JP2009229175A - Position detection system and management system using this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the number of installed master devices, and broaden a detectable area without lowering the accuracy of detection of the positions of a person and an object, on the occasion of detecting their positions by using the intensities of radio waves. <P>SOLUTION: This position detection system 1 includes a plurality of master devices 3a, 3b which are installed at predetermined positions and transmit radio waves, and a plurality of slave devices 2a, 2b which receive the radio waves from the plurality of master devices 3a, 3b and detect the intensities of the radio waves, and the system pinpoints the positions of the slave devices 2a, 2b by finding the distances between the master devices and the slave devices from the detected radio-wave intensities. Each of the plurality of slave devices 2a, 2b includes an inter-slave-device communication section 22 for performing radio-wave transmission and reception between the slave devices, and a radio-wave intensity detection section 23 for detecting the intensity of a radio wave received by the communication section 22 and calculating the distance between the slave devices. The detection system 1 interpolatively uses the distance between the slave devices calculated by the detection sections 23 to pinpoint the positions of the slave devices 2a, 2b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a position detection system that detects the position of a person or an object, and a management system that manages the movement status of a person or an object using the position detection system. The present invention relates to a system for detecting the position of a slave unit using the radio wave intensity at that time.

  Conventionally, many techniques have been proposed as a position detection system for detecting the position of a person or an object. Among them, a positioning system (GPS) using an orbital satellite is representative, and is widely used in a navigation system or the like for guiding a route to a driver of a vehicle (for example, see Patent Document 1).

  The position detection by GPS is useful not only for vehicles but also for detecting the position of packages being delivered or people who are moving, but in this method, the reception environment of GPS radio waves greatly affects positioning. There is a drawback of affecting. For this reason, in indoor locations where GPS radio waves do not reach or where there are many obstacles, problems such as temporary disabling or errors in positioning occur, and other detection methods may be used for position detection at those locations. Must be used.

  Therefore, for example, in Patent Document 2, as a system for managing the position of merchandise displayed in a store, a plurality of receivers (parent devices) are installed at predetermined positions and transmitters (child devices that transmit radio waves) A position detection system in which a machine is attached to a product has been proposed. This position detection system receives the radio waves transmitted from the handset at multiple base units and determines the distance between the base unit and the handset based on the received strength at that time, thereby identifying the position of the product Is configured to do.

JP-A-9-318381 JP 2002-236166 A

  However, in the position detection system described in Patent Document 2, the position of the product is obtained in order to identify the position of the product by forming a triangle between the slave unit attached to the product and the two master units. In this case, it is essential that the slave unit can communicate with at least two master units.

  For this reason, when installing the parent device, it is necessary to determine the installation location so that communication with two or more parent devices is always ensured regardless of the position of the product (slave device) placed in the store. In order to satisfy this condition, there is a problem that the interval between the parent devices must be narrowed, and a large number of parent devices are required. On the other hand, in order to meet the demand for cost reduction, it is desirable to reduce the number of installed base units. After all, the number of installed base units is reduced, but on the other hand, the detectable area is set narrow and a specific location is set. It is unavoidable to adopt an embodiment in which it is limited to use.

  Such problems occur not only when detecting the position of a product in a store, but also when detecting the position of a person indoors, etc., and the scale of a store increases or the range of movement of people increases. It becomes noticeable.

  Therefore, the present invention has been made in view of the problems in the prior art described above, and when detecting the position of a person or an object using radio wave intensity, without losing the detection accuracy of those positions, It is an object of the present invention to provide a position detection system and a management system that can reduce the number of installed master units and expand the detectable area.

  In order to achieve the above object, the present invention provides a plurality of master units that are installed at predetermined positions and transmit radio waves, and a plurality of slave units that receive radio waves from the plurality of master units and detect radio field intensity. A position detection system that determines the positions of the plurality of slave units by determining the distance between the master unit and the slave unit from the detected radio field intensity, wherein the plurality of slave units are between the slave units. A communication unit between slave units that transmits and receives radio waves; and a distance calculation unit that detects a radio wave intensity received by the communication unit between the slave units and calculates a distance between the slave units, and the position detection system includes the distance calculation The positions of the plurality of slave units are specified by interpolating the distances between the slave units calculated by the unit.

