JP2000046939A - System and method for detecting position of wireless card and storage medium recording position detection program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a position detection system for accurately detecting a position and is capable of communication stably over the entire traveling path of a wireless card. SOLUTION: A wireless card position detection system consists of a wireless base station 10 for transmitting electronic waves, a wireless card 20 for measuring the strength of electric field by receiving the electronic waves, a control device 30, and a database 40 storing an electric field strength data. In this case, the wireless card receives the electronic waves and divides them into vertical and horizontal polarization constituents, and measures the electric field strength. The control device compares a measurement result according to the vertical polarization constituent with the database, indexes a first group of points where the wireless card exists, at the same time compares the measurement result according to the horizontal polarization constituent with the database, indexes a second group of points where the wireless card can exist, and specifies the position of the wireless card with the product set of the first and second groups of points.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system and method for detecting a position of a wireless terminal using a wireless terminal and a base station, and a recording medium storing a position detecting program.

[0002]

2. Description of the Related Art Conventionally, there has been a technique for detecting the position of a wireless terminal using the wireless terminal. Specifically, PHS (Pers
onal Handy-phone System) or a weak radio wave wireless card. PHS has a communication area of 100 radius
Utilizing the fact that the distance is in the range of m to several hundred meters, it is used for outdoor position detection, and is used for behavior management of people who have a wandering habit. Position detection using a weak radio wave wireless card can be performed indoors using the fact that the communication area radius of a radio base station is within a range of about 10 m, as disclosed in, for example, JP-A-9-200112. Used for position detection.

Here, the wireless card system will be described in detail. In a conventional wireless card system, a signal is transmitted from the wireless base station to the wireless card, and the wireless card receiving the signal returns an acknowledgment signal to the wireless base station, whereby the wireless card is recognized by the wireless base station. However, only one wave is transmitted from the wireless base station.

In such a system, for example, when a person holding a wireless card moves in a room to perform position detection, the wireless card measures the electric field intensity of a radio wave emitted from a wireless base station, and this measured value is used as a value. In some cases, the distance from the wireless base station to the wireless card is determined by returning a response to the wireless base station and checking the distribution against the electric field strength distribution stored in a database connected to the wireless base station.

[0005]

However, in a system for determining the distance from the wireless base station to the wireless card depending on the electric field strength of only one wave, the information may not be accurate. That is, the measurement value of the electric field strength is unavoidable to cause a measurement error due to the reception level fluctuation due to the surrounding environment, and sometimes has a value far from the electric field strength distribution obtained by the simulation stored in the database. . As a result, accurate position detection may not be performed in some cases.

Further, there are places where the electric field intensity drops sharply due to multipath, and radio waves from a wireless base station may not reach the wireless card depending on the position of the wireless card. In such a case, the control device cannot calculate the distance from the wireless base station, and communication between the wireless base station and the wireless card may be interrupted during the movement of the wireless card.

[0007] In particular, when used in a system in which the movement path of a wireless card is plotted every moment indoors and the behavior of a person having a wandering habit is managed, communication between the wireless base station and the wireless card is performed during the movement. There is a problem that the interruption makes it difficult to plot the position of the wireless card holder.

The present invention has been made in order to solve these problems, and provides a position detecting system capable of performing high-accuracy position detection and performing stable communication over the entire moving path of a wireless card. Is what you do.

[0009]

According to a first aspect of the present invention, there is provided at least one wireless base station for transmitting a radio wave, receiving a radio wave from the wireless base station, and measuring an electric field strength of the received radio wave. A wireless card location comprising at least one wireless card, a controller connected to the wireless base station, and a database connected to the controller and storing a plurality of field strength distribution data. In the detection system, the wireless card is provided with an antenna for receiving a radio wave, and the antenna receives a radio wave emitted from a wireless base station and converts the radio wave into a vertical polarization component and a horizontal polarization component. The wireless card measures the field strength separated into vertical and horizontal polarization components, and compares the measurement results to the wireless base station. Returns to the control device via the controller, the control device checks the measurement result obtained by the vertical polarization component with the database to determine the first group of points where the wireless card can exist, Collating the obtained measurement result with a database to determine a second group of points where the wireless card can be located, and specifying the position of the wireless card based on an intersection of the first group of points and the second group of points A wireless card position detection system characterized by the following.

