A ray tracing channel modeling method for ultra-large-scale MIMO communications

Abstract

The present invention discloses a ray tracing channel modeling method for very large-scale MIMO communication, comprising: setting a simulation scenario and simulation parameters for very large-scale MIMO communication, calculating the coherence distance of the very large-scale MIMO antenna array, determining the selection interval of antenna units in the MIMO antenna array, and selecting antenna units for simulation; performing ray tracing simulation on the selected antenna units according to the reflection and diffraction propagation mechanism to determine the propagation trajectory of the rays, determining the ray path in combination with the receiving end in the simulation scenario, and screening out non-repeating ray paths from the ray paths; mapping the non-repeating ray paths to unselected antenna units in the MIMO antenna array to determine the ray paths of the unselected antenna units; and obtaining the channel characteristics of all antenna units in the MIMO antenna array to realize the construction of a ray tracing channel model for very large-scale MIMO communication.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communications, and in particular relates to a ray tracing channel modeling method for ultra-large-scale MIMO communications. Background Art

[0002] In the design of 6G wireless communication networks, deterministic and delay-sensitive networks are increasingly demanding high-precision channel state information, driving the need for even higher accuracy in channel models. Ray-tracing (RT) technology, based on high-frequency approximation and consistent diffraction theory, models electromagnetic wave propagation as ray propagation, enabling accurate prediction of wireless signal propagation characteristics. Compared to statistical channel modeling methods, ray tracing, as a deterministic channel modeling method, leverages detailed propagation environment information to calculate the amplitude, delay, departure angle, and arrival angle of each multipath signal, enabling accurate channel characteristics in the time, frequency, and spatial domains.

[0003] Depending on their implementation, ray tracing methods are primarily categorized as the Shooting and Bouncing Ray Method (SBR) and the Image Method (IM). The Shooting and Bouncing Ray Method (SBR) offers faster simulation speeds but relatively lower accuracy. The Image Method, on the other hand, utilizes precise geometric optics calculations, offering higher accuracy but slower simulation speeds. In complex environments, the computational complexity of the Image Method increases exponentially with the number of objects in the scene, making it unsuitable for large-scale, densely populated scenes. In contrast, the Ray Bouncing Method, which uniformly launches a large number of rays at the transmitter and tracks their propagation paths within the scene, has gained wider application in more complex communication environments. By determining the rays that reach the receiver and calculating their propagation paths, the Ray Bouncing Method accurately obtains multipath information and derives precise channel characteristics based on parameters such as the power, delay, and angle of the multipath signals.

[0004] Massive MIMO (VMS) communication is one of the key application scenarios in the 6G era. Its channels exhibit spherical wave characteristics, spatial nonstationarity, channel hardening effects, and angular sparsity. As the complexity of 6G systems increases significantly, various channel characteristics may have a profound impact on system performance. Therefore, ray tracing-based channel models require a comprehensive analysis of these characteristics. However, in VMS MIMO scenarios, the computational complexity of traditional ray tracing models increases exponentially due to the significant increase in the number of antenna elements, significantly extending simulation time. Ray tracing methods face a difficult trade-off between simulation accuracy and computational complexity, making it difficult to efficiently obtain high-precision channel characteristics in VMS MIMO communication scenarios. Therefore, existing ray tracing techniques have significant limitations between computational efficiency and accuracy, and improvements are urgently needed to meet the channel modeling requirements of VMS MIMO communications. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides a ray tracing channel modeling method for very large-scale MIMO communications. Based on the coherence distance, some antenna units are selected for simulation, and a mapping method is used to determine the ray paths of the unselected antenna units. The present invention can greatly simplify the ray tracing simulation of very large-scale MIMO antenna arrays, improve the simulation efficiency, and meet the channel modeling requirements of very large-scale MIMO communication scenarios.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0007] A ray tracing channel modeling method for ultra-large-scale MIMO communications includes the following steps:

[0008] Step S1: setting a simulation scenario and simulation parameters for ultra-large-scale MIMO communication, and calculating the coherence distance of the ultra-large-scale MIMO antenna array;

[0009] Step S2: determining the selection interval of antenna units in the MIMO antenna array based on the coherence distance;

[0010] Step S3: selecting antenna elements for simulation in the MIMO antenna array according to the selected interval;

[0011] Step S4: performing ray tracing simulation on the selected antenna unit according to the reflection and diffraction propagation mechanism to determine the propagation trajectory of the ray, determining the ray path in combination with the receiving end in the simulation scenario, and screening out non-repeated ray paths from the ray paths;

[0012] Step S5: mapping the non-repeated ray paths to unselected antenna elements in the MIMO antenna array to determine the ray paths of the unselected antenna elements;

[0013] Step S6: Obtain the channel characteristics of all antenna units in the MIMO antenna array to implement ray tracing channel model construction for ultra-large-scale MIMO communication.

