbook of Optics, Chapter 42, “Optical Properties of Films and Coatings”, JAD Browolski, and SJByrnes, “Multilayer Optical Calculations”, the electromagnetic plane wave reflection and transmission characteristics of a layered medium can be calculated from the dielectric constant and thickness of each layer using the transfer matrix method (TMM), and the entire contents of these references are incorporated herein by reference.

[0034] In line with these objectives, Figure 4 shows a block diagram of the simulation system 400, which performs simulations with various generated assumption stacks 410a to 410n, which are generated to find agreement with the radar penetration loss measured for the repair vehicle 140. The assumption section stacks can be created with computer-generated values ​​in the expected rage for each expected layer in a typical coating stack, and then the computer system can model the radar penetration loss curve for each given assumption section stack. Specifically, the computer system can be configured to compare the simulated radar penetration loss curve for any given assumption stack against the measured radar penetration loss curve for the radar penetration section of the vehicle 140 (e.g., 320 in Figure 3).

[0035] Figure 4 further illustrates that the simulation system 400 may include a “simulator” 420, a “comparator” 440, and a “tuner” 450. These various terms will be understood to refer to various computer components, modules, or processing elements that execute instructions to provide specific results. For example, in response to various inputs, which will be more fully understood herein, the simulation system 400, together with the tuner 450, comparator 440, and simulator 420, may use the various inputs to output a stack 460 of one or more desired assumptions about the radar-penetrating section.

[0036] As already stated, the exemplified hypothetical stacks 410a-410n have values ​​and layers generated as accurately as possible to represent the same (or substantially similar) stack arrangements used in actual measurements of vehicle substrates having applied coating layers, such as the stack shown in Figure 2B. Wherever possible, the variables of the hypothetical section stack layers match the actual (but unknown) variables of the coating actually applied on a given object 140. However, in terms of the views of this disclosure, it will be understood that when comparing a generated hypothetical section stack or hypothetical section stack with an actual coating stack or actual section stack, there does not need to be a 1:1 correlation between layers, layer thickness, or corresponding dielectric constant values. Again, in this case, at least in some cases, it is sufficient to measure the shape of the curve resulting from the radar transmission loss value, which arises from a simulation of the shape of the measured curve value. Further in line with these intentions, the variables of the hypothetical section stack layers do not need to match the actual (but unknown) variables of the coating actually applied on a given object 140 in terms of thickness and dielectric constant. Each layer of assumptions in the assumption stack can contain dielectric constant values, including both real and imaginary dielectric constant values.

[0037] For illustrative purposes, Table 1 includes examples of thickness values, real dielectric constant values, and imaginary dielectric constant values ​​selected or chosen for various layers of several different “given section stacks,” as shown below, representing an actual or real-world representation or simulation of a section stack (i.e., a part of an object or vehicle coated with one or more coating layers). The ten “given section stacks” illustrated in Table 1 were prepared for testing purposes to provide various criteria for comparison as real-world object section stacks on which multiple hypothetical section stacks are compared. Thus, each of the following given section stacks 1-10 in Table 1 can be considered to represent, alternatively, ten different real objects or vehicles, and the corresponding measurements of a given section stack for each vehicle, i.e., measurements of a specific thickness and dielectric constant value in any particular layer within the section stack of each specific vehicle (e.g., 1-10) in its radar-penetrating section. [Table 1]

[0038] Referring again to Figure 4, for a “given section stack” in Table 1 (or for any vehicle accepted for repair), one or more hypothetical section stacks (i.e., a set of stacks 410a) can be created, each expected layer having a variety of “trial variables” of generated actual and / or imaginary dielectric constant and thickness values, in order to create predicted radar transmission loss for comparison against a specific given (e.g., one of the givens 1-10 in Table 1). A computer system can be used to iteratively generate various hypothetical section stacks with a variety of computer-generated trial variable values ​​for the layers, such as thickness and dielectric constant values ​​within acceptable ranges. The generated dielectric constant and thickness values ​​can then be used by simulator 420 to prepare a set of predicted radar transmission loss values ​​(i.e., simulated radar transmission loss values, or “predicted RTL”) for each hypothetical section stack at any specific frequency value in the range of 1-300 GHz, such as the 60 GHz-90 GHz range as shown in Figure 3. Generally, simulator 420 sets up a simulation environment that attempts to adopt an environment as close as possible to the actual environment in which measurements are taken. For example, simulator 420 may include the frequency resolution setting of the radar receiver 230, or other mechanical issues that may need to be considered. Using these settings, simulator 420 can perform simulations with assumed stacks 410a to 410n, thereby generating predicted radar transmission loss values ​​430a to 430n derived from combinations of layer values ​​for each of the generated assumed stacks 410a to 410n.

[0039] In one example, simulator 420 may perform simulations serially, meaning that a simulation of one assumption stack is performed first, followed by a simulation of another assumption stack. Similarly, each simulation result of the predicted values ​​for each assumption section stack (i.e., predicted radar transmission loss values ​​430a-430n) may be compared serially with the measured radar transmission loss values ​​(e.g., measured data 310 in Figure 3) by comparator 440. Adjustment of the “trial variables” (i.e., the thickness and dielectric constant of each layer of a particular assumption section stack) by tuner 450 may be performed immediately after all simulations and comparisons have been performed, and no assumption stack matching the measured data 310 is found within the threshold. In another example, simulator 420 may perform simulations in parallel, meaning that simulations of assumption stacks (410a-n) are performed in parallel by the corresponding parallel computing modules within simulator 420. Next, parallel computing can yield simulated radar transmission loss values ​​430a to 430n, which are essentially generated in parallel and can be plotted sequentially to form a curve of a specific shape, similar to the plot of the given data in Figure 3.

[0040] When compared against the vehicle 140, the comparator 440 may further compare each of the simulated radar transmission loss values ​​430a to 430n for each assumed section stack with measured data (e.g., from an actual object), such as the data point 310 in Figure 3. The differences at each frequency may be calculated and combined to produce the total difference between each simulated radar transmission loss value and the measured data 310. The difference may be the sum of arithmetic differences, RMSE, ratio, or any other mathematical measure.

[0041] For example, comparator 440 can calculate mathematical measures. For instance, the L-1 error is the sum of the absolute values ​​of the distances for each frequency, as calculated by equation (1) below, and the L-2 error may be the root mean square error (or RMSE), as calculated by equation (2) below.

number

number

[0042] In cases where the dB RMSE difference is less than a threshold (e.g., less than or equal to 1 dB, less than or equal to 0.3 dB, 0.1 dB, 0.03 dB, 0.01 dB, 0.001 dB, or any other suitable value in dB units), the corresponding assumed stack can be determined to correspond to the vehicle's radar-penetrating sections. This may become apparent when plotting the predicted radar-penetrating loss points at any given frequency for a particular assumed section stack and showing how the resulting curve overlaps with the curve of the plotted points from a given section stack (e.g., Figure 5).

[0043] In other cases where the difference does not fall below a threshold, the tuner 450 may adjust trial variables, such as the thickness of each layer, the real dielectric constant, or the imaginary dielectric constant, for further simulation by the simulator 420. These simulations, comparisons, and adjustments of the trial variables for each layer in the hypothetical stacks 410a to 410n may be repeated until it is determined that one or more hypothetical stacks have simulated radar transmission loss data and curves that match the actual measurements of a given section stack.

[0044] Once a hypothetical section stack (or stack) with a predicted radar transmission loss value that matches a measured value (e.g., Figure 3 for vehicle 140) or one of a given section stacks 1-10 is identified, the simulator can model various radar correction layers that adjust the radar transmission loss value of the matching hypothetical section stack(s) until a radar correction layer of a specific thickness and / or dielectric constant is identified that reduces the radar transmission loss value of the matching hypothetical section stack(s) to an acceptable minimum.

[0045] Table 2 (below) shows examples of tuning by the tuner 450 both before and after the radar correction layer (or backer layer, BL) is applied to a particular assumed stack 410a. Specifically, Table 2 shows that adding a radar correction layer of specific dimensions and dielectric constant to a particular assumed section stack can significantly reduce the predicted radar loss of that assumed section stack, i.e., minimize the predicted radar transmission loss value of the particular assumed stack so that the predicted transmission loss of that particular assumed section stack within a desired frequency range falls within a certain threshold. [Table 2]

[0046] Based on Table 2, System 400 determined that, in the case of the first assumed section stack and considering a frequency of 76.5 GHz, a radar correction layer with a thickness of 493 μm and a real dielectric constant of 4 could reduce the predicted radar transmission loss of that assumed section stack from 2.82 dB to 0.71 dB. Rounded to the nearest 100 μm, this considers the proposed radar correction layer to be 500 μm. However, it will be understood that rounding to the nearest 100 μm is not necessary, and the size of the radar correction (or backer layer) can be adjusted to 50 μm or 25 μm increments.

