Communication quality estimation device, communication quality estimation method, and communication quality estimation program

Abstract

To provide a technique that enables the estimation of future communication quality from actually measured past communication quality information without covering communication conditions that affect communication traffic, in estimating the communication quality of general-purpose wireless communication systems.SOLUTION: A communication quality estimation device of the present invention includes: a communication traffic acquisition unit that predicts an amount of communication traffic based on human flow data under predetermined communication conditions; a communication information receiving unit that generates a communication quality estimation model from a first amount of communication traffic and communication quality information associated with the first amount of traffic; and a communication quality estimation unit that estimates communication quality under estimation conditions from the communication quality estimation model and a second amount of communication traffic predicted under the estimation conditions in the communication traffic acquisition unit. The communication quality estimation device estimates the communication quality of wireless communication used for mobile vehicles for passenger transportation.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a communication quality estimation device, a communication quality estimation method, and a communication quality estimation program for estimating the communication quality of wireless communication used mainly for moving bodies involved in passenger transportation. [Background technology]

[0002] In recent years, with the spread of networks, applications (hereafter simply referred to as "apps") and services are being provided via networks. To access these apps and services, there are many systems that use general-purpose wireless communication systems such as LTE (Long Term Evolution) and 5G (5th Generation). One example that is currently attracting attention is the use of networked systems in railway systems, which aim to provide safe, accurate, and comfortable train operation.

[0003] In current railway systems, in order to ensure safe, accurate, and comfortable train operation, dedicated wireless systems are used, or siloed wireless systems are built to meet the different communication requirements of multiple railway apps. As a result, current railway systems face challenges such as high implementation and operating costs, and difficulty in linking different railway apps. In response to these challenges, building a railway system that utilizes a general-purpose wireless communication system is expected to reduce fixed costs by achieving asset-less, zero-infrastructure operation.

[0004] However, using a general-purpose wireless communication system presents challenges, such as the need to share the network with general users and the lack of wireless coverage specifically for railways, making it impossible to guarantee that the communication requirements of railway apps will be met across the entire railway line. Therefore, the design of railway systems that take into account the communication quality on the lines that use the railway system and the introduction of a communication platform with communication control functions that guarantee communication quality for each railway app are being considered. A communication platform can guarantee the communication quality of railway apps even in areas with insufficient communication quality by implementing communication control such as utilizing multiple communication paths, transmitting redundant packets, and adaptively switching communication paths. Therefore, by utilizing a communication platform, it is possible to realize a railway system that aims for safe, accurate, and comfortable train operation even in areas with insufficient communication quality.

[0005] As described above, system design for providing appropriate applications and services is essential for realizing a system that utilizes a general-purpose wireless communication system, and estimation of communication quality is essential for realizing communication control using a communication platform. Patent Document 1 describes, as a technology relating to a method for estimating communication quality, a communication quality estimation device having an estimation equation generation unit that generates an estimation equation for communication quality using regression analysis from data obtained in advance on the relationship between the number of wireless interfaces of a terminal observed per unit time and communication quality, an input unit that accepts an input of the number of wireless interfaces observed per unit time in an estimation target area, a communication quality estimation value calculation unit that calculates a communication quality estimation value using the generated estimation equation from the accepted number of wireless interfaces, and an output unit that outputs the calculated communication quality estimation value. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2018-19368 Summary of the Invention [Problem to be solved by the invention]

[0007] In a general-purpose wireless communication system, since the system is a shared network with general users, the size of the wireless resources allocated to the wireless terminals that are the subject of estimation changes depending on the communication traffic volume and the number of wireless terminals that are not the subject of estimation and that exist within the communication area. Also, the communication quality when using the general-purpose wireless communication system changes depending on the size of the wireless resources allocated to the wireless terminals that are the subject of estimation.

[0008] Therefore, in order to estimate future communication quality, it is necessary to take into account communication conditions such as date and time, location, weather, etc., which may change the communication traffic of wireless terminals that are not subject to estimation. In other words, to realize a technology that estimates communication quality using actually measured past communication quality information, it is necessary to cover all of the above communication conditions, which poses challenges such as the high man-hours and cost required to actually measure communication quality and accumulate data, and the enormous amount of data to be accumulated.

[0009] In existing methods such as that disclosed in Patent Document 1, the relationship between the number of terminal wireless interfaces observed per unit time and communication quality is obtained by regression analysis, and the communication quality is estimated using the obtained estimation formula. However, in order to perform regression analysis, a sufficient amount of past communication quality information must be accumulated, and the accumulated past communication quality information must also cover communication conditions where communication traffic from wireless terminals not subject to estimation changes. Therefore, this method does not solve the problems mentioned above, such as the labor and cost required to acquire future communication quality and the enormous amount of data to be accumulated.