[0014] Furthermore, setting simulation scenarios and simulation parameters for ultra-large-scale MIMO antenna array communications includes:

[0015] A three-dimensional geometric model of a building or object composed of triangular faces is used as a simulation scene. The locations of a transmitter and a receiver are set within the simulation scene. A very large-scale MIMO antenna array is deployed at the transmitter location. Information about the very large-scale MIMO antenna array is set, including the arrangement of the very large-scale MIMO antenna array, the number of antenna units, and the spacing between antenna units.

[0016] The simulation scene also includes a number of reflection surfaces that reflect the rays emitted by the antenna unit and a number of wedges that diffract the rays emitted by the antenna unit; and upper limits on the reflection order and diffraction order of the rays are set.

[0017] Furthermore, the coherence distance of the ultra-large-scale MIMO antenna array is The calculation process is:

[0018]

[0019] in, is the autocorrelation function of the ultra-large-scale MIMO antenna array.

[0020] Furthermore, the selection interval of the antenna units in the MIMO antenna array is The determination process is:

[0021]

[0022] in, Indicates the distance between adjacent antenna elements in the MIMO antenna array, Indicates rounding down.

[0023] Furthermore, the specific process of step S3 is as follows: OK, In a very large-scale MIMO antenna array with column antenna elements, antenna elements are selected along a straight line in the very large-scale MIMO antenna array according to the selection interval of the antenna elements. The selected antenna elements are expressed as:

[0024]

[0025]

[0026] …

[0027]

[0028] in, n Indicates the selection interval of antenna units, , .

[0029] Furthermore, the selected antenna units are subjected to ray tracing simulation based on the reflection and diffraction propagation mechanism. The specific process of determining the ray path is as follows:

[0030] i. Take the position of each selected antenna unit in the simulation scene as the transmitting end, emit rays to the surrounding area, and record the reflection order and diffraction order of the rays as zero;

[0031] ii. For each ray, when it hits a reflective surface, a reflected ray is generated according to the mirror reflection principle, and the reflection order is increased by one; when it hits a splitter, a diffracted ray is generated according to the consistent diffraction principle, and the diffraction order is increased by one;

[0032] iii. Repeat step ii for the reflected ray and the diffracted ray until the reflection order is equal to the set upper limit of the reflection order or the diffraction order is equal to the set upper limit of the diffraction order, stop propagating the ray, and record the propagation trajectory of the ray;

[0033] iv. Select the propagation trajectory that can reach the receiving end position from the propagation trajectory of all rays as the ray path.

[0034] Furthermore, the process of screening out non-repeated ray paths is as follows: for all ray paths, determine whether the order of objects contacted during the propagation of the ray paths is exactly the same. If they are the same, delete any ray path; otherwise, both ray paths are retained.

[0035] Furthermore, step S5 includes the following sub-steps:

[0036] Step S5.1: For each non-repeated ray path, record all reflecting surfaces and blocking surfaces on the ray path, wherein the blocking surfaces are all object surfaces located between adjacent reflecting surfaces;

[0037] Step S5.2: For each unselected antenna element in the MIMO antenna array, recalculate based on the mirror reflection principle and the consistent diffraction principle to determine all ray propagation trajectories of the unselected antenna element;

[0038] Step S5.3: Obtaining the intersection points of each ray propagation trajectory of the unselected antenna unit with all reflecting surfaces on each non-repeated ray path and all blocking surfaces on each non-repeated ray path;

[0039] Step S5.4: For each non-repetitive ray path, if the intersection points of the ray propagation trajectory with all the reflecting surfaces on the non-repetitive ray path are all located within the corresponding reflecting surfaces, and the intersection points with all the blocking surfaces on the non-repetitive ray path are all located outside the corresponding blocking surfaces, then the ray propagation trajectory is used as the ray path of the unselected antenna unit.