  According to the present invention, since the position of the slave unit is specified by interpolation using the distance between the slave units calculated by the distance calculation unit, the slave unit can directly receive radio waves from two or more master units. Even without this, the position of the handset can be specified, thereby reducing the number of base units installed and expanding the detectable area without losing the accuracy of detecting the position of people or objects. It becomes possible.

  In the position detection system, the plurality of slave units belong only to a first slave unit belonging to a radio wave transmission area of two or more master units and a radio wave transmission area of a single master unit. When the second slave unit exists, the position detection system calculates the position of the first slave unit, the distance from the first slave unit to the master unit, and the distance calculation unit. The position of the second slave unit can be specified using the distance between the slave units.

  The position detection system further includes a mobile base unit configured to be movable and transmitting radio waves, and the position detection system receives radio waves transmitted from the plurality of base units by the mobile base unit, and After specifying the position of the mobile master unit, the plurality of slave units receive radio waves transmitted from any of the plurality of master units and the mobile master unit, and specify the positions of the plurality of slave units Can do.

  According to the above configuration, it is possible to obtain the same effect as the expansion of the communication network area by adding another parent device around the fixedly installed parent device. The position of can be detected. In addition, by detecting the position of the mobile master unit, it is possible to detect the position of an object that moves with the owner or the mobile base unit. Therefore, the mobile base unit is one of the slave units. Can also be used together.

  In the position detection system, the plurality of slave units select, from among the plurality of master units, a master unit having the highest intensity of radio waves received from the plurality of master units as a transmission destination master unit can do.

  According to the above configuration, since the master unit suitable for communication is automatically selected and set on the slave unit side, the reliability of communication can be ensured even when the slave unit moves at high speed. As a result, it becomes possible to prevent the position of the slave unit from being unable to be specified due to a communication failure between the slave unit and the master unit.

  In the position detection system, the plurality of slave units include a time information generation unit that generates time information, and the time information generated by the time information generation unit can be transmitted to the master unit selected as the transmission destination. .

  In the position detection system, when the plurality of slave units includes a storage unit that cumulatively stores information indicating the time at which information is transmitted to the destination master unit, and the destination master unit is changed In addition, information indicating the time when the information is transmitted to the base unit before the change can be transmitted to the base unit after the change.

  In the position detection system, the frequency of specifying the positions of the plurality of slave units can be changed in accordance with the change in the position of the plurality of slave units. According to this configuration, the slave unit can be set to perform communication processing while being restricted when necessary, so that power consumption can be reduced.

  In addition, the present invention is a management system, wherein any one of the position detection systems described above is used to manage the movement status of a person or an object that moves accompanying the plurality of slave units.

  In the management system, it is possible to determine that a person or an object that moves with the plurality of slave units is present in a predetermined area, and to determine that the person or object is abnormal when the person or object deviates from the area.

  In the management system, it is possible to determine whether or not a person or an object moving with the plurality of slave units has entered or approached a predetermined restricted area and can perform an abnormality determination.

  As described above, according to the present invention, when detecting the position of a person or an object using radio wave intensity, the number of installed base units can be reduced or detected without impairing the detection accuracy of those positions. The area can be expanded.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an embodiment of a position detection system according to the present invention. This system 1 is roughly divided into a plurality of slave units 2a and 2b having a wireless communication function, and a plurality of stations that constantly transmit radio waves. Master units 3a to 3c and a central device 4 that specifies the positions of the slave units 2a and 2b based on information transmitted from the master units 3a to 3c. In FIG. 1, for convenience, the number of slave units is two, but three or more slave units may be provided. This also applies to the master unit, and four or more master units may be provided.

  The plurality of slave units 2a and 2b are small communication terminals that are built in accessories such as badges or attached to luggage or the like. These slave units 2a and 2b have the same configuration. As shown in FIG. 2, the radio receiver 21, inter-slave communication unit 22, radio intensity detector 23, information transmitter 24, communication destination selection Unit 25, timer 26, memory 27, and the like.

  The radio wave receiving unit 21 is a receiver for receiving radio waves transmitted from each of the parent devices 3a to 3c, and the inter-child device communication unit 22 is a wireless communication device for communicating with other child devices. . Since the communication between the slave units is direct communication between the terminals, the slave unit communication unit 22 is compliant with a short-range wireless communication standard such as ZigBee (registered trademark of Koninklijke Philips Electronics NV). It is preferable to use an apparatus.