According to a second aspect of the present invention, the wireless base station transmits a radio wave a plurality of times at different times, and the control device controls the vertical polarization component and the horizontal polarization component of the radio wave transmitted a plurality of times. 2. The wireless card position detecting system according to claim 1, wherein the position of the wireless card is specified by using a set of intersections of points where the wireless card can be located.

According to a third aspect of the present invention, the wireless base station simultaneously transmits a plurality of radio waves having different transmission frequencies, and the control device controls a vertical polarization component and a horizontal polarization component of the radio waves having different frequencies. The wireless card position detecting system according to claim 1 or 2, wherein the position of the wireless card is specified by using a set of intersections of points where the wireless card can exist, which is determined from the components.

According to a fourth aspect of the present invention, the step of collating the measurement result of the electric field strength with the database, which is performed by the control device, comprises the steps of: converting a vertical polarization component and a horizontal polarization component of a plurality of radio waves into a wireless card; 4. The wireless card position detecting system according to claim 2, further comprising the step of:

According to a fifth aspect of the present invention, the database stores data relating to the ratio of the electric field strength between the vertical polarization component and the horizontal polarization component. The wireless card position detecting system according to any one of claims 1 to 4, wherein a ratio of an electric field strength to a horizontal polarization component is calculated and compared with the database to specify a position of the wireless card. is there.

According to a sixth aspect of the present invention, there is provided at least one wireless card for transmitting a radio wave, and at least one wireless base station for receiving a radio wave from the wireless card and measuring an electric field strength of the received radio wave. And a control device connected to the wireless base station, and a database connected to the control device and storing a plurality of electric field strength distribution data. The station is provided with an antenna for receiving radio waves, this antenna receives radio waves emitted from the wireless card, decomposes into a vertical polarization component and a horizontal polarization component,
The wireless base station measures the electric field strength decomposed into the vertical polarization component and the horizontal polarization component, sends the measurement result to the controller, and the controller checks the measurement result obtained by the vertical polarization component against the database Then, while determining a first group of points where the wireless card can exist, the measurement result obtained by the horizontal polarization component is compared with a database to determine a second group of points where the wireless card can exist, A wireless card position detection system characterized in that a position of a wireless card is specified by an intersection of a first point group and a second point group.

According to a seventh aspect of the present invention, in the wireless card, the wireless card emits a plurality of radio waves at different times, and the control device determines a vertical polarization component and a horizontal polarization component of the radio waves transmitted a plurality of times. 7. The wireless card position detecting system according to claim 6, wherein the position of the wireless card is specified by using an intersection of the determined points where the wireless card can exist.

The wireless card may simultaneously transmit a plurality of radio waves having different transmission frequencies, and the control device may control a vertical polarization component and a horizontal polarization component of the radio waves having different frequencies. 8. The wireless card position detecting system according to claim 6, wherein the position of the wireless card is specified by using a set of intersections of points where the wireless card can be located.

According to a ninth aspect of the present invention, the step of comparing the measurement result of the electric field strength with the database, which is performed by the control device, includes the step of converting the vertical polarization component and the horizontal polarization component of the plurality of radio waves into a wireless card. The wireless card position detecting system according to claim 7, further comprising a step of converting the position into coordinates of the wireless card.

According to a tenth aspect of the present invention, in the database, data relating to a ratio of electric field strength between a vertical polarization component and a horizontal polarization component is stored, and the control device includes:
10. The wireless device according to claim 6, wherein a ratio of an electric field strength between a vertically polarized wave component and a horizontally polarized wave component is calculated and compared with the database to specify a position of the wireless card. It is a card position detection system.