[0040] Furthermore, step S6 includes the following sub-steps:

[0041] Step S6.1: Calculate the time delay and angle information of each ray path based on all ray paths of each antenna element in the MIMO antenna array;

[0042] Step S6.2: Calculate the electric field at the receiving end of the simulation scenario based on all ray paths of each antenna element in the MIMO antenna array to determine the received power of the antenna element;

[0043] Step S6.3: Use the time delay, angle information, and received power corresponding to all antenna units in the MIMO antenna array as the channel characteristics of the ultra-large-scale MIMO communication scenario to realize the construction of a ray tracing channel model for ultra-large-scale MIMO communication.

[0044] Furthermore, the electric field of the antenna unit at the receiving end of the simulation scene is obtained by accumulating the electric fields of all ray paths of the antenna unit at the receiving end of the simulation scene, wherein the calculation process of the electric field of each ray path at the receiving end of the simulation scene is:

[0045]

[0046] in, is the electric field of a certain ray path in the antenna unit at the receiving end of the simulation scene, is the electric field of the emitted ray corresponding to the ray path, is the total number of reflections, is the ray number in the ray path The reflection coefficient matrix of the secondary reflection, is the wave number, is the propagation distance of the ray path, Is an imaginary unit.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] The present invention's ray tracing channel modeling method for ultra-large-scale MIMO communications targets ultra-large-scale MIMO antenna arrays, selects some antenna units for ray tracing simulation based on coherence distance, and ignores other antenna units, which can significantly simplify the ray tracing simulation steps and improve simulation efficiency. Furthermore, for unselected antenna units, the ray paths of the unselected antenna units are determined by utilizing the intersection relationship between their ray propagation trajectories and all reflection surfaces and blocking surfaces of the non-repeated ray paths in the selected antenna units. The ray paths of the selected antenna units are accurately mapped onto the unselected antenna units, thereby ensuring the rationality and accuracy of the ray path acquisition of the unselected antenna units and the simulation accuracy of ray tracing in ultra-large-scale MIMO communication scenarios. The present invention can construct a ray tracing channel model for ultra-large-scale MIMO communication scenarios, obtain accurate channel characteristics with extremely low simulation complexity, and meet the channel modeling requirements of ultra-large-scale MIMO communication scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a flow chart of the ray tracing channel modeling method for ultra-large-scale MIMO communications according to the present invention;

[0050] Figure 2 Schematic diagram of the simulation scene;

[0051] Figure 3 A received power coverage diagram of a MIMO antenna array using the ray tracing channel modeling method for ultra-large-scale MIMO communications of the present invention;

[0052] Figure 4 This is a diagram showing the power spectrum of the azimuth angle of arrival of a MIMO antenna array using the ray tracing channel modeling method for ultra-large-scale MIMO communications of the present invention;

[0053] Figure 5 This is a diagram of the power spectrum result of the elevation angle of arrival of the MIMO antenna array using the ray tracing channel modeling method for ultra-large-scale MIMO communication of the present invention. DETAILED DESCRIPTION

[0054] The technical solution of the present invention will be further explained below with reference to the accompanying drawings.

[0055] like Figure 1 This is a flow chart of a ray tracing channel modeling method for ultra-large-scale MIMO communication according to the present invention. The ray tracing channel modeling method includes the following steps: Step S1: Setting a simulation scenario and simulation parameters for ultra-large-scale MIMO communication, including:

[0056] A three-dimensional geometric model of a building or object composed of triangular faces is used as a simulation scene. A receiver is set up within the simulation scene, and a very large-scale MIMO antenna array is deployed. The very large-scale MIMO antenna array is used as the transmitter. The position of each antenna element in the very large-scale MIMO antenna array and the position of the receiver are recorded. Information about the very large-scale MIMO antenna array is set, including the arrangement of the very large-scale MIMO antenna array, the number of antenna elements, and the spacing between antenna elements.

[0057] The simulation scenario also includes several reflective surfaces that reflect the rays emitted by the antenna unit and several splitters that diffract the rays emitted by the antenna unit; and sets upper limits on the reflection order and diffraction order of the rays. The reflection order and diffraction order upper limits respectively determine the upper limits of the number of reflections and diffractions of the rays during the propagation process.

