A method, device and equipment for simulating radiation transmission of an agricultural strip intercropping structure

Abstract

The application provides a kind of agricultural strip intercropping structure radiation transmission simulation method, device and equipment, it is related to radiation transmission modeling technical field, including: obtaining unmanned aerial vehicle for strip intercropping structure ground measured parameter and multi-angle observation data collected;Determine the basic repeating unit in strip intercropping structure, and based on ground measured parameter and multi-angle observation data, generate the canopy attribute data and light path corresponding to the basic repeating unit under the specified two-dimensional section, the specified two-dimensional section is the plane formed by the strike direction perpendicular to strip intercropping structure as the first coordinate axis, with the vertical direction of strip intercropping structure as the second coordinate axis;Based on canopy attribute data and light path, the basic repeating unit is divided into center homogeneous area and edge heterogeneous area;Radiation transmission simulation is carried out on the center homogeneous area and edge heterogeneous area to obtain the corresponding strip intercropping reflectivity of strip intercropping structure.The application can realize the accurate simulation of high-low crop intercropping structure reflectivity.

Description

Technical Field

[0001] This invention relates to the field of radiation transfer modeling technology, and in particular to a method, apparatus and equipment for simulating radiation transfer in agricultural strip intercropping structures. Background Technology

[0002] Strip intercropping is an agricultural planting pattern that can significantly improve land use efficiency. Monitoring intercropped farmland using satellite or UAV remote sensing data has become an important means of precision agriculture, and establishing accurate radiative transfer models (RTMs) is the physical basis for achieving high-precision canopy reflectivity simulation and parameter inversion. However, existing models have the following limitations when applied to strip intercropping structures: First, traditional one-dimensional models struggle to accommodate the spatial heterogeneity of strip intercropping structures. Existing models (such as PROSAIL) typically rely on the "turbid medium" assumption, idealizing the vegetation canopy as a horizontally uniform continuum. This simplification ignores the unique row structure, crop height differences, and strip configuration specific to intercropping structures, resulting in the model's inability to accurately represent light transmission paths and interception probabilities in non-uniform scenarios, thus causing significant simulation bias.

[0003] Secondly, existing radiative transfer models struggle to characterize complex interspecific radiative feedback mechanisms. While existing geometric optics or hybrid models can handle row structures, they are mostly designed for homogeneous row planting scenarios with a single crop. Strip intercropping involves alternating planting of multiple crops, exhibiting significant interspecific boundary effects. Existing models struggle to quantify the lateral shading of short-stalked crops by taller crops and neglect the multiple scattering feedback effects of photons between different crop strips, thus failing to accurately reconstruct the radiative transfer characteristics of complex populations.

[0004] Finally, general-purpose 3D models suffer from low computational efficiency, making them unsuitable for large-scale applications. Although general-purpose 3D models (such as Monte Carlo simulations) can theoretically handle complex scenes, their parameterization is complex and computation is extremely time-consuming. Due to the failure to utilize the significant strong periodicity characteristics between strips for mathematical simplification, such models face severe computational bottlenecks when dealing with pixel-level simulations or inversions of massive amounts of data, greatly limiting their operational application potential in regional-scale remote sensing monitoring. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method, apparatus and equipment for simulating radiation transmission in agricultural strip intercropping structures, which can achieve accurate simulation of the reflectivity of high and low crop intercropping structures.

[0006] In a first aspect, the present invention provides a method for simulating radiative transfer in agricultural strip intercropping structures, comprising: Acquire ground-measured parameters and multi-angle observation data collected by UAVs for strip intercropping structures; The basic repeating unit in the strip intercropping structure is determined, and based on ground-measured parameters and multi-angle observation data, the canopy attribute data and optical path path corresponding to the basic repeating unit under a specified two-dimensional cross section are generated; wherein, the specified two-dimensional cross section is a plane formed by taking the row direction perpendicular to the strip intercropping structure as the first coordinate axis and the vertical direction of the strip intercropping structure as the second coordinate axis; Based on canopy attribute data and optical path, the basic repeating unit is divided into a central homogeneous region and an edge heterogeneous region; Radiation transfer simulations were performed on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the strip interlacing reflectivity corresponding to the strip interlacing structure.

[0007] In one implementation, based on ground-measured parameters and multi-angle observation data, canopy attribute data and optical path paths corresponding to a basic repeating unit in a specified two-dimensional cross-section are generated, including: For any target point in the basic repeating unit, the crop strip to which the target point belongs is determined based on the coordinate information of the target point under the specified two-dimensional section, and the canopy medium distribution data and canopy height data corresponding to the crop strip are extracted from the ground measured parameters. The canopy medium distribution data and canopy height data are used as the canopy attribute data of the target point. Additionally, the optical path is obtained by projecting multi-angle observation data onto a specified two-dimensional cross section.

[0008] In one implementation, based on canopy attribute data and optical path path, the basic repeating unit is divided into a central homogeneous region and a peripheral heterogeneous region, including: For any target point in the basic repeating unit, based on the geometric position of the target point under the specified two-dimensional section, and combined with the optical path paths of the solar direction and the observation direction, it is determined whether the light rays are truncated across the strips during their passage through the canopy; If the light only affects a single crop type, it is divided into a central homogeneous region; If light rays span two or more crop attribute regions, it is classified as a marginal heterogeneous region.

