Measurement system, moving vehicle, measurement method, and measurement program

Abstract

A measurement system according to an embodiment of the present invention comprises a moving vehicle that receives radio waves transmitted by a base station, said system measuring the propagation characteristics of the radio waves. A plurality of radio wave measurement positions are set within an area of interest, including at the edges of the area of interest, where the propagation characteristics of radio waves transmitted by the base station are to be measured by the moving vehicle. The shortest route that sequentially passes through each of the measurement positions is calculated, and the moving vehicle is made to move in accordance with the calculated shortest route. When the moving vehicle passes through each of the measurement positions, radio waves transmitted by the base station are received, the propagation characteristics of the received radio waves are measured, and the measured propagation characteristics of the radio waves are used as a basis for data interpolation of the propagation characteristics of radio waves throughout the entire area of interest, using an interpolation method that follows radial basis functions.

Description

Measurement system, moving body, measurement method and measurement program

[0001] The present invention relates to a measurement system, a moving object, a measurement method, and a measurement program.

[0002] In recent years, new wireless communication systems, such as 5G and local 5G, have been introduced. In order to provide these wireless communication systems with high quality, it is important to install the optimal wireless base station for the wireless communication system. Methods for this include evaluation using propagation simulation and on-site wireless propagation characteristic surveys.

[0003] Conventionally, in on-site radio propagation surveys, a person typically holds a radio and measures the area of ​​interest. However, this method has drawbacks in terms of manpower and work time. Therefore, to improve the efficiency of measurement work, studies are being conducted to install a radio on an automated vehicle such as an AGV (Automated Guided Vehicle) and automatically measure radio wave propagation characteristics (see, for example, Non-Patent Document 1).

[0004] Issei Makino and two others, "Indoor Local 5G Wireless Performance Measurement Using Automated Guided Vehicles", Institute of Electronics, Information and Communication Engineers, IEICE Technical Report, 2021, pp. 34-39

[0005] When measuring radio wave propagation with high accuracy using autonomous vehicles such as AGVs, it is necessary to significantly increase the number of measurement points within the target area. Furthermore, wireless communication systems such as 5G are increasingly using radio waves in the high-frequency band. As a result, the short wavelength of radio waves requires finer measurement intervals, and measurement points need to be three-dimensional to diversify use cases. This increases the number of measurement points, which significantly increases measurement time, posing a challenge.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a measurement system, a mobile body, a measurement method, and a measurement program that can efficiently measure the propagation characteristics of radio waves within a target area.

[0007] A measurement system according to one embodiment of the present invention is a measurement system that measures the propagation characteristics of radio waves and is equipped with a mobile body that receives radio waves transmitted from a base station.The measurement system is characterized in that the mobile body has a route control unit that sets multiple measurement positions for radio waves, including the edges of a target area, within the target area where the propagation characteristics of the radio waves transmitted from the base station are to be measured, and calculates the shortest route that passes through each of the measurement positions in sequence; an automatic operation unit that moves the mobile body along the shortest route calculated by the route control unit; a receiving unit that receives the radio waves transmitted from the base station as the mobile body passes each of the measurement positions and measures the propagation characteristics of the received radio waves; and a data interpolation unit that interpolates data on the propagation characteristics of radio waves for the entire target area using an interpolation method that follows a radial basis function, based on the propagation characteristics of the radio waves measured by the receiving unit.

[0008] Furthermore, a mobile body according to one embodiment of the present invention is characterized in that the mobile body moves while measuring the propagation characteristics of radio waves transmitted by a base station, and includes: a travel route control unit that sets a plurality of measurement positions for radio waves, including an edge of a target area, within the target area where the propagation characteristics of the radio waves transmitted by the base station are to be measured, and calculates the shortest route that passes through each of the measurement positions in sequence; an automatic travel unit that moves the mobile body along the shortest route calculated by the travel route control unit; a receiving unit that receives radio waves transmitted by the base station when the mobile body passes each of the measurement positions and measures the propagation characteristics of the received radio waves; and a data interpolation unit that interpolates data on the propagation characteristics of radio waves for the entire target area using an interpolation method that follows a radial basis function, based on the propagation characteristics of the radio waves measured by the receiving unit.