[0058] Calculate the coherence distance of the ultra-large-scale MIMO antenna array based on the simulation scenario and the information of the MIMO antenna array:

[0059]

[0060] in, is the autocorrelation function of the ultra-large-scale MIMO antenna array.

[0061] Step S2: When the spacing between antenna units is less than the coherence distance, the ray paths of the antenna units are highly similar and there is no need for repeated simulation. Therefore, the selection interval of the antenna units in the MIMO antenna array is determined based on the coherence distance, and some antenna units with large ray path differences are selected for simulation, which can greatly reduce the complexity of the simulation.

[0062] Selection interval of antenna units in the MIMO antenna array of the present invention The calculation process is:

[0063]

[0064] in, Indicates the distance between adjacent antenna elements in the MIMO antenna array, Indicates rounding down.

[0065] Step S3: Select antenna elements for simulation in the MIMO antenna array according to the selected interval; specifically, for the antenna elements including OK, In a very large-scale MIMO antenna array with column antenna elements, antenna elements are selected along a straight line in the very large-scale MIMO antenna array according to the selection interval of the antenna elements. The selected antenna elements are expressed as:

[0066]

[0067]

[0068] …

[0069]

[0070] in, n Indicates the selection interval of antenna units, , .

[0071] Step S4: Perform ray tracing simulation on the selected antenna units based on the reflection and diffraction propagation mechanism to determine the propagation trajectory of the ray. Combined with the receiving end in the simulation scenario, the ray path is determined. Selecting only some antenna units for ray tracing simulation can greatly simplify the ray tracing simulation steps and improve simulation efficiency. In addition, repeated ray paths contain redundant information, which will lead to a decrease in subsequent simulation efficiency. Therefore, it is necessary to filter out non-repeated ray paths from the ray paths, including the following sub-steps:

[0072] Step S4.1: Take each selected antenna unit in the simulation scenario as the transmitting end and emit rays to the surrounding area. The directions of these rays are evenly distributed on the unit sphere surrounding the transmitting end, and the reflection order and diffraction order of the rays are both recorded as zero;

[0073] Step S4.2: For each ray, when the ray hits the reflective surface, a reflected ray is generated according to the mirror reflection principle, and the reflection order is increased by one; when the ray hits the wedge, a diffracted ray is generated according to the consistent diffraction principle, and the diffraction order is increased by one;

[0074] Step S4.3: Repeat step S4.2 for the reflected ray and the diffracted ray until the reflection order is equal to the set upper limit of the reflection order or the diffraction order is equal to the set upper limit of the diffraction order, then stop propagating the ray and record the propagation trajectory of the ray;

[0075] Step S4.4: Select the propagation trajectory that can reach the receiving end position from the propagation trajectory of all rays as the ray path;

[0076] Step S4.5: For all ray paths, determine whether the order of objects contacted by the ray paths during propagation is exactly the same. If they are the same, it means that the two ray paths are repeated, and any ray path is deleted; otherwise, it means that the two ray paths are different, and both ray paths are retained.

[0077] Step S5: Mapping non-repeated ray paths to unselected antenna elements in the MIMO antenna array and determining the ray paths of the unselected antenna elements can accurately obtain the ray paths of all antenna elements, ensuring the accuracy of the simulated channel characteristics. This includes the following sub-steps:

[0078] Step S5.1: For each non-repeated ray path, record all reflecting surfaces and blocking surfaces on the ray path, where blocking surfaces are all object surfaces located between adjacent reflecting surfaces;

[0079] Step S5.2: For each unselected antenna element in the MIMO antenna array, recalculate the ray propagation trajectories based on the mirror reflection principle and the consistent diffraction principle. No collision judgment is required, and all ray propagation trajectories of the unselected antenna elements can be quickly determined.

[0080] Step S5.3: Obtain the intersection points of each ray propagation trajectory of the unselected antenna unit with all the reflection surfaces on each non-repeated ray path and the intersection points with all the blocking surfaces on each non-repeated ray path;

[0081] Step S5.4: For each non-repeating ray path, if the intersection of the ray propagation trajectory with all reflecting surfaces on the non-repeating ray path lies within the corresponding reflecting surface, and the intersection of the ray propagation trajectory with all blocking surfaces on the non-repeating ray path lies outside the corresponding blocking surface, then the ray propagation trajectory is used as the ray path of the unselected antenna element. Reflecting surfaces and blocking surfaces are objects in the simulation scene that may affect the ray propagation trajectory. By selecting reflecting surfaces and blocking surfaces rather than all objects in the scene for calculation of the ray propagation trajectory, the determination can be completed quickly while ensuring accuracy.

