Coverage measurement device for base station, terminal, and coverage measurement method for base station

Abstract

This coverage measurement device for a base station is characterized by including: first position information indicating the position of a first point at a first time by a measurer carrying a terminal that communicates with a plurality of base stations; second position information indicating the position of a second point at which the measurer is located at a second time; an acquisition unit for acquiring one or more pieces of sensor information output from one or more sensors of the terminal in a period from the first time to the second time; an interpolation unit for outputting estimated position information in which the position of the terminal is estimated by interpolating the position of the terminal in the period on the basis of the one or more pieces of sensor information; and a determination unit for determining, on the basis of the estimated position information, the coverage of the base station that has communicated with the terminal during the period.

Description

Base station coverage area measurement device, terminal, and base station coverage area measurement method

[0001] The present disclosure relates to a base station coverage area measuring device, a terminal, and a base station coverage area measuring method.

[0002] Theoretically, the coverage area of ​​a base station for providing mobile communication services can be confirmed by simulation, but in reality, the accurate coverage area cannot be determined without conducting a field survey. In a field survey of the coverage area of ​​a base station, it is necessary to sequentially record and measure pairs of the position of the measurement point and identification information that uniquely identifies the base station for each of multiple measurement points. The positions of the measurement points can be measured, for example, using a Global Positioning System (GPS) or a Global Positioning Satellite (see, for example, Patent Document 1).

[0003] JP 2013-7661 A

[0004] Since GPS signals may not be received underground or in high-rise buildings, it is possible for the measurer to input his / her current location using a map. However, there is a problem in that it is time-consuming for the measurer to input his / her own location frequently (for example, every second).

[0005] An object of the present disclosure is to enable accurate measurement of the coverage area of ​​a base station for providing mobile communication services while reducing the burden on the person performing the measurement.

[0006] A base station coverage range measuring device according to one aspect of the present disclosure includes first location information indicating the location of a first point where a measurer carrying a terminal that communicates with multiple base stations is located at a first time; second location information indicating the location of a second point where the measurer is located at a second time; an acquisition unit that acquires one or more pieces of sensor information output from one or more sensors of the terminal during a period from the first time to the second time; an interpolation unit that outputs estimated location information that estimates the location of the terminal by interpolating the location of the terminal during the period based on the sensor information; and a determination unit that determines the coverage range of base stations with which the terminal communicated during the period based on the estimated location information.

[0007] a first recording unit that records first date and time information indicating a location of a first point where a measurer is located at a first time in association with first location information indicating the first time, and records second date and time information indicating the second time in association with second location information indicating a location of a second point where the measurer is located at a second time; a second recording unit that records at least one pair of identification information indicating a base station with which the measurer communicated using the communication unit among the plurality of base stations during a period from the first time to the second time, and third date and time information indicating a time at which the identification information was acquired; and a transmission unit that transmits the pair of the first location information and the first date and time information, the pair of the second location information and the second date and time information, at least one pair of the identification information and the third date and time information, and one or more pieces of sensor information output from the one or more sensors during the period from the first time to the second time, to a coverage range measurement device that measures the coverage range of each of the plurality of base stations.

[0008] A method for measuring the coverage range of a base station according to one aspect of the present disclosure includes: acquiring first location information indicating the location of a first point where a person carrying a terminal that communicates with a plurality of base stations is located at a first time; second location information indicating the location of a second point where the person is located at a second time; acquiring one or more pieces of sensor information output from one or more sensors of the terminal during a period from the first time to the second time; outputting estimated location information that estimates the location of the terminal by interpolating the location of the terminal during the period based on the sensor information; and determining the coverage range of base stations with which the terminal communicated during the period based on the estimated location information.

[0009] According to one aspect of the present disclosure, it is possible to accurately measure the coverage area of ​​a base station for providing mobile communication services while reducing the burden on the person performing the measurement.

[0010] 1 is a block diagram showing a configuration of a communication system 1 including a coverage range measurement device 20 according to an embodiment of the present disclosure. FIG. 1 is a diagram showing an example of a configuration of a terminal 10. FIG. 2 is a diagram showing an example of a UI screen G1. FIG. 3 is a diagram showing an example of a first management table TBL1. FIG. 4 is a diagram showing an example of a second management table TBL2. FIG. 5 is a flowchart showing the flow of a recording method executed by a processing device 160 of the terminal 10 according to a program PR1. FIG. 1 is a diagram showing an example of a configuration of the coverage range measurement device 20. FIG. 2 is a diagram showing an example of a third management table TBL3. FIG. 3 is a diagram showing an example of a fourth management table TBL4. FIG. 4 is a diagram showing an example of a fifth management table TBL5. FIG. 5 is a diagram for explaining processing executed by a determination unit 260c. FIG. 6 is a diagram showing an example of an image displayed on a display device 220 by a display control unit 260d. FIG. 6 is a flowchart showing the flow of a coverage range measurement method executed by a processing device 260 of the terminal 10 according to a program PR2. FIG. 7 is a diagram for explaining the operation of the modification (2). FIG. 8 is a diagram for explaining the modification (3). FIG. 9 is a diagram for explaining the modification (5).

[0011] A. Embodiment A-1: ​​Overall Configuration FIG. 1 is a diagram illustrating the configuration of a communication system 1 including a coverage range measurement device 20 according to an embodiment of the present disclosure. The communication system 1 includes a terminal 10 that communicates with the coverage range measurement device 20 via a communication network NW via wired or wireless connections. The terminal 10 is, for example, a mobile terminal such as a smartphone. The terminal 10 wirelessly communicates with base stations 30(1), 30(2), ... 30(N) that provide mobile communication services. N is an integer greater than or equal to 2. The base station 30(1) is an example of a first base station, and the base station 30(2) is an example of a second base station. Hereinafter, when it is not necessary to distinguish between the base stations 30(1), 30(2), ... 30(N), each base station 30(1), 30(2), ... 30(N) will be referred to as a "base station 30." For example, an area in a city, ward, town, village, or other area where mobile communication services are available is referred to as a service area. A service area is covered by multiple base stations 30. The service area is further divided into smaller areas called cells. One base station 30 covers multiple cells. The coverage area of ​​a base station 30 is the area where wireless communication with the base station 30 is possible. The terminal 10 is a device for measuring the coverage area of ​​each of the multiple base stations 30 by field survey.

