Point source model for simulating near-field effects from an antenna structure

Abstract

This document describes techniques and systems for generating point source models for simulating near-field effects from an antenna structure. The techniques and systems generate corresponding far-field radiation patterns of active elements of an antenna array and, in some cases, passive elements, based on near-field values extracted from electromagnetic simulations. The far-field radiation patterns account for electromagnetic interactions between the active elements and the antenna structure, which can include passive elements of the antenna array. The techniques and systems output far-field radiation patterns that are valid for simulating electromagnetic interactions between the antenna array and at least one interacting structure using asymptotic numerical methods. Using the described point source models, engineers can quickly and accurately simulate electromagnetic interactions between an antenna array and an interacting structure for various configurations and applications of the antenna array.

Description

Background Art

[0001] Antennas are used to transmit and receive electromagnetic signals in various applications and configurations, such as in radar systems for detecting and tracking objects. An antenna array includes a combination of active and passive elements for transmitting and receiving electromagnetic radiation, and an antenna structure that may include a circuit board, a reflective surface, a ground plane, a radome, or an enclosure. The antenna array is typically located near other structures (e.g., behind a vehicle bumper), and the electromagnetic radiation from the active elements interacts with the antenna array. Antenna structures and interaction structures located within the near-field region of the antenna array have a significant impact on the electromagnetic characteristics and performance of the antenna array.

[0002] To optimize the placement and configuration of antennas for various applications, engineers simulate the antenna array and the interaction structures nearby. To perform these simulations, engineers typically use full-wave simulation methods, which can accurately represent the electromagnetic radiation from the antenna array and the electromagnetic interactions with the antenna structure and the interaction structures. The full-wave simulation method solves a dense grid model generated by the fine details of the antenna structure and the interaction structures. Solving these grid models using the full-wave simulation method requires a large amount of computational resources and time. To avoid these high costs, some engineers use asymptotic numerical methods, which require less computation and time. However, these asymptotic numerical methods cannot simulate the electromagnetic interactions with the antenna structures and the interaction structures located within the near-field region of the active elements. Summary of the Invention <>

[0003] This document describes techniques and systems for generating a point-source model for simulating near-field effects from an antenna structure. The techniques and systems generate corresponding far-field radiation patterns of the active elements of the antenna array and, in some cases, the passive elements, based on near-field values extracted from electromagnetic simulations. The far-field radiation patterns take into account the electromagnetic interactions between the active elements and the antenna structure, which may include the passive elements of the antenna array. The techniques and systems output a far-field radiation pattern that is valid for simulating the electromagnetic interactions between the antenna array and at least one interaction structure using an asymptotic numerical method. Using the described point-source model, engineers can quickly and accurately simulate the electromagnetic interactions between the antenna array and the interaction structures for various configurations and applications of the antenna array.

[0004] For example, this document describes a method for generating a source model of an antenna array. The source model of the antenna array models the active elements and the antenna structure of the antenna array. The described method simulates the electromagnetic radiation field radiated into space by the active elements and the electromagnetic interaction between the radiation field and the antenna structure. The method then extracts at least one near-field value for each active element based on the interaction between the electromagnetic radiation field and the antenna structure. The method uses a near-field to far-field transformation of the extracted near-field values to generate the far-field radiation patterns of the individual active elements. The method outputs the far-field radiation patterns. The far-field radiation patterns are effective in simulating the electromagnetic interaction between the antenna array and the interacting structure using an asymptotic numerical method.

[0005] This document also describes: a computer-readable storage medium having instructions for performing the methods summarized above and other methods described herein; and a system for performing these methods.

[0006] This summary introduces a simplified concept of generating a point source model to simulate near-field effects from an antenna array structure, and generating a point source model to simulate near-field effects from an antenna array structure will be further described in the detailed description and the drawings below. This summary is not intended to identify essential features of the claimed subject matter, nor is it intended to be used to determine the scope of the claimed subject matter.

[0007] BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Details of one or more aspects of a point source model for simulating near-field effects from an antenna array structure are described in this document with reference to the following drawings. Like numerals are generally used throughout the drawings to refer to like features and components:

[0009] Figure 1 An example environment is shown where an antenna simulator models one or more components of an antenna array and generates a point source model for simulating near-field effects from the antenna structure.

[0010] Figure 2 An example interaction simulator is shown that uses the point source model to simulate the electromagnetic interaction between the antenna array and the interacting structure.

[0011] Figure 3 An example antenna simulator is shown that models the active and passive elements of an antenna array and generates a point source model.

[0012] Figure 4 An example method performed by the antenna simulator to generate the point source model is illustrated. DETAILED DESCRIPTION

[0013] OVERVIEW

[0014] This document describes techniques and systems for generating a point source model for simulating near-field effects from an antenna structure. The point source model allows for more accurate and faster simulation of the electromagnetic interactions of an antenna array and interacting structures near the antenna array. The techniques and systems generate a source model that models the active elements of the antenna array and the antenna structure. The antenna structure can include a ground plane, a reflecting surface, a circuit board, passive components, an enclosure, and a radome. These techniques and systems then use the source model to simulate the electromagnetic radiation field that is radiated into space and received by the antenna elements. In the simulation, the antenna structure is modeled at a location within the electromagnetic radiation field of the active elements. The techniques and systems extract at least one near-field value for each of the active elements based on the interaction of the electromagnetic radiation field with the antenna structure. Based on a near-field to far-field transformation of the near-field values, these techniques and systems generate a far-field radiation pattern for each of the active elements and then output the far-field radiation patterns. The techniques and systems can also include far-field radiation patterns for passive components. The far-field radiation patterns are effective for quickly and accurately simulating the electromagnetic interactions between the antenna array and the interacting structures under various configurations and applications of the antenna array.