  The radio wave intensity detection unit 23 is for detecting the intensity of the received radio wave and calculating the distance to the transmitter that has transmitted the radio wave. The radio wave intensity detection unit 23 calculates the distance from the parent devices 3 a to 3 c based on the radio wave intensity received by the radio wave reception unit 21, and other child devices based on the radio wave intensity received by the slave unit communication unit 22. And the distance is calculated.

  The information transmission unit 24 is a wireless communication device for transmitting information generated inside the slave units 2a and 2b to the master units 3a to 3c. In this information transmission part 24, the information produced | generated internally and the identification information attached | subjected to each subunit | mobile_unit 2a, 2b are included in a radio signal, and are transmitted. The information transmission unit 24 may be configured with a single communication device together with the radio wave reception unit 21, or may be configured with a communication device separate from the radio wave reception unit 21.

  The communication destination selection unit 25 selects a transmission destination of information to be transmitted from the information transmission unit 24 based on the radio wave intensity detected by the radio wave intensity detection unit 23. In the communication destination selection unit 25, when the radio wave reception unit 21 receives radio waves from the plurality of parent devices 3a to 3c, the communication device selection unit 25 selects the parent device having the highest reception intensity from the received radio waves, and selects the communication destination parent device. Set as.

  The timer 26 is for measuring the date and time. The memory 27 is a storage medium for storing various data, and includes a ROM and a RAM. In addition to the control program for controlling the operation of the slave unit, the memory 27 stores distance information calculated by the radio field intensity detector 23, time information measured by the timer 26, and the like.

  The plurality of master units 3a to 3c shown in FIG. 1 are radio wave transmitters that are fixedly installed at predetermined locations, and are installed, for example, in a room or near a wall of a passage. These master units 3a to 3c all have the same configuration. As shown in FIG. 2, the radio wave transmission unit 31, the information reception unit 32, the radio wave intensity detection unit 33, the inter-base unit communication unit 34, the memory 35, etc. Is provided.

  The radio wave transmission unit 31 is a transmission device for constantly transmitting radio waves. The radio wave transmission unit 31 modulates a radio wave signal according to the identification information attached to each of the parent devices 3a to 3c, and transmits the radio wave including information for identifying each parent device.

  The information receiving unit 32 is a receiving device for receiving information transmitted from the information transmitting unit 24 of the slave units 2a and 2b. In addition, the information receiving part 32 may be comprised by said radio wave transmission part 31 and a single communication apparatus, and may be comprised by a separate communication apparatus.

  The radio wave intensity detector 33 detects the intensity of the radio wave received by the information receiver 32 and calculates the distance from the slave units 2a and 2b that have transmitted the information. In the present embodiment, the distance between the slave unit and the master unit is calculated not only on the slave units 2a and 2b but also on the master units 3a to 3c side. This is because the distance is specified accurately. Therefore, when priority is given to simplification of the system configuration, the radio field intensity detection unit 33 on the base units 3a to 3c side may be omitted.

  The inter-base unit communication unit 34 is a communication device for communicating with other base units. The communication method between the parent devices may be either a wireless LAN or a wired LAN. For the communication device 34 between the parent devices, a communication device suitable for those communication methods can be used.

  The memory 35 is a storage medium for storing various data. The memory 35 stores control programs and setting data for controlling the operations of the parent devices 3a to 3c, data received from the child devices 2a and 2b, and the like. The

  The central device 4 shown in FIG. 1 is a control device that comprehensively controls the overall operation of the system 1. The central device 4 displays the CPU that executes the control program, and the positions of the parent device and the child device. A position calculation unit 41 is provided in addition to a display unit (not shown). The position calculation unit 41 collects distance information transmitted from the parent devices 3a to 3c and specifies the positions of the child devices 2a and 2b.

  Note that both the wireless LAN and the wired LAN can be used in the communication method between the central device 4 and the parent devices 3a to 3c, and the power line communication method described in JP-A-2004-336708 is used. You can also.

  Next, a position detection method using the position detection system 1 will be described. In this method, in order to detect the position of the slave units 2a and 2b, a process for setting the transmission destination of the information created in the slave units 2a and 2b is performed. First, referring to FIG. 2 and FIG. While explaining.