[0009] In one implementation, radiative transfer simulation is performed on the central homogeneous region and the peripheral heterogeneous region in the basic repeating unit to obtain the interstrip reflectivity corresponding to the interstrip structure, including: The single scattering contribution of the central homogeneous region and the edge heterogeneous region in the basic repeating unit is simulated to obtain the single scattering contribution of the basic repeating unit. Multiple scattering contributions were simulated for the central homogeneous region and the edge heterogeneous region in the basic repeating unit, and the multiple scattering contributions corresponding to the basic repeating unit were obtained. Based on the single scattering contribution and multiple scattering contribution corresponding to each basic repeating unit, the strip interleaving reflectivity corresponding to the strip interleaving structure is determined.

[0010] In one implementation, single-scattering contribution simulations are performed on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the single-scattering contribution corresponding to the basic repeating unit, including: Using the SAIL radiative transfer model, the single radiation contribution of the central homogeneous region is simulated to obtain the single reflectivity of the central homogeneous region. By introducing a heterogeneous bidirectional gap rate formula with a hotspot correction factor, a single radiation simulation of the edge heterogeneous region is performed to obtain the single reflectivity corresponding to the edge heterogeneous region. The single reflectance corresponding to the central homogeneous region and the single reflectance corresponding to the edge heterogeneous region are weighted to obtain the single scattering contribution corresponding to the basic repeating unit.

[0011] In one implementation, by introducing a heterogeneous bidirectional gap rate formula with a hotspot correction factor, a single-pass radiation simulation is performed on the edge heterogeneous region to obtain the single-pass reflectivity corresponding to the edge heterogeneous region, including: For any target point within the edge heterogeneous region, determine whether to introduce a hotspot correction factor based on the direction of the light ray corresponding to that target point; If not, determine the effective geometric optical path length of the optical path within the crop strip to which the target point belongs, and determine the heterogeneous bidirectional gap rate in combination with canopy attribute data; If so, the heterogeneous bidirectional gap ratio is determined based on the hotspot correction factor, the solar direction gap ratio, and the observation direction gap ratio. The single reflectance corresponding to the edge heterogeneous region is determined based on the heterogeneous bidirectional gap ratio.

[0012] In one implementation, multiple scattering contribution simulations are performed on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the multiple scattering contribution corresponding to the basic repeating unit, including: Multiple scattering contribution simulations were performed on the central homogeneous region to obtain the corresponding multiple reflectivity of the central homogeneous region. Based on the uplink and downlink radiation flux densities, the multiple scattering contribution of the edge heterogeneous region is simulated to obtain the multiple reflectivity of the edge heterogeneous region. The multiple reflectance corresponding to the central homogeneous region and the multiple reflectance corresponding to the edge heterogeneous region are weighted to obtain the multiple scattering contribution corresponding to the basic repeating unit.

[0013] Secondly, the present invention also provides a radiation transfer simulation device for agricultural strip intercropping structures, comprising: The data acquisition module is used to acquire ground-measured parameters and multi-angle observation data collected by the UAV for the strip intercropping structure; The data processing module is used to determine the basic repeating unit in the strip intercropping structure, and based on ground-measured parameters and multi-angle observation data, generate the canopy attribute data and optical path path of the basic repeating unit under a specified two-dimensional cross section; wherein, the specified two-dimensional cross section is a plane formed by taking the row direction perpendicular to the strip intercropping structure as the first coordinate axis and the vertical direction of the strip intercropping structure as the second coordinate axis; The region division module is used to divide basic repeating units into central homogeneous regions and peripheral heterogeneous regions based on canopy attribute data and optical path paths; The radiation transfer simulation module is used to simulate the radiation transfer of the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the strip interlacing reflectivity corresponding to the strip interlacing structure.

[0014] Thirdly, the present invention also provides an electronic device including a processor and a memory, the memory storing computer-executable instructions executable by the processor, the processor executing the computer-executable instructions to implement any of the methods provided in the first aspect.

[0015] Fourthly, the present invention also provides a computer-readable storage medium storing computer-executable instructions, which, when invoked and executed by a processor, cause the processor to implement any of the methods provided in the first aspect.

[0016] This invention provides a method, apparatus, and equipment for simulating radiative transfer in agricultural strip intercropping structures. First, ground-based measured parameters and multi-angle observation data collected by an unmanned aerial vehicle (UAV) on the strip intercropping structure are acquired. Then, the basic repeating units in the strip intercropping structure are determined, and based on the ground-based measured parameters and multi-angle observation data, canopy attribute data and optical path paths corresponding to the basic repeating units under a specified two-dimensional cross-section are generated. The specified two-dimensional cross-section is a plane formed by using the row direction perpendicular to the strip intercropping structure as the first coordinate axis and the vertical direction of the strip intercropping structure as the second coordinate axis. Next, based on the canopy attribute data and optical path paths, the basic repeating units are divided into a central homogeneous region and an edge heterogeneous region. Finally, radiative transfer simulation is performed on the central homogeneous region and the edge heterogeneous region in the basic repeating units to obtain the strip intercropping reflectivity corresponding to the strip intercropping structure. The above method constructs basic repeating units of strip intercropping structure, integrates ground measured parameters and multi-angle UAV observation data, accurately generates canopy properties and optical path paths under two-dimensional cross sections, and performs differentiated radiative transmission simulation by distinguishing between central homogeneous regions and edge heterogeneous regions. This invention integrates inter-row scattering and boundary mutual feedback mechanisms, which can achieve accurate simulation of the reflectivity of high and low crop intercropping structures.