[0015] Engineers use simulation tools to analyze the performance of antenna arrays in various configurations and applications. Such simulations can utilize full-wave methods or asymptotic numerical methods. Full-wave simulations solve the complete Maxwell's equations without approximating or neglecting electromagnetic field components. In contrast, asymptotic numerical methods describe electromagnetic radiation in terms of rays or ray fields. It approximates the interaction of electromagnetic radiation with structures through reflection, diffraction, etc. Asymptotic numerical methods are typically designed to simulate the electromagnetic interactions with structures placed in the far-field region of an antenna array and cannot easily model structures located in the near-field, such as the antenna structure or the interacting structure.

[0016] As an example, consider a radar device for detecting and tracking objects in a driver assistance system. Automobile manufacturers typically mount the antenna array of such radar devices in close proximity to the vehicle structure (e.g., behind the bumper, headlight, or fender). To determine the performance and optimal location of the radar device, engineers can simulate the electromagnetic interaction between the radar antenna array and the vehicle structure at different locations on a large number of vehicles. Such simulations must account for the complex characteristics of both the antenna structure and the vehicle structure to improve their accuracy. Traditional full-wave simulations create a fine mesh at both the antenna structure and the vehicle structure. Simulating these meshes requires a large amount of computational resources. As engineers run multiple simulations, the resources and time required to run the simulations grow exponentially. In contrast, traditional asymptotic numerical methods are unable to adequately model and simulate the complexity of the antenna structure located within the near-field region of the radar antenna array. Additionally, if engineers use traditional asymptotic numerical methods to simulate the electromagnetic interaction between the radar antenna array and the vehicle structure, the simulation will use an idealized radiation pattern of the active element without considering the electromagnetic interaction with and the reflected radiation from the antenna structure (including passive elements).

[0017] The described point-source model provides a more accurate and computationally efficient technique and system for simulating the electromagnetic interaction between a radar antenna array and a vehicle structure. The technique and system generate a source model of the active elements and the antenna structure of the radar device, which may include passive elements. The technique and system then simulate the electromagnetic radiation field radiated into space by the active elements and extract at least one near-field value for each active element. In some cases, the technique and system also extract at least one near-field value for each passive element. The near-field values account for the interaction of the electromagnetic radiation field with the antenna structure, thus providing a more accurate representation of the electromagnetic characteristics and performance of the radar device. If appropriate, the technique and system generate a far-field radiation pattern from the near-field values of each of the active and passive elements. The technique and system output the far-field radiation pattern, which can be used to simulate the interaction between the radar device and the vehicle structure using asymptotic numerical methods. Thus, the described technique and system generate an accurate far-field representation of the active and passive elements of the radar device. Compared to full-wave simulation methods, the described technique and system reduce the computational cost of simulating the radar device at different locations behind the bumper of a specific vehicle or multiple vehicles. The simulation time for each simulation is reduced from several hours or days to a few tens of minutes. Asymptotic numerical methods can also accurately simulate multilayer interaction structures (e.g., a painted bumper) or multiple interacting structures (e.g., bumper, fog light, license plate) using the described point-source model without incurring a large increase in computational cost.

[0018] The techniques and systems described for generating a point source model for simulating near-field effects from the structure of a radar antenna array are just one example of ways to reduce the computational resources and time required to accurately simulate the interaction between an antenna array and an interacting structure. Other example techniques and systems are described throughout this document. This document now describes example operating environments and example methods.

[0019] Operating Environment

[0020] Figure 1 An example environment 100 is shown where an antenna simulator 110 generates a point source model 142 for an antenna array 104. The antenna array 104 is mounted to or integrated within a vehicle 102. Although shown as a car, the vehicle 102 can represent other types of motor vehicles (e.g., trucks, motorcycles, buses, tractors, semi-trailers, or construction equipment), non-motor vehicles (e.g., bicycles), rail vehicles (e.g., trains), watercraft (e.g., boats), aircraft (e.g., airplanes, helicopters), or spacecraft (e.g., satellites). The antenna array 104 can also be mounted to or integrated within other structures, such as communication network towers, buildings, electronic devices, robotic devices, etc.

[0021] The antenna array 104 can be a planar array that provides high gain and low loss. Planar arrays are well-suited for vehicle integration due to their small size and depth. For example, the antenna array 104 can include one or more patch antenna sub-arrays (e.g., microstrip patch antenna sub-arrays) or slot antenna sub-arrays (e.g., slot waveguide antenna sub-arrays).

[0022] In environment 100, the antenna array 104 is mounted near the front of the vehicle 102 and behind an interacting structure 106. In other implementations, an automaker can mount the antenna array 104 on or near the top, bottom, rear center, rear side, left side, or right side of the vehicle 102. The antenna array 104 is positioned to provide a particular field of view 108 that encompasses an area of interest.

[0023] The antenna array 104 emits electromagnetic radiation by transmitting one or more electromagnetic signals or waveforms via active elements 122. In environment 100, the antenna array 104 is a radar device that can detect and track objects by transmitting one or more radar signals. For example, the antenna array 104 can transmit electromagnetic signals between 100 and 400 gigahertz (GHz), between 4 and 100 GHz, or between approximately 70 and 80 GHz. In other cases, the antenna array 104 can be a fifth-generation (5G) wireless technology antenna, a 60 GHz wireless network antenna, a Ka-band antenna, or a dedicated short-range communication antenna.