[0047] Of these stacks of assumptions, the fifth assumption without a radar correction layer has a radar transmission loss of 4.02 dB at 76.5 GHz, similar to the measured loss of approximately 3.9 dB at 77 GHz, as shown by curve 320 in Figure 3. However, in the case of coating a radar correction layer with a real dielectric constant of 4 and an optimized thickness of 220 μm, the radar transmission loss at 76.5 GHz is approximately 1.84 dB or 1.87 dB, with the radar correction layer thickness rounded to the nearest 100 μm. However, both 1.84 dB and 1.87 dB are still below the threshold, which can be 3.0 dB, 2.0 dB, 1.5 dB, 1.0 dB, 0.5 dB, or less, as mentioned. That is, 1.84 dB and 1.87 dB are above the 1.5 dB threshold and below the 3.0 dB threshold. Therefore, in order to ensure that this assumed section stack has a lower transmission loss rate, radar correction layers with different dielectric constants and / or thicknesses can be evaluated in simulator 420 and comparator 440.

[0048] Therefore, in order to bring the radar transmission loss values ​​of each assumed section stack closer to the measured radar transmission loss data of a given section stack (e.g., from Table 1), the tuner 450 may adjust the trial variables of the layers within each assumed stack until they closely match the predicted radar transmission loss data for any given section stack. For example, the tuner 450 adjusts the real and imaginary dielectric constants and thicknesses of the substrate, primer layer, base coat, and clear coat for a particular assumed section stack. In one example, if certain trial variables of an assumed stack have little effect on the change in the difference from the measured data for a given, the tuner 450 may provide a setting to keep them constant in order to reduce the computational power required for the simulation. In this regard, the tuner 450 may allow several assumed trial variables to be kept constant.

[0049] For example, Table 3 shows the parameters (or "trial variables") of a section stack for a particular assumption that are modified by the tuner 450, along with other parameters that are kept constant. [Table 3]

[0050] In an additional or alternative example, the tuner 450 may utilize a generalized reduced gradient nonlinear method when tuning parameter values. Specifically, the generalized reduced gradient nonlinear method can determine whether to increase or decrease each parameter value to approximate the measured data. By increasing or decreasing each parameter value in small increments, the tuner 450 may be able to find the optimal combination of trial variables for each assumption stack.

[0051] For example, as shown in Table 4 below, the tuner 450 sets the real and imaginary dielectric constants among the trial variables for the base coat and clear coat to constant and adjusts the trial variables for other hypothetical section stacks. After iteratively adjusting the trial variables for the hypothetical section stacks based on the generalized reduced gradient nonlinear method, the tuner 450 can find the optimal trial variables that yield predictive radar transmission loss closely corresponding to a particular "given section stack" in Table 1. For example, this result can be determined for any particular hypothetical section stack, where various layer values ​​are adjusted until the predictive transmission loss value for any particular hypothetical section stack matches the measured data 310 with the actual or given section stack within a suitable small RMSE variation, such as less than 0.1, including less than 0.03 dB, as shown in Table 6.

[0052] Table 4 shows the desired and / or optimal values ​​for layers in the assumed section stack based on the generalized reduced gradient nonlinear method. These desired assumed stacks 460 with the following parameter values ​​are output by comparator 440, as shown below. [Table 4]

[0053] Another tuning method can be applied to the assumed stacks 410a to 410n. For example, the memory-limited Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) or range-constrained memory-limited Broyden-Fletcher-Goldfarb-Shanno (L-BFGS-B) method can be used by tuning device 450. In each iteration, the increasing or decreasing direction can be determined for each trial variable, with corresponding boundaries for each trial variable, according to the L-BFGS and L-BFGS-B methods. The L-BFGS-B method can further use line search techniques to determine a variable step size along the increasing or decreasing direction. In this case, the trial variables of the real and imaginary dielectric constants and thickness of the base coat and clear coat are set constant, and the other trial variables are tuned based on the L-BFGS-B method. Based on the L-BFGS-B method, the trial variables of the layers of each assumed stack are optimized as shown in Table 5 below. [Table 5]

[0054] The results of these two methods (the generalized reduced gradient nonlinear method and the L-BFGS-B method) are illustrated in Figure 5.

[0055] Specifically, Figure 5 shows various data plots of both actual and simulated data overlapping each other. For example, data 510 contains predicted radar transmission loss values ​​for a section stack under specific assumptions, generated through simulator 420. In the example, data plot 310 represents actual measured data for the transmission sections of an object (e.g., vehicle 140 having sections 240, 250, 260, and 270). Curve 320 is a visual representation of data plot 310 as a smooth solid curve. Similarly, data plots 510 and 530 are simulated radar transmission loss values ​​based on two methods (e.g., the generalized reduced gradient nonlinear method and the L-BFGS-B method), and curves 520 and 540 are short dashed and long dashed curves, respectively, that fit data plot 310 with the loss values ​​measured based on the two methods. This fit is so close to that of the solid curve 320 that curve 520 (the short dashed curve) is not visible in Figure 5. These two methods for regulator 450 are provided as examples, and other adjustment methods may also be used for regulator 450.

[0056] Therefore, the hypothetical section stack that generated the predicted radar transmission loss values ​​510 and 530 is determined to be a sufficiently close analogue to the given section stack modeled and formulated in Figure 3. Thus, it will be understood that a radar correction layer that modifies the hypothetical section stack that generated the values ​​510, 530, etc., can be applied to that given section stack corresponding to Figure 3. Thus, the user can further use the simulator system described herein to find a suitable radar correction layer that can improve the expected radar transmission loss for a matching hypothetical section stack, and thus for a given section stack. This can be done, for example, by using the simulation system 600 illustrated in Figure 6. For illustrative purposes, each of the simulation components, tuner components, and comparator components described herein may be the same or different sets of components deployed in one or more computing systems. Therefore, the distinct numbering used herein for each component is, in particular in certain contexts, for convenience in illustrating a given simulator, tuner, or comparator.

[0057] Figure 6 shows an example of a computing system simulating the use of desired assumed radar correction layers 610a–610m added to the stack 460 of each identified assumption, along with the resulting radar transmission loss. In general, each of the proposed radar correction layers 610a–610m may have different thicknesses (and / or dielectric constants) from each other, and thus provide different simulated transmission loss values ​​630a. Furthermore, each radar correction layer may be a combination of two or more radar correction layers having the same or different thicknesses and / or dielectric constants for different transmission loss effects.

[0058] Figure 6 further shows the results from the simulator 620, i.e., the simulated radar transmission loss values ​​630a 630m. Next, the comparator 640 may compare the simulated radar transmission loss values ​​630a 630m to thresholds based on the radar compliance requirements. The comparator 640 may then determine which radar correction layer is optimal, or it may output one or more desired radar correction layers 660 if the radar correction layer brings the predicted radar transmission loss below an acceptable threshold (e.g., 5.0dB or less, such as 3.0dB, 2.0dB, 1.5dB, 1.0dB, 0.5dB, or less). In other words, if there is a given radar correction layer that, when simulated with a matching assumed section stack, produces an acceptable radar transmission loss within the appropriate frequency range of that assumed section stack, then the radar correction layer (or set of layers) can be recommended to the user for use with the relevant given section stack, where the assumed section stack is considered a good match.

[0059] This simulation can be performed for any given section stack (Table 1) until an acceptable assumed section stack and appropriate radar correction layer(s) are determined to make the given section stack conform to radar penetration loss requirements. If two or more potential radar correction layers provide simulated radar penetration loss values ​​below a threshold, the comparator 640 may output a desired radar correction layer 660 that provides the lowest (or best) simulated radar penetration loss value, such that only one optimal radar correction layer is output for each desired assumed stack 460. Alternatively, the comparator 640 may output a list of multiple radar correction layers, which conform to the desired assumed stack 460 and radar correction layer radar combination. The end user may select one or more of the displayed radar correction layers and then apply the selected radar correction layer(s) to the appropriate location on the object (e.g., the rear of the radar-penetrating section of a vehicle).

