JP2013124885A - Positioning device, positioning method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology for accurately performing positioning and indicating accuracy of positioning.SOLUTION: A positioning device performs positioning based on a radio marker received from a radio station. In the positioning device, a radio marker is received from a radio station, a distance to the radio station is determined based on the received radio marker and a position where the device is located is calculated by performing positioning based on the distance to the radio station and a position of the radio station. While referring to an arrangement table indicating positions of a plurality of radio stations, a radio station within a predetermined range from the position are extracted as a proximate station and the distance to the radio station from which the radio marker has been received is compared with a distance to the proximate station. It is determined whether positioning accuracy is made higher than that of positioning for the position where the device is located in the case where positioning is performed by using a radio marker from the proximate station and if it is determined that the positioning accuracy is made higher, the position where the device is located is calculated again based on the radio marker received from the proximate station.

Description

  This case relates to a technique for acquiring position information.

  2. Description of the Related Art In recent years, services have been provided that acquire user location information using GPS (Global Positioning System), perform map search, navigation, and provide peripheral information.

  However, positioning by GPS has been difficult to use indoors, underground malls, and valleys of buildings due to the fact that radio signals from satellites do not reach or reflect.

As a positioning technique that can be used even indoors, wireless LAN (Local Area) is available.
a Wireless communication device capable of communicating with a network base station (access point) communicates with the surrounding base stations, and the signal strength of the radio signal received from the base station and the location information of the base station registered in advance A technique for estimating the position of a wireless communication device based on the above is known.

JP 2005-286811 A JP 2009-65604 A JP 2007-43574 A

  As described above, when positioning is performed using the signal strengths of the radio signals received from the base stations, the positioning accuracy can be increased as the variance of the signal strengths of the radio signals received from the plurality of base stations is increased. That is, it is desirable to perform positioning based on a plurality of radio signals including a strong radio signal from a close base station and a weak radio signal from a distant base station, but it is not always possible to receive radio signals that are appropriately distributed. .

  For example, there may be a case where a radio signal cannot be received from a nearby base station due to packet loss, the presence of a shield, interference with other communications, etc. even if a nearby radio base station exists. For this reason, sufficient accuracy may not be obtained.

  Therefore, the disclosed system aims to provide a technique for performing positioning with high accuracy.

In order to solve the above problems, the positioning device of the present invention is
A positioning device that performs positioning based on a radio sign received from a radio station,
A receiver for receiving a radio beacon from a radio station;
Obtaining the distance to the wireless station based on the received radio indicator, positioning based on the distance to the wireless station and the position of the wireless station, a positioning unit for obtaining the location,
An extraction unit that refers to an arrangement table indicating positions of a plurality of wireless stations, and extracts wireless stations that are within a predetermined range from the positions as neighboring stations;
Whether the positioning accuracy is higher than the positioning of the location when the distance from the wireless station that has received the wireless mark is compared with the distance from the adjacent station and positioning is performed using the wireless mark from the adjacent station An accuracy determination unit for determining whether or not
A repositioning control unit that, when it is determined that the positioning accuracy is increased, causes the positioning unit to obtain a location again based on a radio signal received from the neighboring station.

  The positioning device may include an output control unit that outputs information indicating the positioning accuracy obtained by the accuracy determining unit together with the location information as a positioning result.

  The positioning device may indicate the positioning accuracy by a predetermined number of marks, an icon state change, or a circle centered on the location.

  The positioning device may include an output control unit that outputs the location as a positioning result when the accuracy determination unit determines that the positioning accuracy does not increase.

A positioning device is a method for positioning based on a radio beacon received from a radio station,
Receiving a radio beacon from the radio station;
Obtaining a distance from the wireless station based on the received wireless sign, performing positioning based on the distance to the wireless station and the position of the wireless station, and obtaining a location position;
Referring to an arrangement table showing positions of a plurality of radio stations, and extracting a radio station within a predetermined range from the location as a proximity station;
When comparing the distance from the radio station that has received the radio beacon to the location and the distance from the proximity station to the location, and positioning using the radio beacon from the proximity station, the location of the location Determining whether positioning accuracy is higher than positioning; and
When it is determined that the positioning accuracy is increased, the step of determining the location again based on the radio signal received from the proximity station;
Positioning method to perform.

  In the positioning method, information indicating the positioning accuracy may be output together with the location information as a positioning result.