[0024] In this implementation, the interaction structure 106 is the front bumper of the vehicle 102. In other cases, the interaction structure 106 can include additional vehicle structures (e.g., license plate, headlight structure, fog light, fender, body panel) or sensors (e.g., ultrasonic sensor, lidar antenna). Generally, the interaction structure 106 is a structure within the field of view 108 of the antenna array 104. More than one interaction structure 106 can be placed within the field of view 108.

[0025] The antenna simulator 110 includes at least one processor 112 and a computer-readable storage medium 114. The computer-readable storage medium 114 includes a memory medium and a storage medium. Application programs and operating systems (not shown) implemented as computer-readable instructions on the computer-readable storage medium 114 can be executed by the processor 112 to provide some or all of the functions described below. In the depicted configuration, the computer-readable storage medium 114 includes a source model 120, an electromagnetic radiation simulator 130, and a point source generator 140. The source model 120, the electromagnetic radiation simulator 130, and the point source generator 140 can be implemented using hardware, software, firmware, or a combination thereof. As further described below, the source model 120, the electromagnetic radiation simulator 130, and the point source generator 140 together enable the antenna simulator 110 to simulate the antenna array 104.

[0026] The point source model 142 generated by the point source generator 140 provides an accurate assessment of the electromagnetic characteristics and performance of the antenna array 104 by considering the influence of the antenna structure 126 on the antenna array 104. To determine the performance and optimal placement of the antenna array 104 within the vehicle 102, the point source model 142 allows engineers to simulate the electromagnetic interaction between the antenna array 104 and the interaction structure 106. Engineers can also use the point source model 142 to quickly and accurately simulate the performance of the antenna array 104 on different vehicles with various interaction structures 106. The antenna simulator 110 is capable of detecting problems in integrating the antenna array 104 onto the vehicle 102 during the design, integration, and testing phases.

[0027] The source model 120 models at least two active elements 122 of the antenna array 104 and the antenna structure 126. The active elements 122 and the antenna structure 126 represent the antenna array 104 and are defined by the electromagnetic characteristics of their respective surfaces and volumes. In the context of this document, an active element 122 refers to an analog antenna element of the antenna array 104 that radiates electromagnetic radiation. For example, the active elements 122 include a subset of the elements in the transmitter of the antenna array 104 that radiate electromagnetic radiation approximately simultaneously. The source model 120 includes N active elements 122, where N represents a positive integer. The active elements 122 can be configured in an array or as individual elements of one or more sub-arrays. For example, the active elements 122 can be the respective patch elements of one or more planar microstrip patch antenna sub-arrays, the respective slot elements of one or more slotted waveguide antenna sub-arrays, or the respective dipole elements of one or more dipole antenna sub-arrays.

[0028] The active elements 122 can each have dimensions such that the interaction structure 106 is placed in the far-field region of each active element 122. Additionally, the antenna array 104 as a whole can have dimensions such that the interaction structure 106 is placed in the near-field region of the antenna array 104. In this case, the antenna simulator 110 accurately represents the active elements 122 by the far-field sources in the point source model 142, while a single far-field source may not be used to accurately represent the interaction between the antenna array 104 and the interaction structure 106.

[0029] In the context of this document, the far-field region of a radiating structure (e.g., active element 122 - N) or a reflecting structure (e.g., passive element 124) is defined by the region where the electromagnetic field is dominated by the radiation field. In the far-field region, the electric field component and the magnetic field component are orthogonal to each other and orthogonal to the propagation direction. The far-field region typically starts at a distance d from the radiating structure or the reflecting structure, where the distance is greater than 2D 2 / λ, where D is the maximum lateral dimension of the radiating structure, and λ is the wavelength of the emitted radiation. The region within a distance d from the radiating structure or the reflecting structure is generally considered to be the near-field region.

[0030] The antenna structure 126 may include the surface of the antenna array 104, a circuit board, a ground plane, a radome, a housing, or other components. The other components may include passive components 124 which, in the context of this document, include the antenna elements of the receiver of the antenna array 104 or the non-radiating elements of the transmitter of the antenna array 104. The passive components 124 receive a reflected version of the radiated electromagnetic field and may include M passive components 124, where M represents a positive integer. The number of active components 122(N) and passive components 124(M) may be the same or different. The number of sub-arrays in the transmitter of the antenna array 104 may also be the same or different from the number of sub-arrays in the receiver. Additionally, the number of individual components within each sub-array may be the same or different.

[0031] The circuit board is a printed circuit board or a similar component on which the active components 122 and the passive components 124 are printed. The ground plane may include a horizontal conductive surface that reflects electromagnetic radiation. The radome may be a dielectric housing placed in front of the active components 122 and the passive components 124 to protect the antenna array 104. The radome may be modeled as including the air between the radome and the active components 122 and the passive components 124. The housing may include a radome or any other protective structure placed in front of the active components 122 and the passive components 124.

[0032] In the case of a patch antenna array, the antenna structure 126 may represent: the ground plane of the antenna array 104, and the dielectric material placed between the ground plane and the respective patch active components 122 and the respective patch passive components 124 of the antenna array 104. In the case of a slot antenna array, the antenna structure 126 may represent a metal slotted electrode layer that includes slots for the active components 122 and the passive components 124. In both cases, the antenna structure 126 may also represent the dielectric radome of the antenna array 104 placed in front of the active components 122 and the passive components 124.