[0060] Table 6 shows the application of the radar correction layer to the section stack under specific assumptions from Table 4, where the radar correction layer is obtained based on a generalized reduced gradient nonlinear method. Table 6 also shows the given dielectric constant (ε' BL ) is the thickness (d) of each radar correction layer or backer layer (i.e., "BL") output by comparator 640 for each assumed section stack from Table 4. BL ) is also illustrated. Table 6 further shows a comparison of the RTL values ​​of the hypothetical section stacks as measured against the given section stacks they were compared to. Table 6 shows that in this case, all of the hypothetical section stacks had RMSE values ​​of less than 0.03 dB compared to the given section stacks they were compared to. [Table 6]

[0061] Table 6 further shows that system 600 determined an appropriate radar correction (or backer) layer thickness value using one assumed dielectric constant value (e.g., 2.5, 3, or 4). Nevertheless, those skilled in the art will understand that simulation system 600 can provide a set of possible dielectric constant values ​​for a radar correction layer for a given assumed stack, and the thickness can be optimized for each, allowing for the selection of a radar correction layer with the lowest radar transmission loss. Alternatively, simulation system 600 can determine both the optimal dielectric constant and thickness for a radar correction layer, which is computationally and theoretically feasible, but may also be impractical as end users may not have adequate means to adjust the dielectric constant of the radar correction material composition. Therefore, more generally, simulators 420, 620 can keep the dielectric constant constant constant (e.g., a recommended or known value for each proposed layer material in the stack) and allow for the adjustment of the thickness.

[0062] If the RMSE of the radar transmission loss curve of the hypothetical stack in Table 6 is 0.03 dB or less compared to that of the given section stack in Table 1, then all of the hypothetical stacks provide a satisfactory good agreement with the radar transmission loss curve of the original given section stack shown in Table 1. Table 6 also shows that all of the hypothetical stacks (except #8) provide a very good agreement with an RMSE value of less than 0.01 dB. Furthermore, seven of these ten hypothetical stacks (all except #2, #8, and #10) provide a very good agreement with an RMSE value of less than 0.005 dB. The smaller RMSE values ​​in Table 6 compared to those in Table 2, the very close values ​​resulting from the predicted radar correction layer thickness in Table 6, and finally, the exact values ​​of the radar correction layer in Table 6 rounded to the nearest 100 μm compared to those in Table 2, demonstrate that a suitable radar correction layer for a given section stack can be predicted by creating a hypothetical stack that provides predicted radar transmission loss at various frequencies, in order to match those measured for the original given section stack.

[0063] In line with the above, the difference in radar transmission loss values ​​between a given section stack and a matched assumed section stack is shown in Table 7 below. The values ​​in Table 7 are generated by employing L-BFGS-B in the desired assumed stack in Table 5 (simulated, for example, by simulation system 600), and the resulting RMSE, as well as the corresponding thickness and dielectric constant values ​​of the radar correction layer (or backer layer - "BL"), and the results are shown in Table 7 below. [Table 7]

[0064] Figure 7 illustrates a curve 710 obtained as a result of radar transmission loss over frequency based on an optimized radar correction layer, or a desired assumption section stack combined with a backer layer ("BL"). In particular, after application of the desired radar correction layer found based on the simulation system 600, the unidirectional radar loss curve 710 falls below the threshold T1 over a range of frequencies. Using this curve (or a similar one for each simulation of the backer layer / assumption section stack), an end user can select a desired radar correction layer that provides a value less than "T1" within a preferred frequency range. The user can then take an actual radar correction layer that matches the dielectric constant and thickness of the optimal radar correction layer identified by the computer (i.e., the selected radar correction layer), and then apply the selected radar correction layer to the rear of the radar-transmitting section of the vehicle / object. The end user can then specify the radar transmission loss value of that particular radar-transmitting section to ensure that it meets the radar compliance requirements. As stated herein, radar compliance requirements can be any value, but in specific cases they will represent a transmission loss of 5 dB or less, such as 3 dB, 2 dB, or 1 dB.

[0065] As described above, it is not always necessary that the number of layers in a given section stack match the number of layers and values ​​calculated for a given assumed section stack. The number of layers can, to varying degrees, be in a given section stack and, to varying degrees, be in an assumed section stack. The analysis disclosed herein still works as long as the predicted or simulated radar transmission loss values ​​match between the assumed section stack and the given section stack being compared.

[0066] Considering this, Table 8 below demonstrates that even if a given section stack consists of multiple layers, the hypothetical stack can be generated with fewer layers than the actual number, and a good match with the radar loss of the given section stack can still be achieved. [Table 8]

[0067] The first six rows of Table 8 represent a smaller set of variables (fewer coating layers) for a given section stack in Table 1 (compared, for example, to Tables 4 and 5). In Table 8, a generalized reduced gradient nonlinear method (simulator 420) is used to generate dielectric constant and thickness values ​​for the hypothetical stacks, and the resulting radar transmission loss curves for these hypothetical stacks still match those of the given section stack in Table 1 with an RMSE of less than 0.03 dB. Using these hypothetical section stacks, simulator 620 provides radar correction layer thicknesses shown in Table 8 (see Table 2) that closely match those previously generated for the given section stack in Table 1. Similarly, the radar correction layers for the hypothetical stacks in Table 8 (except for #10) exactly match those in Table 2. Thus, according to this disclosure, it is not necessarily required to model a given section stack with hypothetical stacks having the same number of coating layers in order to match the radar loss curve of a given section stack with an RMSE better than 0.03 dB. Therefore, as long as a hypothetical section stack generated in substantially any composition can produce a radar transmission loss value that is sufficiently close to the radar transmission loss value measured for a given section stack, the determined radar correction layer, which corrects a hypothetical section stack that does not match well, still corrects the radar transmission loss of a given section stack that matches well, in the same manner.

[0068] In addition to the above, which intends to take measurements taken over a number of frequencies, this disclosure can also be applied to situations where only one or a selected number of frequencies can be measured. For example, some radar measurement devices may be capable of radiating and detecting radar loss in a fairly narrow bandwidth, such as just 76.5 GHz, or in the 76 GHz to 81 GHz range. In such a configuration, where a pair of radar transmitters / receivers (e.g., radar transmitter 220 and receiver 230 in Figure 2B) can instead radiate only one, two, or three frequencies, additional, or further described below, measures may be employed. Using such measures, multiple datasets can still be collected by measuring transmission loss in contrast to a transmission section stack and a set of one or more different radar calibration layers arranged by thickness.

[0069] Therefore, in contrast to Figures 1–7 and their corresponding explanations, which identify the hypothetical section stack and backer layer based on data taken over multiple frequencies, Figures 8–10 can be used to essentially characterize the hypothetical section stack and radar correction layer as a function of measurements taken over different thicknesses of the surface calibration layer over a single or limited frequency. That is, the plots can be generated by changing the thickness of the calibration layer, rather than the frequency. The ultimate goal of Figures 8–10 is essentially the same as identifying the hypothetical section stack, from which the transmission loss curve of a given section stack can be approximated.

[0070] For example, Figure 8 shows a block diagram of a simulation system 800 that measures radar transmission loss values ​​with one or more surface calibration layers 880a to 880p at one (or limited) frequency. Reference numbers 820, 822, 824, 830, 840, 850, 860, 870, 890a and 890b may correspond to reference numbers 220, 222, 224, 230, 240, 250, 260, 270, 290a and 290b in Figure 2B. Thus, the descriptions of reference numbers 820, 822, 824, 830, 840, 850, 860, 870, 890a and 890b can be found in the corresponding descriptions in Figure 2B above, and the different characteristics of such numbers are described below. The surface calibration layers 880a to 880p will be understood as any arrangement of one (or more) calibration layers 880a(a...p).

[0071] In this configuration, the transmitter 820 may emit radar, and the receiver 830 may measure radar transmission loss values ​​at one, two, or three frequencies (e.g., 76.5 GHz or 79 GHz). In one example, the transmitter 820 and receiver 830 may measure radar transmission loss values ​​at one, two, or three frequencies, but not across a range of frequencies (e.g., 60 GHz to 90 GHz with a resolution of 0.1 or 1 GHz).