[0012] A-2: Configuration of Terminal 10 Fig. 2 is a diagram showing an example configuration of the terminal 10. As shown in Fig. 2, the terminal 10 includes a communication device 110, a display device 120, an input device 130, a sensor 140, a storage device 150, a processing device 160, and a bus 170 that interconnects these devices.

[0013] The communication device 110 includes a communication circuit and an antenna for wireless communication with the base station 30. The communication device 110 is also connected wirelessly to the communication network NW. The communication device 110 communicates with other devices connected to the communication network NW. An example of such other devices is the coverage range measurement device 20. The communication device 110 may also include a communication interface for performing wired communication with other devices via, for example, a USB (Universal Serial Bus) cable. When the communication device 110 includes such a communication interface, the coverage range measurement device 20 may be wiredly connected to the communication device 110 via a USB cable.

[0014] The display device 120 displays information to the outside under the control of the processing device 160. The display device 120 is, for example, one of various display panels such as a liquid crystal display panel or an organic EL display panel.

[0015] In this embodiment, the display device 120 displays an image of a UI screen G1 under the control of the processing device 160. The UI screen G1 includes an image of a map of an area that is the target of a field survey of the coverage area of ​​the base station 30. Hereinafter, the area that is the target of the field survey will be referred to as the "target area." FIG. 3 is a diagram showing an example of the UI screen G1. Map information representing the map included in the UI screen G1 may be downloaded to the terminal 10 prior to the execution of the field survey, or may be downloaded to the terminal 10 when the field survey is started. The map information also includes correspondence information. The correspondence information associates a position on the map image represented by the map information with latitude and longitude representing a position in real space.

[0016] The input device 130 is an input device that accepts input from outside. Specific examples of the input device 130 include a keyboard, a mouse, a switch, or a button. The input device 130 may be a touch sensor that is integrated with the display device 120 to form a touch panel. A measurer who uses the terminal 10 to measure the coverage area of ​​the base station 30 performs a position designation operation on the input device 130 multiple times while carrying the terminal 10 and walking within the target area. The position designation operation is an operation for designating a position within the target area. In this embodiment, the position designation operation is an operation for designating the measurer's position in the target area by touching the input device 130 on the map image included in the UI screen G1.

[0017] The sensor 140 is, for example, a three-axis acceleration sensor orthogonal to each other. The sensor 140 outputs sensor information representing acceleration in each axis direction generated by the walking of the person carrying the terminal 10 to the processing device 160. As will be described in detail later, the processing device 160 determines the number of steps taken by the person taking the step during a period from when a position designation operation is performed until the next position designation operation, based on the sensor information output from the sensor 140. The time at which the period begins is a first time. The time at which the period ends is a second time. The position of the person taking the step at the first time, i.e., the position of the terminal 10 in real space at the first time, is a first point. The position of the person taking the step at the second time, i.e., the position of the terminal 10 in real space at the second time, is a second point. As will be described in detail later, the processing device 160 calculates the distance traveled by the terminal 10 from the first point to the second point by multiplying the number of steps taken by the person taking the step during the period by the stride length. The stride length is an actual measured value of the stride length of the person taking the terminal 10. The stride length may also be estimated based on parameters such as the gender, age, and height of the person measuring. The person measuring may input the parameters using the input device 130. The average movement speed of the terminal 10 during the period from the first time to the second time is calculated by dividing the movement distance by the length of time between the first time and the second time.

[0018] The timekeeping device 180 is a real-time clock including a quartz crystal oscillator and an oscillation circuit, and outputs time information indicating the current date and time to the processing device 160.

[0019] The storage device 150 is a recording medium readable by the processing device 160. The storage device 150 includes, for example, a nonvolatile memory and a volatile memory. The nonvolatile memory is, for example, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), and an electrically erasable programmable read-only memory (EEPROM). The volatile memory is, for example, a random access memory (RAM). The storage device 150 stores a first management table TBL1, a second management table TBL2, movement speed information D1, and a program PR1. The first management table TBL1, the second management table TBL2, and the movement speed information D1 are stored in the storage device 150 each time a first location and a second location are specified. The movement speed information D1 represents the average movement speed of the terminal 10 from the first location to the second location. The first management table TBL1, the second management table TBL2, and the movement speed information D1 may be stored in an SD card attached to the terminal 10.

[0020] FIG. 4 is a diagram showing an example of a first management table TBL1. The first management table TBL1 stores location information indicating the location where the terminal 10 was located at the date and time represented by the date and time information, in association with date and time information representing each of a first time and a second time. The date and time information indicating the first time is an example of first date and time information. The date and time information indicating the second time is an example of second date and time information. The location information indicating the location of the terminal 10 at the first time, i.e., the location of the first point, is an example of first location information. The location information indicating the location of the terminal 10 at the second time, i.e., the location of the second point, is an example of second location information. The location information in this embodiment represents the latitude and longitude of the location where the terminal 10 was located at the date and time represented by the date and time information. The stored contents of the first management table TBL1 shown in FIG. 4 indicate that the first time is 2:00 PM on July 27, 2023, and the second time is 2:00 PM, 36 seconds on July 27, 2023. Furthermore, the contents stored in the first management table TBL1 shown in Figure 4 indicate that at the first time, the terminal 10 is located at a latitude of "43.060219" and a longitude of "141.352120", and at the second time, the terminal 10 is located at a latitude of "43.060" and a longitude of "141.352".