[0033] The components of the antenna structure 126 may reflect the incident radiation in the respective material layers (such as the material layers of the radome and the ground plane). The incident radiation may be a part of the electromagnetic radiation emitted by the active components 122, which is scattered back to the active components 122 and the passive components 124 by other components of the antenna structure 126. The source model 120 models any component or surface of the antenna array 104 (such as an electrode layer or a structure containing the active components 122) that reflects, refracts, deflects, diffracts, or scatters the incident radiation.

[0034] The electromagnetic radiation simulator 130 simulates the electromagnetic radiation field radiated by the active components 122 into space. In particular, the electromagnetic radiation simulator 130 may perform operations that simulate the waveform generation operations performed by the antenna array 104.

[0035] In these simulations, the antenna structure 126 is located within the electromagnetic radiation field of the active element 122. The simulations evaluate the propagation and scattering effects of the electromagnetic radiation field, including interactions with and reflections from the antenna structure 126. The electromagnetic radiation simulator 130 can evaluate the radiation that originates from the active element 122 and returns to the active element 122 within the source model 120.

[0036] The electromagnetic radiation simulator 130 can use any suitable simulation method to simulate the electromagnetic radiation field, such as full-wave simulation methods, boundary element methods, or the method of moments. As described above, the antenna array 104 used in automotive applications can be a planar array, such as a microstrip patch or slot antenna array, and can include a combination of active elements 122. Additionally, the antenna structure 126 is typically characterized by having a complex dielectric or metallic structure in the vicinity of the active element 122. Since the antenna structure 126 is typically placed in the near field of the active element 122, engineers cannot easily model the antenna structure 126 using asymptotic numerical approximations designed for the far field region. Therefore, if simulating the antenna array 104, engineers typically use a full-wave field solver.

[0037] The point source generator 140 then extracts at least one near-field value for each active element 122 based on the interaction of the electromagnetic radiation field with the antenna structure 126. The point source generator 140 uses the near-field values to generate a near-field distribution pattern for each active element 122. Since the electromagnetic radiation simulator 130 simulates the interaction of the electromagnetic radiation field from each active element 122 with the antenna structure 126, the extracted near-field values provide an accurate representation of the electromagnetic radiation performance of each active element 122.

[0038] The point source generator 140 then generates far-field radiation patterns 132 for the active elements 122 respectively. The far-field radiation patterns 132 are based on a near-field to far-field transformation of the near-field values of the respective active elements 122. The near-field to far-field transformation provides an equivalent far-field radiation pattern of the active element 122 based on the extracted near-field values. The antenna simulator 110 can use any known technique or method to perform the near-field to far-field transformation, such as the mode expansion method with planar, cylindrical, or spherical scanning.

[0039] The point source generator 140 outputs a far-field radiation pattern 132 as part of the point source model 142. The far-field radiation pattern 132 is effective in simulating the electromagnetic interaction between the simulated antenna array 104 and at least one interaction structure 106. The far-field radiation pattern 132 provides an accurate point source representation of the radiation pattern of each active element 122, including the electromagnetic effects caused by the interaction of the active element 122 with the antenna structure 126. The far-field radiation pattern 132 can define the direction, number, or intensity of the rays or ray fields emitted from the active element 122. The point source model 142 can be used to simulate the electromagnetic interaction between the antenna array 104 and the interaction structure 106, as described with respect to Figure 2 further described.

[0040] In other cases, the electromagnetic radiation simulator 130 simulates the electromagnetic radiation field radiated into space by the active elements 122, where the active elements 122 represent a subset of the elements in the transmitters of the antenna array 104. The antenna simulator 110 then performs the above operations to generate the point source model 142 for each set of active elements 122 within the transmitter. For example, if the antenna array 104 approximately simultaneously activates half of the elements in the transmitter and then approximately simultaneously activates the other half of the elements in the transmitter, the antenna simulator 110 generates two point source models 142 to simulate the near-field effects from the antenna structure 126.

[0041] Figure 2 An example interaction simulator 210 for simulating the electromagnetic interaction between the simulated antenna array 104 and the interaction structure 106 is shown. As described with respect to Figure 1 The antenna simulator 110 models the active elements 122 of the antenna array 104 and the antenna structure 126 to generate the point source model 142. The interaction simulator 210 simulates the electromagnetic interaction between the far-field radiation pattern 132 of the point source model 142 and the interaction structure 106.

[0042] The interaction simulator 210 includes at least one processor 212 and a computer-readable storage medium 214. The computer-readable storage medium 214 includes a memory medium and a storage medium. An application program and an operating system (not shown), implemented as computer-readable instructions on the computer-readable storage medium 214, can be executed by the processor 212 to provide some or all of the functions described herein, such as the functions of the interaction simulator 210. The processor 212 can be the same component as the processor 112 or a different component included in the same computing system as or a different computing system from the processor 112. Similarly, the computer-readable storage medium 214 can be the same component as the computer-readable storage medium 114 or a different component included in the same computing system as or a different computing system from the computer-readable storage medium 114. The computer-readable storage medium 214 further includes an interaction model 216 that models the interaction structure 106 as an interaction layer 206.

[0043] The interaction simulator 210 loads a point source model 142 including the far-field radiation pattern 132 into the computer-readable storage medium 214. The far-field radiation pattern 132 is used as an equivalent field source in the interaction simulator 210 to simulate the electromagnetic interaction between the antenna array 104 and the interaction structure 106. The far-field radiation pattern 132 represents an excitation source within the interaction simulator 210. The far-field radiation pattern 132 can represent a point source, where the far-field radiation pattern 132 originates from a single infinitesimal source location.