[0017] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description and the drawings.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 A flowchart illustrating a radiation transfer simulation method for an agricultural strip intercropping structure provided in an embodiment of the present invention; Figure 2 A technical framework diagram of a radiation transfer simulation method for agricultural strip intercropping structures provided in an embodiment of the present invention; Figure 3 This invention provides a real-world scenario and a scene geometry parameterization diagram of a strip interleaving structure, as provided in an embodiment of the invention. Figure 4 A schematic diagram of the light transmission path between a heterogeneous edge region and a homogeneous center region provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of a radiation transfer simulation device for an agricultural strip intercropping structure provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Currently, existing traditional radiation models suffer from the following problems: they are difficult to adapt to the spatial heterogeneity of strip intercropping structures; they are difficult to characterize complex interspecific radiative feedback mechanisms; and the computational efficiency of general-purpose three-dimensional models is low, making it difficult to support large-scale applications. Therefore, it is particularly important to construct a dedicated radiative transport model for strip intercropping that can take into account horizontal heterogeneity, interspecific feedback mechanisms, and computational efficiency.

[0023] Based on this, in order to address the problems of insufficient structural representation ability and neglect of boundary effects in existing radiative transfer models for strip intercropping structures, this invention provides a method, device and equipment for simulating radiative transfer in agricultural strip intercropping structures. By integrating inter-row scattering and boundary feedback mechanisms, it can achieve accurate simulation of the reflectivity of high and low crop intercropping structures.

[0024] To facilitate understanding of this embodiment, a method for simulating radiative transfer in agricultural strip-intercropping structures disclosed in this invention will first be described in detail. This method is modeled as a radiative transfer model (RTAS, A Radiative Transfer Model for Agricultural Strip-Intercropping Structures). See [link to relevant documentation]. Figure 1 The diagram shows a flow chart of a radiation transfer simulation method for an agricultural strip intercropping structure. The method mainly includes the following steps S102 to S108: Step S102: Obtain ground-measured parameters and multi-angle observation data collected by the UAV for the strip intercropping structure.

[0025] For example, the strip intercropping structure includes corn and soybeans. Ground-measured parameters include: plant height of corn and soybeans, strip width, leaf area index (LAI), leaf angle distribution (LAD), and spectral data (including leaf reflectance and transmittance, and soil reflectance). The spectral data was measured using an ASD (Analytical Spectral Devices) spectrometer. Multi-angle observation data is primarily derived from canopy reflectance obtained at different observation angles using a multispectral UAV (such as the DJI Mavic 3 Multispectral Edition) by varying the tilt of the gimbal. The corresponding geometric parameters (such as solar zenith angle, solar azimuth angle, observation zenith angle, and observation azimuth angle) are determined synchronously using the geographical location, time information, and UAV attitude sensors at the time of data collection.

[0026] Step S104: Determine the basic repeating unit in the strip intercropping structure, and based on the ground measured parameters and multi-angle observation data, generate the canopy attribute data and optical path path corresponding to the basic repeating unit in the specified two-dimensional section.

[0027] A Basic Repeated Unit (BRU) is a structural unit in strip intercropping structures that has minimal periodicity along the direction perpendicular to the crop row (X-axis), and whose horizontal span is equal to the sum of the widths of the two crop strips (i.e., ...). ), and fully contain their respective canopy structures (height) Leaf area density distribution Leaf tilt angle distribution The unit can be extended infinitely along the X-axis to reconstruct the entire strip scene, and its internal geometric and optical properties are sufficient to characterize the spatial heterogeneity and directional response characteristics of the interleaving structure. The two-dimensional section is defined as the plane formed by the row direction perpendicular to the interleaving structure as the first coordinate axis (denoted as the X-axis) and the vertical direction of the interleaving structure as the second coordinate axis (denoted as the Z-axis).

[0028] Step S106: Based on canopy attribute data and optical path, the basic repeating unit is divided into a central homogeneous region and an edge heterogeneous region.

[0029] The Non-Boundary Region (NR) refers to a spatial region within a Basic Repeating Unit (BRU) that meets the following conditions: given the direction of solar incidence and the direction of sensor observation, the light path from the ground surface to the top of the canopy traverses only a single crop type of canopy medium. The Boundary Region (BR) refers to a spatial region within a Basic Repeating Unit (BRU) that meets the following conditions: under the same geometric observation conditions, the light path crosses the interface of adjacent crop strips at least once, resulting in it traversing the canopy medium of two or more crop types.

[0030] Step S108: Perform radiation transfer simulation on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the strip interlacing reflectivity corresponding to the strip interlacing structure.

[0031] In one implementation, the single scattering contribution is decomposed into two parts: a central homogeneous region (NR) and an edge heterogeneous region (BR). The single reflectance is calculated separately for each part, and the single scattering contribution of the basic repeating unit is obtained by weighted calculation. Similarly, the multiple scattering contribution is decomposed into two parts: a central homogeneous region (NR) and an edge heterogeneous region (BR). The multiple reflectance is calculated separately for each part, and the multiple scattering contribution of the basic repeating unit is obtained by weighted calculation. Finally, the interstrip reflectance corresponding to the interstrip structure is obtained based on the single scattering contribution and multiple scattering contribution of each basic repeating unit.