[0010] Therefore, the present invention has been made in consideration of the above points, and aims to provide a technology that enables estimation of future communication quality of a general-purpose wireless communication system from actually measured past communication quality information, without covering all communication conditions that affect communication traffic. [Means for solving the problem]

[0011] In order to solve the above problems, a communication quality estimation device according to one embodiment of the present invention includes a communication traffic acquisition unit that predicts communication traffic volume based on people flow data under specified communication conditions, a communication information receiving unit that generates a communication quality estimation model from a first communication traffic volume and communication quality information linked to the first traffic volume, and a communication quality estimation unit that estimates communication quality under the estimation conditions from the communication quality estimation model and a second communication traffic volume predicted under the estimation conditions by the communication traffic acquisition unit, and estimates the communication quality of wireless communication used for mobile bodies involved in passenger transport. [Effects of the Invention]

[0012] According to the present invention, it is possible to estimate future communication quality for the communication conditions to be estimated from communication traffic volume based on people flow data, and there is no need to prepare past communication quality information that covers all communication conditions, so communication quality can be estimated with little effort, low cost, and a small amount of data. Problems, configurations, and effects other than those described above will become apparent from the description of the following embodiments. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a block diagram illustrating an example of a physical configuration of a communication quality estimation device according to a first embodiment. [Figure 2] 1 is a block diagram showing an example of a configuration of a communication quality estimation device according to an embodiment of the present invention. [Figure 3] FIG. 4 is a diagram showing an example of an output screen from the measurement condition determining device displayed via an output interface in the first embodiment. [Figure 4] FIG. 10 is a diagram showing an example of an output screen from the data estimating device displayed via an output interface in the first to third embodiments. [Figure 5] 1 is a block diagram showing an example of the configuration of a measurement condition determination device included in a communication quality estimation device according to a first embodiment; [Figure 6]1 is a block diagram illustrating an example of the configuration of a data estimation device included in a communication quality estimation device according to a first embodiment. [Figure 7] 1 is a flowchart illustrating an overall processing procedure of a communication traffic acquisition unit included in a measurement condition determination device and a data estimation device according to a first embodiment. [Figure 8] 1 is a flowchart showing the overall processing procedure of a measurement time period acquisition unit included in the measurement condition determination device of the first embodiment. [Figure 9] 3 is a flowchart illustrating an overall processing procedure of a communication information receiving unit included in the data estimation device according to the first embodiment. FIG. [Figure 10] 3 is a flowchart illustrating an overall processing procedure of a communication quality estimation unit included in the data estimation device according to the first embodiment. FIG. [Figure 11] FIG. 10 is a block diagram showing an example of the configuration of a measurement condition determination device included in a communication quality estimation device according to a second embodiment. [Figure 12] FIG. 10 is a flowchart showing the overall processing procedure of a measurement position acquisition unit included in the measurement condition determination device of the second embodiment. [Figure 13] FIG. 11 is a block diagram showing an example of the physical configuration of the entire railway system in which a communication platform to which the present invention is applied in a third embodiment is introduced. [Figure 14] FIG. 11 is a block diagram showing an example of the configuration of a communication quality estimation device included in a communication control determination device of a third embodiment. [Figure 15] FIG. 11 is a diagram illustrating an example of a data configuration of information stored in a past communication information database according to a third embodiment. [Figure 16] FIG. 11 is a flowchart illustrating an overall processing procedure of a communication information receiving unit included in a communication quality estimation device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, with reference to the drawings, a description will be given of Examples 1 to 3 as modes for carrying out the present invention. Note that the present invention is not limited to these Examples. In addition, in the description of the drawings, the same parts are denoted by the same reference numerals.

[0015] [Example 1] 1 is a block diagram illustrating an example of a physical configuration of a communication quality estimation device according to a first embodiment. This communication quality estimation device makes it possible to obtain information for determining whether or not to introduce a railway system utilizing a general-purpose wireless communication system, and to estimate communication quality and perform communication control after the introduction. Note that in the present invention, the general-purpose wireless communication system is not limited to LTE or 5G, as long as it is a wireless communication system that is a network shared with general users. The communication quality estimation device 101 includes a measurement condition determination device 102 and a data estimation device 103 .

[0016] The measurement condition determination device 102 is a device that determines communication conditions under which communication quality information required for estimating communication quality in the data estimation device 103 is measured by the data acquisition device 104. Here, the communication conditions are conditions under which communication traffic changes when communication is performed in a predetermined wireless system, such as date and time, location, and weather.

[0017] The data estimation device 103 is a device that estimates future communication quality from past communication quality information measured by the data acquisition device 104 under the communication conditions determined by the measurement condition determination device 102. The present invention particularly relates to a device that estimates future communication quality as the data estimation device 103, and the communication quality information is information that indicates the quality of communication, the characteristics of which vary due to changes in communication conditions, such as throughput, available bandwidth, communication delay time, and packet error rate.

[0018] The data acquisition device 104 is a device that acquires communication quality under the communication conditions determined by the measurement condition determination device 102. Here, methods for acquiring communication quality include, for example, methods using active measurement and passive measurement, and any method may be used in the present invention.

[0019] FIG. 2 is a block diagram showing an example of the configuration of a communication quality estimation device according to an embodiment of the present invention. The communication quality estimation device 101 is configured by a computer having a processor (CPU (Central Processing Unit)) 201, a memory 202, an auxiliary storage device 204, a communication interface 205, an input interface 203, and an output interface 206. In Fig. 2, "interface" is abbreviated as "I / F."

[0020] The processor (CPU) 201 is an arithmetic device that executes programs stored in the memory 202, and executes various programs to realize the processing of the communication quality estimation device 101. Note that part of the processing performed by the processor (CPU) 201 by executing the programs may be executed by another arithmetic device (for example, hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array)).

[0021] The memory 202 includes a non-volatile storage element, Read Only Memory (ROM), and a volatile storage element, Random Access Memory (RAM). The ROM stores unchanging programs (e.g., a Basic Input Output System (BIOS)). The RAM is a high-speed, volatile storage element, such as a Dynamic Random Access Memory (DRAM), and temporarily stores programs executed by the processor 201 and data used when the programs are executed.