[0044] The interaction simulator 210 performs a simulation of the electromagnetic interaction using an asymptotic numerical method 218. The asymptotic numerical method 218 simulates the far-field radiation pattern 132 as rays or a ray field 220 that propagates in the radiation direction in front of the antenna array 104. Engineers typically use the asymptotic numerical method 218 to simulate scattering problems involving electrically large interaction structures. An electrically large structure is a structure whose size is larger than the wavelength of the electromagnetic radiation. For example, the lateral dimension of the interaction layer 206 is at least ten times the wavelength of the electromagnetic radiation emitted by the antenna array 104. The physical effects of the rays or the ray field 220 at the boundary of the interaction structure 106 are modeled by calculating the equivalent current from the tangential field impinging on the interaction layer 206 and determining the rays reflected, refracted, or transmitted by the interaction layer 206 from the determined equivalent current.

[0045] The asymptotic numerical method 218 can be a ray launching (RL) method, a geometric optics (GO) method, a ray launching geometric optics (RL-GO) method, a physical optics method, a geometric theory of diffraction method, or a physical theory of diffraction method. For example, the interaction simulator 210 can use the shooting and bouncing-rays (SBR) method, which is an RL-GO method. In the SBR method, the electromagnetic radiation incident on the interaction layer 206 is represented by rays traced using geometric optics, and the interaction of each ray with the interaction layer 206 is determined using physical optics by performing an integral covering the interaction of each ray and the surface.

[0046] Engineers can use the interaction simulator 210 to determine the optimal installation position of the antenna array 104 behind the interaction structure 106. For example, engineers can use the interaction simulator 210 to change the attitude (e.g., position, orientation) of the antenna array 104 relative to the interaction structure 106 and simulate the electromagnetic performance of the antenna array 104 for each attitude. Similarly, engineers can use the interaction simulator 210 to verify whether the antenna array 104 meets the pre-described design goals for a specific configuration, such as not exceeding the maximum distortion limit or performance degradation limit.

[0047] Figure 3 An antenna simulator 110 that models active elements 122 and passive elements 124 to generate a point source model 342 for the antenna array 104 is shown. The source model 320 models the antenna structure 326 to include at least the passive element 124, which is included as a passive radiating element in the point source model 342. The antenna structure 326 is similar to the antenna structure 126 but includes additional details.

[0048] Similar to Figure 1 In the example of, the electromagnetic radiation simulator 130 simulates the electromagnetic radiation field radiated into space by the active elements 122 of the source model 320. The point source generator 140 then extracts seven near-field values 324 for each active element 122. The near-field values 324 can include amplitude and phase values. In some cases, the point source generator 140 extracts additional near-field values 324 for each active element 122.

[0049] In this example, the point source generator 140 also extracts seven near-field values 324 for each of the passive elements 124 in the source model 320. As described above, the passive elements 124 can include elements in the receivers of the antenna array 104 or non-radiating elements of the transmitters of the antenna array 104. In the electromagnetic radiation simulator 130, the passive elements 124 can directly and indirectly reflect the electromagnetic radiation field emitted by the active elements 122. The passive elements 124 are typically made of a reflective material that reflects the simulated electromagnetic radiation field. For example, the electromagnetic radiation field radiated into space by the active elements 122 can be reflected away from the radome and subsequently reflected away from the passive elements 124. The passive elements 124 can also directly reflect the electromagnetic radiation field of the active elements 122. As a result, the passive elements 124 act as indirect radiating elements of the antenna array 104. By extracting the near-field values 324 for each receiver element 124, the point source generator 140 takes into account the mutual coupling effect of the passive elements 124 on the electromagnetic characteristics and performance of the antenna array 104. To extract the near-field values 324 of the passive elements 124, engineers do not need to perform an additional simulation of the source model 320 through the electromagnetic radiation simulator 130 because they can extract the near-field values of both the active elements 122 and the passive elements 124 from the same simulation.

[0050] For each of the active elements 122 and the passive elements 124, the point source generator 140 extracts seven near-field values 324 at the extraction points 322 to generate a distribution of phase and amplitude. In other cases, the point source generator 140 can extract a greater or lesser number of near-field values 324. The point source generator 140 can extract the near-field values 324 from the extraction points 322 at various lateral positions within each active element 122 and each passive element 124.

[0051] The point source generator 140 then generates far-field radiation patterns 332 for the active elements 122 and the passive elements 124, respectively. The far-field radiation patterns 332 are generated based on a near-field to far-field transformation of the near-field values 324 of the active elements 122 and the passive elements 124.

[0052] The antenna simulator 110 outputs a point source model 342 that includes the far-field radiation patterns 332 of the active elements 122 and the far-field radiation patterns 332 of the passive elements 124. The point source model 342 provides an accurate representation of the radiation pattern of the antenna array 104, which accounts for the mutual coupling effect of the passive elements 124.

[0053] Example method

[0054] Figure 4Illustrates an example method 400 for generating a point source model 142 of an antenna array 104. Method 400 is shown as a set of operations (or actions) to be performed, but is not necessarily limited to the order or combination of operations shown herein. Additionally, one or more of the operations may be repeated, combined, or reorganized to provide other methods. In the following discussion sections, reference may be made to Figure 1 the environment 100 as well as Figure 2 and Figure 3 the entities detailed in

[0055] for example only. The technology is not limited to being performed by one or more entities.

[0055] At 402, a source model is generated. The source model models at least two active elements and an antenna structure. For example, the antenna simulator 110 generates a source model 120 of the antenna array 104. The source model 120 models at least two active elements 122 and an antenna structure 126 of the antenna array 104. As described above with respect to Figure 1 the antenna structure 126 may include a surface, a circuit board, a ground plane, passive elements 124, a radome, a housing, or other elements of the antenna array 104.