[0032] The radiative transfer simulation method for strip intercropping structures provided in this invention constructs basic repeating units of the strip intercropping structure, integrates ground-measured parameters and multi-angle UAV observation data, accurately generates canopy properties and optical path paths in a two-dimensional cross section, and performs differentiated radiative transfer simulation by distinguishing between the central homogeneous region and the edge heterogeneous region. This invention integrates inter-row scattering and boundary feedback mechanisms, which can achieve accurate simulation of the reflectivity of high and low crop intercropping structures.

[0033] For ease of understanding, this invention provides a specific implementation method for simulating radiation transfer in agricultural strip intercropping structures. See [link to relevant documentation]. Figure 2 The diagram illustrates a technical framework for simulating radiative transfer in agricultural strip intercropping structures, comprising: Step 1, scene parameterization, including defining strip intercropping scene parameters (crop height, width, attributes), constructing basic repeating units (BRUs), and setting the medium distribution function; Step 2, geometric projection analysis, including setting the observation geometric angle, projection dimensionality reduction, and calculating geometric factors; Step 3, region division and boundary delineation, including determining whether rays cross crop boundaries; if so, marking them as edge heterogeneous regions (BR); if not, marking them as central homogeneous regions (NR), and then applying periodic boundary conditions; Step 4, boundary parameter correction, including calculating the heterogeneous bidirectional gap rate and introducing hotspot factors for correction; Step 5, radiative flux solution, including calculating single scattering and multiple scattering; Step 6, model output of strip intercropping reflectance.

[0034] The specific implementation process is as follows: (1) Use UAV multispectral remote sensing and ground synchronous measurement to obtain the key input parameters required for modeling.

[0035] Preferably, a multispectral drone (such as DJI Mavic 3 Multispectral) is used to acquire multi-angle observation images and simultaneously obtain the solar zenith angle, solar azimuth angle and sensor observation geometric parameters; Preferably, the ground-measured parameters include plant height, strip width, leaf area index, leaf tilt angle distribution, leaf reflectance and transmittance, and soil reflectance for corn and soybean.

[0036] (2) For any target point in the basic repeating unit, the crop strip to which the target point belongs is determined based on the coordinate information of the target point under the specified two-dimensional section, and the canopy medium distribution data and canopy height data corresponding to the crop strip are extracted from the ground measured parameters. The canopy medium distribution data and canopy height data are used as the canopy attribute data of the target point.

[0037] In practical applications, such as Figure 3The diagram illustrates a real-world scene and its geometric parameterization. The strip intercropping scene is considered to extend infinitely along the row direction (Y-axis) and modeled as a periodic structure along the perpendicular row direction (X-axis). A basic repeating unit (BRU) is defined, containing two crop strips with widths of [missing information]. The canopy heights are respectively Period length The expression for the canopy medium distribution function is as follows: ; The canopy height function can be expressed as: ; in, Used to characterize coordinates Leaf area density corresponding to crop type (such as corn or soybean) Leaf tilt angle distribution function , express The canopy height corresponding to the crop type at that location, A numerical value representing the canopy height. Integer. This indicates that the basic unit repeats infinitely along the X-axis. Mark the interface between two crops.

[0038] (3) Project the multi-angle observation data onto a specified two-dimensional section to obtain the optical path.

[0039] In practical applications, please refer to [link / reference needed]. Figure 3 A three-dimensional geographic coordinate system is established, and the problem of three-dimensional ray (i.e., multi-angle observation data) transmission is reduced to the X–Z plane for solution through orthogonal projection. The projection parameters are defined as follows: ; ; in, Zenith angle, It is the azimuth angle. For the equivalent slope angle, This is the optical path length conversion factor, which will be used in the subsequent calculation of the heterogeneous gap ratio.

[0040] (4) Based on the geometric position of the target point in the specified two-dimensional section, and combined with the optical path path of the sun direction and the observation direction, determine whether the light rays are cut off across the strips during the process of passing through the canopy; if the light rays only involve a single crop type, it is divided into a central homogeneous region; if the light rays cross two or more crop attribute regions, it is divided into an edge heterogeneous region.

[0041] In practical applications, based on whether the light path crosses the crop strip interface, the basic repeating unit (BRU) is divided into a central homogeneous region (NR) and a peripheral heterogeneous region (BR). In this embodiment of the invention, periodic boundary conditions are used to simulate light transmission across units to accurately characterize the shading effect of tall crops on short crops and interspecific scattering feedback. Preferably, NR is a region where the light path traverses only a single crop canopy, and BR is a region where the light path traverses at least two crop canopies. See also Figure 4 The diagram shows a light transmission path between a heterogeneous edge region and a homogeneous central region, as shown below. Figure 4 As shown in (a), the ray of light from target point P pointing towards the sun ( ), the light rays in the direction of observation ( It only penetrates one crop strip. Therefore, the case shown in (a) is a central homogeneous region (NR); as Figure 4 As shown in (b), the ray of light from target point P pointing towards the sun ( , ), the light rays in the direction of observation ( , ) Penetrate crop strips and Therefore, the situation shown in (b) is a marginal heterogeneous region (BR); as Figure 4 As shown in (c), the ray of light from target point P pointing towards the sun ( , ), the light rays in the direction of observation ( ) Penetrate crop strips and Therefore, the case shown in (c) is a marginal heterogeneous region (BR).

[0042] (5) Perform single scattering contribution simulations on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the single scattering contribution corresponding to the basic repeating unit.