[0082] For the unselected antenna units, the ray paths of the unselected antenna units are determined by utilizing the intersection relationship between their ray propagation trajectories and all reflection surfaces and blocking surfaces of the non-repeated ray paths in the selected antenna units. The ray paths of the selected antenna units are accurately mapped to the unselected antenna units, thereby ensuring the rationality and accuracy of the ray path acquisition of the unselected antenna units and the simulation accuracy of ray tracing in ultra-large-scale MIMO communication scenarios.

[0083] Step S6: Obtaining the channel characteristics of all antenna elements in the MIMO antenna array to implement ray tracing channel model construction for ultra-large-scale MIMO communication, including the following sub-steps:

[0084] Step S6.1: Calculate the time delay and angle information of each ray path based on all ray paths of each antenna element in the MIMO antenna array:

[0085]

[0086]

[0087]

[0088] in, is the time delay of the ray path, is the total length of the ray path, is the speed of light, which is 299792458 m / s; is the azimuth angle of the ray path, is the pitch angle of the ray path, is the unit vector of the ray path corresponding to the emission direction;

[0089] Step S6.2: Calculate the electric field at the receiving end of the simulation scenario based on all ray paths of each antenna element in the MIMO antenna array to determine the received power of the antenna element; wherein the electric field of the antenna element at the receiving end of the simulation scenario is obtained by summing the electric fields of all ray paths of the antenna element at the receiving end of the simulation scenario, wherein the calculation process of the electric field of each ray path at the receiving end of the simulation scenario is:

[0090]

[0091] in, is the electric field of a certain ray path in the antenna unit at the receiving end of the simulation scene, is the electric field of the emitted ray corresponding to the ray path, is the total number of reflections, is the ray number in the ray path The reflection coefficient matrix of the secondary reflection, is the wave number, which can be calculated from the simulation frequency, , Indicates the set simulation frequency; is the propagation distance of the ray path, Is an imaginary unit.

[0092] Step S6.3: Use the time delay, angle information, and received power corresponding to all antenna units in the MIMO antenna array as the channel characteristics of the ultra-large-scale MIMO communication scenario to realize the construction of a ray tracing channel model for ultra-large-scale MIMO communication.

[0093] The ray tracing channel modeling method for ultra-large-scale MIMO communication of the present invention can construct a ray tracing channel model for ultra-large-scale MIMO communication scenarios, obtain accurate channel characteristics with extremely low simulation complexity, and meet the channel modeling requirements of ultra-large-scale MIMO communication scenarios.

[0094] Example

[0095] As Figure 2As an example of the urban scene simulation, the transmitter position and receiver range are set, the simulation frequency is set to 5.3GHz, the ultra-large-scale MIMO antenna array is used as the transmitter, and the size of the ultra-large-scale MIMO antenna array is set to , contains a total of 1024 antenna units, the antenna unit interval is 0.0339 m, and the upper limit of the reflection order of the antenna unit is set to 5, that is, the ray propagates in the scene and experiences a maximum of 5 reflections.

[0096] According to the simulation scenario, the coherence distance is 0.1 m, so the antenna selection interval is calculated. , that is, one out of every four antenna elements is selected for simulation; according to the antenna selection interval, a total of 64 antenna elements are selected, and the rows and columns of the selected antenna elements are expressed as:

[0097]

[0098]

[0099] Perform ray tracing simulation on the selected antenna units based on the reflection and diffraction propagation mechanism to determine the propagation trajectory of the ray. Combined with the receiving end in the simulation scenario, the ray path is determined and non-repeated ray paths are screened out from the ray paths.

[0100] Mapping non-repeated ray paths to unselected antenna elements in the MIMO antenna array to determine ray paths of the unselected antenna elements;

[0101] Obtain the channel characteristics of all antenna elements in the MIMO antenna array and implement ray tracing channel model construction for ultra-large-scale MIMO communications.