[0056] At 404, the active elements are simulated to radiate an electromagnetic radiation field into space. For example, the electromagnetic radiation simulator 130 simulates the electromagnetic radiation field radiated into space by the active elements 122 of the source model 120, as Figure 1 shown. The antenna structure 126 is modeled at the position within the electromagnetic radiation field of the active elements 122.

[0057] At 406, at least one near-field value is extracted for each active element. The extraction is based on the interaction of the electromagnetic radiation field with the antenna structure. For example, the point source generator 140 extracts at least one near-field value 324 for each active element 122, as Figure 3 shown. Each near-field value 324 is associated with a specific position or extraction point 322 on the associated active element 112. The extraction of the near-field value is based on the interaction of the electromagnetic radiation field with the antenna structure 126.

[0058] Optionally, at 408, at least one near-field value is extracted for each passive element. For example, the point source generator 140 may also extract at least one near-field value 324 for each of the passive elements 124 of the source model 120, as Figure 3 shown. The near-field values 324 correspond to different extraction points 322 within the associated passive element 124.

[0059] At 410, far-field radiation patterns are generated for the active elements. Each of the far-field radiation patterns is generated separately based on a near-field to far-field transformation of the near-field values of the respective active elements. For example, the point source generator 140 generates far-field radiation patterns 332 for the respective active elements 122, as Figure 3 shown. Each of the far-field radiation patterns 332 is generated separately based on a near-field to far-field transformation of the near-field values of the respective active elements 122.

[0060] Optionally, at 412, far-field radiation patterns are generated for the passive elements. Each of the far-field radiation patterns is generated separately based on a near-field to far-field transformation of the near-field values of the respective passive elements. For example, the point source generator 140 generates far-field radiation patterns 332 for the respective passive elements 124, as Figure 3 shown. This can be in response to the point source generator 140 extracting the near-field values 324 for each passive element 124 at 408. Each of the far-field radiation patterns 332 is generated separately based on a near-field to far-field transformation of the near-field values of the passive elements 124.

[0061] At 414, the far-field radiation patterns are output. For example, the point source generator 140 outputs the far-field radiation patterns 332 of the active elements 122 and, if extracted, the far-field radiation patterns 332 of the passive elements 124 as the point source model 342. The far-field radiation patterns 332 of the active elements 122 and the far-field radiation patterns 332 of the passive elements 124 are represented by Figure 3 the point source model 342. The far-field radiation patterns 332 are effective for simulating the electromagnetic interaction between the antenna array 104 and at least one interaction structure 106 using an asymptotic numerical method, as Figure 2 described in. The interaction structure 106 can have dimensions that place it in the near field of the antenna array 104 and the far field of the respective active elements 122. The asymptotic numerical method simulates the far-field radiation patterns 332 as rays or ray fields. The asymptotic numerical method can propagate rays or ray fields in the radiation direction in front of the antenna array 104.

[0062] Examples

[0063] In the following sections, examples are provided.

[0064] Example 1: A method for generating a point source model of an antenna array, comprising: generating a source model that models at least two active elements of the antenna array and the antenna structure of the antenna array; simulating an electromagnetic radiation field radiated into space by the active elements, the simulation being based on the antenna structure modeled at a certain position in the electromagnetic radiation field; extracting at least one near-field value for each active element based on the interaction between the electromagnetic radiation field and the antenna structure; generating a far-field radiation pattern for each active element, the generation being based on a near-field to far-field transformation of the near-field values of the respective active elements; and outputting the far-field radiation pattern, the far-field radiation pattern being effective for simulating the electromagnetic interaction between the antenna array and at least one interacting structure using an asymptotic numerical method that simulates the far-field radiation pattern as a ray or a ray field.

[0065] Example 2: The method of Example 1, wherein the antenna structure of the source model comprises at least one of the surface of the antenna array, the circuit board of the antenna array, the ground plane of the antenna array, the radome of the antenna array, the housing of the antenna array, or the passive elements of the antenna array.

[0066] Example 3: The method of Example 2, wherein the antenna structure comprises: at least two passive elements, and at least one of the surface, the circuit board, the ground plane, the radome, or the housing; the method further comprises: extracting at least one near-field value for each passive element based on the interaction between the electromagnetic radiation field and the antenna structure; and generating a far-field radiation pattern for each passive element respectively, the generation being based on a near-field to far-field transformation of the near-field values of the corresponding passive elements; and wherein the output of the far-field radiation pattern includes outputting the far-field radiation pattern of the active elements and the far-field radiation pattern of the passive elements.

[0067] Example 4: The method of Example 3, wherein the active elements comprise a first subset of the elements in the transmitter of the antenna array, and the other elements in the transmitter comprise a second subset of the elements; wherein the antenna structure comprises the second subset of the elements as passive elements in the source model; and the method further comprises generating another point source model for the antenna array, wherein the second subset of the elements is modeled as active elements in the other source model, and the first subset of the elements is modeled as passive elements in another source model.

[0068] Example 5: The method of Example 3, wherein extracting at least one near-field value of the active elements and at least one near-field value of the passive elements extracts at least seven near-field values for each active element, and at least seven near-field values for each passive element.

[0069] Example 6: The method of Example 1, wherein the active elements comprise patch elements of one or more patch antenna sub-arrays, slot elements of one or more slot antenna sub-arrays, or dipole elements of one or more dipole antenna sub-arrays.

[0070] Example 7: The method of Example 6, wherein the antenna array includes a radar antenna, a fifth-generation (5G) wireless technology antenna, a 60-GHz wireless network antenna, a Ka-band antenna, or a short-range communication antenna.