[0021] FIG. 5 is a diagram illustrating an example of the second management table TBL2. As shown in FIG. 5, the second management table TBL2 stores identification information in association with date and time information indicating a date and time. The date and time information stored in the second management table TBL2 in association with the identification information is an example of third date and time information. The identification information is a unique number assigned to each base station 30 to identify each of the base stations 30(1), 30(2), ... 30(N). A specific example of the identification information is a CID (Cell ID). The identification information stored in the second management table TBL2 in association with date and time information indicates the base station 30 with which the terminal 10 was communicating on the date and time indicated by the date and time information. Note that when the base station 30(2) is located adjacent to the base station 30(1), a portion of the coverage area of ​​the base station 30(1) may overlap a portion of the coverage area of ​​the base station 30(2). Generally, the farther a point is from the base station 30, the weaker the strength of the radio waves transmitted from the base station 30. If the terminal 10 is located in an area where a portion of the coverage area of ​​the base station 30(1) overlaps a portion of the coverage area of ​​the base station 30(2), the terminal 10 communicates with the base station 30(1) if the strength of the radio waves received from the base station 30(1) is stronger than the strength of the radio waves received from the base station 30(2). Conversely, if the strength of the radio waves received from the base station 30(2) is stronger than the strength of the radio waves received from the base station 30(1), the terminal 10 communicates with the base station 30(2). Therefore, as the terminal 10 moves, the base station 30 communicating with the terminal 10 may be switched. In this embodiment, during the period from the first time to the second time, a pair of date and time information and identification information is stored in the second management table TBL2 every time a unit time elapses from the first time. In this embodiment, the unit time is, for example, one second. However, the unit time may be a time length shorter than one second. Furthermore, the unit time may be a time length longer than one second. 5 indicates that the first time is 2:00 PM on July 27, 2023, and that at this first time and at each time 1 second, 2 seconds, and so on, the terminal 10 communicated with the base station 30 having the identification information "19478375." In this embodiment, "19478375" is the identification information of the base station 30(1).

[0022] The processing device 160 includes one or more central processing units (CPUs). The one or more CPUs are an example of one or more processors. Each of the processors and CPUs is an example of a computer. The processing device 260 reads a program PR1 from the storage device 150. By executing the read program PR1, the processing device 160 functions as a display control unit 160a, a first recording unit 160b, a second recording unit 160c, a third recording unit 160d, and a transmission unit 160e.

[0023] The display control unit 160a displays the above-mentioned UI screen G1 on the display device 120. When the measurer performs a position designation operation, the display control unit 160a displays a mark at the position on the map designated by the measurer. A black circle is an example of the mark.

[0024] Each time a position designation operation is performed, the first recording unit 160b converts the position on the map designated by the measurer into a position in real space based on the correspondence information described above. The first recording unit 160b associates the position information representing the position in real space with date and time information indicating the date and time the operation was performed, and stores the associated information in the first management table TBL1.

[0025] The second recording unit 160c stores date and time information and identification information indicating the base station 30 with which the terminal 10 was communicating at the date and time indicated by the date and time information in the second management table TBL2 each time a unit time elapses from the first time during the period from the first time to the second time.

[0026] The third recording unit 160d determines the number of steps taken by the person taking the measure based on the sensor information output from the sensor 140 during the period from the first time to the second time. The third recording unit 160d calculates the distance traveled by the terminal 10 during that period by multiplying the number of steps taken during the period from the first time to the second time by the stride length of the person taking the measure. The calculated distance is the travel distance of the terminal 10. If the terminal 10 moves along a straight line connecting the first point and the second point, the travel distance of the terminal 10 matches the distance between the first point and the second point. On the other hand, if the terminal 10 does not move along the straight line, the travel distance of the terminal 10 does not match the distance between the first point and the second point. For example, suppose the first point and the second point are located on a curved road, and the person carrying the terminal 10 walks along the road. In this assumption, the travel distance of the terminal 10 does not match the distance between the first point and the second point. The third recording unit 160d calculates movement speed information D1 that indicates the average movement speed of the terminal 10 during the period from the first time to the second time by dividing the movement distance by the length of time from the first time to the second time. The third recording unit 160d stores the calculated movement speed information D1 in the storage device 150.

[0027] When an input instructing the transmission of measurement results is made to the input device 130, the transmitting unit 160e transmits a set of date and time information and location information stored in the first management table TBL1, a set of date and time information and identification information stored in the second management table TBL2, and movement speed information D1 to the coverage range measuring device 20 using the communication device 110.

[0028] The processing device 160, which has started executing the program PR1, functions as the display control unit 160a and displays the above-mentioned UI screen G1 on the display device 120. Figure 6 is a flowchart showing the processing flow of this recording method. As shown in Figure 6, this recording method includes the processing of steps SA110 to SA190.

[0029] In step SA110, the processing device 160 determines whether or not a position designation operation has been detected. If a position designation operation has been detected, the determination result of step SA110 is "Yes." If a position designation operation has not been detected, the determination result of step SA110 is "No." If the determination result of step SA110 is "No," the processing device 160 executes the process of step SA110 again. That is, the process of step SA110 is repeatedly executed until a position designation operation is detected. If the determination result of step SA110 is "Yes," the processing device 160 executes the processes from step SA120 onward. In step SA120, the processing device 160 functions as a first recording unit 160b. In step SA120, the processing device 160 records the position information. More specifically, in step SA120, the processing device 160 first identifies the location of the terminal 10 in real space at the time the location specification operation was performed (i.e., the first time), i.e., the location of the first point, based on the location on the map specified by the measurer. The processing device 160 then associates location information representing the location in real space with date and time information indicating the first time in the first management table TBL1. For example, suppose the first time is 2:00 PM on July 27, 2023, and the latitude and longitude of the first point are "43.060219" and "141.352120." In this case, the processing device 160 associates the location information with the latitude of "43.060219" and the longitude of "141.352120" in the first management table TBL1 with the date and time information indicating 2:00 PM on July 27, 2023.

[0030] In step SA130 following step SA120, processing device 160 starts counting the number of steps. In step SA140 following step SA130, processing device 160 functions as second recording unit 160c. In step SA140, processing device 160 records identification information. More specifically, in step SA140, processing device 160 associates identification information indicating the base station 30 with which terminal 10 was communicating at that date and time in second management table TBL2, with date and time information indicating the time when step SA140 was executed.