[0072] To obtain measurement data with this configuration, the user may apply one or more surface calibration layers 880a to 880p to the front of the radar-transmitting section of a vehicle, including a given object substrate 840 and a hypothetical section stack. As already mentioned, the illustrated hypothetical section stack includes representations of a primary layer 850 (including adhesion promoter and sealer), a base coat 860, and a clear coat 870. The dielectric constant of each calibration layer is generally kept constant, but the thickness of each arrangement varies. The arrangement may then include calibration layers of the same thickness stacked together to achieve the added thickness, or, in the first case, simply a thicker calibration layer. The user can then provide various arrangements of one or more calibration layers 880a to 880p to the front (or rear) of the transparent section of a given object. In the example, "p" may be the maximum number of calibration layers and may vary depending on the estimated number of trial variables for the layers. For example, if some trial variables in the layers of the assumption stack are set to constant, then "p" may be smaller than when all trial variables in the layers of the assumption stack are not constant.

[0073] In this configuration of Figure 8, the measured radar transmission loss values ​​are illustrated in the data plot 910 of Figure 9, which plots the radar transmission loss against variations in the thickness of the surface calibration layer, in this case representing various arrangements of the calibration layer (and thus varying thicknesses). When the thickness is zero (or no calibration layer is applied), the corresponding data points shown reflect the radar transmission loss values ​​of the layer in the radar transmission section without a calibration layer. Along the horizontal axis, "1D" represents the thickness of one calibration layer, "2D" represents the thickness of two calibration layers (whether multiple 1D thickness calibration layers or a single thicker calibration layer), and so on. The number and / or thickness of the calibration layers may vary depending on the number of trials required to obtain sufficient data. Thus, the horizontal axis has a maximum value of "6D", but the horizontal axis may have "pD" where p is greater than 6.

[0074] The data plot 910 can be obtained by measuring radar transmission loss values ​​in series by applying one additional calibration layer at a time up to a maximum of "p" calibration layers. Alternatively, the data plot 910 can be obtained by first applying one or more "p" calibration layer arrangements and then removing the arrangements (or parts thereof) at a time until all calibration layers have been removed, while measuring radar transmission loss values ​​in series. Thus, the curve 920 can be fitted to the data plot 910 and obtained through one or more curve fitting methods.

[0075] Based on data plot 910 or curve 920, a stack of one or more desired assumptions may be found by the simulation system 1000 in Figure 10, which may include the same or alternative components as those already described for Figures 4 and / or 6. The simulation system 1000 may measure radar transmission loss values ​​having one or more calibration layers at at least one frequency (e.g., 76.5 GHz or 79 GHz). The simulation system 1000 may include a simulator 1020, a comparator 1040, and a tuner 1050. The simulator system 1000 may output a stack 1060 of one or more desired assumptions.

[0076] Referring further to Figure 10, the initial assumed stacks 1010a to 1010q may include layer variables, for example, various layer variables corresponding to a given section stack, in addition to the surface calibration layer variables, as shown in Table 1 above. Simulator 1020 can perform simulations for each assumed stack for the case of zero to the maximum number of calibration layer coatings at one frequency. The results of simulator 1020 are the simulated or predicted radar transmission loss values ​​1030a to 1030q over the calibration layer thickness. Comparator 1040 can compare the simulated radar transmission loss values ​​1030a to 1030q with the measured radar transmission loss value 910.

[0077] If the error or difference between the simulated radar penetration loss values ​​1030a~1030q and the measured radar penetration loss value 910 is less than another threshold, the corresponding assumption stack may be output as the desired assumption stack 1060, which may be a good candidate for the vehicle's radar penetration section.

[0078] If the error or difference between the simulated radar transmission loss values ​​1030a-1030q and the measured radar transmission loss value 910 does not fall below a threshold, the tuner 1050 may adjust the trial variables of the layers. These adjustments generally involve adjusting one or both of the dielectric constant and thickness of each layer in the assumed section stacks 1010a-1010q. This adjustment may employ the Generalized Reduced Gradient Nonlinear Method, L-BFGS, L-BFGS-B, or any other readily available method to determine whether to increase or decrease each trial variable (e.g., change each thickness and / or dielectric constant of each assumed section stack layer) until an assumed stack is identified that matches the measured values ​​of the actual transmission sections and a given arrangement of surface calibration layers. By iterating through simulation, comparison, and adjustment, the simulation system 1000 may be able to output a desired assumed stack 1060 that mimics the measured data 910.

[0079] As previously described with respect to the application of radar correction layers and the measurement of their effects in Figures 1-7, once the possible stacks of assumptions that can be applied are identified, Figure 11 shows that the simulator 1120 can find a radar correction layer that provides an acceptable radar transmission loss in combination with the desired stack of assumptions 1060. In this regard, as illustrated in Figure 11, the simulation system 1100 may include the simulator 1120 and the comparator 1140. The simulator 1120 may add one or more radar correction layers 1110a-1110r to each of the desired stacks of assumptions 1060, perform simulations for the combinations, and output simulated radar transmission loss values ​​1130a-1130r. Each simulated radar transmission loss value can then be compared by the comparator 1140 to a threshold required by the radar compliance requirements. If the radar transmission loss is below the threshold, the system can then provide the determined ideal radar correction layer as an output. It will be understood that not all radar correction layers / backer layers will help achieve a conformed minimization of radar transmission loss based on a given assumed transmission section. Whether a radar correction layer makes a given assumed transmission section usable depends largely on the intrinsic dielectric constant of the radar correction layer's material composition and / or its thickness.

[0080] Figure 12 illustrates a curve 1210 of radar transmission loss values ​​after simulation using a coated backer layer, where T2 represents the threshold for radar compliance requirements. As illustrated, after coating a desired radar correction layer found based on the simulation system 1100, the curve 1210 is positioned below the threshold T2 at a frequency (e.g., 76.5 GHz or 79 GHz). The end user can then select one of the desired radar correction layers. The end user can then coat the rear of the radar-transparent section of the vehicle with the selected radar correction layer so that the radar transmission loss value meets the radar compliance requirements.

[0081] As previously mentioned, Figures 1A–12 provide several components, modules, and schematic diagrams as part of a system to provide a workflow in an automotive repair shop to provide a list of radar correction layers(s) for creating newly coated vehicle sections to meet the radar compliance requirements of radar transceivers equipped for driver assistance systems within a vehicle. This disclosure can also be described in terms of one or more methods for achieving similar results. In line with these intentions, Figures 13 and 14 illustrate various methods for creating newly coated sections of vehicle radar complaints. The operations and steps illustrated in Figures 13 and 14 will be discussed below with reference to the components and modules illustrated in Figures 1A–12.

[0082] For example, Figure 13 illustrates a method 1300 for radar-compliant a newly coated vehicle section by applying a desired radar correction layer to a repaired vehicle radar-penetrating section (e.g., the repaired radar-penetrating section 145 in Figure 1B). Operation 1310 may include receiving measured radar-penetrating loss values ​​over a frequency range. The radar transmitter 220 and radar receiver 230 in Figure 2B may be used to measure radar-penetrating loss values ​​over a frequency range. The simulation system 400 in Figure 4 may receive measured radar-penetrating loss values.

[0083] The frequency range can span 1 GHz to 300 GHz, such as 60 GHz to 90 GHz, 76 GHz to 81 GHz, 76 GHz to 77 GHz, or 77 GHz to 81 GHz. Measurements can be performed in units of 1 GHz, 0.1 GHz, or any other suitable frequency interval.

[0084] In addition, Figure 13 shows that Method 1300 may include Operation 1320, in which a simulation system (e.g., 400 in Figure 4) generates a set of trial variables for a hypothetical stack. The trial variables may include thickness and dielectric constant values ​​for each layer of the hypothetical stack corresponding to the radar-transparent section. For example, the hypothetical radar-transparent section may include a substrate 240, a primer layer 250, a base coat 260, and a clear coat 270 in Figure 2B. Each layer has an associated set of dielectric constant and thickness values ​​over a frequency range.

[0085] Operation 1320 may further include performing a simulation for each assumed radar-penetrating section using a simulator (e.g., simulator 420 in Figure 4).