The invention according to claim 11 provides at least one
Wireless base stations transmit radio waves, the transmitted radio waves are received by at least one wireless card, the electric field strength of the received radio waves is measured, and the measurement result and a plurality of electric field strength data stored in a database are measured. In the wireless card position detection method for identifying the position of the wireless card, the wireless card receives a radio wave emitted from a wireless base station, breaks it down into a vertical polarization component and a horizontal polarization component, Measure the electric field strength of each decomposed polarization component, return the measurement result to the control device via the wireless base station, the control device compares the measurement result obtained by the vertical polarization component with the database, The first group of points where the wireless card can be located is determined, and the measurement result obtained by the horizontal polarization component is compared with the database, and Indexing the second point group Yaresukado may exist, a wireless card position detecting method characterized by identifying the location of the wireless card with a product set of the first point group and the second point group.

According to a twelfth aspect of the present invention, at least one
Wireless base stations transmit radio waves, the transmitted radio waves are received by at least one wireless card, the electric field strength of the received radio waves is measured, and the measurement result and a plurality of electric field strength data stored in a database are measured. In the wireless card position detection method for identifying the position of the wireless card, the wireless card receives a radio wave emitted from a wireless base station, breaks it down into a vertical polarization component and a horizontal polarization component, The decomposed electric field strength is measured, the measurement result is returned to the control device via the wireless base station, and the control device checks the measurement result obtained by the vertical polarization component with the database, and determines whether the wireless card exists. The first set of points that can be obtained is determined, and the measurement result obtained by the horizontal polarization To determine a second point group in which a wireless card can exist, and to specify a position of the wireless card based on an intersection of the first point group and the second point group. This is a recording medium on which a position detection program is recorded.

In general, it is known that the electric field intensity distribution due to the vertical polarization component is different from the electric field intensity distribution due to the horizontal polarization component. In the present invention, the different electric field strength distributions are used as a database for detecting the position of the wireless card, so that highly accurate position detection can be performed. In addition, the present invention complements a point that is not recognized only by a single polarization, so that stable communication without interruption of communication can be performed over the entire moving route.

[0022]

FIG. 1 shows the basic configuration of a wireless card position detecting system according to an embodiment of the present invention.
This system includes a wireless base station 10, a wireless card 20, a control device 30, and a database 40.

The wireless base station 10 is located at a predetermined coordinate position on a two-dimensional plane 50 for representing the coordinates on the system, and emits a radio wave to each coordinate position on the two-dimensional plane 50. It is assumed that the wireless card 20 exists anywhere on the two-dimensional plane 50. The wireless card 20 includes
An antenna having a function of receiving radio waves from the wireless base station 10 and decomposing the radio waves into a vertical polarization component and a horizontal polarization component, and a function of measuring the electric field strength of these components are mounted. Further, it has a function of returning the measured values of the electric field strengths of the vertical polarization component and the horizontal polarization component to the wireless base station 10.

In the polarization diversity reception that is generally used, the receiving antenna switches to the higher reception level of the vertical polarization component and the horizontal polarization component to be received to perform good communication. . However, the wireless card 20 in the present embodiment is provided with two orthogonal antennas, which divides a received radio wave into a vertical polarization component and a horizontal polarization component, and uses both of them.

The wireless base station 10 is connected to a control device 30 and is controlled by the control device 30. When the measured values of the electric field strengths of the vertical polarization component and the horizontal polarization component are returned from the wireless card 20 to the wireless base station 10, the measured values are transmitted to the control device 30.
Sent to

The control device 30 has a mapping for converting the vertical polarization component and the horizontal polarization component of the input electric field intensity measurement value into specific values on the electric field intensity distribution function. Time domain difference method, geometrical optics method, finite element method, etc. are known as methods for obtaining the electric field strength.The optimal method depends on the shape of the space to be measured, the presence or absence of obstacles, and the frequency of the radio wave used. We shall select the appropriate method.

The control device 30 further includes a database 4
0 is connected. The database 40 stores the electric field strength distribution of the vertical polarization component and the horizontal polarization component when the wireless base station 10 is placed at an arbitrary position.
The control device 30 calculates an area where the wireless card 20 can be present by comparing the electric field intensity measurement values of the vertical polarization component and the horizontal polarization component with the electric field intensity distribution stored in the database 40.

