JP2009231868A - Mobile terminal, communication system, and control method of mobile terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-reliability mobile terminal which is reduced in power consumption to save electric power and decreases a probability of a connection error, to provide a communication system, and to provide a control method of the mobile terminal. <P>SOLUTION: The mobile terminal includes: a GPS unit 33 which acquires current position information; an RFID tag 10 which selectively alternates between a reader writer mode for wireless communication with an external RFID tag and a tag mode for wireless communication with an external tag reader device to communicate; a reception power detector 15 which detects the reception power level of a reception signal when the RFID tag 10 communicates with the external RFID in the reader writer mode; and a control unit 25 and an RFID control unit 19 that controls the detecting operation of the external tag reader device based upon a reception power level corresponding to the current position information acquired by the GPS unit 33 by reference to history information wherein position information on a position where the reception power level of the external RFID tag is previously measured and the reception power level measured at the position are stored while made to correspond to each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a portable terminal, a communication system, and a method for controlling the portable terminal, and more particularly, to a portable terminal including an active RFID tag or tag reader / writer device, a communication system, and a method for controlling the portable terminal.

  As a portable terminal provided with a conventional RFID (Radio Frequency IDentification), there is one described in Patent Document 1, for example. RFID refers to a chip that also has an antenna for communicating with a tag in which unique information is written, and exchanges and writes information by short-range wireless communication using electromagnetic fields or radio waves. is there.

An active tag has a power supply circuit in the tag itself, and can transmit a signal as a reader / writer without receiving a magnetic field and a command from an opposing reader / writer device. Can communicate far away. In addition to the reader / writer device, the active tag can also communicate between the active tags on a peer-to-peer basis. In recent years, RFID reader / writer devices have also been miniaturized to a size that can be mounted on mobile phones. The theoretical value of the communication distance is also said that passive tags can communicate at 10 m when the transmission power at the 50 ohm end is 1 W, and active tags can communicate at 100 m at a transmission power of 50 ohm end at 1 mW. When mounting as a device, the antenna characteristics are such that the communicable distance is smaller than the theoretical value due to factors such as the shape of the housing and mounting conditions, or electromagnetic waves are intentionally radiated only to a short distance to prevent unnecessary radiation. There are many specifications.
JP 2006-14355 A JP 2005-311810 A JP 2007-201799 A Klaus Finkenzeller, Translated by Software Engineering Laboratory, "RFID Handbook Principle and Application of Contactless IC Card", First Edition, Nikkan Kogyo Shimbun, February 2001, p. 168-169

  However, the prior art described in the above literature has room for improvement in the following points.

  When the RFID tag and the reader / writer device communicate with each other, the reader / writer device side is designed to specify the magnetic field generation time and the rest time. Therefore, the length of the time is often designed with a fixed value and is consumed. There were still scenes where the settings were not necessarily optimal in terms of power and connection rate.

  In the case of a portable terminal having an active tag and a reader / writer device, the RFID tag side also has a built-in power supply. However, the time during the detection operation (the magnetic field is generated on the reader device side), and the detection time The pause time between them could not be optimized dynamically for each scene. Therefore, there is a problem due to the fact that the tag operates at the same fixed value detection time and rest time regardless of whether the received power level of the tag is low or high, even when the tag is in the reader / writer mode.

  Specifically, in a place where the received power of the tag of the mobile terminal is high, even when the magnetic field generation time when operating in the reader / writer mode, that is, when the pause time between detection times can be set longer, the fixed value This leads to wasted power consumption. In addition, in a place where the received power of the tag is low, if the detection time is a fixed value, the probability of a connection error may increase due to the short time.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a highly reliable portable terminal, communication system, and portable device that reduce power consumption by reducing power consumption and reducing the probability of connection errors. It is to provide a terminal control method.

The mobile terminal of the present invention includes an acquisition means for acquiring current position information;
A communication means for selectively switching between a reader / writer mode for performing wireless communication with an external RFID tag and a tag mode for performing wireless communication with an external tag reader device;
Detecting means for detecting a received power level of a received signal when the communication means communicates with the external RFID tag in the reader / writer mode;
The current information obtained by the obtaining unit is obtained by referring to history information in which the position information of the position where the received power level of the external RFID tag is measured in advance and the received power level measured at the position are stored in association with each other. Control means for controlling a detection operation of the external tag reader device based on the received power level corresponding to the position information.