[0086] In addition, if the simulated transmission loss value for each assumed stack is not the same as the measured radar transmission loss value within the tolerance range (e.g., using RMSE), Figure 13 shows that method 1300 may include operation 1330 to adjust the trial variables for each assumed stack. The trial variables may be the thickness and dielectric constant of the substrate (substrate), adhesion promoter and sealer or primer layer (A&S), base coat (base coat), and clear coat (clear coat) of the layers in the assumed stack. In one example, a tuner (e.g., tuner 450 in Figure 4) may set some of the trial variables constant and change others.

[0087] The tuner may employ a generalized reduced gradient nonlinear method, LBFGS, L-BFGS-B, or any other preferred method to determine whether to increase or decrease the trial variable. By determining the direction of increase or decrease of the trial variable, the tuned trial variable of the assumed stack may have a radar transmission loss value close to the measured radar transmission loss value within the RMSE below the threshold.

[0088] In response to iterative adjustments, Figure 13 shows that method 1300 may include operation 1340 which performs a computational optimization routine. During the computational optimization routine, a simulator (e.g., simulator 620 in Figure 6) may coat several radar correction layers with different thicknesses and dielectric constants onto a tuned assumption stack, and based on the combination of the tuned assumption stack and the radar correction layers, it may perform a simulation to generate simulated radar transmission loss values.

[0089] If the simulated radar transmission loss value is below the radar compliance threshold (e.g., 3.0 dB or less, 2.0 dB, 1.5 dB, 1 dB, 0.5 dB, or any other appropriate threshold required in this situation), then such a radar correction layer is determined to be the predicted radar correction layer.

[0090] Furthermore, Figure 13 also shows that method 1300 may include an operation 1350 to display the predicted radar correction layer. Based on the displayed predicted radar correction layer, an engineer / manager / maintenance technician / end user (e.g., end user 130 in Figure 1A or 1B) may select one of the predicted radar correction layers and apply the selected predicted radar correction layer to the rear of the radar-transparent section such that the combination satisfies the radar compliance requirements. In at least one embodiment, the display of the predicted radar correction layer(s) may include displaying instructions for the additive manufacturing of the radar correction layer(s), including any material composition requirements.

[0091] In addition to the above, Figure 14 illustrates that a method 1400 for predicting the radar correction layer may include an operation 1410 for receiving radar transmission loss values ​​measured at a frequency over a range of calibration layer thicknesses. The frequency may be 76.5 GHz or 79 GHz, and the frequency range may be 1 GHz to 300 GHz, 60 to 90 GHz, 76 GHz to 81 GHz, 77 GHz to 81 GHz, or any other suitable range.

[0092] Operation 1410 may further include applying one or more calibration layers to a radar-transparent section (e.g., a repaired radar-transparent section 145 in Figure 1B) of a physical object (e.g., a vehicle 140 in Figure 1B). The radar-transparent section comprises a substrate and a plurality of coating layers applied to the substrate. The plurality of coating layers may include, in any number or type of arrangement, adhesion promoter and sealer or primer layers (A&S), a base coat, and a clear coat. In one example, each of the one or more calibration layers has the same dielectric constant value and the same thickness value. In other examples, one or both of the dielectric constant and thickness values ​​may be varied. Radar-transparent loss value data for the combination of the radar-transparent section and one or more calibration layers are received by the simulation system 1000 in Figure 10.

[0093] The measured radar transmission loss data may include radar transmission loss values ​​at various frequencies, with zero, one, two, ..., and "p" calibration layers applied on top of it. Thus, the measured radar transmission loss data can be plotted over the thickness of the calibration layers, as illustrated in Figure 9.

[0094] In addition, Figure 14 shows that method 1400 may also include operation 1420 to generate multiple predicted transmission loss values ​​from multiple trial variables in the form of dielectric constant values ​​and thickness values. Specifically, the simulation system 1000 in Figure 10 generates multiple assumption stacks to simulate a radar transmission section, and the simulator 1020 of the simulation system 1000 performs simulations to generate radar transmission loss values ​​based on each assumption stack and combinations of multiple calibration layers. Calibration layers may be applied to the front or rear of the assumption stacks.

[0095] Furthermore, Figure 14 shows that method 1400 may include an operation 1430 to adjust trial variables for a hypothetical stack. After simulation by simulator 1020, the difference between the simulated radar transmission loss value and the measured radar transmission loss value is greater than the threshold, and the corresponding hypothetical stack is not considered to correspond to the radar transmission section of a physical object. In this case, the tuner 1050 in Figure 10 adjusts the trial variables in the form of dielectric constant and thickness values ​​for the hypothetical stack. The tuner 1050 may employ the generalized reduced gradient nonlinear method, LBFGS, L-BFGS-B, or any other preferred method to determine whether to increase or decrease the trial variables. By increasing or decreasing the trial variables, the adjusted hypothetical stack may have a radar transmission loss value close to the measured radar transmission loss value within the RMSE below the threshold, which may be 0.1 dB, 0.01 dB, or 0.001 dB. If the difference between the predicted radar penetration loss value and the measured radar penetration loss value is less than a threshold, the corresponding stack of desired assumptions is considered suitable for modeling the radar-penetrating section of the physical object.

[0096] In addition to adjustment, Figure 14 shows that Method 1400 may include Operation 1440, which performs a computational optimization routine via another simulation system (e.g., Simulation System 1100 in Figure 11). The simulator (e.g., Simulator 1120 in Figure 11) also performs simulations across a desired stack of assumptions and combinations of multiple radar correction layers to generate radar transmission loss values. A comparator (e.g., Comparator 1140 in Figure 11) compares the generated radar transmission loss values ​​to another threshold of the radar compliance requirements, which can be any value, as described throughout this disclosure, but is typically set to a radar transmission loss of 5.0 dB or less, such as ≤3.0 dB, ≤2.0 dB, ≤1.5 dB, 1 dB, or ≤0.5 dB. The comparator then determines that, when one or more specific radar correction layers are combined with a specific section stack, the section stack will have a predicted radar transmission loss value below a desired threshold (e.g., less than 5.0 dB or less than 3.0 dB), and is therefore considered the desired radar correction layer or the optimal radar correction layer.

[0097] After determining the predicted radar correction layer, Figure 14 shows that Method 1400 may include Operation 1450 to provide the end user with one or more desired or predicted radar correction layers. The desired radar correction layer may be displayed on a display screen. The desired radar correction layer may be a set of precise characteristics of a radar correction layer, such as composition, thickness, dielectric constant values, etc., as described herein. Similarly or alternatively, the displayed radar correction layer may be based on the closest match between the predicted radar correction layer and a library of radar correction layers. For example, using data from Table 2, the library may include a set of radar correction layers with preset thicknesses and / or dielectric constants, for example, instead of displaying 500 μm instead of 493 μm, or a set of radar correction layers that differ by thickness in 100 μm increments. Based on the displayed predicted radar correction layer, the end user may select one of the desired radar correction layers (i.e., one of the listed or the closest match), and the engineer / manager / maintenance technician / end user (e.g., end user 130 in Figure 1A or 1B) may apply the selected radar correction layer(s) to the rear of the radar-transparent section of the physical object so that the combination meets the radar compliance requirements.

[0098] This disclosure can also be applied to more conventional facilities in the form of covered buildings, such as auto repair shops. This disclosure (in particular the principles of artificial intelligence) can be further used to identify specific colors, or even the quality of color matching, which may be used in automotive and residential coating matching. Furthermore, this disclosure can be used in recommending potential radar correction layers to make a newly coated section of an object radar-compliant. Thus, it will be understood that the principles of this disclosure can be applied not only to identifying potential candidate colors, but also to measuring radar transmission loss values ​​and verifying the radar compliance of one or more applied radar correction layers to a newly painted section of an object.

[0099] This disclosure may include or utilize a dedicated or general-purpose computer system, which may include, for example, one or more processors and system memory, computer hardware, as will be discussed in more detail below. The scope of this disclosure may also include physical and other computer-readable media for transmitting or storing computer executable instructions and / or data structures. Such computer-readable media may be any available media accessible by a general-purpose or dedicated computer system. A computer-readable medium that stores computer executable instructions and / or data structures is a computer storage medium. A computer-readable medium that transmits computer executable instructions and / or data structures is a transmission medium. Thus, as an example rather than an limitation, this disclosure may include at least two distinctly different types of computer-readable media: computer storage media and transmission media.