A. For example, when the handset 2a is located in the area A shown in FIG. 3, the handset 2a transmits both the radio wave 42 from the base unit 3a and the radio wave 43 from the base unit 3b. It is received by the receiving unit 21. At that time, the radio wave intensity detection unit 23 detects the reception intensity when the radio waves 42 and 43 are received, and determines which radio wave intensity is higher.

  Here, as shown in FIG. 3, since the distance to the parent device 3a is shorter than the distance to the parent device 3b and the radio wave 42 from the parent device 3a side becomes stronger, the communication destination selection unit 25 indicates that. And the communication destination selection unit 25 selects the parent device 3a as the information transmission destination.

  And the identification information of the subunit | mobile_unit 2a and the time information time-measured by the timer 26 are transmitted with respect to the main | base station 3a selected as a transmission destination. At the same time, the time information and the identification information (identification information of the parent device 3a) included in the radio wave transmitted from the parent device 3a are stored in the memory 27, and the date and time with which the parent device was communicated is added. Hold it.

  Thereafter, if the handset 2a moves to area B in FIG. 3, the handset 2a receives the radio wave 43 from the base unit 3b and the radio wave 45 from the base unit 3c. Here, since the distance to the base unit 3c is shortened, the radio wave intensity detection unit 23 detects that, and the communication destination selection unit 25 changes the information transmission destination from the base unit 3a to the base unit 3c. .

  And the identification information and time information of the subunit | mobile_unit 2a are transmitted with respect to the main | base station 3c similarly to the above. At this time, the time information stored in the memory 27 and the identification information of the parent device 3a are also transmitted, and the fact that the previous communication with the parent device 3a and the date and time at that time are transmitted to the parent device 3c. Thereby, not only the subunit | mobile_unit 2a itself but the main | base station side can grasp | ascertain the communication log | history of the subunit | mobile_unit 2a.

B. Position Detection Processing Subsequently, the position detection processing of the slave units 2a and 2b will be described with reference to FIGS. 2 and 4 to 7. In FIG. 4, the area C where the child device 2a is located is assumed to be within both the transmission area 46 of the parent device 3a and the transmission area 47 of the parent device 3b, and the area where the child device 2b is located. D is within the range of the transmission area 47 of the parent device 3b, but is outside the transmission area 46 of the parent device 3a. Here, “out of the range of the transmission area” includes not only the case where the radio wave does not reach the distance, but also the case where the radio wave is disturbed due to an obstacle or the like and the distance cannot be accurately determined.

B-1. In order to detect the position of the slave unit 2a, as shown in FIG. 6, first, the slave unit 3a, 3b is selected from the master units 3a, 3b according to the above-mentioned “A. Destination setting process”. A parent device for transmitting information created in 2a is set (step S1). Here, as shown in FIG. 5A, since the parent device 3a is closer to the parent device 3b, the parent device 3a is set as the transmission destination parent device.

  Next, the slave unit 2a receives radio waves transmitted from the master units 3a and 3b, and calculates a distance 52 from the slave unit 2a to the master unit 3a and a distance 53 from the slave unit 2a to the master unit 3b ( Steps S2, S3). Next, from the information transmitting unit 24 of the child device 2a to the information receiving unit 32 of the parent device 3a, the identification information of the child device 2a, the time information, the identification information of the parent devices 3a and 3b, and the information of the distances 52 and 53 are obtained. A radio signal including the signal is transmitted, and the distances 52 and 53 are transmitted to the base unit 3a (step S4). The time information, the identification information of the parent devices 3a and 3b, and the information of the distances 52 and 53 are also stored in the memory 27 of the child device 2a and are also held on the child device 2a side.

  Then, the distances 52 and 53 are transferred from the parent device 3a to the central device 4 (step S5), and the position calculation unit 41 (see FIG. 1) of the central device 4 calculates the position P3 of the child device 2a (step S6). . In the central device 4, the installation positions P1 and P2 of the parent devices 3a and 3b and the distance 51 between the parent device 3a and the parent device 3b are registered in advance, and the position calculation unit 41 stores the positions P1 and P2 and the distance. The position P3 of the subunit | mobile_unit 2a is pinpointed using 51-53.

B-2. In detecting the position of the slave unit 2b, as shown in FIG. 7, first, in each of the slave units 2a and 2b, the transmission destination of the information created internally is set (step S21, S22). Here, as shown in FIG. 5B, since the slave unit 2a is close to the master unit 3a and the slave unit 2b is close to the master unit 3b, the slave unit 2a sets the master unit 3a as a transmission destination, The machine 2b sets the parent machine 3b as a transmission destination.