  In the positioning method, the positioning accuracy may be indicated by a predetermined number of marks, an icon state change, or a circle centered on the location.

  The positioning method may output the location as a positioning result when it is determined that the positioning accuracy does not increase.

  Further, the present invention may be a program for causing a computer to execute the positioning method. Furthermore, the program may be recorded on a computer-readable recording medium.

  Here, the computer-readable recording medium refers to a recording medium that accumulates information such as data and programs by electrical, magnetic, optical, mechanical, or chemical action and can be read from the computer. . Examples of such a recording medium that can be removed from the computer include a flexible disk, a magneto-optical disk, a CD-ROM, a CD-R / W, a DVD, a DAT, an 8 mm tape, and a memory card.

  Further, there are a hard disk, a ROM (read only memory), and the like as a recording medium fixed to the computer.

  The disclosed system can provide a technique for performing positioning with high accuracy. Moreover, the accuracy of positioning can be shown.

Schematic diagram of location information providing system according to the present invention Diagram showing the hardware configuration of the location information server Functional block diagram showing the configuration of the location information server The figure which shows the structural example of an arrangement | positioning table Illustration of positioning method The figure which shows the example of arrangement of a radio station Illustration of positioning process The figure which shows the arrangement of the radio station when conducting the experiment which asks for the relation between the dispersion of the radio wave intensity and the positioning accuracy Figure showing measurement results Diagram showing the correspondence between dispersion value and positioning error Graph showing changes in positioning error due to differences in dispersion A graph showing changes in positioning error due to differences in dispersion when there are two radio beacons (samples) received from each radio station A graph showing changes in positioning error due to differences in dispersion when there are three radio signs (samples) received from each radio station The figure which illustrates the evaluation table for calculating | requiring the evaluation value of positioning accuracy Figure showing an example of positioning result output Explanatory drawing which shows the positioning method of a modification

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The configuration of the following embodiment is an exemplification, and the present invention is not limited to the configuration of the embodiment.

(1) Outline of Positioning Device FIG. 1 is a schematic diagram of a positioning system 10 according to the present invention.

  The positioning system 10 includes a plurality of wireless stations 1 that transmit wireless signals and a user terminal (positioning device) 2 that performs positioning using the wireless signals.

  The wireless station 1 is a device that transmits a wireless signal from a predetermined position such as a mobile phone base station, a wireless LAN access point, a beacon module that transmits a beacon frame, for example, a place sticker (registered trademark).

  The positioning system 10 of this example can be used in an area where a plurality of radio stations 1 are installed, and in particular, the radio station 1 can be installed even in places where GPS signals cannot be obtained, such as shopping malls and underground malls. Positioning is possible with.

  The location information of each radio station 1 is made into a database, and the user terminal 2 obtains the distance to each radio station 1 based on radio signals received from the plurality of radio stations 1, and determines the location of each radio station 1 and each radio station. Based on the distance from the station 1, the current position is obtained.

(2) Hardware Configuration of User Terminal (Positioning Device) FIG. 2 is a diagram illustrating a hardware configuration of the user terminal 2. The user terminal 2 includes a CPU (Central Processing Unit) 201 and a ROM (Read On
ly Memory) 202 and RAM (Random Access Memory) 2
03, host bus 204, bridge 205, external bus 206, interface 207, input device 208, output device 210, storage device (SSD) 211, storage medium read / write device 212, and communication device 215. And an information processing apparatus (computer) including an acceleration sensor 216.

  The CPU 201 functions as an arithmetic processing device and a control device, and controls the overall operation in the user terminal 2 according to various programs. Further, the CPU 201 may be a microprocessor. The ROM 202 stores programs used by the CPU 201, calculation parameters, and the like. The RAM 203 primarily stores programs used in the execution of the CPU 201, parameters that change as appropriate during the execution, and the like. These are connected to each other by a host bus 204 including a CPU bus.

The host bus 204 is connected to the PCI (Peripheral Co) via the bridge 205.
connected to an external bus 206 such as a component interconnect / interface bus. Note that the host bus 204, the bridge 205, and the external bus 206 are not necessarily configured separately, and these functions may be mounted on one bus.

