Selection device, selection method, and program

Abstract

According to the present invention, a selection device for selecting a simulation method for a wireless communication system comprises: an input unit for inputting simulation request information; and a selection unit for calculating an evaluation index for each of a plurality of simulation methods and selecting a simulation method having the largest evaluation index from among the plurality of simulation methods.

Description

Selection device, selection method, and program

[0001] The present invention relates to techniques for performing computer simulations on wireless communication systems.

[0002] In recent years, various wireless communication standards have been developed, and wireless technologies that can keep up with ever-changing user demands and radio wave conditions to provide a natural communication environment that does not require users to be aware of the wireless network are also being studied (e.g., Non-Patent Document 1).

[0003] In wireless technologies in general, including the wireless technologies described above, a technique for predicting the communication quality of a wireless communication system by simulation is an important technique.

[0004] Motoharu Sasaki, Toshiro Nakahira, Takatsune Moriyama, Tomoaki Ogawa, Yusuke Asai, and Yasushi Takatori, "Multi-radio Proactive Control Technology (Cradio(r)): A Natural Communication Environment where Users Do Not Need to Be Aware of the Wireless Network" NTT Technical Review, Vol. 19, No. 8, Aug. 2021. https: / / www.ntt-review.jp / archive / ntttechnical.php?contents=ntr202108ra1.pdf&mode=show_pdf

[0005] In a simulation of a wireless communication system, for example, the wireless communication quality of each terminal when a base station is placed at a certain location is predicted.

[0006] However, when there are many candidates for placement of devices in a wireless communication system (for example, relay nodes such as a Reconfigurable Intelligent Surface (RIS) or a relay station), it is difficult to select an appropriate simulation method. If an appropriate simulation method is not selected, it may not be possible to obtain results with the desired accuracy and calculation time.

[0007] The present invention has been made in view of the above points, and an object of the present invention is to provide a technique that enables an appropriate selection of a simulation method in a wireless communication system.

[0008] According to the disclosed technology, there is provided a selection device for selecting a simulation method for a wireless communication system, comprising: an input unit for inputting simulation request information; and a selection unit for calculating an evaluation index for each of a plurality of simulation methods and selecting, from the plurality of simulation methods, the simulation method that maximizes the evaluation index.

[0009] The disclosed technology provides a technology that enables an appropriate selection of a simulation method in a wireless communication system.

[0010] It is a diagram showing an example of the configuration of a wireless communication system to be a target of a simulation. It is a diagram showing the configuration of a selection device 100. It is a diagram showing the configuration of the selection device 100. It is a flowchart for explaining the operation of the selection device 100. It is a diagram showing an example of the hardware configuration of the selection device 100.

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The embodiment described below is merely an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0012] A technique for appropriately selecting a simulation method in a wireless communication system will be described in detail below.

[0013] (System Configuration Example) An example of the overall configuration of a wireless communication system according to this embodiment is shown in Fig. 1. This wireless communication system is an example of a wireless communication system that is the subject of a simulation.

[0014] 1, the wireless communication system includes a plurality of wireless nodes 10 and a plurality of terminals 20 that communicate wirelessly with the wireless nodes 10. The wireless nodes 10 are, for example, base stations, RISs (Reconfigurable Intelligent Surfaces), etc. The terminals 20 are, for example, general terminals such as smartphones.

[0015] The wireless node 10 is assumed to be movable, but some wireless nodes 10 may be immobile. Furthermore, parameters of the wireless node 10, such as the antenna direction, reflector direction, beam direction, and transmission power, can be changed arbitrarily.

[0016] The wireless communication system in this embodiment is not limited to a specific wireless method, but may be, for example, 5G, wireless LAN, or the like.

[0017] Furthermore, from the viewpoint of simulation, this wireless communication system also includes obstacles to the propagation of radio waves, such as buildings, people, etc. By simulating the wireless communication system, it is possible to estimate the received radio wave strength or throughput in a certain area, for example, when a base station as a wireless node is installed in a certain location and the reflector of the RIS is set at a certain angle.

[0018] In this embodiment, for example, it is assumed that in this wireless communication system, a simulation is performed to evaluate the communication quality (e.g., throughput) of each terminal when using radio waves of a certain frequency while appropriately changing changeable parameters.