[0031] In step SA150 following step SA140, the processing device 160 determines whether a unit time has elapsed since the most recent execution of step SA140. If the elapsed time since the most recent execution of step SA140 is less than the unit time, the determination result of step SA150 is "No." If the elapsed time since the most recent execution of step SA140 reaches the unit time, the determination result of step SA150 is "Yes." If the determination result of step SA150 is "Yes," the processing device 160 executes the processing of step SA140 described above again. If the determination result of step SA150 is "No," the processing device 160 executes the processing of step SA160.

[0032] In step SA160, the processing device 160 determines whether a position designation operation has been performed again on the input device 130. If a position designation operation has been performed again, the determination result of step SA160 is "Yes." If a position designation operation has not been performed again, the determination result of step SA160 is "No." If the determination result of step SA160 is "No," the processing device 160 executes the processing of step SA150 described above again. If the determination result of step SA160 is "Yes," the processing device 160 executes the processing of step SA170 and subsequent steps.

[0033] For example, if a location designation operation is not performed until 14:00:36 on July 27, 2023, the determination result of step SA160 will be No, and the processing of steps SA140 and SA150 will be repeatedly executed until 14:00:36 on July 27, 2023. Therefore, base station information is stored in the second management table TBL2 every time a unit time elapses from 14:00:36 on July 27, 2023, which is the first time point.

[0034] In step SA170, which is executed if the determination result of step SA160 is "Yes," the processing device 160 functions as a first recording unit 160b. In step SA170, the processing device 160 identifies the position of the terminal 10 in real space at the time when the position designation operation is performed again (i.e., the second time), i.e., the position of the second point, based on the position on the map designated by the measurer. Then, the processing device 160 associates position information representing the position in real space with date and time information indicating the second time, and stores them in the first management table TBL1. For example, if the position of terminal 10 is identified as having a latitude of "43.060" and a longitude of "141.352" at the time the position specification operation is performed again, the position information indicating the latitude of "43.060" and the longitude of "141.352" is stored in the first management table TBL1 in association with the date and time information indicating 14:00:36 on July 27, 2023.

[0035] In step SA180 following step SA170, the processing device 160 functions as a third recording unit 160d. In step SA160, the processing device 160 determines the number of steps taken by the person taking the step during the period from the first time to the second time based on the sensor information output from the sensor 140 during that period. The processing device 160 calculates the travel distance of the person taking the step during the period from the first time to the second time by multiplying the determined number of steps by the person's stride length. The processing device 160 then stores travel speed information D1 representing the average travel speed of the terminal 10 in the storage device 150. In step SA190 following step SA180, the processing device 160 determines whether an end operation instructing the end of execution of the program PR1 has been detected. If an end operation has been detected, the determination result of step SA190 is "Yes." If the determination result of step SA190 is "Yes," the processing device 160 terminates execution of this recording method. If the termination operation is not detected, the determination result of step SA190 is “No.” If the determination result of step SA190 is “No,” the processor 160 executes the processes from step SA140 onward again.

[0036] A-3: Configuration of Coverage Range Measurement Device 20 Fig. 7 is a diagram showing an example configuration of the coverage range measurement device 20. As shown in Fig. 7, the coverage range measurement device 20 includes a communication device 210, a display device 220, an input device 230, a storage device 250, a processing device 260, and a bus 270 that interconnects these devices.

[0037] The communication device 210, like the communication device 110, is connected to the communication network NW wirelessly or via a wired connection and communicates with other devices connected to the communication network NW. An example of this other device is the terminal 10. The communication device 210 may include a communication interface that performs wired communication with other devices via, for example, a USB (Universal Serial Bus) cable. In a configuration in which the communication device 210 includes the communication interface, the terminal 10 may be connected to the communication device 210 via a USB cable. The display device 220, like the display device 120, is a variety of display panels such as a liquid crystal display panel or an organic EL display panel. The display device 220 displays information to the outside under the control of the processing device 260. The input device 230, like the input device 130, is an input device that accepts input from the outside. Specifically, the input device 230 is a keyboard, a mouse, a switch, a button, or the like.

[0038] The storage device 250 is a recording medium that can be read by the processing device 260. Like the storage device 150, the storage device 250 includes a non-volatile memory and a volatile memory. The storage device 250 stores a program PR2, a third management table TBL3, a fourth management table TBL4, and a fifth management table TBL5. The third management table TBL3, the fourth management table TBL4, and the fifth management table TBL5 will be explained later.

[0039] The processing device 260 includes one or more central processing units (CPUs), similar to the processing device 160. The processing device 260 reads the program PR2 from the storage device 250. The processing device 260 executes the read program PR2, thereby functioning as an acquisition unit 260a, an interpolation unit 260b, a determination unit 260c, and a display control unit 260d.

[0040] The acquiring unit 260a acquires the first management table TBL1 (see FIG. 4 ), the second management table TBL2 (see FIG. 5 ), and the movement speed information D1 from the terminal 10 by communicating with the terminal 10 using the communication device 210. As described above, the first management table TBL1 stores date and time information indicating a first time, location information indicating a first location, and date and time information indicating a second time and location information indicating the second location. The second management table TBL2 stores identification information acquired for each unit time during the period from the first time to the second time, and date and time information indicating the date and time at which the identification information was acquired. In an aspect in which the first management table TBL1, the second management table TBL2, and the movement speed information D1 are stored in an SD card of the terminal 10, an interface for connecting the SD card may be provided in the coverage range measurement device 20. In a case where the interface is provided in the coverage range measuring device 20, the acquisition unit 260a acquires the first management table TBL1, the second management table TBL2, and the movement speed information D1 by reading data from an SD card connected to the interface.