[0022] The auxiliary storage device 204 is a large-capacity, non-volatile storage device such as a magnetic storage device (HDD (Hard Disk Drive)) or a flash memory (SSD (Solid State Drive)), and stores data used by the processor 201 when executing a program and the program executed by the processor 201. That is, the program is read from the auxiliary storage device 204, loaded into the memory 202, and executed by the processor 201 to realize each function of the communication quality estimation device 101.

[0023] The communication interface 205 is a network interface device that controls communication with other devices according to a predetermined protocol.

[0024] The input interface 203 is an interface to which an input device 207 such as a keyboard or a mouse is connected and which receives input from an operator.

[0025] The output interface 206 is connected to an output device 208 such as a display device, and is an interface for outputting the results of program execution in a format that can be viewed by an operator.

[0026] The program executed by the processor 201 is provided to the communication quality estimation device 101 via removable media (such as a CD (Compact Disk)-ROM or flash memory) and stored in a non-volatile auxiliary storage device 204, which is a non-transitory storage medium. For this reason, the communication quality estimation device 101 preferably has an interface for reading data from removable media.

[0027] FIG. 3 is a diagram showing an example of an output screen 301 from the measurement condition determining device 102 displayed via the output interface 206 in the first embodiment. As an output screen 301, a setting list 302 for inputting and setting measurement conditions into the measurement condition determination device 102 and a result list 312 which is the output results based on the input settings are output on a graphical interface.

[0028] First, measurement conditions are input and set in each item of the setting list 302. Measurement conditions are communication conditions that generate communication traffic for wireless communication that is the target of measuring communication quality information. In Fig. 3, the setting list 302 displays condition items related to a measurable period 303, a measurement target location 304, weather 305, a wireless system 306, a wireless terminal 307, people flow data 308 used to acquire communication traffic volume, communication traffic parameters 309, and a measurement availability setting 310 for an estimation target location. However, the condition items are not limited to the example in Fig. 3. Condition items that can be measurement conditions and input items to be selected from them are collected in communication condition information 503, which will be described later, and are designed to be displayed and input from there as needed. Possible input items include wireless system 306, the type of system used for wireless communication such as 3G, LTE, or 5G; wireless terminal, for example, the type of router installed on board the vehicle for communication with the ground; people flow data 308, the type of people flow such as occupancy rate, population, and number of event attendees; and communication traffic parameters 309, for example, the type of combination (preset) of setting values ​​for communication traffic parameters for children, adults, and elderly generations. Estimation target location measurement feasibility setting 310 is set by checking No if measurement at the estimation target location is not possible for some reason, and Yes if measurement is possible.

[0029] Next, the process is executed by pressing the measurement condition acquisition start button 311. As a result, a graph showing the predicted communication traffic volume characteristics (communication traffic volume characteristics for measurement) for the time periods included in the measurement period, and a list of measurement conditions (date and time and weather) and the corresponding predicted communication traffic volumes are displayed as a measurement condition list in the result list 312. The granularity of the time periods is not particularly limited, and may be every hour, for example.

[0030] Thereafter, as will be described later, the measurement time period for actual measurement is determined from the measurement condition list, and communication quality information during the measurement time period is measured at the measurement target location by the data acquisition device 104. Then, the communication quality is estimated by the data estimation device 103 from the measured communication quality information.

[0031] When inputting and setting measurement conditions before measurement, one possible method is to input multiple possible conditions (for example, for weather 305, sunny, rainy, cloudy, etc.) to create a measurement condition list, and then associate the measurement condition (sunny) that matches the weather at the time of measurement (for example, sunny) with the actual measurement value of communication quality for the predicted traffic volume.When inputting and setting measurement conditions during measurement, it is sufficient to input the measurement condition (for example, sunny) that corresponds to the environment at the time of measurement.

[0032] FIG. 4 is a diagram showing an output screen 401 from the data estimating device 103 displayed via the output interface 206 in the first embodiment. As an output screen 401, a setting list 402 for inputting and setting estimation conditions to the data estimation device 103 and a result list 411 which is the output results based on the input settings are output on a graphical interface.

[0033] First, estimation conditions are input and set in each item of the setting list 402. The estimation conditions are the communication conditions under which the communication traffic of the wireless communication to be estimated occurs. In FIG. 4, the setting list 402 displays items related to a reference destination 403 storing past measured communication quality information 601 used for estimation, an estimation target period 404, weather 405, people flow data 406 used to acquire communication traffic volume, communication traffic parameters 407, a relationship 408 between the estimation target location and the measurement location, and an estimation target location 409. However, the condition items are not limited to the example in FIG. 4. The condition items that can become estimation conditions and the input items to be selected therefrom are collected in communication condition information 503 (described later) and are designed to be displayed and input as needed. The contents of the condition items and input items are the same as those in the setting list 302 of the measurement condition determination device 102 in FIG. 3, so a description thereof will be omitted.

[0034] Next, processing is executed by pressing the communication quality estimation start button 410. This displays a graph showing the communication quality characteristics (communication quality estimation model) for the communication traffic volume used to measure the communication quality information (hereinafter also referred to as the first communication traffic volume), the characteristics (communication traffic volume characteristics for estimation) for the time period included in the estimation target period of the communication traffic volume predicted under the estimation conditions (hereinafter also referred to as the second communication traffic volume), and the communication quality characteristics estimated for that time period (estimated communication quality characteristics). As a result, based on the displayed estimated communication quality characteristics, a system design for providing appropriate applications and services and appropriate communication control in the communication control device 1308 (described later) by the communication platform 1302 are realized.