[0019] (Device Configuration Example) In this embodiment, the selection device 100 selects a simulation method according to the procedure described below.

[0020] Fig. 2 shows an example of the configuration of the selection device 100. As shown in Fig. 2, the selection device 100 has an input unit 110, a selection unit 120, an output unit 130, and a data storage unit 140. The operation of each unit will be explained in the processing procedure section.

[0021] The configuration shown in FIG. 2 is a configuration that assumes that the selection device 100 selects a simulation method, and that the actual simulation is performed by another device.

[0022] The selection device 100 may execute the simulation and also perform subsequent control. The device configuration in this case is shown in FIG. 3. As shown in FIG. 3, in this configuration example, the selection device 100 has an input unit 110, a selection unit 120, a simulation execution unit 150, a control unit 160, and a data storage unit 140. The operation of each unit will be explained in the processing procedure section. In the following explanation, the operation of the selection device 100 will be explained using the configuration shown in FIG. 3 as an example.

[0023] (Example of Operation of Selection Device 100) An example of operation of the selection device 100 will be described in accordance with the procedure of the flowchart shown in FIG.

[0024] <S101 (Step 101)> In S101, a user inputs simulation request information from the input unit 110. The simulation request information is stored in the data storage unit 140 by the input unit 110. A calculation method for an evaluation index, which will be described later, is selected based on the simulation request information.

[0025] The simulation request information may be, for example, one or more or all of the following: the purpose of the simulation, the accuracy required for the simulation, and the calculation time allowed for the simulation (allowable calculation time). The simulation request information may also be information other than these.

[0026] Assuming that the simulation request information is an "application," examples of the application include (1) to (4) below. For each of (1) to (4), examples of simulation requirements (characteristics) are also shown.

[0027] (1) Pre-operational channel placement design evaluation In pre-operational channel placement design evaluation, the calculation speed of the simulation may be slow, but high accuracy (e.g., accuracy of estimating quality, etc.) is desirable.

[0028] (2) Redesign during operation or initial control in control In redesign or initial control during operation, it is desirable that the calculation speed of the simulation is relatively fast, but the accuracy may be low.

[0029] (3) Proactive Control During Operation For proactive control during operation, it is desirable that the calculation speed of the simulation is fast and the accuracy is medium.

[0030] (4) Minor Modifications During Operation When making minor modifications during operation, the calculation speed of the simulation may be slow, but high accuracy is preferable.

[0031] The input unit 110 may automatically detect (or generate) the simulation request information from information that can detect (estimate) the simulation request information (for example, environment grasping data, quality grasping data, etc.).

[0032] <S102> In S102, the selection unit 120 selects, from among a plurality of simulation methods, a simulation method that maximizes the evaluation index, based on the simulation request information obtained in S101.

[0033] In this embodiment, the "simulation method" includes a propagation estimation method and a simulation level. However, this is an example, and the simulation method may include things other than the "propagation estimation method and simulation level." Also, the propagation estimation method may be determined in advance, and the simulation level may be selected as the simulation method.

[0034] Below, examples of (1) options for propagation estimation methods, (2) options for simulation levels, (3) methods for determining evaluation indices, and (4) methods for selecting simulation methods will be described in detail.

[0035] (1) Options for Propagation Estimation Method Examples of options for the propagation estimation method are as follows: Note that the options below are only examples, and propagation estimation methods other than the options shown below may also be included as options.

[0036] Options: LoS / NLoS attenuation formula, ray tracing (consider only straight propagation path loss, one reflection, one diffraction), ray tracing (consider only straight propagation path loss, two reflections, one diffraction), ray tracing (consider Fresnel zone), ray tracing (consider delay and angular spread), prediction by machine learning, prediction using a probabilistic model, with / without correction by sensing (2) Options for simulation level Examples of options for the simulation level are as follows: Note that the options below are just examples, and simulation levels other than those shown in the options below may also be included as options.

[0037] Options: Link level (no consideration of geometry), link level (consideration of geometry), system level (function focus), system level (complete) Note that link level simulation models the functions of the transmitter and receiver, as well as the physical behavior of the radio propagation path between them, and is applied to testing a series of functions and performance from transmission to reception.

[0038] System-level simulation is an evaluation method that incorporates terminal selection and quality control based on the radio wave propagation environment in an environment where multiple wireless nodes (base stations, etc.) and terminals exist. Geometry is an index that shows the quality of an area using received power distribution, etc.