[0009] Furthermore, a measurement method according to one embodiment of the present invention is a measurement method performed by a measurement system that includes a mobile body that receives radio waves transmitted from a base station and measures the propagation characteristics of radio waves, and is characterized in that the mobile body performs the following steps: a route control step in which the mobile body sets a plurality of measurement positions for radio waves, including the edge of the target area, within the target area where the propagation characteristics of the radio waves transmitted from the base station are to be measured, and calculates the shortest route that passes through each of the measurement positions in sequence; an automatic operation step in which the mobile body moves along the calculated shortest route; a reception step in which the mobile body receives radio waves transmitted from the base station as the mobile body passes each of the measurement positions and measures the propagation characteristics of the received radio waves; and a data interpolation step in which the propagation characteristics of the radio waves for the entire target area are interpolated using an interpolation method that follows a radial basis function based on the measured propagation characteristics of the radio waves.

[0010] In addition, a measurement program according to one embodiment of the present invention is a measurement program executed by a mobile body that moves while measuring the propagation characteristics of radio waves transmitted by a base station, and includes an operation route control unit that sets multiple measurement positions for radio waves including the edges of a target area within the target area where the propagation characteristics of the radio waves transmitted by the base station are to be measured, and calculates the shortest route that passes through each of the measurement positions in sequence; an automatic operation unit that moves the mobile body along the shortest route calculated by the operation route control unit; a receiving unit that receives radio waves transmitted by the base station when the mobile body passes each of the measurement positions and measures the propagation characteristics of the received radio waves; and a data interpolation unit that interpolates data of the propagation characteristics of radio waves for the entire target area using an interpolation method that follows a radial basis function based on the propagation characteristics of the radio waves measured by the receiving unit.

[0011] According to the present invention, it is possible to efficiently measure the propagation characteristics of radio waves within a target area.

[0012] FIG. 1 is a diagram illustrating an overview of a measurement system according to an embodiment; FIG. 2 is a block diagram illustrating an example of the configuration of a measurement system; FIG. 3 is a diagram illustrating an example of the shortest route that sequentially passes through measurement positions of multiple radio waves, including the edge of a target area; FIG. 4 is a diagram illustrating an obstacle that creates a non-line-of-sight area and the boundary (boundary area) of an area where the propagation model differs; FIG. 5 is a diagram illustrating a travel route when the periphery of a base station is included in the travel route as a measurement position; FIG. 6 is a flowchart illustrating an example of the operation of a measurement system according to an embodiment; and FIG. 7 is a diagram illustrating an example of the hardware configuration of a mobile object according to an embodiment. (a) is a diagram illustrating an overview of a target area for measuring propagation characteristics and a measurement system. (b) is a diagram illustrating an example of a received power map of radio waves measured by the measurement system.

[0013] First, the background to the invention will be described. Fig. 8 is a diagram showing an overview of a measurement system 1 for measuring propagation characteristics of radio waves used in wireless communication. Fig. 8(a) is a diagram showing a target area for measuring propagation characteristics and an overview of the measurement system 1. Fig. 8(b) is a diagram showing an example of a received power map 5 of radio waves measured by the measurement system 1.

[0014] 8(a), in a measurement system 1 for measuring the propagation characteristics of radio waves used in wireless communication, for example, a mobile object 3 such as an AVG moves along an automatic driving route 4 within a target area 100 where the propagation characteristics of radio waves transmitted by a base station (wireless base station) 2 are to be measured. The mobile object 3 is provided with a receiver (not shown) and has the function of measuring the propagation characteristics of radio waves while moving.

[0015] The propagation characteristics of the radio waves measured by the mobile object 3 are visualized, for example, as a received power map shown in Fig. 8(b) . At this time, data for areas other than the measurement points where the mobile object 3 measured the radio waves within the target area 100 is interpolated using the results of measurements made by the mobile object 3.

[0016] Next, a measurement system that enables efficient measurement of the propagation characteristics of radio waves used in wireless communication will be described in detail.

[0017] Fig. 1 is a diagram showing an overview of a measurement system 10 according to one embodiment. As shown in Fig. 1, the measurement system 10 according to one embodiment includes, for example, a base station 20 and a mobile object 30 that receives radio waves transmitted from the base station 20. It is assumed that the settings of each device included in the measurement system 10 have been completed in advance.

[0018] The mobile body 30 is, for example, a measurement robot that has the function of an AVG for the target area 100 and is capable of automatically traveling along the automatic traveling route 4, or a measurement robot such as a drone that is capable of automatically traveling to any three-dimensional position within the three-dimensional measurement target area 102.

[0019] Fig. 2 is a block diagram showing an example configuration of the measurement system 10. As shown in Fig. 2, the measurement system 10 includes, for example, a base station 20 and a mobile object 30. The mobile object 30 measures the propagation characteristics of radio waves (target radio waves) transmitted by the base station 20.