[0041] The interpolation unit 260b generates a third management table TBL3 based on the movement speed information D1 and the first management table TBL1. FIG. 8 is a diagram showing an example of the third management table TBL3. The third management table TBL3 differs from the first management table TBL1 in that it includes estimated position information. The estimated position information indicates the estimated position of the terminal 10 at the date and time indicated by the date and time information stored in the second management table TBL2 (the date and time each unit time elapses from the first time). The estimated position information is obtained by interpolation based on the movement speed information D1. More specifically, the interpolation unit 260b outputs the estimated position information by interpolating the position of the terminal 10 on a line segment extending from the first location to the second location according to the average movement speed indicated by the movement speed information D1. More specifically, in this embodiment, the interpolation unit 260b outputs estimated position information (X(t), Y(t)) indicating the estimated position of the terminal 10 t seconds after the first time according to the following equations (1) and (2). In equations (1) and (2), X1 represents the latitude of the first point. Y1 represents the longitude of the first point. In equations (1) and (2), X2 represents the latitude of the second point. Y2 represents the longitude of the second point. In equations (1) and (2), v represents the moving speed of the terminal 10. L represents the distance between the first point and the second point. The interpolation unit 260b generates the third management table TBL3 by associating this estimated position information with date and time information representing the time t seconds after the first time and registering it in the first management table TBL1. The coefficient (X2-X1) / L of the second term on the right side of equation (1) is a correction coefficient used to correct the estimated position indicated by the estimated position information so that the estimated position is evenly distributed along the line segment from the first point to the second point when the distance between the first point and the second point does not match the moving distance of the terminal 10. The same applies to the coefficient (Y2-Y1) / L of the second term on the right side of equation (2).

[0042] The determination unit 260c determines a fifth management table TBL5, which indicates the coverage areas of base stations with which the terminal 10 communicated during the period from the first time to the second time, based on the contents stored in the second management table TBL2 and the third management table TBL3. More specifically, the determination unit 260c generates a fourth management table TBL4 shown in FIG. 9 by merging the contents stored in the second management table TBL2 and the contents stored in the third management table TBL3 using date and time information as a key. As shown in FIG. 9, the fourth management table TBL4 stores location information and identification information in association with date and time information. Merging the contents stored in the second management table TBL2 and the contents stored in the third management table TBL3 using date and time information as a key means associating identification information and location information associated with date and time information indicating the same date and time into a single record. Each record stored in the fourth management table TBL4 indicates that the position occupied by the terminal 10 in real space at the date and time indicated by the date and time information contained in the record is the position indicated by the location information contained in the record, and that the terminal 10 was communicating with the base station 30 indicated by the identification information contained in the record.

[0043] Next, the determination unit 260c generates a fifth management table TBL5 representing the coverage area of ​​each base station 30 based on the contents stored in the fourth management table TBL4. FIG. 10 is a diagram showing an example of the contents stored in the fifth management table TBL5. As shown in FIG. 10, the fifth management table TBL5 stores, in association with identification information, coverage area information (MBR1, MBR2, and MB3 in the example shown in FIG. 10) indicating the coverage area of ​​the base station 30 indicated by the identification information. This coverage area information is generated as follows. The determination unit 260c first references the fourth management table TBL4 and extracts location information for each piece of identification information. Then, the determination unit 260c determines the smallest shape (in this embodiment, the smallest rectangle, but it may also be the smallest circle) that encompasses each position indicated by the multiple pieces of location information extracted for the base station 30 as the coverage area of ​​the base station 30. For example, when the location information indicating the positions P1 and P5 shown in FIG. 11 and the estimated location information indicating the positions P2, P3, and P4 for the base station 30(1) are extracted from the fourth management table TBL4, the determination unit 260c determines the coverage area CA1 of the base station 30(1) as shown in FIG. 11.

[0044] The display control unit 260d displays on the display device 220 an image of the coverage area of ​​each base station 30 determined by the determination unit 260c, superimposed on an image of a map of the area that was the subject of a field survey using the terminal 10. Fig. 12 shows an example in which an image G3 representing the coverage area CA1 of the base station 30(1) determined by the determination unit 260c is displayed superimposed on an image G2 of the map of the target area. The image G2 of the map of the target area is an example of the second image. The image G3 representing the coverage area CA1 is an example of the first image.

[0045] Furthermore, the processing device 260 operating in accordance with the program PR2 executes a coverage measurement method embodying the features of the present disclosure. Figure 13 is a flowchart showing the process flow of this coverage measurement method. As shown in Figure 13, this coverage measurement method includes the processes of steps SB110 to SB140.

[0046] In step SB110, the processing device 260 functions as an acquisition unit 260a. In step SB110, the processing device 260 communicates with the terminal 10 using the communication device 210 to acquire the first management table TBL1 (see FIG. 4), the second management table TBL2 (see FIG. 5), and the movement speed information D1 from the terminal 10.

[0047] In step SB120, the processing device 260 functions as an interpolation unit 260b. In step SB120, the processing device 260 generates a third management table TBL3 based on the average movement speed of the terminal 10 indicated by the movement speed information D1 and the first management table TBL1. More specifically, the processing device 260 generates the third management table TBL3 by additionally registering in the first management table TBL1 date and time information indicating the date and time after t seconds have elapsed since the first time and the estimated position information of the terminal 10 at that date and time in association with each other.

[0048] In step SB130, the processing device 260 functions as a determination unit 260c. In step SB130, the processing device 260 generates a fourth management table TBL4 by merging the contents stored in the second management table TBL2 and the contents stored in the third management table TBL3 using date and time information as a key. Then, the processing device 260 generates a fifth management table TBL5 that represents the coverage area of ​​each base station 30 based on the contents stored in the fourth management table TBL4.

[0049] In step SB140, the processing device 260 functions as the display control unit 260d. In step SB140, the processing device 260 displays on the display device 220 an image of the coverage area of ​​each base station 30 determined by the determination unit 260c, superimposed on the image of the map of the target area.

[0050] According to this embodiment, the position of the terminal 10 can be interpolated with high accuracy by taking into account the walking speed of the person carrying the terminal 10 and conducting the field survey. The coverage range measurement device 20 can accurately measure the coverage range of the base station 30 through interpolation. According to this embodiment, the person conducting the survey does not need to frequently perform the operation of specifying the position, reducing the burden on the person conducting the survey.