[0035] FIG. 5 is a block diagram showing an example of the configuration of the measurement condition determination device 102 included in the communication quality estimation device 101 according to the first embodiment. The measurement condition determining device 102 includes a communication traffic acquiring unit 504 and a measurement time period acquiring unit 505 . The communication traffic acquisition unit 504 receives people flow information 501, train operation information 502, and communication condition information 503 as input, and outputs information relating to the predicted communication traffic volume in the measurement period. The measurement time period acquisition unit 505 outputs the measurement time period to be measured by the data acquisition device 104 based on the measurement conditions and information on the predicted communication traffic volume during the measurement period. Here, we will explain the people flow information 501, train operation information 502, communication condition information 503, and communication traffic volume. These pieces of information can be stored in the memory 202 or the auxiliary storage device 204 in FIG.

[0036] People flow information 501 is information that collects the number and characteristics of people associated with a date, time, and location (e.g., communication traffic characteristics by generation). Here, location refers to the target area to be measured or estimated. The granularity of the date, time, and location is not particularly limited. For example, the date and time may be hourly, and the location may be latitude and longitude information, a communication area, a station name, or a line name. Furthermore, the source of the data on the granularity of the date, time, location, number of people, and person characteristics is not particularly limited. For example, it may be obtained using a global positioning system (GPS) device, reading physical locations on the rails from a sensor, using train schedule information (train operation information 502), or information on the number of passengers and occupancy rates from a system that manages train operations. The people flow data obtained from the people flow information 501 includes data on the number of people present at a target location by time period and data on the number of passengers on passenger services. These data may also be estimates.

[0037] The train operation information 502 is collected information related to train operations, such as geographical information on railway lines and train schedule information. The source of the train operation information 502 is not particularly limited. For example, it may be a system that manages railway operations.

[0038] The communication condition information 503 is information that collects condition items (date and time, location, weather, etc.) and input items (2022 / 4 / 1, Station A, sunny, etc.) displayed in the setting list 302 of the measurement condition determination device 102 or the setting list 402 of the data estimation device 103, such as the date and time, location, and weather of the measurement target or estimation target. Note that the communication condition information 503 may also include information on factors that change communication traffic of wireless terminals not targeted for estimation, and may include, for example, information to be input regarding the presence or absence of events or communication failures that have occurred around the location targeted for estimation. Data linked to the condition items and input items in the communication condition information 503 can be acquired from the people flow information 501 and the train operation information 502.

[0039] The predicted communication traffic volume is a prediction of the total communication traffic volume occupied by all users who share the communication band of a specified wireless system (e.g., LTE). For example, if there are five users with terminals in a communication area, each communicating at 1 Mbps (bit per second), the communication traffic volume will be 5 Mbps. "User" refers to an individual who affects communication traffic by communicating in a specified communication area, and may include not only a person but also devices such as wireless terminals.

[0040] FIG. 6 is a block diagram showing an example of the configuration of the data estimation device 103 included in the communication quality estimation device 101 according to the first embodiment. The data estimation device 103 includes a communication information receiving unit 602 , a communication traffic acquiring unit 504 , and a communication quality estimating unit 603 .

[0041] The communication information receiving unit 602 receives past measured communication quality information 601 linked to communication traffic volume as input, and outputs a communication quality estimation model for the communication traffic volume. The communication quality estimation unit 603 receives as input a communication quality estimation model for communication traffic volume and communication traffic volume under communication conditions to be estimated, and outputs an estimated communication quality under communication conditions to be estimated.

[0042] Here, the measured communication quality information 601 linked to the first communication traffic volume will be described. The measured communication quality information 601 linked to the first communication traffic volume is communication quality information for the communication traffic volume acquired by the data acquisition device 104. Note that the method for acquiring the first communication traffic volume is not particularly limited. For example, either a method using a predicted communication traffic volume acquired by the measurement condition determination device 102 or a method using an actual measurement value of the total volume of communication traffic volume occupied by all users present in the communication area when actually measured by the data acquisition device 104 may be used.

[0043] 7 is a flowchart showing the overall processing procedure of the communication traffic acquisition unit 504 included in the measurement condition determination device 102 and the data estimation device 103 according to the first embodiment. The operation of each processing step will be described below. In the case of the measurement condition determination device 102, start corresponds to activating the measurement condition acquisition start button 311 in Fig. 3, and in the case of the data estimation device 103, it corresponds to activating the communication quality estimation start button 410 in Fig. 4. Note that, depending on the case, in each step, "communication conditions" refers to measurement conditions or estimation conditions, and "target position" refers to the measurement target position or estimation target position.

[0044] Step S701: Train operation information 502, such as geographical information about railway lines and train schedule information, is acquired from a system related to railway operation.

[0045] Step S702: Based on the people flow information 501 and the communication condition information 503, people flow information linked to the communication condition at the target location is acquired from the train operation information 502 acquired in step S701.

[0046] Step S703: Obtain the time characteristics of the number of users under the communication conditions. For example, obtain the time characteristics of the number of people around the target location, the time characteristics of the number of passengers obtained based on the occupancy rate, and the number of users of surrounding facilities, and then sum them up to obtain the time characteristics of the number of users. Note that in addition to the number of people, the number of wireless terminals may also be added. For example, this may include the number of surveillance cameras that utilize a general-purpose wireless communication system installed in the station, or the number of terminals used for railway wireless.