[0043] For the central homogeneous region (NR): The single-emission radiation contribution of the central homogeneous region (NR) is simulated using the SAIL radiative transfer model to obtain the single-emission reflectivity corresponding to the central homogeneous region (NR). In practical applications, the central homogeneous region (NR) is regarded as a uniform canopy, and the SAIL radiative transfer model formula is used for calculation. The SAIL radiative transfer model is a traditional radiative transfer model, which will not be elaborated further in this embodiment of the invention.

[0044] For the edge heterogeneous region (BR): By introducing a heterogeneous bidirectional gap ratio formula with a hotspot correction factor, a single-pass radiation simulation is performed on the edge heterogeneous region (BR) to obtain the corresponding single-pass reflectance. In practical applications, the edge heterogeneous region (BR) considers light passing through two media, and the heterogeneous bidirectional gap ratio formula is used for calculation, combined with the leaf volume density and effective optical path length of the two crops. In this embodiment of the invention, based on the Beer-Lambert law, the transmission attenuation of light in the heterogeneous medium is calculated, and a hotspot correction factor is introduced to correct the heterogeneous bidirectional gap ratio, accurately characterizing the hotspot effect of the canopy. The specific process is as follows: (I) For any target point within the edge heterogeneous region, determine whether to introduce a hotspot correction factor based on the ray direction corresponding to that target point. Where, for example... Figure 4 As shown in (b), the ray of light from target point P pointing towards the sun ( , ), the light rays in the direction of observation ( , (The following text appears to be unrelated and possibly from a different source: "Approximately on the same observation path, this situation requires the introduction of a hotspot correction factor to correct the heterogeneous two-way gap rate; such as...") Figure 4 As shown in (c), the ray of light from target point P pointing towards the sun ( , ), the light rays in the direction of observation ( If they are not on the same observation path, then there is no need to introduce a hotspot correction factor.

[0045] (II) If not, determine the effective geometric path length of the light within the crop strip to which the target point belongs, and determine the heterogeneous bidirectional gap ratio in combination with canopy attribute data.

[0046] In practical applications, the formula for calculating the gap ratio considering the mixing of two crop media is as follows: ; in, Represents the heterogeneous bidirectional gap ratio. Representative crop types, including those mentioned above or (Or it can be referred to as crop 1 or crop 2). It is a geometric projection function, which depends on the leaf tilt angle distribution function of the crop. , Leaf area density, For the ray in the first The 3D effective geometric optical path length within the crop medium.

[0047] (III) If so, the heterogeneous bidirectional gap rate is determined based on the hotspot correction factor, the solar direction gap rate, and the observation direction gap rate.

[0048] In practical applications, the bidirectional gap ratio can be obtained through the hotspot factor. The formula is modified to accurately describe the enhanced backscattering phenomenon based on the relative positions of the sun and the sensor (same side or opposite side): ; in, Represents the heterogeneous bidirectional gap ratio. , These represent the direction of the sun and the direction of observation, respectively. , These represent the solar direction gap rate and the observation direction gap rate, respectively. Hotspot correction factor This is the scattering angle between the direction of the sun and the direction of observation.

[0049] (IV) Determine the single reflectance corresponding to the edge heterogeneous region based on the heterogeneous bidirectional gap ratio. Specifically, the single reflectance corresponding to the edge heterogeneous region can be determined according to the following formula: ; in, It is the XZ cross-sectional length of the edge heterogeneous region. These parameters are determined based on the leaf reflectance and transmittance, and the leaf tilt angle distribution function. represent Leaf area density at that location It is the heterogeneous bidirectional gap ratio of the edge heterogeneous region. Soil reflectance.

[0050] Based on this, the single reflectivity corresponding to the central homogeneous region and the single reflectivity corresponding to the edge heterogeneous region are weighted to obtain the single scattering contribution corresponding to the basic repeating unit. Specifically, the single scattering contribution corresponding to the basic repeating unit can be determined according to the following formula: ; in, The contribution of a single scattering to the basic repeating unit. , These are the XZ cross-sectional lengths of the heterogeneous edge region and the homogeneous central region, respectively. , These are the single reflectances of the heterogeneous edge region and the homogeneous center region, respectively.

[0051] (6) Multiple scattering contributions are simulated for the central homogeneous region and the peripheral heterogeneous region in the basic repeating unit to obtain the multiple scattering contribution corresponding to the basic repeating unit. In this embodiment of the invention, the multiple scattering contribution is decomposed into the sum of vegetation and soil scattering, and is similarly divided into a central homogeneous region (NR) and a central homogeneous region (NR). Preferably, the multiple scattering contribution of the region is calculated by using the numerical integration method of the radiative transfer equation, combined with the uplink and downlink radiative flux densities. The multiple scattering contribution is calculated by weighting the central homogeneous region (NR) and the central homogeneous region (NR). Specifically: For the central homogeneous region (NR): Multiple scattering contribution simulation is performed on the central homogeneous region to obtain the corresponding multiple reflectivity. In practical applications, the central homogeneous region (NR) is regarded as a uniform canopy, and its multiple scattering contribution can also be simulated using traditional methods. This embodiment of the invention will not elaborate further on this.

[0052] For the edge heterogeneous region (BR): Based on the uplink and downlink radiative flux densities, a multiple scattering contribution simulation is performed on the edge heterogeneous region to obtain the corresponding multiple reflectivity. Specifically, the multiple reflectivity of the edge heterogeneous region (BR) is... The calculation formula is shown below: ; in, and Direct sunlight and skylight. and They are respectively height The upward and downward radiation flux densities at the location. and From or Go to The conversion factor.