Next, the operation of the embodiment of the present invention will be described. The first to fifth embodiments described below all have the common configuration shown in FIG. That is,
It is assumed that there is one wireless base station 10 and one wireless card 20 on the two-dimensional plane 50. The position of the wireless base station 10 is fixed, and the wireless card 20 is stationary.

First, the operation of the first embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. FIG. 7 shows a flowchart of this operation. S1 to S11 in the following description indicate steps in this flowchart.

A radio wave having an electric field strength P ₀ and a frequency f ₀ is transmitted from the wireless base station 10. In the present embodiment, f ₀ = 300 MH
z. The wireless card 20 is the wireless base station 1
The radio wave transmitted from 0 is received by the antenna 21 and decomposed into a vertical polarization component P _0v and a horizontal polarization component P _0h (S1).
However, a ^{_{P 0v 2 + P 0h 2 =}} P 0 2. Wireless card 20
Measures the electric field strengths of these two components, and returns the measured values to the wireless base station 10 (S2). The wireless base station 10 sends the returned measurement value to the control device 30 (S
3).

The control device 30 calculates the transmitted measurement value,
Collating the electric field intensity distribution stored in the database 40, it calculates the position candidates that satisfy the electric field strength P _{0 v} of the vertical polarization component (S4~6), further the electric field strength of horizontally polarized wave component
Calculating a position candidate for satisfying P _0h (S7~9). Then, the position where the wireless card 20 can exist is calculated by multiplying the two position candidates (S10 to S11).
In the first embodiment, the collation with the database is performed.
P _0v and P _0h are performed in this order, but the order is arbitrary in actual use.

Next, the operation of the second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 8 and 9 show flowcharts of this operation. FIG. 8 shows a continuation of FIG. Also, S12 to S12 in the following description
S24 shows the steps in these flowcharts.

A radio wave having an electric field strength P ₀ and a frequency f ₀ is transmitted from the wireless base station 10. At time t _1, the wireless card 20 receives radio waves from the wireless base station 10, is decomposed into vertical polarization component P _{1 v} and a horizontal polarization component P _1h by the antenna 21 (S12). However, P _1v ² + P _1h ²
= P ₀ ² The wireless card 20 measures the electric field strength of each component (S13), and returns the measured value to the control device 30 via the wireless base station 10 (S14). The control device 30 stores the received measurement values in the database 40
Is compared with the electric field intensity distribution stored in (S14).
a), position coordinate group (X ₁ , Y ₁ ) corresponding to electric field strengths P _1v and P _1h
Is calculated (S15 to S17). Next, at time t _2, the as with the time t ₁ wireless card 20 receives the radio waves, the measured value of the vertical polarization component P _2v and the horizontal polarization component P _2h is sent to the control device 30 (S18~20) . The control device 30
The received measurement value is compared with the electric field intensity distribution stored in the database 40 (S20a), and the electric field intensity P
_2v , a position coordinate group (X ₂ , Y ₂ ) corresponding to P _2h is calculated (S2
1 to 23).

The control device 30 operates at time t₁Position coordinate group in
And time t_TwoAt the time t₁Or
T_TwoCoordinates where the wireless card 20 can exist between
Group (X ₀, Y₀) Is calculated (S24).

[0035] Incidentally, in the second embodiment is performed to calculate the position candidates at later time t ₂ which calculates the position candidate of the wireless card at time t _1, but the position candidates at once at time t ₂ It may be calculated. That is, time t ₂
At this time, the position coordinates (X ₀ , Y ₀ ) corresponding to the four variables of the electric field strengths P _1v , P _1h , P _2v , and P _2h may be calculated. Further, if the measurement interval of the electric field intensity is shortened, the position where the wireless card can exist can be narrowed down by that much.

Next, a third embodiment of the present invention will be described with reference to FIG. The flowchart of this operation is shown in FIG.
0 and FIG. FIG. 10 shows a continuation of FIG. In addition, S25 in the following description
S34 show steps in these flowcharts.