  The input device 208 is, for example, an input means for a user to input information, such as a mouse, keyboard, touch panel, button, microphone, switch, and lever, and an input that generates an input signal based on the input by the user and outputs the input signal to the CPU 201 It consists of a control circuit. The user of the user terminal 2 can input various data and instruct processing operations to the user terminal 2 by operating the input device 208.

  The output device 210 includes, for example, a display device such as a liquid crystal display (LCD) device, an EL (electroluminescence) display, and an LED, and an audio output device such as a speaker and headphones. The output device 210 outputs the processing result of the CPU 201, for example. Specifically, various information such as input data and system operating status is displayed on a display device as text or images. On the other hand, the audio output device outputs messages, warning sounds, audio data of contents, and the like as sounds.

  The storage device 211 is a data storage device (auxiliary storage device) configured as an example of a storage unit of the user terminal 2 according to the present embodiment, and includes a storage medium, a recording device that records data in the storage medium, and a storage medium A reading device that reads data from the storage device, a deletion device that deletes data recorded in the storage medium, and the like. The storage device 211 is configured by, for example, an SSD (Solid State Drive). The storage device 211 drives a semiconductor memory and stores programs executed by the CPU 201 and various data. The storage device 211 also stores a location information database, which will be described later.

  The read / write device 212 is a reader / writer for a storage medium, and is built in or externally attached to the information processing server 2. The read / write device 212 reads information recorded on the mounted removable storage medium 24 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, and outputs the information to the RAM 203.

  The communication device 215 is a communication interface configured with, for example, a communication device for connecting to the communication network 12. The communication device 215 may be a wireless LAN (Local Area Network) compatible communication device, a wireless USB compatible communication device, or a Bluetooth (registered trademark) compatible communication device. . The communication device 215 according to the present embodiment is an example of a receiving unit that receives a radio marker from a radio station (neighboring station).

The acceleration sensor 216 is a sensor that detects acceleration and inputs it to the CPU 201 in order to detect the movement state of the user terminal 2. In addition, as long as acceleration can be detected, detection methods such as a mechanical method, an optical method, and a semiconductor method are not limited, but a semiconductor method is preferable because of ease of mounting and maintenance. For example, a capacitance type, a piezo resistance type, a gas temperature distribution type, or the like may be used.

(3) Function of User Terminal (Positioning Device) According to this Embodiment FIG. 3 is a functional block diagram of the user terminal 2 according to this embodiment. The user terminal 2 includes a positioning unit 231, an extraction unit 232, an accuracy determination unit 233, a re-positioning control unit 234, and an output control unit 235. The functions of the positioning unit 231, the extraction unit 232, the accuracy determination unit 233, the re-positioning control unit 234, and the output control unit 235 are mainly performed by the CPU 201 in accordance with a program, and each unit such as the communication device 215 and the storage device 211. It is realized by controlling.

  The first positioning unit 231 obtains the distance to the wireless station based on the received wireless sign, performs positioning based on the distance to the wireless station and the position of the wireless station, and obtains the location.

  The extraction unit 232 refers to an arrangement table indicating the positions of a plurality of wireless stations, and extracts wireless stations that are within a predetermined range from the positions as adjacent stations.

  The accuracy determination unit 233 compares the distance between the radio station that has received the radio beacon and the distance to the adjacent station, and when positioning is performed using the radio beacon from the adjacent station, the positioning accuracy is higher than the positioning at the location. Determine whether it increases.

  When the accuracy determination unit 233 determines that the positioning accuracy is increased, the re-positioning control unit 234 causes the positioning unit to obtain the location again based on the radio beacon received from the adjacent station.

  When the accuracy determination unit 233 determines that the positioning accuracy does not increase, the output control unit 235 outputs the location as a positioning result.

(4) Arrangement Table FIG. 4 is a diagram showing a configuration example of the arrangement table. As shown in FIG. 4, the arrangement table stores the location information of each radio station and the identification information of each radio station in association with each other.

  Here, the position information of each wireless station is, for example, latitude and longitude, coordinates on a specific map, and the like. In addition, when showing the position in facilities, such as a shopping mall, not only the position of a horizontal direction (horizontal direction) but the information of the position of a vertical direction (vertical direction) may be included.

  In the example of FIG. 4, identification information of a wireless station, information on a map file storage location, and position information (information indicating coordinates as a horizontal position and a floor as a vertical position) are recorded in association with each other.