[0071] Example 8: The method of Example 1, wherein the asymptotic numerical method includes a ray launching method, a geometric optics method, a ray launching geometric optics method, a physical optics method, a geometric theory of diffraction method, or a physical theory of diffraction method.

[0072] Example 9: The method of Example 1, wherein simulating the electromagnetic radiation field radiated into space by the active elements includes performing a full-wave simulation method that solves the complete Maxwell's equations.

[0073] Example 10: The method of Example 1, further comprising: using an asymptotic numerical method to simulate the far-field radiation pattern as rays or a ray field radiated into space; and determining the interaction of the rays or ray field with at least one interaction structure.

[0074] Example 11: A computer-readable storage medium including computer-executable instructions for generating a point-source model for an antenna array, which when executed cause a processor of a computing device to: generate a source model that models at least two active elements of the antenna array and the antenna structure of the antenna array; simulate the electromagnetic radiation field radiated into space by the active elements, the simulation being based on the antenna structure modeled at a position within the electromagnetic radiation field; extract at least one near-field value for each active element based on the interaction of the electromagnetic radiation field with the antenna structure; generate a far-field radiation pattern for each active element, the generation being based on a near-field to far-field transformation of the near-field values of the respective active elements; and output the far-field radiation pattern, the far-field radiation pattern being valid for simulating the electromagnetic interaction between the antenna array and at least one interaction structure using an asymptotic numerical method that simulates the far-field radiation pattern as rays or a ray field.

[0075] Example 12: The computer-readable storage medium of Example 11, wherein the antenna structure of the source model includes at least one of a surface of the antenna array, a circuit board of the antenna array, a ground plane of the antenna array, a radome of the antenna array, a housing of the antenna array, or a passive element of the antenna array.

[0076] Example 13: The computer-readable storage medium of Example 12, wherein: the antenna structure includes: at least two passive elements, and at least one of the surface, circuit board, ground plane, radome, or housing; and the computer-executable instructions, when executed, further cause a processor of the computing device to: extract at least one near-field value for each passive element based on an interaction between an electromagnetic radiation field and the antenna structure; and generate a far-field radiation pattern for each passive element, respectively, the generation being based on a near-field to far-field transformation of the near-field values of the corresponding passive element; and output the far-field radiation pattern of the active element and the far-field radiation pattern of the passive element.

[0077] Example 14: The computer-readable storage medium of Example 13, wherein the computer-executable instructions, when executed, further cause a processor of the computing device to: extract at least seven near-field values for each active element and at least seven near-field values for each passive element.

[0078] Example 15: The computer-readable storage medium of Example 11, wherein the active element includes patch elements of one or more patch antenna subarrays, slot elements of one or more slot antenna subarrays, or dipole elements of one or more dipole antenna subarrays.

[0079] Example 16: The computer-readable storage medium of Example 15, wherein the antenna array includes a radar antenna, a fifth-generation (5G) wireless technology antenna, a 60-GHz wireless network antenna, a Ka-band antenna, or a short-range communication antenna.

[0080] Example 17: The computer-readable storage medium of Example 11, wherein the asymptotic numerical method includes the ray launching method, the geometric optics method, the ray launching geometric optics method, the physical optics method, the geometric theory of diffraction method, or the physical theory of diffraction method.

[0081] Example 18: The computer-readable storage medium of Example 11, wherein the computer-executable instructions, when executed, further cause a processor of the computing device to: execute a full-wave simulation method that solves the complete Maxwell's equations.

[0082] Example 19: The computer-readable storage medium of Example 11, wherein the computer-executable instructions, when executed, further cause a processor of the computing device or another processor of another computing device to: simulate the far-field radiation pattern as rays or a ray field radiated into space using an asymptotic numerical method; and determine an interaction between the rays or ray field and at least one interaction structure.

[0083] Example 20: A system for generating a point source model of an antenna array, comprising: means for generating a source model that models at least two active elements of the antenna array and the antenna structure of the antenna array; means for simulating an electromagnetic radiation field radiated into space by the active elements, the simulation being based on the antenna structure modeled at a position within the electromagnetic radiation field; means for extracting at least one near-field value for each active element based on the interaction between the electromagnetic radiation field and the antenna structure; means for generating a far-field radiation pattern for each active element, the generation being based on a near-field to far-field transformation of the near-field values of the respective active elements; and means for outputting the far-field radiation pattern, the far-field radiation pattern being effective for simulating the electromagnetic interaction between the antenna array and at least one interacting structure using an asymptotic numerical method that simulates the far-field radiation pattern as a ray or a ray field.

[0084] Conclusion

[0085] Although various embodiments of the present disclosure have been described in the foregoing description and illustrated in the accompanying drawings, it should be understood that the present disclosure is not limited thereto, but may be implemented in various ways within the scope of the following claims for practice. From the foregoing description, it will be apparent that various changes may be made without departing from the spirit and scope of the present disclosure as defined by the following claims.

Claims

1. A method for generating a point source model of an antenna array, comprising: Generating a source model that models at least two active elements of the antenna array and an antenna structure of the antenna array, the antenna structure including at least two passive elements and at least one of the following: a surface of the antenna array, a circuit board of the antenna array, a ground plane of the antenna array, a radome of the antenna array, a housing of the antenna array; Simulating an electromagnetic radiation field radiated into space by the active elements, the simulation being based on the antenna structure modeled at a certain position within the electromagnetic radiation field; Extracting at least seven near-field values for each of the active elements and each of the passive elements based on an interaction between the electromagnetic radiation field and the antenna structure; Generating a far-field radiation pattern for each of the active elements and each of the passive elements, the generation being based on a near-field to far-field transformation of the near-field values of the corresponding active element and the corresponding passive element; And Outputting the far-field radiation patterns of the active elements and the passive elements, the far-field radiation patterns being effective for simulating an electromagnetic interaction between the antenna array and at least one interaction structure using an asymptotic numerical method that simulates the far-field radiation patterns as rays or a ray field.