A radio wave having an electric field strength P ₀ and a frequency f _{1 and} a radio wave having an electric field strength P ₀ and a frequency f ₂ are simultaneously transmitted from the wireless base station 10. However, f ₁ and f ₂ are different from one another. In the wireless card 20, these two waves having different frequencies are decomposed by the antenna 21 into a vertical polarization component and a horizontal polarization component, respectively (S25). The vertical polarization component and the horizontal polarization component of the radio wave of the frequency f _{1 at} the receiving point are P _1v and P _1h , respectively, and the vertical polarization component and the horizontal polarization component of the radio wave of the frequency f ₂ are P _2v and P _2h , respectively. .

The wireless card 20 measures the electric field strength of each decomposed polarization component, and returns the measured value to the control device 30 via the wireless base station 10 (S26 to S26).
7). Control device 30, the measured values P _{1 v,} the position coordinate group A which satisfies P _1h the (X _1, Y ₁₎ is calculated by the function g ₁ (S27a~3
0), a position coordinate group B (X ₂ , Y ₂ ) satisfying the measured values P _2v and P _2h is calculated by the function g ₂ (S30a to S33). here,
Generally, electric field strength distributions of radio waves having different frequencies are different. Therefore, a position coordinate group (X ₀ , Y ₀ ) where the wireless card 20 can exist is calculated by a function h which takes the product of these two position candidate groups A and B (S34).

[0039] In the third embodiment, each of the field intensity component _{P 1v, P 1h, P 2v} , the P _2h function g _1, g ₂ by the position coordinate group _{A (X 1, Y 1)} , B (X ₂ , Y ₂ ), and then position coordinates (X ₀ , Y ₀ ) are obtained by the function h, but the four variables P _1v , P _1h , P _2v , and P _2h are converted to the function g ₁ * g ₂ * h may be directly converted to position coordinates (X ₀ , Y ₀ ).

Next, the operation of the fourth embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 12 and 13 show flowcharts of this operation. FIG. 12 shows a continuation of FIG. In addition, S35 to S51 in the following description indicate steps in these flowcharts.

First, at time t ₁ , the wireless card 20 receives a radio wave from the wireless base station 10 and decomposes it into a vertical polarization component P _1v and a horizontal polarization component P _1h (S3).
5). The decomposed measured values P _1v and P _1h are sent to the control device 30 (S36 to S37), and the sent measured values are sent to the control device 30.
P _{1 v,} calculates the electric field strength P ₁ from P _1h. However, a ^{_{P 1v 2 + P 1h 2 =}} P 1 2. Next, the proportional constants α and β are calculated (S38).
However, a _{P 1v = αP 1 P 1h =} βP 1. Then, β / α is calculated from the calculated α and β (S39). Further, the control device 30 checks the calculated β / α with the electric field intensity distribution stored in the database 40 (S39a), and calculates a region satisfying β / α (S40 to S42).

Next, at time t _2, the operations similar to those in the time t _1. That is, the wireless card 20 receives a radio wave from the wireless base station 10 and decomposes the radio wave into a vertical polarization component P _2v and a horizontal polarization component P _2h (S43). These measured values P _2v and P _2h are _stored in the control device. 30 (S44-4
5). Controller 30, these measurements P _2v, the electric field strength P ₂ calculated from P _2h, calculates the γ and δ (S46), δ
/ γ is calculated (S47). Here, P _2v ² + P _2h ² = P ₂ ² P _2v = γP ₂ P _2h = ΔP ₂ . Further, the control device 30 compares the calculated δ / γ with the electric field intensity distribution stored in the database 40 (S47a), and calculates a region satisfying δ / γ (S47).
48-50). Finally, the control device 30, the by taking the product of the two areas, wireless card 20 between t ₂ to calculate the area that may be present from time t ₁ (S5
1).

Next, the operation of the fifth embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 14 and 15 show flowcharts of this operation. FIG. 14 shows a continuation of FIG. S52 to S65 in the following description indicate steps in these flowcharts.