[0039] (3) Method for Determining Evaluation Index The selection unit 120 calculates the evaluation index as, for example, "evaluation index = A × accuracy + B × calculation time." For example, each parameter (specifically, coefficients A and B) is stored in the data storage unit 140 in association with simulation request information.

[0040] For example, parameters are stored in the data storage unit 140 in the form of "Use 1: A=A1, B=B1" and "Use 2: A=A2, B=B2."

[0041] The selection unit 120 determines the evaluation index by acquiring, from the data storage unit 140, parameters corresponding to the simulation request information acquired in S101.

[0042] (4) Method for Selecting Simulation Method The selection unit 120 calculates an evaluation index for each simulation method that is a combination of a propagation estimation method in the propagation estimation method options and a simulation level in the simulation level options, and selects the simulation method that maximizes the evaluation index.

[0043] Here, it is assumed that the evaluation index is "Evaluation index = A x accuracy + B x calculation time." In this case, the coefficients A and B are determined by the method described above.

[0044] The "calculation time" can be calculated, for example, by multiplying the standard time in the simulation method by the number of trials (the number of candidate position directions, etc.). For example, when performing a "link level (no consideration of geometry)" simulation using "ray tracing (considering only straight-line propagation path loss, one reflection, one diffraction)," if the standard time in the simulation method is 10 and the number of trials is 10, the calculation time is 10 x 10 = 100.

[0045] As for "accuracy," for example, it is assumed that an accuracy (e.g., x%) is determined in advance for each simulation method formed by a combination of a propagation estimation method in the propagation estimation method options and a simulation level in the simulation level options, and that this value is stored in the data storage unit 140. The selection unit 120 reads out, from the data storage unit 140, the accuracy corresponding to the simulation method to be evaluated.

[0046] For example, assume that this accuracy is 90. If calculation time=100, A=0.5, and B=0.5, then the evaluation index=0.5×90+0.5×100=95.

[0047] Here, it is assumed that simulation method A is selected as the simulation method.

[0048] 2 is used, the selection device 100 outputs the determined simulation method A from the output unit 130. When the selection device 100 shown in FIG. 3 is used, the process proceeds to the next step S103.

[0049] <S103> In S103, the simulation execution unit 150 executes a simulation using the simulation method A determined in S102. After the simulation is executed, the simulation results may be output to the outside.

[0050] <S104> In S104, the control unit 160 controls the wireless communication system based on the simulation results obtained in S103. For example, if the simulation performed in S103 shows that a desired wireless communication quality is obtained when the antenna direction of a certain base station is changed from the current direction to another direction, the control unit 160 executes control to change the antenna direction of the base station from the current direction to another direction.

[0051] (Hardware Configuration Example) The selection device 100 described in this embodiment can be realized, for example, by causing a computer to execute a program. This computer may be a physical computer or a virtual machine on the cloud.

[0052] That is, the selecting device 100 can be realized by using hardware resources such as a CPU and memory built into a computer to execute a program corresponding to the processing performed by the selecting device 100. The program can be recorded on a computer-readable recording medium (such as a portable memory) and can be saved or distributed. The program can also be provided via a network such as the Internet or email.

[0053] Fig. 5 is a diagram showing an example of the hardware configuration of the computer. The computer in Fig. 5 includes a drive device 1000, an auxiliary storage device 1002, a memory device 1003, a CPU 1004, an interface device 1005, a display device 1006, an input device 1007, an output device 1008, and the like, all of which are interconnected via a bus B. The computer may further include a GPU.

[0054] The program that realizes the processing on the computer is provided by a recording medium 1001, such as a CD-ROM or a memory card. When the recording medium 1001 storing the program is set in the drive device 1000, the program is installed from the recording medium 1001 to the auxiliary storage device 1002 via the drive device 1000. However, the program does not necessarily have to be installed from the recording medium 1001, but may be downloaded from another computer via a network. The auxiliary storage device 1002 stores the installed program as well as necessary files, data, etc.