(5) Positioning Method FIG. 5 is an explanatory diagram of a positioning method executed by the positioning device 2 in the positioning system 10.

  First, the communication device 215 receives a wireless sign from the wireless station 1 (S10). The wireless beacon in this example is a beacon frame from an access point of a wireless LAN, and the SSID included in the beacon frame is identification information that uniquely identifies the access point.

Next, the positioning unit 231 obtains the distance to the wireless station based on the received wireless sign, performs positioning based on the distance to the wireless station and the position of the wireless station, and the location position (positioning device 2 Is determined) (S20). The information on the position of the radio base station may be known or may be estimated from the received radio beacon. In the present embodiment, the position of the wireless station is acquired from the arrangement table of FIG. However, the present invention is not limited to this, and the configuration may be such that position information is received from a wireless station together with a wireless sign. Details of the positioning process will be described later.

  The extracting unit 232 refers to an arrangement table (FIG. 4) indicating the positions of a plurality of radio stations, and extracts radio stations that are within a predetermined range from the location obtained in step S20 as neighboring stations (S30).

  FIG. 6 is a diagram illustrating an arrangement example of radio stations. If, for example, radio signs from the radio stations 1-1, 1-2, and 1-9 are received in step S10, the center of gravity with the radio field intensity of these radio signs as a weight can be obtained as the location 91 in step S20. . Note that the location 91 may be obtained by other methods. In particular, in the first positioning for obtaining a proximity station, the current position (location) may be obtained by some simple method. A radio station located within a circle in the case where a circle RS is drawn around a predetermined range from the location position 91, for example, the location position 91 as a center with an appropriate distance from the location position 91 as a radius is extracted as a proximity station. Here, as the appropriate distance, the distance from the location 91 to the nearest radio station 1-9 can be used. In the example of FIG. 6, adjacent stations 1-3 and 1-5 are extracted.

  The accuracy determination unit 234 compares the distance between the radio station that has received the radio beacon and the distance to the adjacent station, and when positioning is performed using the radio beacon from the adjacent station, It is determined whether or not the positioning accuracy is increased (S40). For example, if a neighboring station closer to at least one of the radio stations 1-1, 1-2, and 1-9 that received the radio beacon in step S10 is extracted in step S30, it is determined that the positioning accuracy is improved, It is determined that the positioning system does not rise when the adjacent station is not extracted. Note that the determination of whether or not the positioning accuracy is improved may take into account the dispersion of the positions of the radio station and the neighboring stations. For example, in FIG. 6, in the case of the location 91, the positioning is not performed only by the radio stations 1-2, 1-3, and 1-9.

  When it is determined that the positioning accuracy is improved based on the determination result of step S40, the re-positioning control unit 234 returns to step S10, and again determines the positioning unit 231 based on the radio beacon received from the neighboring station. The location is obtained (S50).

  Next, when the accuracy determination unit 234 determines that the positioning accuracy does not increase, the output control unit 235 moves the process to step S60, and causes the accuracy determination unit 234 to evaluate the measurement accuracy. In this example, the accuracy determination unit 234 calculates the variance of the received radio beacon as will be described later, and obtains an evaluation value of measurement accuracy based on the variance.

  And the said location and the evaluation value of a measurement precision are output as a positioning result (S70). For example, the map is displayed on the display device, and the location position is marked and displayed.

  As described above, the positioning accuracy is verified (S40), and the positioning can be performed with high accuracy by repeatedly performing positioning.

(6) Details of Positioning Processing FIG. 7 is an explanatory diagram of a method for positioning using radio signs from a plurality of radio stations 1. In FIG. 7, when the radio station 1 is shown individually, description will be made using individual codes such as radio stations 1-1, 1-2, and 1-3. FIG. 7 shows a case where three radio signs from the radio stations 1-1, 1-2 and 1-9 are received.

The output of the radio beacon from each radio station 1-1, 1-2, 1-9 is set to 1.6 mW, and the positioning device 2 determines each radio station 1-1 from the received electric field strength of each radio beacon. , 1-2, and 1-9.