A radio wave having the electric field strength P ₁ and the frequency f _{1 and} a radio wave having the electric field strength P ₂ and the frequency f ₂ are simultaneously transmitted from the wireless base station 10. However, f ₁ and f ₂ are different from one another. The wireless card 20 decomposes two waves having different frequencies emitted from the wireless base station 10 by the antenna 21 into a vertical polarization component and a horizontal polarization component, respectively (S52). Frequency f ₁ of the radio wave of the vertically polarized wave component and horizontally polarized wave component, respectively P _{1 v,} P _1h, the frequency f ₂ of the radio wave of the vertical polarization component and the respective P _2v horizontally polarized component, and P _2h. These measured values P _1v , P _1h , P _2v , P _2h are
0 (S53-S54).

The control device 30 calculates β / α and δ / γ based on the measured values transmitted from the wireless card 20 (S55 to S58). However, a _{^{P 1v 2 + P 1h 2 =}} P 1 2 P 1v = αP 1 P 1h = βP 1 P 2v 2 + P 2h 2 = P 2 2 P 2v = γP 2 P 2h = δP 2.

Further, the controller 30 calculates the calculated β / α
And δ / γ are compared with the electric field intensity distribution stored in the database 40, and a region satisfying β / α and δ / γ is calculated (S58a to S58). Finally, the control device 30
Calculates the product of these two areas as the wireless card 2
An area where 0 may exist is calculated (S65).

In the fourth and fifth embodiments, the area where the wireless card 20 can exist is calculated only by the ratio between the electric field strengths of the vertical polarization component and the horizontal polarization component. Therefore, even electric field intensity P ₁ or P ₂ fluctuates temporally in some point, the value of beta / alpha and [delta] / gamma is unchanged. Although the electric field strength is susceptible to temporal fluctuations due to external noise or the like, the use of the above system enables stable position detection not affected by the temporal fluctuations in the electric field strength. In the fourth and fifth embodiments, β
Although the control device 30 calculates / α and δ / γ, the calculation function may be mounted on the wireless card 20 side.

In each of the first to fifth embodiments, a case has been described in which one wireless base station 10 and one wireless card 20 are provided, but a plurality of wireless base stations and a plurality of wireless cards are provided. Can also be used. When a plurality of wireless base stations are provided, the same operation as in the above embodiment can be performed by changing the frequency of the radio wave to be emitted. In addition, interference between base stations may be avoided by time-divisionally controlling a plurality of wireless base stations. When a plurality of wireless cards are used, each wireless card can be recognized by transmitting an ID number from these wireless cards.

In each of the first to fifth embodiments, a system in which a device for separating each polarization component is mounted on a wireless card has been described. As a configuration for receiving the radio wave, a device for separating each polarization component may be mounted on the wireless base station. In this case, since the wireless card transmits radio waves and the wireless base station only receives radio waves from the wireless card, the number of transmission / reception devices can be one, and the configuration can be simpler.

Further, in each of the first to fifth embodiments, the case where the wireless card 20 is stationary has been described. The location of the wireless card can be detected.

Further, a program for executing the above-described process is stored in a portable storage medium such as a disk device, a floppy disk, or a CD-ROM connected to the control device, and is controlled when executing the present invention. The above process can also be realized by installing on a device.

[0052]

As described above, the present invention provides at least one wireless base station for transmitting radio waves, at least one radio base station for receiving radio waves from the wireless base station, and measuring the electric field strength of the received radio waves. Wireless card, a controller connected to the wireless base station, and a database connected to the controller and storing a plurality of electric field intensity distribution data. The wireless card is provided with an antenna for receiving a radio wave, the antenna receives a radio wave emitted from a wireless base station, decomposes into a vertical polarization component and a horizontal polarization component, The wireless card measures the electric field strength decomposed into a vertical polarization component and a horizontal polarization component, and transmits the measurement result via the wireless base station. Reply to the control device, the control device,
The measurement result obtained by the vertical polarization component is compared with the database to determine a first group of points where the wireless card can exist, and the measurement result obtained by the horizontal polarization component is compared with the database, The wireless card position detection system is characterized in that a second group of points where a card can be located is determined, and the position of the wireless card is specified by the intersection of the first group of points and the second group of points. Since the area where the wireless card can be present is calculated from the electric field strengths of the wave component and the horizontally polarized wave component, the position of the wireless card can be narrowed down more than when a single radio wave is used, and highly accurate position detection is performed. be able to.