[0053] The multiple reflectance corresponding to the central homogeneous region and the multiple reflectance corresponding to the edge heterogeneous region are weighted to obtain the multiple scattering contribution of the basic repeating unit. Specifically, the multiple scattering contribution of the basic repeating unit can be determined according to the following formula: ; in, The contribution of multiple scattering to the basic repeating unit. , The XZ cross-sectional length represents the central homogeneous region and the peripheral heterogeneous region. , The multiple reflectance refers to the homogeneous central region and the heterogeneous peripheral region.

[0054] (7) Determine the interstrip reflectivity of the interstrip structure based on the single scattering contribution and multiple scattering contribution corresponding to each basic repeating unit. In one example, the sum of the single scattering contribution and multiple scattering contribution corresponding to each basic repeating unit is taken as the final interstrip reflectivity.

[0055] (8) Model validation and application: The accuracy of the model was verified by combining the strategies of "model comparison" (comparing with the LESS model) and "field verification" (based on multi-angle observation by UAV).

[0056] Preferably, the model accuracy is evaluated using the coefficient of determination (R²), root mean square error (RMSE), and relative root mean square error (RRMSE). The model can be used for spectral simulation of strip intercropping structures, vegetation index inversion, and crop growth monitoring.

[0057] The formula for the verification index is as follows: ; ; ; In the formula The total number of samples, This represents the calculated value from the RTAS model. These represent simulated values ​​from the LESS model or observations from unmanned aerial vehicles (UAVs). Generally speaking, The higher the value and the lower the RMSE and RRMSE, the higher the model accuracy.

[0058] In summary, the embodiments of the present invention have at least the following characteristics: With strong structural expressive power, this invention overcomes the limitations of one-dimensional models: By introducing periodic boundary conditions, it achieves a physical expression of the "step-like" heterogeneous canopy structure of interspecies cropping and its interspecific boundary feedback effects in an analytical model. This effectively overcomes the shortcomings of traditional one-dimensional uniform models in describing row structure and simple linear mixture models in ignoring interspecific shading, significantly improving the model's ability to describe non-uniform canopies.

[0059] High simulation accuracy, comparable to 3D models: The model constructed in this invention exhibits spectral simulation capabilities that are highly consistent with real-world 3D simulation models (such as LESS) in both the red and near-infrared bands. By accurately calculating the visible probability of components and the contribution of multiple scattering within the field of view, the model maintains high simulation accuracy under different solar-observation geometries, making it particularly suitable for remote sensing data analysis under complex observation conditions.

[0060] Significantly improved computational efficiency: Compared to computationally expensive general-purpose 3D models, this invention utilizes the strong periodicity of strip interlacing to mathematically simplify the radiative transfer process. While maintaining simulation accuracy, it significantly reduces computational complexity and time costs, enabling it to meet the needs of rapid forward modeling and parameter inversion of large-scale, high spatiotemporal resolution remote sensing data.

[0061] With a clear mechanism and strong scalability, the RTAS model is based on rigorous geometric optics and radiative transfer theory, with a well-defined physical mechanism. As a forward modeling tool for analyzing radiative transfer in heterogeneous canopies, it provides a solid theoretical basis and an efficient computational kernel for the accurate unmixing and inversion of biophysical parameters (such as leaf area index and chlorophyll content) of strip intercropping structures.

[0062] Based on the foregoing embodiments, this invention provides a radiation transfer simulation device for agricultural strip intercropping structures, see [link to previous embodiment]. Figure 5 The diagram shows a structural schematic of a radiation transfer simulation device for an agricultural strip intercropping structure. The device mainly includes the following parts: Data acquisition module 502 is used to acquire ground-measured parameters and multi-angle observation data collected by UAV for strip intercropping structures; The data processing module 504 is used to determine the basic repeating unit in the strip intercropping structure, and generate the canopy attribute data and optical path path of the basic repeating unit in a specified two-dimensional section based on ground measured parameters and multi-angle observation data; wherein, the specified two-dimensional section is a plane formed by taking the row direction perpendicular to the strip intercropping structure as the first coordinate axis and the vertical direction of the strip intercropping structure as the second coordinate axis. The region division module 506 is used to divide the basic repeating unit into a central homogeneous region and an edge heterogeneous region based on canopy attribute data and optical path. The radiation transfer simulation module 508 is used to simulate the radiation transfer of the central homogeneous region and the edge heterogeneous region in the basic repeating unit in order to obtain the strip interlacing reflectivity corresponding to the strip interlacing structure.

[0063] The radiation transmission simulation device for strip intercropping structures provided in this invention constructs basic repeating units of the strip intercropping structure, integrates ground-measured parameters and multi-angle UAV observation data, accurately generates canopy properties and optical path paths in a two-dimensional cross section, and performs differentiated radiation transmission simulation by distinguishing between the central homogeneous region and the edge heterogeneous region. This invention integrates inter-row scattering and boundary feedback mechanisms, which can achieve accurate simulation of the reflectivity of high and low crop intercropping structures.