The communication system of the present invention includes a portable terminal of the present invention,
A communication system comprising a server connected to the mobile terminal via a network,
The server
History storage means for storing the history information;
Transmitting means for transmitting the history information stored in the history storage means to the portable terminal via the network.

The mobile terminal control method of the present invention includes an acquisition unit that acquires current position information;
A communication unit for selectively switching between a reader / writer mode for performing wireless communication with an external RFID tag and a tag mode for performing wireless communication with an external tag reader device;
A detection unit that detects a reception power level of a received signal when the communication unit communicates with the external RFID tag in the reader / writer mode, and a method for controlling a detection operation of the external tag reader device in a portable terminal. And
The current information acquired by the acquisition unit with reference to the position information of the position where the received power level of the external RFID tag is measured in advance and the history information stored in association with the received power level measured at the position. Based on the received power level corresponding to the position information, the detection operation of the external tag reader device is controlled.

  It should be noted that any combination of the above-described constituent elements and a conversion of the expression of the present invention between a method, an apparatus, a system, a recording medium, a computer program, etc. are also effective as an aspect of the present invention.

  The various components of the present invention do not necessarily have to be independent of each other. A plurality of components are formed as a single member, and a single component is formed of a plurality of members. It may be that a certain component is a part of another component, a part of a certain component overlaps with a part of another component, or the like.

  Moreover, although the several procedure is described in order in the control method and computer program of this invention, the order of the description does not limit the order which performs a several procedure. For this reason, when implementing the control method and computer program of this invention, the order of the several procedure can be changed in the range which does not interfere in content.

  Further, the control method and the plurality of procedures of the computer program of the present invention are not limited to being executed at different timings. For this reason, another procedure may occur during the execution of a certain procedure, or some or all of the execution timing of a certain procedure and the execution timing of another procedure may overlap.

  According to the present invention, a highly reliable portable terminal, a communication system, and a method of controlling the portable terminal that reduce power consumption by reducing power consumption and reduce the probability of connection error are provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

(First embodiment)
FIG. 1 is a block diagram showing a configuration of a mobile terminal according to an embodiment of the present invention.

  The mobile terminal (mobile phone 1) of this embodiment includes an acquisition unit (Global Positioning System (GPS) unit 33) that acquires current position information, a reader / writer mode that performs wireless communication with an external RFID tag (not shown), and A communication unit (RFID antenna 11, RFID tag 10) for selectively switching a tag mode for wireless communication with an external tag reader device (not shown), and when the communication unit communicates with an external RFID tag in the reader / writer mode Corresponds between the detection unit (received power detector 15) for detecting the received power level of the received signal, the position information of the position where the received power level of the external RFID tag is measured in advance, and the received power level measured at the position The external tag reader device is detected based on the received power level corresponding to the current position information acquired by the acquisition unit with reference to the history information attached and stored. And a control unit (control unit 25 and RFID control unit 19) for controlling the operation.

  In the mobile terminal (cell phone 1) of the present embodiment, the received power level detected by the detection unit (reception power detector 15) at the current position is associated with the position information acquired by the acquisition unit (GPS unit 33) and recorded as a history. The information processing apparatus further includes a storage unit 27 that stores information, and the control unit 25 refers to the history information stored in the storage unit 27 and controls the detection operation of the external tag reader device.

  The mobile terminal of this embodiment is a terminal that can be connected to a mobile communication network (not shown) via a base station (not shown). For example, a mobile phone, PHS (Personal Handyphone System), PDA (Personal Digital Assistants) And game consoles. Alternatively, the mobile terminal may be a mobile phone that can be connected to a wireless LAN network (not shown) or various mobile information terminals. In the present embodiment, the mobile phone 1 is described as an example. In the following drawings, the configuration of parts not related to the essence of the present invention is omitted and is not shown.

  Each component of the cellular phone 1 includes an arbitrary computer CPU, memory, a program for realizing the components shown in the figure loaded in the memory, a storage unit such as a hard disk for storing the program, and a network connection interface. It is realized by any combination of hardware and software. It will be understood by those skilled in the art that there are various modifications to the implementation method and apparatus. Each drawing described below shows a functional unit block, not a hardware unit configuration.