[0100] Computer storage media are physical storage media that store computer executable instructions and / or data structures. Physical storage media include computer hardware such as RAM, ROM, EEPROM, solid-state drives ("SSD"), flash memory, phase-change memory ("PCM"), optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, or any other hardware storage devices that can be used to store program code in the form of computer executable instructions or data structures, which can be accessed and executed by a general-purpose or dedicated computer system to perform the functions disclosed in this disclosure.

[0101] A transmission medium may include networks and / or data links that can be used to transmit program code in the form of computer executable instructions or data structures and can be accessed by a general-purpose or dedicated computer system. “Network” is defined as one or more data links that enable the transport of electronic data between computer systems and / or modules and / or other electronic devices. When information is transmitted to or provided to a computer system via a network or another communication connection (either wired, wireless, or a combination of wired and wireless), the computer system may consider the connection to be a transmission medium. The above combinations should also be included within the scope of computer-readable media.

[0102] Furthermore, upon reaching various computer system components, program code in the form of computer executable instructions or data structures can be automatically transmitted from the transmission medium to the computer storage medium (or vice versa). For example, computer executable instructions or data structures received via a network or data link can be buffered in RAM within a network interface module (e.g., a "NIC") and then finally transmitted to the computer system's RAM and / or less volatile computer storage medium within the computer system. Therefore, it should be understood that computer storage medium can be included in computer system components that also (or more primarily) utilize the transmission medium.

[0103] Computer executable instructions include instructions and data that, when executed on one or more processors, cause a general-purpose computer system, a dedicated computer system, or a dedicated processing device to perform a particular function or group of functions. Computer executable instructions can be, for example, binary, intermediate format instructions such as assembly language, or even source code.

[0104] Those skilled in the art will understand that this disclosure can be put into practice in network computing environments having many types of computer system configurations, including personal computers, desktop computers, laptop computers, message processors, handheld devices, multiprocessor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, mobile phones, PDAs, tablets, pagers, routers, switches, and the like. This disclosure can also be put into practice in distributed system environments where both local and remote computer systems, linked through a network (by hardwired data links, wireless data links, or a combination of hardwired and wireless data links), perform tasks. Thus, in a distributed system environment, the computer system may include multiple configured computer systems. In a distributed system environment, program modules may reside in both local and remote memory storage devices.

[0105] Those skilled in the art will also understand that this disclosure can be practiced in a cloud computing environment. While a cloud computing environment can be distributed, this is not required. When distributed, a cloud computing environment may have components that are internationally distributed within an organization and / or owned across multiple organizations. In this specification and the following claims, “cloud computing” is defined as a model for enabling on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services). The definition of “cloud computing” is not limited to any of the many other benefits that can be derived from such a model when properly deployed.

[0106] Cloud computing models can comprise a variety of characteristics, including on-demand self-service, extensive network access, resource pooling, rapid adaptability, and measurement services. Cloud computing models can also manifest in the form of various service models, such as Software as a Service ("SaaS"), Platform as a Service ("PaaS"), and Infrastructure as a Service ("IaaS"). Furthermore, cloud computing models can be deployed using different deployment models, such as private clouds, community clouds, public clouds, and hybrid clouds.

[0107] A cloud computing environment, or cloud computing platform, may comprise a system that includes one or more hosts, each capable of running one or more virtual machines. While in operation, a virtual machine emulates an operating system, and possibly one or more other applications as well. Each host may include a hypervisor that emulates the virtual resources of a virtual machine using physical resources extracted from the virtual machine's appearance. The hypervisor also provides adequate isolation between virtual machines. Thus, from the perspective of any given virtual machine, the hypervisor provides the illusion that the virtual machine is interfaced with physical resources, even though the virtual machine is only interfaced with the appearance of physical resources (e.g., virtual resources). Examples of physical resources include processing power, memory, disk space, network bandwidth, media drives, etc.

[0108] In view of the foregoing, this disclosure can be embodied in several different configurations, as outlined above and further described below in view of the following aspects.

[0109] For example, in a first embodiment, a computer implementation method includes the steps of: receiving a radar transmission loss value in a computer system corresponding to a radar transmission loss measurement of a radar-transparent section of an object, wherein the received radar transmission loss value includes measurements taken from radar signals passing through the radar-transparent section over a frequency range of 1 GHz to 300 GHz; generating a plurality of trial variables in the form of dielectric constant values ​​and thickness values ​​corresponding to a hypothetical radar-transparent section, wherein the hypothetical radar-transparent section includes a hypothetical section stack having a set of associated radar transmission loss values ​​over a frequency range of 1 GHz to 300 GHz; and generating a plurality of trial variables in the form of dielectric constant values ​​and thickness values ​​corresponding to a hypothetical radar-transparent section over a frequency range of 1 GHz to 300 GHz. The method may include the steps of: adjusting one or more trial variables to create a set of predicted radar transmission loss values ​​through a section stack such that the predicted radar transmission loss value versus the measured radar transmission loss value is within a root mean square error (RMSE) of less than 0.1 dB; using the adjusted trial variables, performing a computational optimization routine via a computer system to predict the characteristics of a radar correction layer such that the predicted radar correction layer reduces the predicted radar transmission loss of the assumed stack when added to the assumed section stack to satisfy radar compliance requirements; and generating an output command for displaying the predicted radar correction layer to an end user. In a second embodiment, the computer implementation described in the first embodiment is taken from a frequency range of 60 GHz to 90 GHz.

[0110] In a third embodiment, the computer implementation described in either the preceding first or second embodiment further includes the step of generating an output command, which involves displaying a predicted radar correction layer on a digital display device. In a fourth embodiment, the computer implementation described in any of the preceding first to third embodiments includes a hypothetical radar-transparent section comprising a hypothetical substrate coated with a hypothetical coating layer. In a fifth embodiment, the computer implementation described in the fourth embodiment includes a hypothetical radar-transparent section comprising a hypothetical substrate coated with a plurality of coating layers. In a sixth embodiment, the computer implementation described in any of the preceding first to fifth embodiments includes a hypothetical uncoated substrate. In a seventh embodiment, the computer implementation described in any of the preceding first to sixth embodiments is a vehicle.

[0111] In the eighth aspect, in the computer implementation described in the seventh aspect, the vehicle is an unmanned vehicle or a drone. In the ninth aspect, in the computer implementation described in the preceding first or second aspect, the radar compliance requirement corresponds to an acceptable radar transmission loss threshold of 5 dB or less, such as 3 dB, 2 dB, or 1 dB, within the frequency range of 76 GHz to 81 GHz. In the tenth aspect, in the computer implementation described in any of the preceding first to ninth aspects, the radar compliance requirement corresponds to an acceptable radar transmission loss threshold of 5 dB or less, such as 3 dB, 2 dB, or 1 dB, within the frequency range of 76 GHz to 77 GHz or 77 GHz to 81 GHz. In the eleventh embodiment, a computer implementation of the first to tenth embodiments further comprises the step of displaying an index for one or more predicted sets of radar correction layers that best match a predicted radar correction layer, the index being selected from a separate library of radar correction layers which, when applied to a hypothetical substrate, enable the hypothetical substrate to meet radar compliance requirements.

[0112] In a twelfth aspect, the computer implementation described in the eleventh aspect further includes representing an index for a predicted radar correction layer as a combination of a plurality of separate radar correction layers. In a thirteenth aspect, the computer implementation described in the twelfth aspect, wherein each of the plurality of separate radar correction layers comprises different thicknesses and / or dielectric constants. In a fourteenth aspect, the step of adjusting one or more trial variables in the computer implementation described in any of the preceding first to thirteenth aspects includes adjusting the arrangement of the corresponding hypothetical coating layers around a hypothetical radar-penetrating section. In a fifteenth aspect, the step of adjusting one or more trial variables in the computer implementation described in any of the first to thirteenth aspects includes adjusting either or both of (i) a thickness value and (ii) a dielectric constant value.

[0113] In the 16th aspect, the computer implementation described in any of the preceding 1 to 15 aspects may further include the steps of generating a set of assumed section stacks and generating a predicted radar transmission loss curve for each assumed section stack generated in the set of assumed section stacks, and for each of the set of assumed section stacks, identifying a predicted radar transmission loss curve that fits a radar transmission loss curve corresponding to a measured transmission loss value of less than 0.1 dB, such as less than 0.01 dB or less than 0.001 dB, over a set of measured frequencies. In the 17th aspect, in the computer implementation described in any of the 1 to 16 aspects, the signal is transmitted by a radar transmitter from one side of the radar transmission section to a radar receiver on the opposite side of the vehicle section. In the 18th aspect, in the computer implementation described in any of the 1 to 17 aspects, the signal is transmitted and received on the same side of the radar transmission section.