  Thereafter, the process proceeds to the detection process of the position of the slave unit 2b. However, as shown in FIG. 4, the slave unit 2b only belongs to the transmission area 47 of the master unit 3b. Cannot receive the radio waves. For this reason, the distance between the subunit | mobile_unit 2b and the main | base station 3a cannot be calculated | required, but it becomes impossible to pinpoint the position of the subunit | mobile_unit 2b.

  Therefore, as shown in FIG. 7, first, the position of the child device 2a belonging to the transmission areas 46 and 47 of both the parent device 3a and the parent device 3b is specified (step S23). This process can be performed using the method shown in FIG. 6, and the distance 52 and the position P3 shown in FIG. 5B can be specified.

  Next, as shown in FIG. 7, the slave unit 2b receives radio waves from the master unit 3b, and calculates a distance 55 (see FIG. 5B) from the master unit 3b (step S24). Next, the identification information of the child device 2b, the identification information of the parent device 3b, and the information of the distance 55 are transmitted from the information transmission unit 24 of the child device 2b to the information receiving unit 32 of the parent device 3b (step S25). The information is transferred from the parent device 3b to the central device 4 (step S26).

  Next, between the slave units 2a and 2b, the slave units communicate with each other by the inter-slave unit communication unit 22, and the radio field strength detection unit 23 of the slave unit 2a detects the radio field strength at that time. And the distance 54 (refer FIG.5 (b)) between the subunit | mobile_unit 2a and the subunit | mobile_unit 2b is calculated, and the identification information of the subunit | mobile_unit 2a, 2b, time information, and the information of the distance 54 are calculated via the information transmission part 24. Is transmitted to the parent device 3a (step S27). Next, in the parent device 3a, the information transmitted from the child device 2a is transferred to the central device 4 (step S28), and the information on the distance 54 is transmitted to the central device 4.

  Thus, when the information on the distances 54 and 55 and the position P3 (FIG. 5B) is collected in the central device 4, the central device 4 in the central device 4 and the distance 51 between the parent device 3a and the parent device 3b, A square is formed using the distance 52 between the slave unit 2a and the master unit 3a and the information on the positions P1 and P2 of the master units 3a and 3b, and the position P4 of the slave unit 2b is specified (step S30).

  In principle, the detection of the positions of the slave units 2a and 2b is performed periodically. However, if no change is recognized in the positions of the slave units 2a and 2b as a result of the detection processing a plurality of times, the detection interval (communication interval) Is expanded step by step to reduce the frequency of detection. Then, if a change is recognized in the position of the subunit | mobile_unit 2a, 2b, a detection interval will be shortened in steps and detection frequency will be raised, and the position of the subunit | mobile_unit 2a, 2b will be tracked.

  Such an operation may be performed as a whole for the slave units 2a and 2b, or may be performed separately for the individual slave units 2a and 2b. By performing the above operation, the slave units 2a and 2b can be set to perform communication processing only when necessary, so that power consumption can be reduced. In particular, when the slave units 2a and 2b are operated by a battery, it is possible to suppress the consumption of the remaining amount of the battery, and it is possible to extend the continuous use time of the slave units 2a and 2b.

  As described above, in the present embodiment, among the plurality of slave units 2a and 2b, there exists a slave unit 2b that belongs only to the transmission area of the master unit 3b and does not belong to the transmission area of the master unit 3a. In addition, mutual communication is performed between the slave units to form a radio wave path from the slave unit 2b to the master unit 3a via the slave unit 2a. And while calculating | requiring the distance 54 between subunit | mobile_units from the intensity | strength of the received radio wave in the case of communication between subunit | mobile_units, and using the distance 54 interpolatingly, the part for the distance insufficient to pinpoint the position of the subunit | mobile_unit 2b is compensated. The position of the slave unit 2b is specified.

  For this reason, even if the subunit | mobile_unit 2b itself cannot receive the electromagnetic wave from the two main | base units 3a and 3b directly, the position of the subunit | mobile_unit 2b can be pinpointed, and, thereby, the detection accuracy of the position of a person or an object It is possible to reduce the number of installed master units and expand the detectable area without detracting from the situation.