Further, by using this system, a place where radio waves cannot be received by a vertically polarized receiving antenna can be complemented by a horizontally polarized receiving antenna, and vice versa. It is possible to perform stable wireless base station / wireless card communication without interruption of communication over the entire moving path of the card.

Further, the wireless base station simultaneously transmits a plurality of radio waves having different transmission frequencies, and the control device controls the wireless base station based on the vertical and horizontal polarization components of the radio waves having different frequencies. if identifying the position of the wireless card with a product set of existing point group capable of cards, where not reach the radio wave at the frequency f ₁ supplemented by radio frequency f _2, and because it can supplement also vice versa Thus, stable communication between the wireless base station and the wireless card can be performed without interruption over the entire moving path of the wireless card.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of an embodiment of the present invention.

FIG. 2 is a diagram illustrating a method of detecting a position where a wireless card may exist.

FIG. 3 is a diagram illustrating a method for detecting a position where a wireless card may exist.

FIG. 4 is a diagram illustrating a method for detecting a position where a wireless card may exist.

FIG. 5 is a diagram illustrating a method for detecting a position where a wireless card may exist.

FIG. 6 is a diagram illustrating a method for detecting a position where a wireless card may exist.

FIG. 7 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 8 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 9 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 10 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 11 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 12 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 13 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 14 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 15 is a flowchart showing the operation of the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 wireless base station 20 wireless card 21 antenna 30 control device 40 database 50 two-dimensional plane

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Naofumi Suzuki 3-19-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Japan Telegraph and Telephone Co., Ltd. No. Nippon Telegraph and Telephone Corporation (72) Inventor Hideki Nakajima 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo F-Term within Nippon Telegraph and Telephone Corporation 5J070 AB01 AC01 AC02 AD06 AD15 AE09 AH33 AK22 BC06 BC08 BC14 BC29 5K067 AA23 BB33 DD44 EE02 FF03 JJ53 JJ54 KK01

Claims (12)