Here, when the distance to the radio station 1-1 is r1, the positioning device 2 exists on the circumference R1 having the radius r1 with the installation position (135, 256) of the radio station 1-1 as the center. I understand. Similarly, when the distance from the radio station 1-2 is r2, the installation position of the radio station 1-2 (235, 2
56) When the positioning device 2 exists on the circumference R2 having the radius r2 with the center at 56) and the distance from the radio station 1-9 is r9, the installation position (185, 356) of the radio station 1-9 is determined. Center radius r9
It can be seen that the positioning device 2 exists on the circumference R9. Therefore, it can be determined that the location 91 where the circumferences R1, R2, and R9 intersect is the current position of the positioning device 2.

  In the above example, three pieces of label information are used. However, the present invention is not limited to this, and four or more pieces of label information may be used. In addition, when two pieces of beacon information are used, for example, in the example of FIG. However, the position of the positioning device 2 can be determined based on two marker information by setting a selection condition in advance, such as taking the middle of the two locations 90 and 91 or taking the one closer to the previous positioning point. May be required. Further, even when the two sign information from the radio stations 1-1 and 1-2 are used, if the positioning device 2 is located near the straight line 93 connecting the radio station 1-1 to the radio station 1-2, positioning is performed. The position can be narrowed down to one place.

  When the user terminal that has received a plurality of radio signs transmits the identification information and electric field strength of each radio beacon to the location information server 2, the location information server 2 detects the location information and the electric field strength of each radio station 1 corresponding to the identification information. The current position of the positioning device 2 is specified from the distance based on the position information and the position information is transmitted to the positioning device 2 as shown in FIG. As described above, the position is preferably specified by the position information server 2, but is not limited to this, and the positioning device 2 may obtain the position. For example, the received identification information of the radio beacon is sent to the position information server 2, the coordinate information of each radio station 1 is acquired, and based on the distance between each coordinate station and each radio station based on the electric field strength, as shown in FIG. Alternatively, the current position of the positioning device 2 may be obtained.

  In the above example, the distance to the radio station 1 is obtained based on the electric field strength of the received radio beacon. However, the present invention is not limited to this, and the radio beacon is output from the radio station 1 and received by the positioning device 2. The distance between the radio station 1 and the positioning device 2 is obtained based on the time taken until the position of the positioning device 2 is obtained as described above from the distance to each radio station 1 and the identification information of each radio station. Also good.

(7) Evaluation of positioning accuracy The positioning accuracy is related to the distance between a radio station that is a transmission source of a plurality of radio signs used for positioning and the measurement position, and the dispersion of the distance between each radio station and the measurement position increases. , Tend to increase. Here, since the distance between each radio station and the measurement position correlates with the radio field strength of the radio beacon, the positioning accuracy tends to increase as the dispersion of the radio field intensities of the plurality of radio beacons used for positioning increases. I can say that. This can be confirmed by the following experiment.

  FIG. 8 is a diagram showing the arrangement of radio stations when conducting an experiment to obtain the relationship between the dispersion of radio field intensity and positioning accuracy, FIG. 9 is a diagram showing measurement results, and FIG. 10 is the correspondence between dispersion values and positioning errors. FIG. 11 is a graph showing a change in positioning error due to a difference in dispersion.

In this experiment, as shown in FIG. 8, the radio stations 1-14 to 1-17 were arranged in a straight line in an indoor passage. Here, the longitudinal direction of the passage is defined as the Y axis, the width direction of the passage is defined as the X axis, the coordinates of each radio station and measurement point are represented by (X, Y), and the unit is represented by meters [m]. The radio stations 1-17 are arranged at the coordinates (0, 0), and the radio stations 1-16, 1-15, 1-14 are arranged 20 m apart from each other in the Y-axis direction. That is, the coordinates of the wireless station 1-16 20m away from the wireless station 1-17 at the coordinate (0, 0) in the Y-axis direction are (0, 20), and the coordinates of the wireless station 1-15 are (0, 40). ), The coordinates of the radio station 1-14 are (0, 60).

  In this way, four radio base stations are arranged, and the measurement point is moved by 1 m between the radio station 1-16 (0, 20) and the radio station 1-15 (0, 40), and received from each radio station. Positioning is performed based on the radio field strength of the radio beacon. Then, an error is obtained by comparing the positioning result and the coordinates of the measurement position, and the relationship between the error and the dispersion of the radio field intensity of the radio beacon used for positioning is obtained.

  In this experiment, as shown in FIG. 9, the measurement is repeated every 2 seconds at each measurement position, and the dispersion and error of the radio field intensity of the radio beacon received at each measurement are obtained.