  Moreover, in this Embodiment, since the distance 54 between subunit | mobile_units is transmitted to the center apparatus 4, the approach state of the subunit | mobile_unit 2a and the subunit | mobile_unit 2b can also be grasped | ascertained. For this reason, for example, “Mr. A is near Mr. B” or “Luggage A is placed near Luggage B” can be used to extract the landmark at the same time as detecting the position. , It becomes possible to improve convenience.

  In the present embodiment, since another child device 2a is used when specifying the position of the child device 2b, it is necessary that another child device exists around the child device whose position is to be detected. . For this reason, this position detection system 1 is suitable for use in a place where a plurality of people and objects are expected to move. Therefore, when using the position detection system 1, the position detection target area is compared with the concentration degree of a person or an object, and the position detection system 1 and the existing position detection system are used in different places. It is preferable.

  Next, another embodiment of the position detection system 1 according to the present invention will be described. In the previous embodiment, the case where both the base units 3a and 3b are fixedly installed at predetermined positions is illustrated. However, as shown in FIG. 8, the communication having the same function as the base units 3a and 3b. The apparatus can be provided in the accessory as in the case of the slave units 2a and 2b, or can be configured to change the installation position and be portable and function as the mobile master unit 61.

  However, the mobile master device 61 differs from the master devices 3a and 3b (hereinafter referred to as “fixed master device” in order to distinguish these master devices from the mobile master device 61) as people and objects move. Therefore, the position cannot be registered in the central device 4 in advance.

  Therefore, when using the mobile master device 61, first, the mobile master device 61 receives radio waves transmitted from the fixed master devices 3a and 3b, specifies the position of the mobile master device 61, and then The detection process of the position of the subunit | mobile_unit 2a, 2b is started.

  At that time, the position of the mobile master 61 is specified between the mobile master 61 and the fixed masters 3a and 3b by using the position detection method shown in FIG. 5 (a) and FIG. be able to. Further, the positions of the slave units 2a and 2b are two master units composed of one of the fixed master units 3a and 3b and the mobile master unit 61, and between these master units and the slave units 2a and 2b. Can be specified by using the position detection method shown in FIGS.

  According to the above embodiment, the same effect can be obtained as the expansion of the communication network area by adding another master unit around the fixed master units 3a and 3b. It becomes possible to detect the positions of the machines 2a and 2b. In addition, by detecting the position of the mobile master 61, it is possible to detect the position of the owner and the moving object accompanying the mobile master 61. It can also be used together as one of these.

  Next, application examples of the position detection system 1 will be described with reference to FIGS. 9 to 13.

  The application example shown in FIG. 9 is one in which the position detection system 1 is applied to a management system that counts visitor visits at department stores or the like. In this management system, a plurality of parent devices 71 to 73 are installed around the stores A to F, and the child devices 74 and 75 are distributed to customers in the form of badges. Then, while identifying the individual slave units 74 and 75, the position is appropriately detected, thereby managing which store visits which store at what time and what time.

  As described above, since the position detection system 1 can increase the installation interval between the parent machines, the number of installed parent machines can be reduced in the present management system, resulting in a significant increase in system cost. Reduction can be achieved.

  In this management system, for example, when two customers who have the child devices 74 and 75 stop at the stores A to F, the child devices 74 and 75 are communicated between the parent devices 71 and 72 and the child devices 74 and 75. Is detected, and the time at which the slaves 74 and 75 stop at the stores A to F is sequentially stored in the memory 27 (see FIG. 2). For this reason, if those information is transmitted to the main units 71 to 73 and transferred to the central device 4 (see FIG. 1), not only the store where each visitor stopped, but also the time when the store stopped, You can also know the time you stayed and the number of stops.

  Since the management system for the visitor's excursion situation is not for searching for the location of the visitor, it is not necessary to transmit the position and time to the central device 4 each time the visitor moves. For this reason, some of the large number of parent devices (for example, the parent device installed in the elevator hall) are determined as the parent device for data aggregation, and when the child devices 74 and 75 approach the parent device, The distance information and time information stored in the memory 27 may be transmitted collectively.

  The application example shown in FIG. 10 is one in which the position detection system 1 is applied to a management system that manages the expiration date of products displayed in a grocery store or the like. In this management system, the master units 71 and 72 are installed at predetermined positions in the store, and the slave units 74 and 75 are attached to the product in the form of a tag or the like, so that the product position (display location) and time information are displayed. to manage.