[0114] In addition to the foregoing, a 19th aspect of the present disclosure includes a computerized method comprising the steps of: curve-fitting a set of measured radar transmission loss values ​​of a radar signal transmitted through a radar transmission section of a vehicle measured over a frequency range in a computer system; and curve-fitting a set of hypothetical radar transmission loss curves over a frequency range for a set of radar transmission loss trials, wherein each radar transmission loss trial represents a set of trial variables in the form of dielectric constant and thickness values ​​corresponding to a set of various hypothetical coating layers arranged around a hypothetical substrate of the hypothetical radar transmission section, and the set of various hypothetical coating layers and the hypothetical substrate are associated with the radar transmission loss over a frequency range. The method includes the steps of: forming a curve-fitting hypothetical section stack having a transmission loss curve; comparing the curve fit of a measured radar transmission curve over a frequency range with any of the hypothetical radar transmission curves over a frequency range to identify the closest match between them so as to be quantified by the root mean square error; performing a computational optimization routine via a computer system to predict the characteristics of a radar correction layer using adjusted trial variables to generate the closest match curve, wherein the calculated radar transmission loss of the hypothetical section stack is reduced when added to the hypothetical section stack to satisfy radar compliance requirements; and displaying the predicted radar correction layer on a digital display device.

[0115] In the 20th embodiment, the computer implementation described in the 20th further includes comparing the measured radar transmission curve with a hypothetical curve to ensure that the root mean square error of the nearest match is between 0 dB and 0.1 dB, such as less than 0.01 dB or less than 0.001 dB.

[0116] Furthermore, a 21st aspect of the present disclosure may include a system having a processor and a computer-readable storage medium thereon, wherein the computer-readable storage medium stores computer-readable instructions thereon, and when executed, the computer-readable instructions to receive, in a computer system, radar transmission loss values ​​corresponding to radar transmission loss measurements of a radar-transparent section of an object, the received radar transmission loss values ​​being measured over a frequency range of 1 to 300, such as 60 GHz to 90 GHz, and to generate a plurality of trial variables in the form of dielectric constant values ​​and thickness values ​​corresponding to a hypothetical radar-transparent section, wherein the hypothetical radar-transparent section has a set of associated radar transmission loss values ​​within a frequency range. The process involves generating a hypothetical section stack, adjusting one or more trial variables to create a set of calculated radar transmission loss values ​​through the hypothetical section stack within a frequency range such that the calculated radar transmission loss value versus the measured radar transmission loss value is within an RMSE of less than 0.1 dB, and using the adjusted trial variables to perform a computational optimization routine via a computer system to predict the characteristics of a radar correction layer such that the predicted radar correction layer reduces the calculated radar transmission loss when added to the hypothetical section stack to meet the compliance requirements of the predicted radar, and providing the output of the predicted radar correction layer to the end user.

[0117] In the 22nd aspect, the system described in the 21st aspect is further configured to send a print command to an additive manufacturing printer, which causes the additive manufacturing printer to print a predicted radar correction layer.

[0118] Furthermore, a 23rd aspect of the present disclosure includes a system comprising a processor and a computer-readable storage medium, wherein the computer-readable storage medium stores computer-readable instructions thereon, and when a computer-readable instruction is executed, the system receives radar transmission loss data over measurement frequencies of 1 to 300 GHz, such as 60 GHz and 90 GHz, for a plurality of arrangements of i) radar-transparent sections of a physical object and ii) one or more calibration layers coated around the radar-transparent sections, wherein the radar-transparent sections comprise a substrate and one or more coating layers coated thereon, and each calibration layer has the same dielectric constant value, and generates a plurality of predicted transmission loss values ​​from a plurality of trial variables in the form of dielectric constant value and thickness value, corresponding to i) a hypothetical section stack and ii) a hypothetical section stack combined with each of the arrangements of one or more calibration layers. The system generates a hypothetical section stack comprising a plurality of hypothetical coating layers applied to a hypothetical substrate of a hypothetical transparent section of a hypothetical object; adjusts one or more trial variables to produce calculated radar transmission loss values ​​for i) the hypothetical section stack and ii) each arrangement of one or more calibration layers and combinations of the hypothetical section stack at the measurement frequency, such that the calculated radar transmission loss value versus the received radar transmission loss value is within a root mean square error of less than 0.1 dB; and performs a computational optimization routine via a computer system to predict the characteristics of a radar correction layer using the adjusted trial variables, such that the predicted radar correction layer reduces the predicted radar transmission loss when added to the hypothetical section stack to meet radar compliance requirements; and provides the output of the predicted radar correction layer to the end user.

[0119] In the 24th aspect, in the system described in the 23rd aspect, the measurement frequency is a single frequency between 60 GHz and 90 GHz. In the 25th aspect, in the system described in the preceding 23rd or 24th aspect, the measurement frequency is a single frequency in the range of 76 GHz to 81 GHz. In the 26th aspect, in the system described in any of the preceding 23rd to 25th aspects, at least one of the arrangements of one or more calibration layers includes a single calibration layer, and at least a second arrangement includes a plurality of single calibration layers stacked together. In the 27th aspect, in the system described in any of the preceding 23rd to 27th aspects, each calibration layer of the plurality of calibration layers has the same dielectric constant, but one calibration layer and the next calibration layer have different thicknesses.

[0120] In addition to the foregoing, 28 aspects of the present disclosure may include a computer implementation method for determining one set of more radar correction layers to address radar transmission loss of a radar-transparent section of an object, the method comprising the steps of receiving radar transmission loss data over measurement frequencies from 1 to 300 GHz, such as 60 GHz and 90 GHz, for i) a radar-transparent section of a physical object and ii) a plurality of arrangements of one or more calibration layers applied around the radar-transparent section, wherein the radar-transparent section comprises a substrate and one or more coating layers applied thereto, and each calibration layer has the same dielectric constant value; and generating a plurality of predicted transmission loss values ​​from a plurality of trial variables in the form of dielectric constant value and thickness value, corresponding to i) a hypothetical section stack and ii) a hypothetical section stack combined with each of the arrangements of one or more calibration layers. The process includes the steps of: generating a section stack comprising a plurality of hypothetical coating layers applied to a hypothetical substrate of a hypothetical transparent section of a hypothetical object; adjusting one or more trial variables to produce calculated radar transmission loss values ​​for i) a hypothetical section stack and ii) each arrangement of one or more calibration layers and combinations of hypothetical section stacks at a measurement frequency, wherein the calculated radar transmission loss value versus the received radar transmission loss value is within a root mean square error of less than 0.1 dB; performing a computational optimization routine via a computer system to predict the characteristics of a radar correction layer using the adjusted trial variables, wherein the predicted radar correction layer reduces the predicted radar transmission loss when added to the hypothetical section stack to meet radar compliance requirements; and providing the output of the predicted radar correction layer to an end user.

[0121] In the 29th aspect, in the computer implementation described in the 28th aspect, the measurement frequency is a single frequency between 60 GHz and 90 GHz. In the 30th aspect, in the computer implementation described in the preceding 28th or 29th aspect, the measurement frequency is a single frequency within the range of 76 GHz to 81 GHz. In the 31st aspect, in the computer implementation described in any of the preceding 28th to 30th aspects, at least one of the arrangements of one or more calibration layers includes a single calibration layer, and at least a second arrangement includes a plurality of single calibration layers stacked together. In the 32nd aspect, in the computer implementation described in any of the preceding 28th to 1st aspects, each calibration layer of the plurality of calibration layers has the same dielectric constant, but one calibration layer and the next calibration layer have different thicknesses.