  For example, at time 00:00 in FIG. 9, measurement is performed at coordinates (0, 20), two radio signs are received, the variance is 6.25, and the error is 6.977362434. Similarly, positioning is repeated a predetermined number of times every 2 seconds, such as time 00:00:02, 00:00:04, and the error and variance are obtained.

  Then, after positioning a predetermined number of times at coordinates (0, 20), the measurement position is moved by 1 m and positioning is performed at coordinates (0, 21). For example, at time 00:00:56, measurement is performed at coordinates (0, 20), two radio signs are received, the variance is 64.222222222, and the error is 1.000000000. Thereafter, positioning is repeated a predetermined number of times every 2 seconds, and the error and variance are obtained at each measurement position.

  FIG. 10 shows an average error value obtained for each dispersion value of the radio field intensity for the positioning result. For example, a plurality of 28.282224206, 20.60641667, 10.05063657, 8.680076628, 6.1868868687, 2.548309179, 1.575000000, 0.708333333, 0 are set as thresholds for dispersion of radio wave intensity. The average error of the positioning results was calculated.

  FIG. 11 is a graph in which the data of FIG. 10 is plotted with the value of variance on the horizontal axis and the error on the vertical axis.

  As shown in FIGS. 10 and 11, the higher the variance of the received intensity, the smaller the error, that is, the positioning accuracy can be increased.

  In the above example, as shown in FIG. 9, positioning was performed by sampling one radio beacon from each radio station every two seconds, but generally, radio beacons are repeatedly transmitted in a short time. A configuration may be adopted in which a plurality of radio signs are received from each radio station in one positioning. For example, in the case of a wireless LAN, radio beacons (beacon signals) are sent at 50 msec intervals, so if the sampling period for each measurement is set to about 100 m, two radio signs from each radio station can be received. become. Similarly, a longer sampling period may be used so that three or more radio signs can be received from each radio station.

  FIG. 12 shows changes in positioning error due to differences in dispersion when there are two radio labels (samples) received from each radio station. Further, FIG. 13 shows a change in positioning error due to a difference in dispersion when there are three radio beacons (samples) received from each radio station.

  As shown in FIGS. 11 to 13, when the number of radio signs received in one positioning is increased, the positioning error tends to be reduced, that is, the positioning accuracy tends to be improved.

As described above, since the positioning accuracy correlates with the dispersion of the radio field strength of the radio beacon, the accuracy determination unit 234 obtains the evaluation value of the positioning accuracy based on the dispersion of the radio field strength of the radio beacon. FIG. 14 illustrates an evaluation table for obtaining an evaluation value of positioning accuracy.

  In the example of FIG. 14, the dispersion value and the evaluation value of the positioning accuracy are associated with each other. If the dispersion value V is 28 or more, the evaluation value of the positioning accuracy is 5 and the dispersion value V is less than 28 and 20 or more. If there is a positioning accuracy evaluation value of 4, if the dispersion value V is less than 20 and 8 or more, the positioning accuracy evaluation value is 3, and if the dispersion value V is less than 8 and 2 or more, the positioning accuracy evaluation value is 2. If the variance value V is less than 2, the evaluation value of positioning accuracy is 1.

  In step S60, the accuracy determination unit 234 refers to the evaluation table in FIG. 14 and obtains an evaluation value corresponding to the dispersion of the radio field intensity of the radio marker used for positioning. The evaluation value is not limited to this, and other calculation methods may be used. Further, the evaluation value may be a dispersion value of the radio field intensity of the radio beacon or a positioning error value itself.

(8) Display of Evaluation Value The output control unit displays the positioning result on the display device in step S70 of FIG. In FIG. 15A, the output control unit displays icons 82 at corresponding locations on the map 81 based on the position information obtained by positioning. Then, a number of marks (stars in FIG. 15A) 83 corresponding to the evaluation value of the positioning accuracy is displayed on the upper left of the screen. Thereby, the location and evaluation value as a positioning result are output (displayed).

  In the example of FIG. 15A, the evaluation value is indicated by the star 83, but the evaluation value may be displayed as a number instead of the number of the star 83. The display position of the evaluation value is not limited to the upper left, but may be another position. For example, FIG. 15B shows an example in which the evaluation value is displayed as a number in the icon 82.