  In this management system, the expiry date for each product is set in advance, the information on the expiry date is compared with the time after the product has been displayed, Detect the presence or absence of goods. In addition, in this management system, when a product whose expiration date is approaching or a product whose expiration date is close is detected, it is determined as abnormal and notified to the manager, etc. It is not necessary to perform the operation on the device 4 (see FIG. 1) side, and each parent device 71 and 72 can also perform the operation.

  That is, information on the expiration date is also set on the parent devices 71 and 72 side by transmitting the information on the expiration date from the central device 4 to the parent devices 71 and 72. The time information transmitted from the machines 74 and 75 is compared, and the presence or absence of an abnormality is determined. When an abnormality is recognized, an abnormality determination signal is transmitted from the parent device to the central device 4, and the central device 4 centrally manages the presence or absence of abnormality for each product. According to this configuration, it is not necessary to centrally manage the display time for all commodities in the central device 4, so that the load on the central device 4 side can be reduced.

  Although the display location may be changed in the middle of the display of the product, in the present embodiment, the past time information and the like are accumulated in the memory 27 of the slave units 71 and 72. Later, information exchanged with the previous base unit is transmitted to the new base unit. For this reason, even if the display location is changed, the time information and the like are not lost, and are inherited by the changed master unit. Therefore, the display time of the product can be accurately grasped, and the expiration date can be appropriately managed.

  In the application example shown in FIG. 11, the position detection system 1 is applied to a management system that manages a gathering state of tourists on a sightseeing trip using a bus. In this management system, while the master unit 71 is installed on the bus, it is determined whether or not the tourists who have distributed the slave units 74 and 75 are gathered in the gathering area within a predetermined time while carrying the master unit 72 to the passenger. To do.

  In the case of this system, the positions of the buses and the passengers are indefinite, so the positions of the slave units 74 and 75 (the positions of the tourists) are relative to the bus and the passengers (for example, in which direction from the bus How many meters away, etc.). Further, the base unit 72 carried by the crew is the mobile base unit 61 shown in FIG.

  In this management system, when the slave units 2a and 2b exist in the radio wave transmission area of the master units 71 and 72, the tourists are detected in the gathering area after detecting the positions of the slave units 2a and 2b. It can be judged that they are gathered. At this time, the information indicating the gathering status of tourists may be transmitted to the master device 71 on the bus side or may be transmitted to the master device 72 on the passenger side.

  On the other hand, when the slave units 2a and 2b deviate from the radio wave transmission area of the master units 71 and 72 and no information is transmitted from the slave units 2a and 2b to the master units 71 and 72, the master unit 71, In 72, it can be determined that the tourist who owns the handset 2a, 2b has not come to the meeting place and is abnormal.

  In the application example shown in FIG. 12, the position detection system 1 is applied to a security system that restricts entry into a specific place. In this system, parent devices 71 and 72 are provided in the vicinity of a medicine cabinet, an executive room, etc., and a radio wave path is formed between these parent devices 71 and 72 and a plurality of child devices 74 and 75, and the child devices 74 and 75 are provided. The position of is detected.

  In the system described above, if a group of persons permitted to enter a chemical warehouse or the like is registered in advance, the person's access to the chemical warehouse or the like can be restricted. For example, if the owner of the handset 74 does not belong to the above group and intrudes or approaches the area near the medicine cabinet in that state, immediately detect it and take measures such as alerting or warning. Can do.

  The application example shown in FIG. 13 is one in which the position detection system 1 is applied to a system that manages the location of a person in a school or the like. In this system, the parent devices 71 and 72 are provided in a specific place in the school or school route, and the child's position can be managed by having the child devices 74 and 75 held by the child. At this time, for example, by monitoring the position of the child against the time, it can be used for management of attendance of classes, etc., and by monitoring whether it has moved to the meeting place within a predetermined time, It can also be used for a child's call.

  Furthermore, the present position detection system 1 can be applied to managing the storage location and loading / unloading of luggage in a distribution warehouse, and also to managing equipment in an office building. Can be widely used in the field.

  The embodiment of the present invention has been described above, but the present invention is not limited to the above-described configuration, and various modifications can be made within the scope of the invention described in the claims.