[0064] In one implementation, the data processing module 504 is specifically used for: For any target point in the basic repeating unit, the crop strip to which the target point belongs is determined based on the coordinate information of the target point under the specified two-dimensional section, and the canopy medium distribution data and canopy height data corresponding to the crop strip are extracted from the ground measured parameters. The canopy medium distribution data and canopy height data are used as the canopy attribute data of the target point. Additionally, the optical path is obtained by projecting multi-angle observation data onto a specified two-dimensional cross section.

[0065] In one implementation, the region partitioning module 506 is specifically used for: Based on the geometric position of the target point under the specified two-dimensional cross section, and combined with the optical path paths of the sun direction and the observation direction, it is determined whether the light rays are truncated across the strips during their passage through the canopy; If the light only affects a single crop type, it is divided into a central homogeneous region; If light rays span two or more crop attribute regions, it is classified as a marginal heterogeneous region.

[0066] In one embodiment, the radiation transfer simulation module 508 is specifically used for: The single scattering contribution of the central homogeneous region and the edge heterogeneous region in the basic repeating unit is simulated to obtain the single scattering contribution of the basic repeating unit. Multiple scattering contributions were simulated for the central homogeneous region and the edge heterogeneous region in the basic repeating unit, and the multiple scattering contributions corresponding to the basic repeating unit were obtained. Based on the single scattering contribution and multiple scattering contribution corresponding to each basic repeating unit, the strip interleaving reflectivity corresponding to the strip interleaving structure is determined.

[0067] In one embodiment, the radiation transfer simulation module 508 is specifically used for: Using the SAIL radiative transfer model, the single radiation contribution of the central homogeneous region is simulated to obtain the single reflectivity of the central homogeneous region. By introducing a heterogeneous bidirectional gap rate formula with a hotspot correction factor, a single radiation simulation of the edge heterogeneous region is performed to obtain the single reflectivity corresponding to the edge heterogeneous region. The single reflectance corresponding to the central homogeneous region and the single reflectance corresponding to the edge heterogeneous region are weighted to obtain the single scattering contribution corresponding to the basic repeating unit.

[0068] In one embodiment, the radiation transfer simulation module 508 is specifically used for: For any target point within the edge heterogeneous region, determine whether to introduce a hotspot correction factor based on the direction of the light ray corresponding to that target point; If not, determine the effective geometric optical path length of the optical path within the crop strip to which the target point belongs, and determine the heterogeneous bidirectional gap rate in combination with canopy attribute data; If so, the heterogeneous bidirectional gap ratio is determined based on the hotspot correction factor, the solar direction gap ratio, and the observation direction gap ratio. The single reflectance corresponding to the edge heterogeneous region is determined based on the heterogeneous bidirectional gap ratio.

[0069] In one embodiment, the radiation transfer simulation module 508 is specifically used for: Multiple scattering contribution simulations were performed on the central homogeneous region to obtain the corresponding multiple reflectivity of the central homogeneous region. Based on the uplink and downlink radiation flux densities, the multiple scattering contribution of the edge heterogeneous region is simulated to obtain the multiple reflectivity of the edge heterogeneous region. The multiple reflectance corresponding to the central homogeneous region and the multiple reflectance corresponding to the edge heterogeneous region are weighted to obtain the multiple scattering contribution corresponding to the basic repeating unit.

[0070] The device provided in this embodiment of the invention has the same implementation principle and technical effect as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the device embodiment can be referred to the corresponding content in the aforementioned method embodiment.

[0071] This invention provides an electronic device, specifically, the electronic device includes a processor and a memory; the memory stores a computer program, which, when run by the processor, executes the method described in any of the above embodiments.

[0072] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. The electronic device 100 includes: a processor 60, a memory 61, a bus 62, and a communication interface 63. The processor 60, the communication interface 63, and the memory 61 are connected through the bus 62. The processor 60 is used to execute executable modules, such as computer programs, stored in the memory 61.

[0073] The memory 61 may include high-speed random access memory (RAM) or non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 63 (which can be wired or wireless), such as the Internet, wide area network, local area network, metropolitan area network, etc.

[0074] Bus 62 can be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 6 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0075] The memory 61 is used to store programs. After receiving an execution instruction, the processor 60 executes the program. The method executed by the device for defining the flow process disclosed in any of the foregoing embodiments of the present invention can be applied to the processor 60 or implemented by the processor 60.

[0076] Processor 60 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of processor 60 or by instructions in software form. Processor 60 can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this invention can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 61. Processor 60 reads the information in memory 61 and, in conjunction with its hardware, completes the steps of the above method.

[0077] The computer program product of the readable storage medium provided in the embodiments of the present invention includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods described in the foregoing method embodiments. For specific implementation, please refer to the foregoing method embodiments, which will not be repeated here.

[0078] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0079] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for simulating radiative transfer in a strip interleaved structure, characterized in that, include: Acquire ground-measured parameters and multi-angle observation data collected by UAVs for strip intercropping structures; The basic repeating unit in the strip intercropping structure is determined, and based on the measured ground parameters and the multi-angle observation data, the canopy attribute data and optical path path corresponding to the basic repeating unit under a specified two-dimensional cross section are generated; wherein, the specified two-dimensional cross section is a plane formed by taking the row direction perpendicular to the strip intercropping structure as the first coordinate axis and the vertical direction of the strip intercropping structure as the second coordinate axis; Based on the canopy attribute data and the optical path, the basic repeating unit is divided into a central homogeneous region and an edge heterogeneous region; Radiation transfer simulations are performed on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the strip interlacing reflectivity corresponding to the strip interlacing structure.