[0102] Figure 3 The simulation results of the MIMO antenna array receiving power under this embodiment are shown, and the power coverage in the urban outdoor simulation scenario is given. It can be seen that the power coverage intensity of the receiving end close to the transmitting end is high, and the power coverage intensity of the receiving end far away is low. The receiving end located on the back of the building is blocked, as shown in the dark blue area in the upper left corner of the figure, and the power coverage intensity is very low. Compared with the traditional ray tracing method, the power coverage error simulated by the ray tracing channel modeling method of the present invention is smaller, with an average error of less than 5 dB. Figure 4The result diagram of the arrival azimuth angle power spectrum of the MIMO antenna array under this embodiment is shown, where red represents the arrival azimuth angle power of high received power, and blue represents the arrival azimuth angle power of low received power. It can be seen that the arrival azimuth angle power shows periodic fluctuations along the antenna index, indicating that the ray path angles generated by different antenna units are different. This is a characteristic presented under the conditions of spherical wave propagation, which reflects the spherical wave characteristics presented by the ultra-large-scale MIMO channel, indicating that the ray tracing channel modeling method of the present invention can support ultra-large-scale MIMO communication scenarios. Figure 5 The resulting diagram of the arrival elevation angle power spectrum of the MIMO antenna array under this embodiment is shown, where red represents the arrival elevation angle power of high received power, and blue represents the arrival elevation angle power of low received power. It can be seen that the arrival elevation angle power shows a birth and death effect along the antenna index, which means that the ray paths corresponding to some antenna units are blocked, reflecting the spatial non-stationary characteristics of the ultra-large-scale MIMO channel, and indicating that the present invention can support ultra-large-scale MIMO communication scenarios.

[0103] In one technical solution of the present invention, a computer-readable storage medium is further provided, storing a computer program, wherein the computer program enables a computer to execute a ray tracing channel modeling method for ultra-large-scale MIMO communications.

[0104] In one technical solution of the present invention, an electronic device is also provided, including: a memory, a processor, and a computer program stored in the memory and runnable on the processor. When the processor executes the computer program, a ray tracing channel modeling method for ultra-large-scale MIMO communication is implemented.

[0105] In the embodiments disclosed herein, computer storage media may be tangible media that may contain or store programs for use by or in conjunction with an instruction execution system, apparatus, or device. Computer storage media may include, but are not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any suitable combination of the foregoing. More specific examples of computer storage media may include electrical connections based on one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), optical fibers, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0106] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in this application can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0107] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions based on the principles of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A ray tracing channel modeling method for ultra-large-scale MIMO communications, characterized in that: The steps include: Step S1: setting a simulation scenario and simulation parameters for ultra-large-scale MIMO communication and calculating the coherence distance of the MIMO antenna array; Step S2: determining the selection interval of antenna units in the MIMO antenna array based on the coherence distance; Step S3: selecting antenna elements for simulation in the MIMO antenna array according to the selected interval; Step S4: performing ray tracing simulation on the selected antenna unit according to the reflection and diffraction propagation mechanism to determine the propagation trajectory of the ray, determining the ray path in combination with the receiving end in the simulation scenario, and screening out non-repeated ray paths from the ray paths; Step S5: Mapping non-repeated ray paths to unselected antenna elements in the MIMO antenna array to determine the ray paths of the unselected antenna elements; including the following sub-steps: Step S5.1: For each non-repeated ray path, record all reflecting surfaces and blocking surfaces on the ray path, wherein the blocking surfaces are all object surfaces located between adjacent reflecting surfaces; Step S5.2: For each unselected antenna element in the MIMO antenna array, recalculate based on the mirror image principle and the consistent diffraction principle to determine all ray propagation trajectories of the unselected antenna element; Step S5.3: Obtaining the intersection points of each ray propagation trajectory of the unselected antenna unit with all reflecting surfaces on each non-repeated ray path and all blocking surfaces on each non-repeated ray path; Step S5.4: For each non-repeating ray path, if the intersection points of the ray propagation trajectory with all the reflecting surfaces on the non-repeating ray path are all located within the corresponding reflecting surfaces, and the intersection points of the ray propagation trajectory with all the blocking surfaces on the non-repeating ray path are all located outside the corresponding blocking surfaces, then the ray propagation trajectory is used as the ray path of the unselected antenna unit; Step S6: Obtain the channel characteristics of all antenna units in the MIMO antenna array to implement ray tracing channel model construction for ultra-large-scale MIMO communication.