  Further, the display state of the icon 82 may be changed according to the evaluation value. For example, the icon 82 may be displayed in a color according to the evaluation value, such as green when the evaluation value is high, yellow when the evaluation value is low, and red when the evaluation value is low. Similarly, the icon 82 may be displayed with a density or luminance according to the evaluation value. Further, the icon 82 may be blinked and displayed according to the evaluation value. For example, if the evaluation value is high, the light is always on, and the lower the evaluation value, the faster the blinking.

  As a result, the user can know how accurate the position display is with the current position.

  FIG. 15C shows an example in which a circle 84 having a size corresponding to the evaluation value is displayed around the location. For example, when the evaluation value is low and the error is large, the circle 84 is displayed large, and when the evaluation value is high and the error is small, the circle 84 is not displayed or displayed small. Here, since the size of the circle 84 is based on the evaluation value, it also correlates with the size of the error. Therefore, the magnitude of the error may be obtained according to the evaluation value, and a circle 84 having a size corresponding to this error may be displayed based on the scale of the map 81. That is, if the error is 10 m, a 10-meter circle 84 centered on the location is displayed on the map 81, and if the error is 2 m, the location is displayed on the 2-meter circle 84 map 81. As a result, it is possible to indicate a range in which there is a possibility of deviation due to an error. In this case, it is desirable that the size of the circle 84 also changes in conjunction with changing the scale of the map 81.

(9) Effect As described above, according to this embodiment, it is possible to perform positioning with high accuracy based on the radio field intensity of the radio beacon received from the radio station. Moreover, the accuracy of positioning can be shown based on the dispersion | distribution of the radio field intensity of the radio | wireless label | marker used for positioning.

<Modification>
In the above embodiment, in step S40, the positioning is repeated to determine whether or not the positioning accuracy is improved based on the radio beacon received from the neighboring station. In addition to this, in the present modification, the moving speed of the terminal Whether or not to repeat positioning is determined based on the above. Since other configurations are the same as those of the above-described embodiment, the same elements are denoted by the same reference numerals and the description thereof is omitted.

FIG. 16 is an explanatory diagram showing a positioning method according to this modification.
The communication device 215 receives a wireless sign from the wireless station 1 (S10), obtains a distance from the wireless station based on the received wireless sign, and based on the distance from the wireless station and the position of the wireless station. Positioning is performed to determine the location (position where the positioning device 2 is present) (S20).

  The extracting unit 232 refers to an arrangement table (FIG. 4) indicating the positions of a plurality of radio stations, and extracts radio stations that are within a predetermined range from the location obtained in step S20 as neighboring stations (S30).

  Further, the acceleration sensor 216 detects the acceleration and inputs it to the CPU 201, and the CPU 201 obtains the movement amount of the user terminal 2 (S35).

  The accuracy determination unit 234 determines whether or not the positioning accuracy is increased based on the movement state of the user terminal 2 and, when positioning is performed using a radio beacon from the adjacent station, positioning is performed rather than positioning of the location. It is determined whether or not the accuracy is increased (S40). For example, when it is determined that the user terminal 2 is moving, i.e., not stationary, it is determined that the positioning accuracy is not increased because a shift occurs when the positioning is repeatedly performed. That is, positioning is not repeated in step S50. On the other hand, if it is determined that the user terminal 2 is not moving, it is determined whether or not the positioning accuracy is increased by using a radio beacon from a neighboring station.

  In the above example, it is determined that the positioning accuracy does not increase if the user terminal 2 moves even a little. However, the present invention is not limited to this, and the movement amount is not more than a predetermined value even if the user terminal 2 is moving. May determine whether or not the positioning accuracy is increased by using a radio beacon from a neighboring station.

  For example, if the movement amount is equal to or greater than a predetermined value (threshold), it is determined that the positioning accuracy does not increase. If the movement amount is less than the predetermined value, it is determined whether or not the positioning accuracy is increased using a radio beacon from a neighboring station. You may judge.

  In addition, the positioning error based on the dispersion of the radio field intensity is compared with the movement amount. If the movement amount is equal to or greater than the positioning error or the difference between the movement amount and the positioning error is equal to or less than the predetermined value, it is compared with the width where the error is reduced by repeating the positioning. Therefore, it may be determined that the positioning accuracy is not improved.