[0047] Step S704: Communication traffic parameters under communication conditions are acquired from the people flow information 501 and train operation information 502. The communication traffic parameters are parameters that determine the weight of communication traffic to be distributed to each user terminal. For example, assume that children (17 years old and under), adults (18 to 64 years old), and elderly people (65 years old and over) are present around the target location, and the communication traffic volume in the general-purpose wireless communication system increases in the order of children, elderly, and adults. If the communication traffic parameters for the children, adults, and elderly generations are α, β, and γ, respectively, in step S704, the following processing is performed: α = 0.1, β = 0.6, and γ = 0.3. The communication traffic parameters are determined arbitrarily based on the traffic characteristics of users present within the communication area, and may be determined using the route classification of the target to be estimated or the type of application used.

[0048] Step S705: The time characteristics of the communication traffic volume under the communication conditions are obtained from the time characteristics of the number of users under the communication conditions obtained in step S703 and the communication traffic parameters under the communication conditions obtained in step S704. Here, a method for obtaining the time characteristics of the communication traffic volume under the communication conditions will be described using the example shown in steps S703 and S704. The communication traffic volume at a certain time t is calculated by α×(time characteristics of the number of children (t))+β×(time characteristics of the number of adults (t))+γ×(time characteristics of the number of elderly people (t))=0.1×(time characteristics of the number of children (t))+0.6×(time characteristics of the number of adults (t))+0.3×(time characteristics of the number of elderly people (t)). By deriving this formula over all measurable time periods, the time characteristics of the communication traffic volume under the communication conditions can be obtained.

[0049] 8 is a flowchart showing the overall processing procedure of the measurement time period acquisition unit 505 included in the measurement condition determination device 102 according to the first embodiment. The operation of each processing step will be described below.

[0050] Step S801: The time characteristics of the communication traffic volume under the measurement conditions acquired by the communication traffic acquisition unit 504 are sampled at an appropriate granularity. The granularity of the sampling time is not particularly limited, and sampling may be performed every hour, for example.

[0051] Step S802: The communication traffic volumes associated with the sampling time are rearranged according to the magnitude of the communication traffic volumes.

[0052] Step S803: Obtain measurement time periods classified to an appropriate granularity, focusing on the communication traffic volume linked to the communication condition information 503. The method of obtaining the measurement time periods is not particularly limited, and for example, measurement time periods that indicate communication traffic volumes above a predetermined value can be considered, but it is also possible to arbitrarily set a time period that is convenient for measurement. The granularity for classifying communication traffic volumes is not particularly limited, and for example, the communication traffic volumes may be classified in increments of 1 Mbps.

[0053] 9 is a flowchart showing the overall processing procedure of the communication information receiving unit 602 included in the data estimation device 103 according to the first embodiment. The operation of each processing step will be described below.

[0054] Step S901: During the measurement time period, the measured communication quality information 601 associated with the communication traffic volume is acquired from the data acquisition device 104.

[0055] Step S902: The communication quality information acquired in step S901 is processed to generate a communication quality estimation model for the communication traffic volume. Processing of the communication quality information includes processing to remove outliers, processing to appropriately round the measured communication quality information according to the position and time granularity, and processing to sort the communication quality information by the size of the communication traffic volume. Examples of processing to remove outliers include cluster analysis and the Smirnoff-Grubbs test, and any of these methods may be used. Furthermore, the communication quality estimation model for the communication traffic volume to be generated may be generated as discrete data, as a mathematical formula, or as a probabilistic model.

[0056] FIG. 10 is a flowchart illustrating the overall processing procedure of the communication quality estimation unit 603 included in the data estimation device 103 according to the first embodiment.

[0057] Step S1001: The communication traffic acquisition unit 504 acquires the communication traffic volume under the communication conditions (estimation conditions) to be estimated.

[0058] Step S1002: A communication quality estimation model for the communication traffic volume based on the actually measured communication quality information generated by the communication information receiving unit 602 is acquired.

[0059] Step S1003: An estimated communication quality under the estimation conditions is obtained from the communication traffic volume under the estimation conditions obtained in steps S1001 and S1002 and a communication quality estimation model for the communication traffic volume based on actually measured communication information. Regarding the method of obtaining the estimated communication quality, for example, the communication traffic volume under the estimation conditions at time t is A(t), and the communication quality estimation model for the communication traffic volume R based on actually measured communication quality information is B(t, R). In this case, the estimated communication quality at time t is B(A(t), R), and by performing a similar calculation over all times to be estimated, an estimated communication quality under the communication conditions to be estimated can be obtained.

[0060] In the first embodiment, a communication quality estimation model for communication traffic volume is generated from the measured communication quality information 601 measured based on the communication traffic volume acquired from the measurement condition determination device 102, and an estimated communication quality is obtained using the communication quality estimation model and the communication traffic volume under the communication conditions to be estimated. As a result, if a communication quality estimation model for the estimation target location can be generated, it is possible to obtain communication quality under comprehensive communication conditions at the estimation target location by utilizing the strong correlation between communication quality and communication traffic volume, without the need for comprehensive measurements under different communication conditions such as date, time, and weather. For example, if the weather in the measurement conditions is set to "sunny" (see 305 in Figure 3) and the communication quality information is measured to generate a communication quality estimation model, estimated communication quality characteristics can be obtained even if the weather in the estimation conditions is set to "rainy" (see 405 in Figure 4). Similarly, if station A is selected as the measurement target location in the measurement conditions and a communication quality estimation model is generated, communication quality can be estimated even if the estimation target location is station B.

[0061] [Example 2] Next, a second embodiment of the present invention will be described. However, the description of the second embodiment will focus on differences from the first embodiment. The second embodiment is similar to the first embodiment unless otherwise specified. Example 2 also assumes the estimation of communication quality for the purpose of determining whether or not to introduce a railway system that utilizes a general-purpose wireless communication system and for controlling communication after introduction, but shows an example of estimating communication quality when measurement at the estimation target location is not possible for some reason.