  Specifically, the mobile phone 1 has an active RFID tag 10 (hereinafter simply referred to as “RFID tag”) and has an RFID communication function. The RFID tag 10 includes an RFID antenna 11, a regulator 13, a received power detector 15, a modulator / demodulator 17, an RFID control unit 19, a comparison / determination unit 21, and an RFID storage unit 23. The cellular phone 1 further includes a control unit 25, a storage unit 27, a cellular phone radio unit 29, a cellular phone antenna 31, a GPS unit 33, and a GPS antenna 35.

  However, in the present embodiment of FIG. 1, this indicates a circuit that realizes a function as a standard active tag and tag reader / writer, and many other circuit configurations can be considered. Since there is no feature in the circuit configuration, many examples are not described.

  The RFID tag 10 functions as a tag or a tag reader / writer. As described later, the operation mode is selectively switched between the tag mode and the reader / writer mode, and an external reader / writer device or Communicate with external tags. The regulator 13 controls the voltage and supplies a constant value to the circuit. The received power detector 15 detects the received signal from the counterpart tag and causes the RFID tag 10 to perform a detection operation. As shown in FIG. 4A, similarly to the magnetic field generation period in a standard tag reader / writer device, the received power detector 15 generates a magnetic field for a predetermined magnetic field generation time, here 50 msec, and performs a detection operation. The operation of stopping the magnetic field is periodically repeated for a predetermined pause time during the magnetic field generation time, here 3 msec, and the RF signal from the counterpart tag is detected. The reception power detector 15 detects the reception power level of the detected RF signal.

  Returning to FIG. 1, the modulator / demodulator 17 modulates and demodulates the RF signal. The RFID control unit 19 controls the entire circuit of the RFID tag 10 together with each element of the RFID tag 10. The RFID control unit 19 also performs control to selectively switch the operation mode of the RFID tag 10 between a reader / writer mode for wireless communication with an external tag and a tag mode for wireless communication with an external reader / writer device. The operation mode can be switched by the user of the mobile phone 1 instructing an operation, or can be automatically switched according to an external situation.

  The comparison determination unit 21 determines whether the received power level received from the external tag when the RFID tag 10 is in the reader / writer mode and whether the past received power level is higher or lower than a set threshold value. Each threshold value is stored in the storage unit 27 described later. Moreover, it can also be set as the structure in which the user of the mobile telephone 1 can change a setting. The past received power level is stored in the storage unit 27. For example, the comparison determination unit 21 can acquire the past received power level via the control unit 25 and the RFID control unit 19. Alternatively, the comparison determination unit 21 may be included in a part of the RFID control unit 19 or the control unit 25 described later. The RFID storage unit 23 stores data written to the RFID tag 10 and ID information of the RFID tag 10.

  The control unit 25 controls the entire apparatus together with each element of the mobile phone 1. It is also used for storing the control unit of the cellular phone 1 main body and the tag reception history. The storage unit 27 includes a ROM (Read Only Memory) and a RAM (Random Access Memory), and includes an area for storing a program for controlling the mobile phone 1 and various data, a work area used by the program, and the like. The mobile phone radio unit 29 is a functional block for communicating with a mobile phone network (not shown) via the mobile phone antenna 31. The GPS unit 33 is one of means for acquiring position information of a location where the mobile phone 1 is currently located from the GPS (not shown) via the GPS antenna 35.

  In addition, the control program of the mobile terminal (mobile phone 1) according to the embodiment of the present invention includes an acquisition unit (GPS unit 33) that acquires current position information, a reader / writer mode that performs wireless communication with an external RFID tag, and A communication unit (RFID tag 10) for selectively switching a tag mode for performing wireless communication with an external tag reader device, and a received signal when the communication unit (RFID tag 10) communicates with an external RFID tag in the reader / writer mode. A program for controlling a mobile phone 1 having a detection unit (reception power detector 15) for detecting a reception power level, and a computer (control unit 25 or RFID control unit 19) is connected to an external RFID tag History information in which the position information of the position where the received power level is measured in advance and the received power level measured at the position are stored in association with each other Reference, based on the reception power level acquisition unit (GPS unit 33) corresponding to the obtained current position information is a control program for functioning as a means of controlling the detection operation of the external tag reader device.