2. The radiative transfer simulation method for strip interleaved structures according to claim 1, characterized in that, Based on the measured ground parameters and the multi-angle observation data, the canopy attribute data and optical path path corresponding to the basic repeating unit in a specified two-dimensional section are generated, including: For any target point in the basic repeating unit, the crop strip to which the target point belongs is determined based on the coordinate information of the target point under a specified two-dimensional section, and the canopy medium distribution data and canopy height data corresponding to the crop strip are extracted from the ground measured parameters. The canopy medium distribution data and the canopy height data are used as the canopy attribute data of the target point. Furthermore, the optical path is obtained by projecting the multi-angle observation data onto the specified two-dimensional cross section.

3. The radiative transfer simulation method for strip interleaved structures according to claim 2, characterized in that, Based on the canopy attribute data and the optical path, the basic repeating unit is divided into a central homogeneous region and an edge heterogeneous region, including: Based on the geometric position of the target point under the specified two-dimensional cross section, and combined with the optical path paths of the sun direction and the observation direction, it is determined whether the light rays are truncated across the strips during their passage through the canopy; If the light only affects a single crop type, it is divided into a central homogeneous region; If light rays span two or more crop attribute regions, it is classified as a marginal heterogeneous region.

4. The radiative transfer simulation method for strip interleaved structures according to claim 1, characterized in that, Radiation transfer simulations are performed on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the interstrip reflectivity corresponding to the interstrip structure, including: The single scattering contribution of the central homogeneous region and the edge heterogeneous region in the basic repeating unit is simulated to obtain the single scattering contribution corresponding to the basic repeating unit. Multiple scattering contribution simulations were performed on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the multiple scattering contribution corresponding to the basic repeating unit. Based on the single scattering contribution and the multiple scattering contribution corresponding to each of the basic repeating units, the strip interleaving reflectivity corresponding to the strip interleaving structure is determined.

5. The radiative transfer simulation method for interspersed strip structures according to claim 4, characterized in that, Single-scattering contribution simulations were performed on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the single-scattering contribution corresponding to the basic repeating unit, including: Using the SAIL radiative transfer model, the single radiation contribution of the central homogeneous region is simulated to obtain the single reflectivity of the central homogeneous region. By introducing a heterogeneous bidirectional gap rate formula with a hotspot correction factor, a single radiation simulation is performed on the edge heterogeneous region to obtain the single reflectivity corresponding to the edge heterogeneous region. The single reflectance corresponding to the central homogeneous region and the single reflectance corresponding to the edge heterogeneous region are weighted to obtain the single scattering contribution corresponding to the basic repeating unit.

6. The radiative transfer simulation method for strip interleaved structures according to claim 5, characterized in that, By introducing a heterogeneous bidirectional gap rate formula with a hotspot correction factor, a single-pass radiation simulation is performed on the edge heterogeneous region to obtain the single-pass reflectivity corresponding to the edge heterogeneous region, including: For any target point within the edge heterogeneous region, determine whether to introduce a hotspot correction factor based on the direction of the light rays corresponding to the target point; If not, determine the effective geometric optical path length of the optical path within the crop strip to which the target point belongs, and determine the heterogeneous bidirectional gap rate in combination with the canopy attribute data; If so, the heterogeneous bidirectional gap ratio is determined based on the hotspot correction factor, the solar direction gap ratio, and the observation direction gap ratio. The single reflectance corresponding to the edge heterogeneous region is determined based on the heterogeneous bidirectional gap ratio.

7. The method for simulating radiative transfer in a strip interleaved structure according to claim 4, characterized in that, Multiple scattering contribution simulations were performed on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the multiple scattering contribution corresponding to the basic repeating unit, including: Multiple scattering contribution simulations were performed on the central homogeneous region to obtain the multiple reflectivity corresponding to the central homogeneous region. Based on the uplink and downlink radiation flux densities, the multiple scattering contribution of the edge heterogeneous region is simulated to obtain the multiple reflectivity corresponding to the edge heterogeneous region. The multiple reflectance corresponding to the central homogeneous region and the multiple reflectance corresponding to the edge heterogeneous region are weighted to obtain the multiple scattering contribution corresponding to the basic repeating unit.

8. A radiation transfer simulation device for agricultural strip intercropping structures, characterized in that, include: The data acquisition module is used to acquire ground-measured parameters and multi-angle observation data collected by the UAV for the strip intercropping structure; The data processing module is used to determine the basic repeating unit in the strip intercropping structure, and based on the measured ground parameters and the multi-angle observation data, generate the canopy attribute data and optical path path of the basic repeating unit under a specified two-dimensional cross section; wherein, the specified two-dimensional cross section is a plane formed by taking the row direction perpendicular to the strip intercropping structure as the first coordinate axis and the vertical direction of the strip intercropping structure as the second coordinate axis; The region division module is used to divide the basic repeating unit into a central homogeneous region and an edge heterogeneous region based on the canopy attribute data and the optical path. The radiation transfer simulation module is used to perform radiation transfer simulation on the central homogeneous region and the edge heterogeneous region in the basic repeating unit to obtain the strip interlacing reflectivity corresponding to the strip interlacing structure.

9. An electronic device, characterized in that, The method includes a processor and a memory, the memory storing computer-executable instructions executable by the processor, the processor executing the computer-executable instructions to implement the method of any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions that, when invoked and executed by a processor, cause the processor to perform the method according to any one of claims 1 to 7.

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