[0062] FIG. 11 is a block diagram showing an example of the configuration of the measurement condition determination device 102 included in the communication quality estimation device 101 according to the second embodiment. The measurement condition determination device 102 comprises a communication traffic acquisition unit 504 , a measurement time zone acquisition unit 505 , and a measurement position acquisition unit 1102 .

[0063] The measurement position acquisition unit 1102 receives the train operation information 502, the communication condition information 503, and the user capacity information 1101 as input, and outputs the measurement target position. The user capacity information 1101 is information that collects the capacity to accommodate users in a wireless system associated with a location. For example, the information includes the bandwidth of the communication system, the number of component carriers in carrier aggregation, the cell deployment density at the location to be estimated, and the number of base stations. The types and number of user capacity information to be used are not particularly limited, and it is sufficient that at least one parameter is collected.

[0064] 12 is a flowchart showing the overall processing procedure of the measurement position acquisition unit 1102 included in the measurement condition determination device 102 of Example 2. The operation of each processing step will be explained below, but explanations of steps similar to the first processing step (S701) of the flowchart shown in FIG.

[0065] Step S1201: User capacity information at the estimation target location is acquired.

[0066] Step S1202: From the train operation information 502 acquired in step S701, capacity information at locations that are not subject to estimation is acquired.

[0067] Step S1203: A location that is not the estimation target acquired in step S1202 and has a user capacity that is the same as or close to the user capacity at the estimation target location acquired in step S1201 is acquired as the measurement location. Note that when multiple user capacities can be acquired, there is no priority order for these parameters. For example, if the user capacity at the estimation target location is 20 MHz (Hertz) and the number of component carriers is 2, and if location A, which has a user capacity other than the estimation target, has 20 MHz and one component carrier, and location B has 10 MHz and two component carriers, either A or B may be selected as the measurement location.

[0068] In an actual operation mode, for example, if the estimation target position (position C) is not measurable, No is entered in the measurement availability setting 310 for the estimation target position in the setting list 302 of the measurement condition determination device 102, positions A, B, and D are entered as candidate positions where measurement is possible in the measurement target position 304, other measurement conditions are entered, and the measurement condition acquisition start button 311 is activated. The processing of FIG. 12 is then performed, and data associated with positions A and B, which have the same or similar user capacity, is displayed in the measurement condition list in the result list 312 (assuming that the user capacity of position D is different). From there, the measurement target position is determined and communication quality information is measured. Thereafter, in the setting list 402 of the data estimation device 103, No is entered in the relationship between estimation target position and measurement position 408 along with other estimation conditions, position C is entered in the estimation target position 409, and the communication quality estimation start button is activated, and the output result, the result list 411, is acquired. However, the procedure is not limited to this.

[0069] As described above, the second embodiment is characterized in that a communication quality estimation model for communication traffic volume is generated based on measurement information from another location that is equal to the user capacity of the estimation target location, and the model is used for estimation of communication quality at an estimation target location where measurement is not possible. This makes it possible to acquire communication quality under comprehensive communication conditions without having to comprehensively change the location from which communication quality is to be acquired and perform actual measurements.

[0070] [Example 3] Next, a third embodiment of the present invention will be described. However, the description of the third embodiment will focus on differences from the first embodiment. The aspects of the third embodiment that are not particularly mentioned are the same as those of the first embodiment. The third embodiment is intended to estimate communication quality for the purpose of realizing communication control during operation of a railway system that utilizes a general-purpose wireless communication system.

[0071] FIG. 13 is a block diagram showing an example of the physical configuration of the entire railway system in which a communication platform 1302 to which the present invention is applied according to the third embodiment has been introduced. The railway system shown in Figure 13 employs a configuration in which communications related to train operation and customer services are carried out between multiple railway application devices on the ground and on board a moving train via a general-purpose wireless communication system, thereby providing a wireless communication system that realizes safe, accurate, and comfortable railway operation.

[0072] In the general-purpose wireless communication system, application terminal 1301, communication platform 1302, and communication control decision device 1306 are installed on the ground in a communication area where service can be provided, and communication is performed via core network 1303 and wireless access network 1304 with wireless terminal 1305 and application terminal 1301 installed on board the vehicle.

[0073] The application terminal 1301 is a device that transmits and receives data using communication control by the communication platform 1302, and realizes train operations, customer services, and the like.

[0074] The communication control by the communication platform 1302 is, for example, performed in an area where throughput is insufficient, so as to use a communication path that is predicted to have better communication performance. For example, in Fig. 13, if the required communication quality is not met when wireless access network A is used as the communication path, the communication platform 1302 performs communication control to use the path of wireless access network B. In addition, communication control may be performed such as lowering the image quality of transmitted image information.

[0075] The communication control determination device 1306 includes a communication quality estimation device 1307 and a communication control device 1308 .

[0076] The communication quality estimation device 1307 is a device that outputs an estimated value of the communication quality of the railway application to the communication control device 1308. In the third embodiment, the invention particularly focuses on the communication quality estimation device 1307 that estimates the communication quality.

[0077] The communication control device 1308 is a device that determines communication control in the communication platform 1302 based on the estimated value of communication quality obtained from the communication quality estimation device 1307, and delivers setting values ​​related to the communication control to the communication platform 1302. The delivery of the setting values ​​to the on-board communication platform 1302 may use a shared network or a dedicated line.