  For example, when the user terminal 2 is moving at 4 km / h, the amount of movement for 2 seconds is about 2.2 m. Therefore, even if the positioning error is changed from 4 m to 3 m after repeated positioning in 2 seconds, 2. Since it will move 2m, positioning accuracy does not improve. Therefore, when the difference between the movement amount during positioning is repeated (for example, 2 seconds) and the positioning error is equal to or less than a predetermined value (for example, 2 m), it may be determined that the positioning accuracy does not increase even if positioning is repeated.

  When it is determined that the positioning accuracy is improved based on the determination result of step S40, the re-positioning control unit 234 returns to step S10, and again determines the positioning unit 231 based on the radio beacon received from the neighboring station. The location is obtained (S50).

Next, when the accuracy determination unit 234 determines that the positioning accuracy does not increase, the output control unit 235 moves the process to step S60, and causes the accuracy determination unit 234 to evaluate the measurement accuracy. In this example, the accuracy determination unit 234 calculates the variance of the received radio beacon as will be described later, and obtains an evaluation value of measurement accuracy based on the variance.

  And the evaluation value of the said location, moving speed, and measurement accuracy is output as a positioning result (S70).

  As described above, according to the present modification, it is possible to determine whether or not the positioning accuracy when the positioning is repeated is increased according to the movement amount of the user terminal 2, so that the positioning is appropriately performed without repeating the positioning unnecessarily. be able to.

<Others>
The present invention is not limited to the illustrated examples described above, and various modifications may be made without departing from the spirit of the present invention, such as combining the above-described elements.

10 Positioning system 1 Radio station (place sticker)
2 Positioning device

Claims (6)

A positioning device that performs positioning based on a radio sign received from a radio station,
A receiver for receiving a radio beacon from the radio station;
Obtaining the distance to the wireless station based on the received radio indicator, positioning based on the distance to the wireless station and the position of the wireless station, a positioning unit for obtaining the location,
An extraction unit that refers to an arrangement table indicating positions of a plurality of wireless stations, and extracts a wireless station within a predetermined range from the location as a neighboring station;
When comparing the distance from the radio station that has received the radio beacon to the location and the distance from the proximity station to the location, and positioning using the radio beacon from the proximity station, the location of the location An accuracy determination unit that determines whether positioning accuracy is higher than positioning;
When it is determined that the positioning accuracy is increased, a re-positioning control unit that causes the positioning unit to obtain a location again based on a radio sign received from the proximity station;
Positioning device equipped with.   The positioning apparatus according to claim 1, further comprising: an output control unit that outputs information indicating the positioning accuracy obtained by the accuracy determination unit as a positioning result together with information on the location.   The positioning device according to claim 2, wherein the positioning accuracy is indicated by a predetermined number of marks, icon state change, or a circle centered on the location.   The positioning device according to any one of claims 1 to 3, further comprising an output control unit that outputs the location as a positioning result when the accuracy determination unit determines that the positioning accuracy does not increase. A positioning device is a method for positioning based on a radio beacon received from a radio station,
Receiving a radio beacon from the radio station;
Obtaining a distance from the wireless station based on the received wireless sign, performing positioning based on the distance to the wireless station and the position of the wireless station, and obtaining a location position;
Referring to an arrangement table showing positions of a plurality of radio stations, and extracting a radio station within a predetermined range from the location as a proximity station;
When comparing the distance from the radio station that has received the radio beacon to the location and the distance from the proximity station to the location, and positioning using the radio beacon from the proximity station, the location of the location Determining whether positioning accuracy is higher than positioning; and
When it is determined that the positioning accuracy is increased, the step of obtaining the location again based on the radio signal received from the neighboring station;
Positioning method to perform. A program for causing a computer to perform positioning based on a radio sign received from a radio station,
Receiving a radio beacon from the radio station;
Obtaining a distance from the wireless station based on the received wireless sign, performing positioning based on the distance to the wireless station and the position of the wireless station, and obtaining a location position;
Referring to an arrangement table showing positions of a plurality of radio stations, and extracting a radio station within a predetermined range from the location as a proximity station;
When comparing the distance from the radio station that has received the radio beacon to the location and the distance from the proximity station to the location, and positioning using the radio beacon from the proximity station, the location of the location Determining whether positioning accuracy is higher than positioning; and
When it is determined that the positioning accuracy is increased, the step of obtaining the location again based on the radio signal received from the neighboring station;
Positioning program to execute.

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