  In the present embodiment, it is assumed that the position of the external RFID tag reader / writer device or the external active tag (not shown) is a fixed position, and it is necessary to know the relative positional relationship with the mobile phone 1 in advance. System configuration that can be recognized or acquired by GPS, or that can be acquired from GPS or a mobile phone network. In this embodiment, since it is a fixed position, information (base station ID and the like) registered in the server is used, so detailed latitude / longitude information by GPS is not necessary. In the present embodiment, the external RFID tag reader / writer device or the external active tag is assumed to be a fixed position. However, the present invention is not limited to this, and the external RFID tag reader / writer device or the external active tag Even when both of the mobile phones 1 move, it is also possible to collect both the positional information and the history information of the reception level, and refer to and compare the history information of both.

  In the present embodiment, the control unit (the control unit 25 and the RFID control unit 19) receives the received power level of the received signal detected by the received power detector 15 from the RFID control unit 19, and the position information acquired by the GPS unit 33, That is, the latitude / longitude information is associated and stored in the storage unit 27 as the history information 37 of FIG. As illustrated in FIG. 2, the history information 37 stores position information (latitude and longitude) in association with the acquisition date and time of the position information and the received power level at that time. Furthermore, the history information 37 may further store the result of comparison of the received power level with the threshold by the comparison determination unit 21 as a flag indicating whether the received power level is equal to or lower than the threshold.

  Specifically, in the mobile terminal (mobile phone 1) of the present embodiment, the history information 37 is referred to, and based on the received power level in the history information 37 corresponding to the current position information, the detection unit (received power detector 15). ) Further includes a first threshold value determination unit (comparison determination unit 21) that determines whether or not the received power level at the current position detected is equal to or lower than the first threshold value, and the control unit (control unit 25 and RFID control unit 19) includes When the first threshold determination unit (comparison determination unit 21) determines that the received power level at the current position is equal to or lower than the first threshold, the detection time for performing the detection operation of the external tag reader device (time for generating a magnetic field) Is set to a predetermined detection time (for example, a minimum value), and a stop time between detection times for causing the communication unit (RFID tag 10) to stop the detection operation is set to a predetermined stop time (for example, a minimum value). When the first threshold value determination unit (comparison determination unit 21) determines that the received power level at the current position is not less than or equal to the first threshold value, the pause time is set longer, and the set detection time and pause are set. The communication unit (RFID tag 10) is controlled according to time. Here, the pause time is longer than the current set value and can be set and changed in steps up to a predetermined maximum value.

  The control unit (the control unit 25 and the RFID control unit 19) determines the detection time when the first threshold value determination unit (comparison determination unit 21) determines that the received power level at the current position is not less than or equal to the first threshold value. The minimum value (for example, a predetermined detection time) is set.

  Further, in the mobile terminal (mobile phone 1), the current position detected by the detection unit (received power detector 15) based on the received power level in the history information 37 corresponding to the current position information with reference to the history information 37. And a second threshold value determination unit (comparison determination unit 21) for determining whether or not the received power level is equal to or higher than the second threshold value. The control unit (control unit 25 and RFID control unit 19) includes a second threshold value determination unit. When the (comparison / determination unit 21) determines that the received power level at the current position is greater than or equal to the second threshold value, it sets a predetermined detection time (for example, the minimum value) for performing the detection operation of the external tag reader device, A predetermined pause time (for example, a minimum value) between detection times for stopping the detection operation is set, and the received power level at the current position is less than or equal to the second threshold value by the second threshold value determination unit (comparison determination unit 21). Not equal when it is determined to set a longer detection time, according to the set detection time and the pause time, it controls the communication unit (RFID tag 10). Here, the detection time is longer than the current set value, and can be set and changed in steps up to a predetermined maximum value.

  Further, in the mobile terminal (mobile phone 1), the control unit (the control unit 25 and the RFID control unit 19) causes the second threshold determination unit (comparison determination unit 21) to determine that the received power level at the current position is not equal to or higher than the second threshold. When it is determined, the pause time is set shorter than the predetermined pause time. Here, the pause time is shorter than the current set value, and can be set and changed in steps up to a predetermined minimum value.

  Further, the control unit 25 communicates with the server of the mobile phone network 40 via the mobile phone antenna 31 and acquires the base station ID of the area where the own device exists. Further, the control unit 25 communicates with the server of the mobile phone network 40 via the mobile phone antenna 31 and acquires the base station ID of the area where the nearest RFID tag reader / writer device 50 exists. Alternatively, the control unit 25 communicates with the server of the mobile phone network 40 via the mobile phone antenna 31 and inquires whether the server exists within the communicable area of the RFID tag reader / writer device 50 nearest to the server. Get the result.