[0078] FIG. 14 is a block diagram showing an example of the configuration of the communication quality estimation device 1307 included in the communication control determination device 1306 of the third embodiment. The communication quality estimation device 1307 includes a communication information receiving unit 1401 , a past communication information database (hereinafter referred to as DB (DataBase)) 1402 , a communication traffic acquiring unit 504 , and a communication quality estimating unit 603 .

[0079] The communication information receiving unit 1401 acquires communication quality information linked to the first communication traffic volume from the past communication information DB based on the communication condition information 503, and outputs a communication quality estimation model for the first communication traffic volume.

[0080] The past communication information DB 1402 stores information required for a communication quality estimation model for the first communication traffic volume generated in the communication information receiving unit 1401 .

[0081] 15 is a diagram illustrating an example 1501 of a data configuration of information stored in the past communication information DB 1402 in the third embodiment. The past communication information DB 1402 stores items related to communication quality information, such as date and time, location, wireless terminal, wireless system, transmission direction, system bandwidth as user accommodation capacity, and communication traffic volume (first communication traffic volume) as communication quality, as well as throughput linked thereto. The data configuration 1501 is not necessarily limited to the items shown in FIG. 15 as long as it includes items necessary for generating a communication quality estimation model for the first communication traffic volume. Note that the first communication traffic volume stored in the past communication information DB 1402 may be a predicted value or an actually measured value. It is also possible to accumulate, as data, the communication conditions, communication traffic volume, and communication quality information acquired and used when generating the communication quality estimation model in the first or second embodiment in the past communication information DB 1402.

[0082] For example, the first line of data configuration 1501 indicates that at "2022 / 1 / 1 7:00", the wireless system "LTE" present at "Location A" has the capability of transmitting "20 MHz" in the "Down Link" direction, and when the communication traffic volume in the communication area is "100 MBps", the throughput is "10 MBps". Note that, in addition to the system bandwidth, the number of component carriers and the cell placement density in the communication area may also be stored as user accommodation capacity, and there is no restriction on the number and type of parameters to be used. Also, although throughput is shown in Figure 15 as communication quality, there is no restriction on the type of communication quality to be estimated, as long as it is recorded, such as the packet error rate and communication delay time.

[0083] 16 is a flowchart illustrating the overall processing procedure of the communication information receiving unit 1401 included in the communication quality estimation device 1307 according to the third embodiment. The operation of each processing step will be described below, but the description of steps similar to the last processing step (S902) in the flowchart illustrated in FIG. 9 will be omitted.

[0084] Step S1601: The communication conditions, user accommodation capacity, communication traffic volume, and communication quality information linked thereto (hereinafter also referred to as "past communication information data") are acquired from the past communication information DB 1402.

[0085] Step S1602: Search whether past communication information data matching the estimation condition exists. If matching data exists (yes), proceed to step S1603, and if matching data does not exist (no), proceed to step S1604.

[0086] Step S1603: Past communication information data at the location to be estimated that matches in step S1602 is extracted.

[0087] Step S1604: Past communication information data with communication conditions that are the same as or similar to the user capacity at the location to be estimated is searched again in the past communication information DB 1402, and matching data is extracted. This process is performed when past communication information data linked to the location to be estimated does not exist in the past communication information DB 1401. The content of the process is the same as in the second embodiment.

[0088] As described above, the third embodiment is characterized in that, during operation of a railway system, communication quality is estimated even when communication conditions at a location to be estimated are unprecedented. This makes it possible to obtain communication quality even in an environment where lines are predicted to be unprecedentedly congested, thereby realizing appropriate communication control in the communication platform 1302 and realizing safe, accurate, and comfortable train operation without reducing the availability of railway applications.

[0089] Here, the present invention is not limited to the railway systems described in the first to third embodiments. For example, the present invention can also be applied to a system of a moving object that moves along a predetermined route according to a schedule. Although the first to third embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit and scope of the present invention. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, part of the configuration of one embodiment may be replaced with the configuration of another embodiment, or the configuration of another embodiment may be added to the configuration of one embodiment. Furthermore, part of the configuration of each embodiment may be added to, deleted from, or replaced with other configurations. Furthermore, although various information has been exemplified in a table format, this information may also be managed in a format other than a table.