2. The ray tracing channel modeling method for ultra-large-scale MIMO communication according to claim 1, characterized in that: Setting up the simulation scenario and parameters for ultra-large-scale MIMO antenna array communications includes: A three-dimensional geometric model of a building or object composed of triangular faces is used as a simulation scene. The locations of a transmitter and a receiver are set within the simulation scene. A very large-scale MIMO antenna array is deployed at the transmitter location. Information about the very large-scale MIMO antenna array is set, including the arrangement of the very large-scale MIMO antenna array, the number of antenna units, and the spacing between antenna units. The simulation scene also includes a number of reflection surfaces that reflect the rays emitted by the antenna unit and a number of wedges that diffract the rays emitted by the antenna unit; and upper limits on the reflection order and diffraction order of the rays are set.

3. The ray tracing channel modeling method for ultra-large-scale MIMO communication according to claim 1, characterized in that: The coherence distance of the MIMO antenna array The calculation process is: in, is the autocorrelation function of the ultra-large-scale MIMO antenna array.

4. The ray tracing channel modeling method for ultra-large-scale MIMO communication according to claim 3, characterized in that: Selection interval of antenna units in the MIMO antenna array The determination process is: in, Indicates the distance between adjacent antenna elements in the MIMO antenna array, Indicates rounding down.

5. The ray tracing channel modeling method for ultra-large-scale MIMO communication according to claim 1, characterized in that: The specific process of step S3 is as follows: OK, In a very large-scale MIMO antenna array with column antenna elements, antenna elements are selected along a straight line in the very large-scale MIMO antenna array according to the selection interval of the antenna elements. The selected antenna elements are expressed as: … in, n Indicates the selection interval of antenna units, , .

6. The ray tracing channel modeling method for ultra-large-scale MIMO communication according to claim 1, characterized in that: The selected antenna elements are simulated by ray tracing according to the reflection and diffraction propagation mechanism. The specific process of determining the ray path is as follows: i. Take the position of each selected antenna unit in the simulation scene as the transmitting end, emit rays to the surrounding area, and record the reflection order and diffraction order of the rays as zero; ii. For each ray, when it hits a reflective surface, a reflected ray is generated according to the mirror reflection principle, and the reflection order is increased by one; when it hits a splitter, a diffracted ray is generated according to the consistent diffraction principle, and the diffraction order is increased by one; iii. Repeat step ii for the reflected ray and the diffracted ray until the reflection order is equal to the set upper limit of the reflection order or the diffraction order is equal to the set upper limit of the diffraction order, stop propagating the ray, and record the propagation trajectory of the ray; iv. Select the propagation trajectory that can reach the receiving end position from the propagation trajectory of all rays as the ray path.

7. The ray tracing channel modeling method for ultra-large-scale MIMO communication according to claim 6, characterized in that: The process of screening out non-repeated ray paths is as follows: for all ray paths, determine whether the order of objects touched during the propagation of the ray paths is exactly the same. If they are the same, delete any ray path; Otherwise, both ray paths are retained.

8. The ray tracing channel modeling method for ultra-large-scale MIMO communication according to claim 1, characterized in that: Step S6 includes the following sub-steps: Step S6.1: Calculate the time delay and angle information of each ray path based on all ray paths of each antenna element in the MIMO antenna array; Step S6.2: Calculate the electric field at the receiving end of the simulation scenario based on all ray paths of each antenna element in the MIMO antenna array to determine the received power of the antenna element; Step S6.3: Use the time delay, angle information, and received power corresponding to all antenna units in the MIMO antenna array as the channel characteristics of the ultra-large-scale MIMO communication scenario to realize the construction of a ray tracing channel model for ultra-large-scale MIMO communication.

9. The ray tracing channel modeling method for ultra-large-scale MIMO communication according to claim 1, characterized in that: The electric field of the antenna unit at the receiving end of the simulation scene is obtained by summing the electric fields of all ray paths of the antenna unit at the receiving end of the simulation scene, wherein the calculation process of the electric field of each ray path at the receiving end of the simulation scene is: in, is the electric field of a certain ray path in the antenna unit at the receiving end of the simulation scene, is the electric field of the emitted ray corresponding to the ray path, is the total number of reflections, is the ray number in the ray path The reflection coefficient matrix of the secondary reflection, is the wave number, is the propagation distance of the ray path, Is an imaginary unit.

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