[0020] The mobile object 30 also includes, for example, a driving route control unit 300 , an automatic driving unit 302 , a measurement unit (receiving unit) 304 , a data interpolation unit 305 , and a visualization unit 306 .

[0021] The driving route control unit 300 functions as a driving route control unit that sets multiple radio wave measurement positions, including the edges of the target area, within the target area where the propagation characteristics of the radio waves transmitted by the base station 20 are measured, and controls the driving route according to a policy that calculates the shortest route that passes through each of the measurement positions in sequence.

[0022] 3 is a diagram illustrating an example of a shortest route that sequentially passes through multiple radio wave measurement positions that include the edges of the target area 100. As shown in FIG. 3, the travel route control unit 300 calculates the shortest route that includes the edges of the target area 100 (for example, the four corners of a rectangular target area) as measurement positions, and controls the travel route.

[0023] In addition, the driving route control unit 300 may perform control so that boundary areas with different propagation models (line of sight and non-line of sight areas, presence or absence of multipath, height, environmental fluctuations, surrounding materials, etc.) are included as measurement locations on the driving route.

[0024] 4 is a diagram showing a schematic diagram of an obstacle that causes a non-line-of-sight area and a boundary (boundary area) of an area where the propagation model differs. The driving route control unit 300 sets measurement positions not only at the edges (corners) of the target area but also on the boundary area shown in FIG.

[0025] The travel route control unit 300 may also perform control so that the vicinity of the base station 20 is included on the travel route as a measurement position.

[0026] 5 is a diagram schematically illustrating a travel route when the vicinity of the base station 20 is included on the travel route as a measurement position. The travel route control unit 300 sets measurement positions not only at the edges (corners) of the target area but also, for example, in the vicinity of the base station 20 shown in FIG. 5 (the area surrounded by the dashed ellipse).

[0027] The automatic driving unit 302 (FIG. 2) functions as an automatic operation unit that moves the mobile object 30 along the shortest route calculated by the driving route control unit 300 .

[0028] The measurement unit 304 functions as a receiver that receives radio waves transmitted from the base station 20 when the mobile unit 30 passes through each measurement position and measures the propagation characteristics of the received radio waves (received power, throughput, delay profile, fading, etc.) The measurement unit 304 may be equipped with an omnidirectional antenna or a directional antenna.

[0029] The data interpolation unit 305 interpolates data on the propagation characteristics of radio waves for the entire target area using an interpolation method that follows, for example, a radial basis function of received power, based on the propagation characteristics of radio waves measured by the measurement unit 304. Specifically, the data interpolation unit 305 performs data interpolation on areas within the target area that are not measurement positions.

[0030] The visualization unit 306 visualizes the propagation characteristics of radio waves over the entire target area using a propagation characteristics map or the like, using the results of data interpolation performed by the data interpolation unit 305. Note that the visualization unit 306 may be provided in an external device or the like.

[0031] Next, an operation example of the measurement system 10 will be described. Fig. 6 is a flowchart showing an operation example of the measurement system 10 according to one embodiment. As shown in Fig. 6, in the measurement system 10, for example, the mobile object 30 analyzes target area information (S100) and calculates a travel route (shortest route) of the mobile object 30 (S102).

[0032] The mobile unit 30 automatically measures the propagation characteristics of the radio waves transmitted by the base station 20 (S104).

[0033] Then, the moving body 30 determines whether measurements have been completed at all measurement locations along the travel route (S110), and if not (S110: No), returns to processing S104, and if completed (S110: Yes), proceeds to processing S112.

[0034] In the process of S112, the mobile object 30 performs data interpolation of the propagation characteristics of radio waves for the entire target area based on the measured propagation characteristics of radio waves using an interpolation method that follows, for example, a radial basis function.

[0035] In the process of S114, the mobile body 30 uses the results of the data interpolation to visualize the propagation characteristics of radio waves for the entire target area using a propagation characteristics map or the like.

[0036] In other words, the measurement system 10 can obtain the propagation characteristics (received power, throughput, delay profile, fading) of radio waves within a target area with high accuracy using limited measurement locations, while also shortening the measurement time.

[0037] In this way, the measurement system 10 uses the results of data interpolation to visualize the propagation characteristics of radio waves throughout the entire target area, thereby enabling the propagation characteristics of radio waves within the target area to be measured efficiently.

[0038] In addition, each function possessed by the above-mentioned mobile body 30 may be configured in part or in whole by hardware such as a PLD (Programmable Logic Device) or an FPGA (Field Programmable Gate Array), or may be configured as a program executed by a processor such as a CPU.