[0051] B. Modifications The above-described embodiment may be modified as follows. Furthermore, the embodiment and each modification may be combined as appropriate. (1) Modification 1 In the above-described embodiment, an acceleration sensor is exemplified as the sensor 140, but the present disclosure is not limited to this. The terminal 10 may be equipped with one or more sensors 140. The one or more sensors 140 may be an acceleration sensor and a gyro sensor. The one or more sensors may be an acceleration sensor and a geomagnetic sensor. The one or more sensors may be an acceleration sensor, a gyro sensor, and a geomagnetic sensor.

[0052] (2) Modification 2 Instead of the movement speed information D1, sensor information output from the sensor 140 during the period from the first time to the second time may be transmitted from the terminal 10 to the coverage range measurement device 20. In this case, the interpolation unit 260b may calculate the movement speed along each of two directions perpendicular to the vertical direction based on the acceleration of three axes represented by the sensor information. Furthermore, in an aspect in which the sensor information is transmitted from the terminal 10 to the coverage range measurement device 20, the interpolation unit 260b may determine the movement direction of the terminal 10 in addition to the movement speed of the terminal 10 based on the sensor information. The movement direction may be determined based on sensor information from a geomagnetic sensor and sensor information from a gyro sensor. The movement direction may be determined based on sensor information from a geomagnetic sensor and sensor information from an acceleration sensor.

[0053] In an aspect in which the moving direction is identified in addition to the moving speed, for example, the first time is t1, the second time is t2, the unit time is Δt, and M is an arbitrary integer equal to or greater than 2. In this case, assume that there is a relationship of t1 + M × Δt ≦ t2 < t1 + (M + 1) × Δt. The position (X(t), Y(t)) of the terminal 10 at time t, which is k (k is an integer equal to or greater than 1 and less than M) × Δt after the first time t1, can be estimated more accurately than in the above embodiment by using the following equations (3) and (4) instead of the above equations (1) and (2). Note that U(j) in equation (3) is the moving speed in the latitudinal direction of the terminal 10 at the time j (an integer equal to or greater than 0 and less than k) × Δt after the first time t1. U(0) is the moving speed in the latitudinal direction of the terminal 10 at the time j (an integer equal to or greater than 0 and less than k) × Δt after the first time t1. In equation (4), V(j) is the moving speed of the terminal 10 in the longitude direction at the time j×Δt has elapsed since the first time t1. V(0) is the moving speed of the terminal 10 in the longitude direction at the first time t1. According to this aspect, the position of the terminal 10 is estimated taking into account the moving direction of the terminal 10 in addition to the moving speed of the terminal 10. Therefore, when the moving distance of the terminal 10 differs from the distance between the first point and the second point, for example, when the terminal 10 moves in a zigzag pattern relative to the line segment connecting the first point and the second point, the position of the terminal 10 can be estimated more accurately than in the above embodiment. Furthermore, various types of sensor information may be stored in the second management table TBL2. In this case, the acquiring unit 260a acquires the second management table TBL2 from the terminal 10, and therefore, can acquire one or more pieces of sensor information from the terminal 10 at once.

[0054] (3) Modification 3 The processing device 160 may execute a recording method whose processing flow is shown in the flowchart of FIG. 14A instead of the recording method shown in the flowchart of FIG. 6. In FIG. 14A, the same processes as those in FIG. 6 are assigned the same reference numerals. As is clear from comparing FIG. 14A with FIG. 6, the recording method of this modification differs from the recording method of the above embodiment in that the processing of step SA155 is executed if the determination result of step SA150 is "No." In step SA155, the processing device 160 determines whether the identification information of the base station with which the communication device 110 communicates is different from the identification information most recently stored in the second management table TBL2. In other words, in step SA155, the processing device 160 determines whether the base station 30 with which the communication device 110 is communicating has changed from the base station 30 with which the communication device 110 communicated when the identification information was most recently stored in the second management table TBL2. If the determination result of step SA155 is "No", the processing device 160 executes the process of step SA160. Conversely, if the determination result of step SA155 is "Yes", the processing device 160 executes the process of step SA140. Therefore, according to this aspect, when the base station with which the communication device 110 is communicating changes, the identification information of the base station after the change is stored in the second management table TBL2 in association with date and time information indicating the reference time, which is the time when the change was detected. The base station with which the terminal 10 communicated before the reference time is, for example, the first base station. The base station with which the terminal 10 communicated after the reference time is, for example, the second base station.

[0055] As described above, the interpolation unit 260b outputs estimated location information indicating the estimated location of the terminal 10 at the date and time indicated by the date and time information stored in the second management table TBL2. The second management table TBL2 in this embodiment stores records including date and time information indicating a reference time. Therefore, according to this embodiment, the interpolation unit 260b outputs estimated location information at the reference time. The location indicated by the estimated location information at the reference time corresponds to the boundary between the coverage area of ​​the first base station and the coverage area of ​​the second base station. Therefore, according to this embodiment, the boundary between the coverage area of ​​the first base station and the coverage area of ​​the second base station can be measured with high accuracy.

[0056] The interpolation unit 260b may estimate estimated location information indicating the location of the terminal 10 between the first time and the reference time based on the first location and the estimated location information at the reference time. Specifically, the interpolation unit 260b may calculate estimated location information indicating the location of the terminal 10 between the first time and the reference time (the location t seconds after the first time) by using the latitude and longitude of the first location for (X1, Y1) in the above-mentioned equations (1) and (2) and the latitude and longitude at the reference time for (X2, Y2). Similarly, the interpolation unit 260b may estimate estimated location information indicating the location of the terminal 10 between the second time and the reference time based on the second location and the estimated location information at the reference time. Specifically, the interpolation unit 260b uses the latitude and longitude of the second point for (X2, Y2) in the above-mentioned equations (1) and (2), and the latitude and longitude at the reference time for (X1, Y1) to calculate estimated location information indicating the position of the terminal 10 between the first time and the reference time (the position t seconds after the reference time).