[0122] In the 33rd embodiment, in any of the preceding 1 to 32 embodiments, the measurement may be performed using a radar transmitter or emitter positioned on one side of the section stack of the object, and a detector or receiver positioned on the opposite side of the section stack. In the 33rd aspect, in any of the preceding 1st to 32nd aspects, trial values ​​for a given assumed section stack may be generated, adjusted and / or optimized using the Transfer Matrix Method (TMM), which calculates or otherwise predicts the electromagnetic plane-wave reflection and transmission characteristics of any given assumed section stack, or even a set of layers within a further given section stack, as outlined, for example, in The Transfer-Matrix Method in Electromagnetics, TGMackay and A. Lakhtakia, Principles of Optics, 7th (expanded) edition, M. Born and E. Wolf, Section 1.6, Handbook of Optics, Chapter 42, “Optical Properties of Films and Coatings”, JADobrowolski, and SJByrnes, “Multilayer Optical Calculations,” the entire contents of these documents are incorporated herein by reference.

[0123] While this subject matter has been described in terms specific to structural features and / or methodological behavior, it should be understood that the subject matter defined in the attached claims is not necessarily limited to the described features or behaviors described above, or the order of the behaviors described above. Rather, the described features and behaviors are disclosed as exemplary forms of implementing the claims.

Claims

1. A computer implementation method, A computer system comprising the steps of receiving a radar transmission loss value corresponding to a radar transmission loss measurement of a radar transmission section of an object, wherein the received radar transmission loss value includes a measurement taken from a radar signal passing through the radar transmission section over a frequency range of 1 GHz to 300 GHz, A step of generating a plurality of trial variables in the form of dielectric constant values ​​and thickness values ​​corresponding to a hypothetical radar-transmitting section, wherein the hypothetical radar-transmitting section includes a hypothetical section stack having a set of associated radar-transmitting loss values ​​within the frequency range of 1 GHz to 300 GHz, A step of adjusting one or more of the trial variables to create a set of predicted radar transmission loss values ​​across the assumed section stack over a frequency range of 1 GHz to 300 GHz, wherein the adjustment step is such that the predicted radar transmission loss value versus the measured radar transmission loss value is within a root mean square error (RMSE) of less than 0.1 dB. A step of performing a computational optimization routine via the computer system to predict the characteristics of the radar correction layer using the adjusted one or more trial variables, wherein the predicted radar correction layer reduces the predicted radar transmission loss of the assumed stack when it is added to the assumed section stack in order to satisfy the radar compliance requirements. A computer implementation method comprising the step of generating an output command for displaying the predicted radar correction layer to an end user.

2. The computer implementation method according to claim 1, wherein the frequency range is taken from 60 GHz to 90 GHz.

3. The computer implementation method according to claim 1 or 2, wherein the step of generating an output command further includes displaying the predicted radar correction layer on a digital display device.

4. The computer-aided method according to any one of claims 1 to 3, wherein the assumed radar-transmitting section includes an assumed uncoated substrate.

5. The computer implementation method according to any one of claims 1 to 4, wherein the object is a vehicle.

6. The computer implementation method according to any one of claims 1 to 5, wherein the radar compliance requirements correspond to acceptable radar transmission loss thresholds of 5 dB or less, such as 3 dB, 2 dB, or 1 dB, within the frequency range of 76 GHz to 81 GHz.

7. The further step includes displaying an index for a predicted set of one or more radar correction layers that best matches the predicted radar correction layer, A computer-aided implementation according to any one of claims 1 to 6, wherein the index is selected from a separate library of radar correction layers that, when applied to the radar-transparent section, enable the radar-transparent section to meet the compliance requirements of the radar.

8. The computer implementation of claim 7, further displaying the indicators for the predicted radar correction layer as a combination of a plurality of separate radar correction layers.

9. The computer-aided implementation according to claim 8, wherein each of the plurality of separate radar correction layers has a different thickness and / or dielectric constant.

10. The computer-aided method according to any one of claims 1 to 9, wherein the step of adjusting one or more trial variables includes adjusting (i) a thickness value and (ii) a dielectric constant value, or both.

11. The steps include generating a section stack of multiple assumptions, and generating a predicted radar transmission loss curve for each section stack of the generated assumptions in the section stack of multiple assumptions, A computer-aided implementation according to any one of claims 1 to 10, further comprising the step of identifying a predicted radar transmission loss curve that fits the measured transmission loss value of less than 0.1 dB, such as RMSE less than 0.01 dB or less than 0.001 dB, over a set of measurement frequencies, for each of the aforementioned set of assumed section stacks.

12. It is a system, The system comprises a processor and a computer-readable storage medium, wherein the computer-readable storage medium stores computer-readable instructions thereon, and when the computer-readable instructions are executed, the system The method involves receiving radar transmission loss data over measurement frequencies of 1 to 300 GHz, such as 60 GHz and 90 GHz, for i) a radar-transparent section of a physical object, and ii) a plurality of arrangements of one or more calibration layers applied around the radar-transparent section, wherein the radar-transparent section comprises a substrate and one or more coating layers applied thereto, and each calibration layer has the same dielectric constant value. To generate a plurality of predicted transmission loss values ​​from a plurality of trial variables in the form of dielectric constant values ​​and thickness values, the predicted transmission loss values ​​corresponding to i) a hypothetical section stack and ii) the hypothetical section stack combined with each of the arrangements of one or more calibration layers, wherein the hypothetical section stack includes a plurality of hypothetical coating layers applied to a hypothetical substrate of a hypothetical transmission section of a hypothetical object. At the measurement frequency, i) for the assumed section stack and ii) for each arrangement of one or more calibration layers and the assumed section stack, one or more of the trial variables are adjusted to produce a calculated radar transmission loss value, such that the calculated radar transmission loss value versus the received radar transmission loss value is within a root mean square error of less than 0.1 dB. Using the adjusted trial variables, perform a computational optimization routine via the computer system, predicting the characteristics of the radar correction layer such that the predicted radar correction layer reduces the predicted radar transmission loss when it is added to the assumed section stack in order to meet the radar compliance requirements. A system that provides the end user with the predicted output of the radar correction layer.

13. The system according to claim 12, wherein the measurement frequency is a single frequency of 60 GHz to 90 GHz, particularly 76 GHz to 81 GHz.

14. The system according to claim 12 or 13, wherein at least one of the arrangements of one or more calibration layers includes a single calibration layer, and at least a second arrangement includes a plurality of the single calibration layers stacked together.

15. The system according to any one of claims 12 to 14, wherein each of the plurality of calibration layers has the same dielectric constant, but one calibration layer has a different thickness from the next calibration layer.

16. A computer implementation method for determining one set of more radar correction layers to address radar transmission loss in the radar transmission section of an object, A step of receiving radar transmission loss data over measurement frequencies from 1 to 300 GHz, such as 60 GHz and 90 GHz, for i) a radar-transmissive section of a physical object and ii) a plurality of arrangements of one or more calibration layers applied around the radar-transmissive section, wherein the radar-transmissive section comprises a substrate and one or more coating layers applied thereto, and each calibration layer has the same dielectric constant value. A step of generating a plurality of predicted transmission loss values ​​from a plurality of trial variables in the form of dielectric constant values ​​and thickness values, the predicted transmission loss values ​​corresponding to i) a hypothetical section stack and ii) the hypothetical section stack combined with each of the arrangements of the one or more calibration layers, wherein the hypothetical section stack includes a plurality of hypothetical coating layers applied to a hypothetical substrate of a hypothetical transmission section of a hypothetical object. A step of adjusting one or more of the trial variables in order to produce a calculated radar transmission loss value for i) the assumed section stack and ii) each arrangement of one or more calibration layers and the assumed section stack at the measurement frequency, such that the calculated radar transmission loss value versus the received radar transmission loss value is within a root mean square error of less than 0.1 dB. A step of performing a computational optimization routine via the computer system using the adjusted trial variables, the step of predicting the characteristics of the radar correction layer such that the predicted radar correction layer reduces the predicted radar transmission loss when it is added to the assumed section stack in order to satisfy the radar compliance requirements, A computer-aided method comprising the step of providing an end user with the predicted output of the radar correction layer.

17. The computer implementation method according to claim 16, wherein the measurement frequency is a single frequency between 60 GHz and 90 GHz.

18. The computer implementation method according to claim 16 or 17, wherein the measurement frequency is a single frequency within the range of 76 GHz to 81 GHz.

19. The computer implementation method according to any one of claims 16 to 18, wherein at least one of the arrangements of one or more calibration layers includes a single calibration layer, and at least a second arrangement includes a plurality of the single calibration layers stacked together.

20. The computer implementation method according to any one of claims 16 to 19, wherein each of the plurality of calibration layers has the same dielectric constant, but one calibration layer has a different thickness from the next calibration layer.

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