  The operation of the mobile phone 1 of the present embodiment configured as described above will be described below. FIG. 3 is a diagram illustrating state transition of the mobile phone 1 according to the present embodiment. FIG. 4 is a diagram showing the magnetic field generation time and the rest time in the magnetic field generation cycle of the mobile phone 1 of the present embodiment. FIG. 5 is a flowchart showing an example of the operation of the mobile phone 1 of the present embodiment. Hereinafter, description will be made with reference to FIGS.

  In step S0 in FIG. 3, the mobile phone 1, that is, the RFID tag 10 is not in the area of the operating magnetic field of the counterpart reader / writer device (not shown) and accepts a command sent from the counterpart reader / writer device. This state is referred to as a “power off” state. Step S1 is a case where the RFID tag 10 is in the region of the operating magnetic field of the counterpart reader / writer device, and is an operable state in which a command from the counterpart reader / writer device can be received, and is set to “Ready”. Actually, there is a state in which other command inputs are restricted after “Ready”, but the description is omitted because it is not directly related to the present invention.

  In this embodiment, the reader / talk / first method is adopted as a basic transmission method of communication of the RFID tag 10, an activation command is sent from the reader / writer device on the other side to the RFID tag 10, and the activation is performed. The RFID tag 10 receives the command and responds to start communication.

  In the case of a full-duplex transponder and a reader / writer device, the RFID tag 10 that has received a command from the magnetic field returns to the reader / writer device on the other side at the same time. In this embodiment, the reception detection possible time, that is, the magnetic field generation time is set according to the standard specification, and as shown in FIG. 4A, the magnetic field generation time 50 msec and the pause time 3 msec are the initial values. The magnetic field generation time can be extended to a maximum of 100 msec and the pause time can be extended to 30 msec (see Non-Patent Document 1).

  FIG. 5 is a flowchart showing the operation when the received power level history information 37 is stored in the RFID tag 10 on the mobile phone 1 side of the present embodiment. As a supplementary explanatory diagram at this time, as shown in FIG. 6, there are a cell A and a cell B connected by a mobile phone network 40, and the mobile phone 1 of the user A exists in the cell A. As described above, the mobile phone 1 includes the RFID tag 10 and the GPS unit 33. On the other hand, in the cell B, it is assumed that an RFID tag reader / writer device 50 (shown as “RFID tag reader” in the drawing) is present as a counterpart device. In the present embodiment, the latitude / longitude information of the RFID tag reader / writer device 50 is not acquired by the mobile phone 1 of the present embodiment, and the base station ID is used as described above. Note that the operations shown in the flowchart of FIG. 5 are always repeated.

  First, in the state of step S10 in FIG. 5, as shown in FIG. 6, the mobile phone 1 of user A is out of the communicable range of the RFID tag reader / writer device 50 and does not belong to the RFID tag reader / writer device 50. It shall be in A. In step S <b> 11, the mobile phone 1 of the user A obtains base station ID information of a cell (here, cell A) in the mobile phone network 40 from a server (not shown) of the mobile phone network 40. Specifically, the control unit 25 (FIG. 1) causes the mobile phone radio unit 29 (FIG. 1) to communicate with the server of the mobile phone network 40 via the mobile phone antenna 31 (FIG. 1), and the base station Get ID information.

  In step S13, the mobile phone 1 of the user A further obtains the base station ID of the mobile phone network 40 where the counterpart RFID tag reader / writer device 50 exists by inquiring the server, and obtains the base of the RFID tag reader / writer device 50. Based on the station ID and the base station ID of the own device acquired in step S11, the own device exists in the same area (cell B) as the cell of the mobile phone network 40 where the corresponding RFID tag reader / writer device 50 exists. Determine whether you are doing. Alternatively, the mobile phone 1 may query the server of the mobile phone network 40 and obtain the result. Here, the RFID tag communicable area 44 of the counterpart RFID tag reader / writer device 50 is narrower than the cell B of the mobile phone network 40 where the RFID tag reader / writer device 50 exists, and is included in the range of the cell B. To do.