[Claims] At least one wireless base station for transmitting a radio wave, at least one wireless card for receiving a radio wave from the wireless base station and measuring an electric field strength of the received radio wave, and the wireless base station And a database connected to the control device and storing a plurality of electric field intensity distribution data, wherein the wireless card receives a radio wave. This antenna receives radio waves emitted from a wireless base station and decomposes the signals into a vertically polarized component and a horizontally polarized component. The electric field strength decomposed into the polarization component is measured, and the measurement result is returned to the control device via the wireless base station. Compares the measurement result obtained by the vertical polarization component with the database to determine a first group of points where the wireless card can exist, and checks the measurement result obtained by the horizontal polarization component with the database. A wireless card position detecting system for determining a second group of points where a wireless card may exist, and specifying a position of the wireless card by an intersection of the first group of points and the second group of points. 2. The wireless base station transmits a radio wave a plurality of times at staggered times, and the control device controls the wireless card calculated from a vertical polarization component and a horizontal polarization component of the radio waves transmitted a plurality of times. The wireless card position detecting system according to claim 1, wherein the position of the wireless card is specified by using a set of intersections of points where the wireless card can exist. 3. The wireless base station transmits a plurality of radio waves having different transmission frequencies at the same time, and the control device transmits the radio waves having different frequencies from the vertical polarization component and the horizontal polarization component of the radio waves having different frequencies. 3. The wireless card according to claim 1, wherein the position of the wireless card is specified by an intersection of points where the card can exist.
A wireless card position detection system according to claim 1. 4. The step of collating the measurement result of the electric field strength with the database, performed by the control device, is a step of converting the vertical polarization component and the horizontal polarization component of the plurality of radio waves into position coordinates of a wireless card. The wireless card position detecting system according to claim 2, wherein the wireless card position detecting system comprises: 5. The database stores data relating to the ratio of the electric field strength between the vertical polarization component and the horizontal polarization component, and the control device controls the electric field between the vertical polarization component and the horizontal polarization component. The wireless card position detecting system according to any one of claims 1 to 4, wherein an intensity ratio is calculated and compared with the database to specify a position of the wireless card. 6. At least one wireless card for transmitting a radio wave, at least one wireless base station for receiving a radio wave from the wireless card and measuring an electric field strength of the received radio wave, In a wireless card position detecting system comprising a connected control device and a database connected to the control device and storing a plurality of electric field strength distribution data, the radio base station receives a radio wave. This antenna receives radio waves emitted from the wireless card and decomposes the signals into a vertical polarization component and a horizontal polarization component. The electric field strength decomposed into wave components is measured, and the measurement result is sent to the control device. The obtained measurement result is compared with a database to determine a first group of points where the wireless card can exist, and the measurement result obtained by the horizontal polarization component is compared with the database to determine whether the wireless card exists. A wireless card position detecting system, wherein a second point group is determined, and a position of the wireless card is specified by an intersection of the first point group and the second point group. 7. The wireless card transmits a radio wave a plurality of times at staggered times, and the control device controls the wireless card calculated from the vertical polarization component and the horizontal polarization component of the radio wave transmitted a plurality of times. 7. The wireless card position detecting system according to claim 6, wherein the position of the wireless card is specified based on a set of possible points. 8. The wireless card transmits a plurality of radio waves having different transmission frequencies at the same time, and the control device is configured to determine a wireless card which is calculated from a vertical polarization component and a horizontal polarization component of the radio waves having different frequencies. The position of the wireless card is specified by using a set of intersections of points that can exist.
A wireless card position detection system according to claim 1. 9. The step of comparing the measurement result of the electric field strength with the database, performed by the control device, is a step of converting a vertical polarization component and a horizontal polarization component of a plurality of radio waves into position coordinates of a wireless card. The wireless card position detecting system according to claim 7, wherein the wireless card position detecting system comprises: 10. The database stores data on the ratio of the electric field strength between the vertical polarization component and the horizontal polarization component, and the control device controls the electric field between the vertical polarization component and the horizontal polarization component. 10. The wireless card position detecting system according to claim 6, wherein a ratio of intensity is calculated and compared with the database to specify a position of the wireless card. 11. At least one wireless base station transmits radio waves, at least one wireless card receives the transmitted radio waves, measures the electric field strength of the received radio waves, and stores the measurement results and a database. In the wireless card position detecting method for comparing the obtained plurality of electric field strength data and specifying the position of the wireless card, the wireless card receives a radio wave emitted from a wireless base station, a vertical polarization component and horizontal Decompose into polarization components, measure the electric field strength of each decomposed polarization component,
The measurement result is returned to the control device via the wireless base station, and the control device compares the measurement result obtained by the vertical polarization component with the database to determine a first group of points where the wireless card can be located, and , A measurement result obtained by the horizontal polarization component is compared with a database to determine a second point group where the wireless card can exist, and a wireless card is set based on an intersection of the first point group and the second point group. A wireless card position detecting method, wherein the position of the wireless card is specified. 12. At least one wireless base station transmits radio waves, at least one wireless card receives the transmitted radio waves, measures the electric field strength of the received radio waves, and stores the measurement results and a database. In the wireless card position detecting method for comparing the obtained plurality of electric field strength data and specifying the position of the wireless card, the wireless card receives a radio wave emitted from a wireless base station, a vertical polarization component and horizontal It decomposes into polarization components, measures the decomposed electric field strength, returns the measurement result to the control device via the wireless base station, and the control device checks the measurement result obtained by the vertical polarization component against the database. To determine the first group of points where the wireless card can be located, and to store the measurement results obtained by the horizontal polarization component in a database. A second point group in which the wireless card can be located by comparing the first point group with the first point group, and identifying the position of the wireless card based on an intersection of the first point group and the second point group. A recording medium on which a position detection program for executing the position detection method is recorded.