  For example, in the above embodiment, the position calculation unit 41 is provided in the central device 4, but the position calculation unit 41 is provided in the parent devices 3a to 3c, and the parent devices 3a to 3c specify the positions of the child devices 2a and 2b. May be. However, in this case, since information such as distance must be collected in one place, it is necessary to determine in advance to which parent device the information is collected.

1 is an overall configuration diagram showing an embodiment of a position detection system according to the present invention. It is a block diagram which shows the functional structure of a main | base station and a subunit | mobile_unit. It is a figure explaining the setting process of a communication destination. It is a schematic diagram which shows an example of the position of a some subunit | mobile_unit. It is a figure explaining the position detection method using a position detection system. It is a flowchart explaining a position detection process. It is a flowchart explaining a position detection process. It is a whole block diagram which shows other embodiment of the position detection system concerning this invention. It is a figure which shows the example of application of the position detection system concerning this invention. It is a figure which shows the example of application of the position detection system concerning this invention. It is a figure which shows the example of application of the position detection system concerning this invention. It is a figure which shows the example of application of the position detection system concerning this invention. It is a figure which shows the example of application of the position detection system concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Position detection system 2 (2a, 2b) Slave | mobile_unit 3 (3a-3c) Master | base_unit 4 Central apparatus 21 Radio wave receiving part 22 Inter-slave communication part 23 Radio wave intensity detection part 24 Information transmission part 25 Communication destination selection part 26 Timer 27 Memory 31 Radio wave transmission unit 32 Information reception unit 33 Radio wave intensity detection unit 34 Inter-base communication unit 35 Memory 41 Position calculation units 42-45 Radio wave 46, 47 Radio wave transmission area 51-55 Distance 61 Mobile base units 71-73 Machine 74, 75 Child machine

Claims (10)

A plurality of master units that are installed at predetermined positions and transmit radio waves, and a plurality of slave units that receive radio waves from the plurality of master units and detect radio field intensity, and from the detected radio field intensity A position detection system for determining positions of the plurality of slave units by obtaining a distance between the master unit and the slave units,
The plurality of slave units includes a slave unit communication unit that transmits and receives radio waves between the slave units, and a distance calculation unit that detects a radio wave intensity received by the slave unit communication unit and calculates a distance between the slave units. Prepared,
The position detection system is characterized in that the positions of the plurality of slave units are specified by interpolating the distances between the slave units calculated by the distance calculation unit. In the plurality of slave units, a first slave unit belonging to the radio wave transmission area of the two or more master units, and a second slave unit belonging only to the radio wave transmission area of the single master unit, When
The position detection system uses the position of the first slave unit, the distance from the first slave unit to the master unit, and the distance between slave units calculated by the distance calculation unit. The position detection system according to claim 1, wherein the position of the second slave unit is specified. It is configured to be movable, and further comprises a mobile master unit that transmits radio waves,
The position detection system receives radio waves transmitted from the plurality of parent devices by the mobile parent device and specifies the position of the mobile parent device, and then determines one of the plurality of parent devices and the mobile parent device. The position detection system according to claim 1, wherein the plurality of slave units receive radio waves transmitted from the plurality of slave units and specify the positions of the plurality of slave units.   The plurality of slave units select a master unit having the highest intensity of radio waves received from the plurality of master units among the plurality of master units as a destination master unit for transmitting information. The position detection system according to claim 1, 2 or 3. The plurality of slave units includes a time information generation unit that generates time information,
The position detection system according to claim 4, wherein the time information generated by the time information generation unit is transmitted to the parent device selected as the transmission destination. The plurality of slave units includes a storage unit that cumulatively stores information indicating a time at which information is transmitted to the destination master unit,
6. The position detection system according to claim 5, wherein, when the transmission destination parent device is changed, information indicating a time at which information is transmitted to the parent device before the change is transmitted to the changed parent device. .   The position detection system according to claim 1, wherein the frequency of specifying the positions of the plurality of slave units is changed in accordance with a change in the position of the plurality of slave units.   A management system for managing a movement status of a person or an object moving with the plurality of slave units using the position detection system according to any one of claims 1 to 7.   9. The method according to claim 8, wherein when a person or an object moving with the plurality of slaves is present in a predetermined area, it is determined as normal, and when the person or object deviates from the area, it is determined as abnormal. The management system described.   The management system according to claim 8, wherein a determination is made as to whether or not a person or an object moving with the plurality of slave units has entered or approached a predetermined restricted area, and performs an abnormality determination.

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