  Note that the RFID tag reader / writer device 50 is fixed when the RFID tag communicable area 44 of the RFID tag reader / writer device 50 extends over two cells of the cellular phone network 40, for example, the cell A and the cell B. At this time, it is assumed that the adjacent cell that does not belong to the RFID tag reader / writer device 50 is also a target cell for storing data of the reception history. Then, when the RFID tag 10 of the mobile phone 1 and the RFID tag reader / writer device 50 can communicate with each other in an adjacent cell that does not belong to the RFID tag reader / writer device 50, it is additionally registered as a new target cell for storing the reception history data. It shall be possible.

  If it is determined in step S13 in FIG. 5 that the RFID tag reader / writer device 50 is in the same cell (that is, cell B) (Yes in S13), the RFID tag 10 shifts to a state in which a detection operation can be started. In step S15, the GPS unit 33 (FIG. 1) of the mobile phone 1 acquires the current position information (latitude and longitude) from the GPS 42 (FIG. 6). In step S <b> 17, the location information (latitude and longitude) of the current location acquired from the GPS 42 is stored as history information 37 in the storage unit 27 (FIG. 1) of the mobile phone 1.

  In step S19, the RFID tag reader / writer device 50 starts detection and measures. In step S23, the received power level obtained by measuring in step S19 is stored as history information 37 in the storage unit 27 of the mobile phone 1 in association with the position information (latitude and longitude) of the GPS 42 stored in step S17, and the process is performed. finish.

  As a supplementary explanation, at the stage of step S19, the operation is performed assuming that the history information 37 of the received power level of the RFID tag reader / writer device 50 has not yet been stored. However, when the history information 37 already exists. The operation of referring to the history information 37 enters step S19. This will be described later with reference to the flowchart of FIG.

  On the other hand, when the mobile phone 1 of the user A does not exist in the cell of the mobile phone network 40 where the counterpart RFID tag reader / writer device 50 exists (No in S13: in cell A) in step S13 of FIG. 6, when the mobile phone 1 of the user A is in the cell A of the mobile phone network 40, the process proceeds to step S25, and the RFID tag 10 does not start the detection operation of the received signal of the RFID tag reader / writer device 50. In step S27, the cellular phone 1 or the cellular phone network 40 does not store the history information 37 of the received power level of the RFID tag 10, and ends the process.

  Thus, the history at each position of the history information 37 stored in the storage unit 27 is schematically shown in FIG. Here, the locations indicated by the crosses of history A, history B, history C, and history D indicate that the received power level is below the threshold and is difficult to perform the receiving operation normally. The locations indicated by ● in the history E, history F, and history G indicate that the reception level is equal to or higher than the threshold value and that the reception operation can be performed normally.

  Next, an operation when the mobile phone 1 moves into the RFID tag communicable area 44 of the RFID tag reader / writer device 50 will be described. FIG. 8 is a flowchart showing an example of the operation of the mobile phone 1 of the user A that has moved into the RFID tag communicable area 44 of the RFID tag reader / writer device 50. Hereinafter, description will be made with reference to FIGS. 1, 4, 7, and 8. At this time, it is assumed that the history information 37 is stored in the storage unit 27 of the mobile phone 1 of the user A.

  A method for controlling a mobile terminal (mobile phone 1 in FIG. 1) according to an embodiment of the present invention includes an acquisition unit that acquires current position information, a reader / writer mode that performs wireless communication with an external RFID tag, and an external tag reader device. The communication unit that selectively switches the tag mode for performing wireless communication and the communication unit (RFID tag 10 in FIG. 1) detect the received power level of the received signal when communicating with the external RFID tag in the reader / writer mode. And a detection unit for controlling a detection operation of an external tag reader device in a mobile terminal (mobile phone 1), wherein the received power level of the external RFID tag is measured in advance, and the position information is measured at the position. The current position acquired by the acquisition unit (GPS unit 33 in FIG. 1) with reference to the history information stored in association with the received power level (S33, S35) Based on the received power level corresponding to the distribution (S37, S43), and controls the detection operation for detecting a received signal of an external reader device (S39, S41, S45, S49).