2. The method according to claim 1, characterized in that The antenna structure of the source model further includes the surface of the antenna array, the circuit board of the antenna array, and the radome of the antenna array.

3. The method according to claim 1, It is characterized in that The active elements include a first subset of elements in a transmitter of the antenna array, and the passive elements include a second subset of the elements in the transmitter; The method further includes generating another point source model for the antenna array, wherein the second subset of the elements is modeled as the active elements in the other source model, while the first subset of the elements is modeled as the passive elements in another source model.

4. The method according to claim 1, characterized in that, The active elements include patch elements of one or more patch antenna sub-arrays, slot elements of one or more slot antenna sub-arrays, or dipole elements of one or more dipole antenna sub-arrays.

5. The method according to claim 4, wherein The antenna array includes a radar antenna, a fifth-generation (5G) wireless technology antenna, a 60-GHz wireless network antenna, a Ka-band antenna, or a short-range communication antenna.

6. The method according to claim 1, wherein The asymptotic numerical method includes a ray launching method, a geometric optics method, a ray launching geometric optics method, a physical optics method, a geometric theory of diffraction method, or a physical theory of diffraction method.

7. The method according to claim 1, wherein Simulating the electromagnetic radiation field radiated into space by the active elements includes performing a full-wave simulation method that solves the complete Maxwell's equations.

8. The method according to claim 1, characterized in that, Further comprising: Using the asymptotic numerical method to simulate the far-field radiation patterns as rays or a ray field radiated into space; And Determining an interaction between the rays or the ray field and the at least one interaction structure.

9. A computer-readable storage medium including computer-executable instructions for generating a point source model for an antenna array, the instructions when executed causing a processor of a computing device to: Generate a source model that models at least two active elements of the antenna array and the antenna structure of the antenna array, the antenna structure including at least two passive elements and at least one of the following: the surface of the antenna array, the circuit board of the antenna array, the ground plane of the antenna array, the radome of the antenna array, the housing of the antenna array; Simulate the electromagnetic radiation field radiated into space by the active elements, the simulation being based on the antenna structure modeled at a position within the electromagnetic radiation field; Extract at least seven near-field values for each of the active elements and each of the passive elements based on the interaction between the electromagnetic radiation field and the antenna structure; Generate a far-field radiation pattern for each of the active elements and each of the passive elements, the generation being based on a near-field to far-field transformation of the near-field values of the corresponding active element and the corresponding passive element; And Output the far-field radiation patterns of the active elements and the passive elements, the far-field radiation patterns being effective for simulating the electromagnetic interaction between the antenna array and at least one interaction structure using an asymptotic numerical method that simulates the far-field radiation pattern as a ray or a ray field.

10. The computer-readable storage medium according to claim 9, characterized in that, The antenna structure of the source model further includes the surface of the antenna array, the circuit board of the antenna array, and the radome of the antenna array.

11. The computer-readable storage medium according to claim 9, wherein The active elements include patch elements of one or more patch antenna sub-arrays, slot elements of one or more slot antenna sub-arrays, or dipole elements of one or more dipole antenna sub-arrays.

12. The computer-readable storage medium according to claim 11, wherein The antenna array includes a radar antenna, a fifth-generation (5G) wireless technology antenna, a 60-GHz wireless network antenna, a Ka-band antenna, or a short-range communication antenna.

13. The computer-readable storage medium according to claim 9, wherein The asymptotic numerical method includes the ray launching method, the geometric optics method, the ray launching geometric optics method, the physical optics method, the geometric theory of diffraction method, or the physical theory of diffraction method.

14. The computer-readable storage medium according to claim 9, wherein The computer-executable instructions, when executed, further cause the processor of the computing device to: execute a full-wave simulation method that solves the complete Maxwell's equations.

15. The computer-readable storage medium according to claim 9, wherein The computer-executable instructions, when executed, further cause the processor of the computing device or another processor of another computing device to: Use the asymptotic numerical method to simulate the far-field radiation pattern as a ray or a ray field radiated into space; And Determine the interaction of the ray or the ray field with the at least one interaction structure.

16. A system for generating a point-source model of an antenna array, comprising: Means for generating a source model that models at least two active elements of the antenna array and the antenna structure of the antenna array, the antenna structure including at least two passive elements and at least one of the following: the surface of the antenna array, the circuit board of the antenna array, the ground plane of the antenna array, the radome of the antenna array, the housing of the antenna array; A device for simulating an electromagnetic radiation field radiated into space by the active element, the simulation being based on the antenna structure modeled at a certain position in the electromagnetic radiation field; A device for extracting at least seven near-field values for each active element and each passive element based on the interaction between the electromagnetic radiation field and the antenna structure; A device for generating a far-field radiation pattern for each active element and each passive element respectively, the generation being based on a near-field to far-field transformation of the near-field values of the corresponding active element and the corresponding passive element; And A device for outputting the far-field radiation patterns of the active element and the passive element, the far-field radiation patterns being effective for simulating the electromagnetic interaction between the antenna array and at least one interacting structure using an asymptotic numerical method that simulates the far-field radiation patterns as rays or ray fields.

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