[0057] For example, as shown in FIG. 14B , assume that the terminal 10 is located at position Pr1 at the first time t1, and has moved to position Pr2 at the second time t2. As shown in FIG. 14B , during the period from the first time t1 to the reference time tref, the terminal 10 communicates with a base station having identification information ID1. During the period from the first time t1 to the reference time tref, the terminal 10 stores the identification information "ID1" in association with date and time information in the second management table TBL2 every time a unit time Δt elapses from the first time t1. At the reference time tref, a change in the base station 30 occurs, so the determination result of step SA155 described above becomes "Yes," and the processing of step SA140 is executed. As a result, the date and time information indicating the reference time tref is stored in association with the identification information "ID2" in the second management table TBL2. During the period from the reference time tref to the second time t2, the terminal 10 communicates with the base station with identification information ID2. Therefore, every time a unit time Δt elapses from the reference time tref, the identification information "ID2" is associated with date and time information and stored in the second management table TBL2. Estimated position information indicating the estimated position Pp4 at the reference time tref is calculated based on the latitude and longitude of the first point, the latitude and longitude of the second point, and the average movement speed according to the above-mentioned formulas (1) and (2). The interpolation unit 260b estimates an estimated position Pp1 at time t1+Δt, an estimated position Pp2 at time t1+2×Δt, and an estimated position Pp3 at time t+3×Δt based on the position Pr1 and the estimated position Pp4. Note that Δt is a unit time. Furthermore, the interpolation unit 260b estimates an estimated position Pp5 at time tref+Δt, an estimated position Pp6 at time tref+2×Δt, and an estimated position Pp7 at time tref+3×Δt based on the estimated position Pp4 and the position Pr2.

[0058] The estimated position Pp4 at the reference time tref is estimated based on Pr1 and Pr2, which are position information on the map. Meanwhile, the estimated positions Pp1, Pp2, and Pp3 are estimated based on Pr1, which is position information on the map, and the estimated position Pp4. Furthermore, the estimated positions Pp5, Pp6, and Pp7 are estimated based on Pr1, which is position information on the map, and the estimated position Pp4. Since the estimated position Pp4 at the reference time tref is estimated based on two pieces of position information on the map, the estimation accuracy is higher than that of the estimated positions Pp1, Pp2, Pp3, Pp5, Pp6, and Pp7. The position of the terminal 10 at the reference time tref, when the base station 30 is switched, is important information for determining the coverage area. According to this modification, the accuracy of the coverage area can be improved.

[0059] (4) Variation 4 If an underground mall exists in the target area of ​​the field survey, the acquisition unit 260a may acquire map information representing a map of the underground mall. In this case, it is preferable that the map represented by the map information has the same scale as the map of the target area. The determination unit 260c may determine, as the coverage area of ​​the base station 30 in the underground mall, a portion of the coverage area of ​​the base station 30 determined for each piece of identification information that overlaps with the map of the underground mall. Similarly, if a high-rise building exists in the target area of ​​the field survey, the acquisition unit 260a may acquire map information representing a map of the high-rise building. The determination unit 260c may determine, as the coverage area of ​​the base station 30 in the high-rise building, a portion of the coverage area of ​​the base station 30 determined for each piece of identification information that overlaps with the map of the high-rise building. For example, as shown in FIG. 15, assume that an underground mall UC exists in the target area. Furthermore, as shown in FIG. 15, assume that a portion A1 of the coverage area CA1 of the base station 30(1) determined by the determination unit 260c overlaps with the map of the underground mall UC. In this case, the determination unit 260c determines the area A1 as the coverage area of ​​the base station 30(1) in the underground mall UC. Furthermore, when the coverage area of ​​the base station 30 in the underground mall is determined for each base station 30 by the determination unit 260c, the display control unit 260d may display, on the display device 220, an image GT obtained by superimposing an image GA, which is a third image representing the coverage area of ​​the base station 30(1) in the underground mall UC, on an image GC, which is a fourth image representing a map of the underground mall, as shown in FIG.

[0060] (5) Modification 5 When the one or more sensors include a gyro sensor, the processing device 160 of the terminal 10 may function as a determination unit 160f and a display control unit 160g as shown in FIG. 17 . The determination unit 160f determines that the movement direction of the terminal 10 has changed by a first angle or more based on sensor information from the gyro sensor. If the determination result of the determination unit 160f is positive, the display control unit 160g may display an image on the display device 120 of the terminal 10 prompting the user to perform a position specification operation. The first angle is, for example, 45 degrees, preferably 60 degrees or 90 degrees. For example, as shown in FIG. 18 , when the movement direction of the terminal 10 changes by 90 degrees, the current location may be flashed to prompt the user to perform a position specification operation. In FIG. 18 , the movement trajectory of the terminal 10 is indicated by an arrow Y. The tip of the arrow Y in FIG. 18 corresponds to the current location of the terminal 10.

[0061] C: Others (1) In the above-described embodiment, ROM and RAM are given as examples of storage devices 150 and 250, but storage devices 150 and 250 may also be flexible disks, magneto-optical disks (e.g., compact disks, digital versatile disks, Blu-ray (registered trademark) disks), smart cards, flash memory devices (e.g., cards, sticks, key drives), CD-ROMs (Compact Disc-ROMs), registers, removable disks, hard disks, floppy (registered trademark) disks, magnetic strips, databases, servers, or other suitable storage media.

[0062] (2) In the above-described embodiments, the described information, signals, etc. may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0063] (3) In the above-described embodiment, input and output information may be stored in a specific location (for example, a memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be transmitted to another device.

[0064] (4) In the above-described embodiment, the determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a comparison of numerical values ​​(e.g., a comparison with a predetermined value).

[0065] (5) The order of the process procedures, sequences, flowcharts, etc. illustrated in the above-described embodiments may be rearranged unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0066] (6) Each function illustrated in Figures 2 and 7 is realized by any combination of hardware and / or software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (e.g., wired, wireless, etc.) and these multiple devices. A functional block may be realized by combining software with the single device or the multiple devices.

[0067] (7) The programs exemplified in the above-described embodiments should be broadly construed to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., regardless of whether they are called software, firmware, middleware, microcode, hardware description language, or by other names.