  Specifically, first, the flow starts with an initial state (step S30) where the mobile phone 1 of the user A enters an area where the detection operation can be started (cell B of the mobile phone network 40 in FIG. 7). In step S31, it is determined whether or not the mobile phone 1 is within an area of the registered RFID tag reader / writer device 50 of the mobile phone network 40 (step S31). Specifically, the control unit 25 of the mobile phone 1 inquires of the mobile phone network 40 whether or not there is a registered RFID tag reader / writer device 50 in the current area via the mobile phone wireless unit 29.

  If it is determined that the area is within the area (Yes in S31), the process proceeds to step S33, and the following description will be made assuming that the mobile phone 1 has moved into the cell B of the mobile phone network 40 of FIG. In step S <b> 33, in the mobile phone 1, the GPS unit 33 acquires position information (latitude and longitude) of the current location from the GPS 42. In step S35, the history information 37 of the RFID tag 10 within the same latitude / longitude of the GPS 42 saved in the past or within a fixed distance range centered on the latitude / longitude is read from the storage unit 27 and acquired. The history information 37 may be stored in the storage unit 27 of the mobile phone 1 in advance, or may be acquired from a server of the mobile phone network 40 at any time, or acquired from a server periodically or as needed. You may preserve | save in the memory | storage part 27 if possible.

  In step S37, the reception power level of the reception power history information 37 of the RFID tag 10 at the same position in the comparison determination unit 21 (FIG. 1) of the mobile phone 1 is larger than a threshold that can be detected by the RFID tag 10. Compare and judge. If it is determined that it is greater than the threshold (Yes in S37), in step S39, the RFID control unit 19 (FIG. 1) sets the pause time between the magnetic field generation times of the RFID tag 10 from amsec to bmsec. change. Here, as an example in which specific numerical values are applied, as shown in FIGS. 4A and 4B, magnetic field generation is started with a = 3 msec and b = 30 msec. Here, as shown in FIG. 4 (a), the normal default value of the active tag according to Non-Patent Document 1 is a lower limit value of 3 msec, and is 30 msec in the case of maximum extension. An example in accordance with the standard is not limited. Further, the pause time can be configured to be proportional to the reception level in a stepwise manner within the range of the maximum value of b of 30 msec or less.

  Note that it is considered that a plurality of received power levels stored in the history information 37 exist for each position depending on the date, time, and the like. The received power level may change depending on the date and time. Therefore, when the received power level stored in the history information 37 is used for determination, the received power level corresponding to the current date and time may be extracted and used in consideration of the date and time information. When a plurality of histories are stored, the average value may be calculated and used for determination. When taking the average value, processing such as excluding minimum and maximum values at which the power level is considered unstable may be performed. Alternatively, when a plurality of histories are stored, the minimum value may be adopted. By adopting the minimum value, it is possible to reduce the probability of occurrence of reception power detection errors.

  On the other hand, when the received power level of the received power history information 37 of the RFID tag 10 at the same position is equal to or lower than the threshold value in step S37 (No in S37), the process proceeds to step S41, and the RFID control unit 19 (FIG. 1) The magnetic field generation time period when 10 is in the reader / writer mode is changed so as to increase from cmsec to dmsec, and magnetic field generation is started. As an example in which specific numerical values are applied, it is possible to change from c = 50 msec to d = 100 msec as shown in FIGS. 4 (a) and 4 (c). Also in this case, the value after the change of d may be changed stepwise so as to be inversely proportional to the reception level of the RFID tag 10.

  In step S43 following step S39 and step S41, the comparison determination unit 21 (FIG. 1) determines whether or not the received power level received by the RFID tag 10 is higher than a threshold value. If it is determined that the value is higher than the threshold (Yes in S43: History E to G in FIG. 7), the process proceeds to Step S45, and the RFID tag reader / writer enters the “Ready” state in which the RFID tag 10 can communicate (S1: FIG. 3). Transition is made by responding to a command from the device 50. On the other hand, if it is determined in step S43 that the received power level is equal to or lower than the threshold (No in S43: history AD in FIG. 7), the process proceeds to step S47, and the detection operation retry count or retry time. The RFID controller 19 determines whether or not is equal to or greater than the upper limit value. If it is less or shorter than the upper limit (No in S47), the detection operation is repeated. If the number of retries of the detection operation or the retry time is greater than or equal to the upper limit value in step S47 (Yes in S47), the process proceeds to step S49 and the detection operation is stopped.