[0055] The memory device 1003 reads and stores the program from the auxiliary storage device 1002 when an instruction to start the program is received. The CPU 1004 realizes functions related to the selection device 100 in accordance with the program stored in the memory device 1003. The interface device 1005 is used as an interface for connecting to a network, etc. The display device 1006 displays a GUI (Graphical User Interface) or the like according to the program. The input device 1007 is composed of a keyboard, mouse, buttons, a touch panel, etc., and is used to input various operation instructions. The output device 1008 outputs the results of calculations.

[0056] (Summary, Effects, etc. of the Embodiment) As described above, in the present embodiment, the selection device 100 uses the required accuracy and processing time as evaluation indices and selects a wireless communication simulation method that maximizes these. The selection device 100 can control the wireless system and perform other technical studies based on the results of the selected wireless communication simulation.

[0057] The above technology makes it possible to perform wireless communication simulations while satisfying the required application, estimation accuracy, and calculation time as much as possible, especially under conditions where calculation time is limited. When using this technology to design and control wireless systems, processing can be performed with accuracy and processing time suited to the application.

[0058] The following additional notes are provided regarding the above-described embodiments.

[0059] <Additional Notes> (Additional Item 1) A selection device for selecting a simulation method for a wireless communication system, comprising: a memory; and at least one processor connected to the memory, wherein the processor inputs simulation request information, calculates an evaluation index for each of a plurality of simulation methods, and selects from the plurality of simulation methods a simulation method that maximizes the evaluation index. (Additional Item 2) The selection device according to Additional Item 1, wherein the memory stores parameters used to calculate the evaluation index in association with the simulation request information, and the processor reads from the memory parameters corresponding to the simulation request information input by the input unit and calculates the evaluation index using the parameters. (Additional Item 3) The selection device according to Additional Item 1 or 2, wherein the simulation request information includes at least one of an application of the simulation, a required accuracy for the simulation, and an allowable calculation time for the simulation. (Additional Item 4) The selection device according to any one of Additional Items 1 to 3, wherein the simulation method includes a propagation estimation method and a simulation method. (Supplementary Item 5) The selection device according to any one of Supplementary Items 1 to 4, wherein the processor calculates the evaluation index using simulation accuracy and calculation time required for the simulation. (Supplementary Item 6) A selection method executed by a selection device for selecting a simulation method for a wireless communication system, comprising: an input step of inputting simulation request information; and a selection step of calculating an evaluation index for each of a plurality of simulation methods and selecting, from the plurality of simulation methods, the simulation method that maximizes the evaluation index. (Supplementary Item 7) A non-transitory storage medium storing a program for causing a computer to function as each unit in the selection device according to any one of Supplementary Items 1 to 5.

[0060] Although the present embodiment has been described above, the present invention is not limited to such a specific embodiment, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims.

[0061] 10 Wireless node 20 Terminal 100 Selection device 110 Input unit 120 Selection unit 130 Output unit 140 Data storage unit 150 Simulation execution unit 160 Control unit 1000 Drive device 1001 Recording medium 1002 Auxiliary storage device 1003 Memory device 1004 CPU 1005 Interface device 1006 Display device 1007 Input device 1008 Output device

Claims

1. A selection device for selecting a simulation method for a wireless communication system, comprising: - an input unit for inputting simulation requirement information; - a selection unit for calculating evaluation indexes for each of a plurality of simulation methods and selecting, from among the plurality of simulation methods, a simulation method for which the evaluation index is maximized.

2. The selection device according to claim 1, further comprising a data storage unit for storing, in association with the simulation requirement information, parameters used for calculating the evaluation indexes, wherein the selection unit reads, from the data storage unit, parameters corresponding to the simulation requirement information input by the input unit and calculates the evaluation indexes using the parameters.

3. The selection device according to claim 1, wherein the simulation requirement information includes at least one of a use of the simulation, an accuracy required for the simulation, and a calculation time allowable for the simulation.

4. The selection device according to claim 1, wherein the simulation method includes a propagation estimation method and a simulation method.

5. The selection device according to claim 1, wherein the selection unit calculates the evaluation index using an accuracy of the simulation and a calculation time required for the simulation.

6. A selection method executed by a selection device for selecting a simulation method for a wireless communication system, comprising: - an input step of inputting simulation requirement information; - a selection step of calculating evaluation indexes for each of a plurality of simulation methods and selecting, from among the plurality of simulation methods, a simulation method for which the evaluation index is maximized.

7. A program for causing a computer to function as each unit in the selection device according to any one of claims 1 to 5.

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