[0068] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0069] (8) In each of the foregoing embodiments, the terms "system" and "network" are used interchangeably.

[0070] (9) The information, parameters, etc. described in this disclosure may be expressed using absolute values, relative values ​​from a predetermined value, or corresponding other information.

[0071] (10) In the above-described embodiments, the portable device may be a mobile station (MS). Those skilled in the art may also refer to a mobile station as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other appropriate terminology. In this disclosure, the terms "mobile station," "user terminal," "user equipment (UE)," "terminal," etc. may be used interchangeably.

[0072] (11) In the above-described embodiments, the terms "connected," "coupled," or any variation thereof refers to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using at least one of one or more wires, cables, and printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0073] (12) In the above embodiments, the phrase "based on" does not mean "based only on," unless otherwise specified. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0074] (13) As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining something as "determining" or "determining," and the like. Furthermore, "judgment" and "decision" may include regarding receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, and accessing (e.g., accessing data in memory) as having been "judgment" or "decision." Furthermore, "judgment" and "decision" may include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judgment" or "decision." In other words, "judgment" and "decision" may include regarding some action as having been "judgment" or "decision." Furthermore, "judgment" may be interpreted as "assuming," "expecting," "considering," etc.

[0075] (14) In the above embodiments, when "include," "including," and variations thereof are used, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, the term "or," as used in this disclosure, is not intended to be an exclusive or.

[0076] (15) In this disclosure, when articles are added by translation, such as a, an, and the in English, the disclosure may include the noun following these articles being plural.

[0077] (16) In this disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "combined" may also be interpreted in the same way as "different."

[0078] (17) The aspects / embodiments described in this disclosure may be used alone, in combination, or switched depending on the implementation. Notification of predetermined information (e.g., notification that "X is true") is not limited to being explicit, but may be implicit (e.g., not notifying the predetermined information).

[0079] 1...communication system, 10...terminal, 20...coverage range measurement device, 110, 210...communication device, 120, 220...display device, 130, 230...input device, 140...sensor, 150, 250...storage device, 160, 260...processing device, 110a, 160g, 260d...display control unit, 160b...first recording unit, 160c...second recording unit, 160d...third recording unit, 160e...transmitting unit, 160f...determination unit, 260b...interpolation unit, 260c...determination unit, PR1, PR2...program, TBL1...first management table, TBL2...second management table, TBL3...third management table, TBL4...fourth management table, TBL5...fifth management table, D1...movement speed information.

Claims

1. A base station coverage range measurement device comprising: first location information indicating the location of a first point where a person carrying a terminal that communicates with multiple base stations is located at a first time; second location information indicating the location of a second point where the person is located at a second time; an acquisition unit that acquires one or more pieces of sensor information output from one or more sensors of the terminal during a period from the first time to the second time; an interpolation unit that outputs estimated location information that estimates the location of the terminal by interpolating the location of the terminal during the period based on the one or more pieces of sensor information; and a determination unit that determines the coverage range of base stations with which the terminal communicated during the period based on the estimated location information.

2. The base station coverage range measuring device according to claim 1, wherein the acquisition unit acquires, during the period, at least one pair of identification information indicating a base station with which communication was made among the plurality of base stations and the time of communication; the interpolation unit estimates the estimated location information by interpolating the position of the measurer during the period based on the at least one pair of identification information and time in accordance with the moving speed and moving direction of the terminal obtained from the one or more pieces of sensor information; and the determination unit determines the coverage range of the base station for each piece of identification information based on the estimated location information.

3. The base station coverage range measuring device according to claim 2, wherein the plurality of base stations include a first base station and a second base station, and the interpolation unit estimates the estimated location information at a reference time that is at least the time when the base station indicated by the identification information changes from the first base station to the second base station.

4. The base station coverage range measuring device of claim 3, wherein the acquisition unit acquires the first time and the second time, and the interpolation unit estimates the estimated location information indicating the location of the terminal between the first time and the reference time based on the first location and the estimated location information at the reference time, and estimates the estimated location information indicating the location of the terminal between the second time and the reference time based on the second location and the estimated location information at the reference time.

5. The base station coverage range measuring device according to claim 2, wherein, if an underground mall exists in the area, the determination unit determines the portion of the base station coverage range determined for each of the identification information that overlaps with a map of the underground mall as the base station coverage range in the underground mall, and if a high-rise building exists in the area, the portion of the base station coverage range determined for each of the identification information that overlaps with a map of the high-rise building as the base station coverage range in the high-rise building.

6. The base station coverage range measuring device of claim 1, further comprising a display control unit that displays on a display device a first image representing the coverage range determined by the determination unit for each of the identification information, superimposed on a second image representing a map of the area including the plurality of base stations.

7. A terminal comprising: a communication device that communicates with a plurality of base stations; one or more sensors; a first recording unit that records first date and time information indicating a first time in association with first location information indicating a location of a first point where a measurer is located at the first time, and records second date and time information indicating the second time in association with second location information indicating a location of a second point where the measurer is located at the second time; a second recording unit that records at least one pair of identification information indicating a base station with which the measurer communicated using the communication device among the plurality of base stations during a period from the first time to the second time, and third date and time information indicating the time of communication; and a transmission unit that transmits the pair of the first location information and the first date and time information, the pair of the second location information and the second date and time information, at least one pair of the identification information and the third date and time information, and one or more pieces of sensor information output from the one or more sensors during the period from the first time to the second time, to a coverage range measurement device that measures the coverage range of each of the plurality of base stations.

8. A method for measuring the coverage area of ​​a base station, comprising: acquiring first location information indicating the location of a first point where a person carrying a terminal that communicates with multiple base stations is located at a first time; second location information indicating the location of a second point where the person is located at a second time; and one or more pieces of sensor information output from one or more sensors of the terminal during a period from the first time to the second time; outputting estimated location information that estimates the location of the terminal by interpolating the location of the terminal during the period based on the sensor information; and determining the coverage area of ​​base stations with which the terminal communicated during the period based on the estimated location information.

Images