[0090] The following are examples of possible embodiments of the present invention, but the present invention is not limited to these. [Aspect 1] a communication traffic acquisition unit that predicts communication traffic volume based on people flow data under predetermined communication conditions; a communication information receiving unit that generates a communication quality estimation model from a first communication traffic volume and communication quality information linked to the first communication traffic volume; a communication quality estimation unit that estimates communication quality under the estimation conditions from the communication quality estimation model and a second communication traffic volume predicted under the estimation conditions by the communication traffic acquisition unit, A communication quality estimation device that estimates the communication quality of wireless communication used for a mobile object involved in passenger transportation. [Aspect 2] the first communication traffic volume is data predicted by the communication traffic acquisition unit under measurement conditions; 2. The communication quality estimation device according to claim 1. [Aspect 3] a measurement time zone determination unit that determines a measurement time zone based on the measurement conditions and the first communication traffic volume predicted under the measurement conditions; measuring the communication quality information under the measurement conditions in the measurement time period determined by the measurement time period determination unit; The communication quality estimation device according to aspect 2. [Aspect 4] The people flow data includes data on the number of people present at the target location by time period, or data on the number of passengers in a passenger service. The communication quality estimation device according to any one of the first to third aspects. [Aspect 5] the predetermined communication conditions include any one of date and time, location, weather, wireless system, wireless terminal, communication traffic parameters, wireless system fault information, and event information around the target location; The communication quality estimation device according to any one of the first to fourth aspects. [Aspect 6] The communication quality information includes any one of throughput, available bandwidth, communication delay time, and packet error rate. The communication quality estimation device according to any one of the first to fifth aspects. [Aspect 7] a measurement position acquisition unit that determines a position to be measured based on user capacity information at a position to be estimated and user capacity information at a position that is not a position to be estimated; The communication quality estimation device according to any one of the first to sixth aspects. [Aspect 8] The user capacity information includes any one of information regarding a bandwidth of the communication system, a number of component carriers of carrier aggregation, a cell deployment density at the estimation target location, and a number of base stations. 8. The communication quality estimation device according to claim 7. [Aspect 9] a past communication information database that stores the first communication traffic volume and the communication quality information linked to the first communication traffic volume; The communication quality estimation device according to any one of aspects 1 and 4 to 6. [Aspect 10] The past communication information database stores at least communication conditions, user capacity information, communication traffic volume, and communication quality information. 10. The communication quality estimation device according to embodiment 9. [Aspect 11] The wireless communication used for the moving body related to passenger transportation is wireless communication of a railway system using general-purpose wireless. The communication quality estimation device according to any one of the first to tenth aspects. [Aspect 12] a step 1 of generating a communication quality estimation model from a first communication traffic volume and communication quality information linked to the first communication traffic volume; Step 2 of predicting a second communication traffic volume based on people flow data under the estimated conditions; a step 3 of estimating communication quality under the estimation conditions from the communication quality estimation model and the second communication traffic volume, A communication quality estimation method for estimating the communication quality of wireless communication used in a mobile object involved in passenger transportation. [Aspect 13] A communication quality estimation program having instructions for causing a processor to execute steps 1 to 3 of the communication quality estimation method according to aspect 12. [Explanation of symbols]

[0091] 101... communication quality estimation device, 102... measurement condition determination device, 103... data estimation device, 104...Data acquisition device, 201...Processor (CPU), 202...Memory, 203...Input 1 / F, 204... Auxiliary storage device, 205... Communication I / F, 206... Output I / F, 504...communication traffic acquisition unit, 505...measurement time zone acquisition unit, 602...communication information receiving unit, 603...communication quality estimating unit, 1102…Measurement position acquisition unit, 1301... application terminal, 1302... communication platform, 1303... core network 1304...wireless access network, 1305...wireless terminal, 1306... communication control determination device, 1307... communication quality estimation device, 1308... communication control device 1401... communication information receiving unit, 1402... past communication information DB

Claims

1. a communication traffic acquisition unit that predicts communication traffic volume based on people flow data under predetermined communication conditions; a communication information receiving unit that generates a communication quality estimation model from a first communication traffic volume and communication quality information linked to the first communication traffic volume; a communication quality estimation unit that estimates communication quality under the estimation conditions from the communication quality estimation model and a second communication traffic volume predicted under the estimation conditions by the communication traffic acquisition unit, The people flow data includes data on the number of people present at the target location by time period, or data on the number of passengers in a passenger service. A communication quality estimation device that estimates the communication quality of wireless communication used for a mobile object involved in passenger transportation.

2. the first communication traffic volume is data predicted by the communication traffic acquisition unit under measurement conditions; The communication quality estimation device according to claim 1 .

3. a measurement time zone determination unit that determines a measurement time zone based on the measurement conditions and the first communication traffic volume predicted under the measurement conditions; measuring the communication quality information under the measurement conditions in the measurement time period determined by the measurement time period determination unit; The communication quality estimation device according to claim 2 .

4. the predetermined communication conditions include any one of date and time, location, weather, wireless system, wireless terminal, communication traffic parameters, wireless system fault information, and event information around the target location; The communication quality estimation device according to any one of claims 1 to 3.

5. The communication quality information includes any one of throughput, available bandwidth, communication delay time, and packet error rate. The communication quality estimation device according to any one of claims 1 to 3.

6. a measurement position acquisition unit that determines a position to be measured based on user capacity information at a position to be estimated and user capacity information at a position that is not a position to be estimated; The communication quality estimation device according to any one of claims 1 to 3.

7. The user capacity information includes any one of information regarding a bandwidth of the communication system, a number of component carriers of carrier aggregation, a cell deployment density at the estimation target location, and a number of base stations. The communication quality estimation device according to claim 6.

8. a past communication information database that stores the first communication traffic volume and the communication quality information linked to the first communication traffic volume; The communication quality estimation device according to claim 1 .

9. The past communication information database stores at least communication conditions, user capacity information, communication traffic volume, and communication quality information. The communication quality estimation device according to claim 8 .

10. The wireless communication used for the moving body related to passenger transportation is wireless communication of a railway system using general-purpose wireless. The communication quality estimation device according to any one of claims 1 to 3, 8 and 9.

11. a step 1 of generating a communication quality estimation model from a first communication traffic volume and communication quality information linked to the first communication traffic volume; Step 2 predicts a second communication traffic volume based on people flow data including either data on the number of people present at a target location by time period or data on the number of passengers of a passenger service under an estimation condition; a step 3 of estimating communication quality under the estimation conditions from the communication quality estimation model and the second communication traffic volume, A communication quality estimation method for estimating the communication quality of wireless communication used in a mobile object involved in passenger transportation.

12. A communication quality estimation program having instructions for causing a processor to execute steps 1 to 3 in the communication quality estimation method according to claim 11.

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