[0039] For example, the mobile unit 30 can be realized using a computer and a program, and the program can be recorded on a storage medium or provided via a network.

[0040] 7 is a diagram showing an example of the hardware configuration of a mobile object 30 according to an embodiment. As shown in FIG. 7, the mobile object 30 has an input unit 600, an output unit 601, a communication unit 602, a CPU 603, a memory 604, and an HDD 605 connected via a bus 606, and thus has the functionality of a computer. The mobile object 30 is also capable of inputting and outputting data to and from a computer-readable storage medium 607.

[0041] The input unit 600 is, for example, a keyboard and a mouse. The output unit 601 is, for example, a display device. The communication unit 602 is a communication interface for performing communication.

[0042] The CPU 603 controls each component of the mobile object 30 and performs predetermined processing, etc. The memory 604 and HDD 605 store data, etc.

[0043] The storage medium 607 is capable of storing programs and the like that cause the mobile unit 30 to execute the functions of the mobile unit 30. Note that the architecture that configures the mobile unit 30 is not limited to the example shown in FIG.

[0044] 1... measurement system, 2... base station, 3... mobile body, 4... automatic driving route, 5... reception power map, 10... measurement system, 20... base station, 30... mobile body, 100... target area, 300... driving route control unit, 302... automatic driving unit, 304... measurement unit, 305... data interpolation unit, 306... visualization unit, 600... input unit, 601... output unit, 602... communication unit, 603... CPU, 604... memory, 605... HDD, 606... bus, 607... storage medium

Claims

1. A measurement system for measuring radio wave propagation characteristics comprising a mobile body that receives radio waves transmitted from a base station, wherein the mobile body has: a route control unit that sets a plurality of measurement positions for radio waves including edges of a target area within which the propagation characteristics of the radio waves transmitted from the base station are to be measured, and calculates the shortest route that passes through each of the measurement positions in sequence; an automatic operation unit that moves the mobile body along the shortest route calculated by the route control unit; a receiving unit that receives radio waves transmitted from the base station and measures the propagation characteristics of the received radio waves when the mobile body passes each of the measurement positions; and a data interpolation unit that performs data interpolation of the radio wave propagation characteristics for the entire target area based on the propagation characteristics of the radio waves measured by the receiving unit using an interpolation method according to a radial basis function.

2. A mobile body that moves while measuring the propagation characteristics of radio waves transmitted by a base station, comprising: a driving route control unit that sets a plurality of measurement positions for radio waves including the edges of a target area within which the propagation characteristics of the radio waves transmitted by the base station are measured, and calculates the shortest route that passes through each of the measurement positions in sequence; an automatic driving unit that moves the mobile body along the shortest route calculated by the driving route control unit; a receiving unit that receives radio waves transmitted by the base station and measures the propagation characteristics of the received radio waves when the mobile body passes each of the measurement positions; and a data interpolation unit that performs data interpolation of the propagation characteristics of radio waves for the entire target area based on the propagation characteristics of the radio waves measured by the receiving unit using an interpolation method that follows a radial basis function.

3. A measurement method performed by a measurement system having a mobile body that receives radio waves transmitted from a base station and that measures radio wave propagation characteristics, wherein the mobile body performs the following steps: a navigation route control step for setting a plurality of radio wave measurement positions including the edges of a target area within which the propagation characteristics of the radio waves transmitted from the base station are to be measured, and calculating the shortest route that passes through each of the measurement positions in sequence; an automatic navigation step for moving the mobile body according to the calculated shortest route; a reception step for receiving radio waves transmitted from the base station and measuring the propagation characteristics of the received radio waves as the mobile body passes through each of the measurement positions; and a data interpolation step for interpolating data of the radio wave propagation characteristics for the entire target area based on the measured propagation characteristics of the radio waves using an interpolation method according to a radial basis function.

4. A measurement program executed by a moving object while measuring the propagation characteristics of radio waves transmitted by a base station, comprising: a driving route control unit which sets a plurality of measurement positions for radio waves including the edges of a target area within which the propagation characteristics of the radio waves transmitted by the base station are to be measured, and calculates the shortest route that passes through each of the measurement positions in sequence; an automatic driving unit which moves the moving object along the shortest route calculated by the driving route control unit; a receiving unit which receives radio waves transmitted by the base station and measures the propagation characteristics of the received radio waves when the moving object passes through each of the measurement positions; and a data interpolation unit which performs data interpolation of the propagation characteristics of radio waves for the entire target area based on the propagation characteristics of the radio waves measured by the receiving unit using an interpolation method according to a radial basis function.

Images