  If it is determined in step S31 that the reader device is outside the registered area (No in S31), the process proceeds to step S49, where the control unit 25 or the RFID control unit 19 of the mobile phone 1 The tag 10 is shifted to the “Power-off” state (S0: FIG. 3), and the reception detection operation is stopped.

  As described above, according to the mobile terminal of the present embodiment, by controlling the detection operation of the external tag reader device according to the past received power level of the current position, power consumption can be reduced and connection can be reduced. A highly reliable portable terminal that reduces the probability of error is provided. Specifically, when the detection operation of the tag of the RFID tag 10 built in the mobile phone 1 or the reader / writer device is started, the history information 37 of the received power level in the past with the external tag at the current location is referred to, In a position where the received power level from the tag on the side is sufficiently high, the magnetic field generation time in the reader / writer mode on the mobile phone 1 side is shortened, that is, the reception detection time of the tag on the other side is shortened (the initial value becomes the minimum value). (If not, it is not changed.) By changing and changing the setting of the pause time of the magnetic field reception detection operation, the power saving effect of the cellular phone 1 can be obtained. Thereby, the battery of the mobile phone 1 can be made long lasting.

  Further, when the detection operation of the tag of the active RFID tag 10 incorporated in the mobile phone 1 and the reader / writer device is started, the history information 37 of the received power level in the past of the external tag at the current location is referred to, and the external At a position where the received power level from the tag is low, the magnetic field generation time in the reader / writer mode on the mobile phone 1 side is lengthened, that is, the reception detection time of the tag on the partner side is lengthened, and the pause time when the magnetic field is generated is shortened. (If the initial value is the minimum value, no change is made), it is possible to improve the success rate of establishing a communication connection in a place where the reception power level is low.

(Second embodiment)
FIG. 9 is a block diagram showing a main configuration of the mobile phone 1 according to the embodiment of the present invention. Since the mobile phone 1 of this embodiment refers to the history in the reception detection start area and, in the case of a place where the reception power level is low, the mobile phone 1 of this embodiment starts the operation of reception detection and the measurement value operates. Is different from the history information in that the user is guided to a position where the received power level is good.

  The cellular phone 1 according to the present embodiment refers to the history information 37 stored in the storage unit 27 and acquires the received power level of the history information 37 corresponding to the current position information acquired by the position acquisition unit (GPS unit 33). Determining unit 73 that determines whether the received power level acquired by the acquiring unit 71 that acquires the received power level is equal to or lower than a threshold, and the determined unit 73 determines that the received power level is equal to or lower than the threshold. The search unit 75 refers to the history information 37 to search for the position information of the nearest position where the received power level is equal to or higher than the threshold, and guides the user to the nearest position where the received power level searched by the search unit 75 is equal to or higher than the threshold. Presenting unit 77.

  Specifically, the mobile phone 1 of the present embodiment includes an acquisition unit 71, a determination unit 73, a search unit 75, and a presentation unit 77 in addition to the configuration of the mobile phone 1 of the above embodiment. The communication system according to the present embodiment includes a server 60 connected to the mobile phone 1 via the mobile phone network 40 and a database 62. The server 60 transmits the history information 37 stored in the history storage unit to the history storage unit (database 62) storing the history information 37 and the mobile terminal (mobile phone 1) via the network (mobile phone network 40). A transmission unit (not shown). The database 62 stores various types of information including history information 37 in which position information of a position where the received power level of the RFID tag is measured in advance is associated with the received power level measured at the position.

  The acquisition unit 71 refers to the history information 37 stored in the storage unit 27, and the past information of the history information 37 corresponding to the current position acquired by the GPS unit 33, the location of the same coordinates, or the position information of the peripheral coordinates. Get the received power level. The determination unit 73 determines whether or not the received power level acquired by the acquisition unit 71 is equal to or less than a predetermined threshold. When the determination unit 73 determines that the received power level is less than or equal to the threshold value, the search unit 75 refers to the history information 37 and searches for position information (latitude and longitude) of the nearest position where the received power level is greater than or equal to the threshold value.

  Here, for example, as shown in FIG. 10, if the mobile phone 1 of the user A exists in the peripheral area of the history B, the search unit 75 searches the history information 37 to obtain the history G having a good reception power level. get. Returning to FIG. 9, the presentation unit 77 guides the user to the nearest position (latitude and longitude) where the received power level searched by the search unit 75 is equal to or higher than the threshold. For example, the user can be guided by indicating the direction and distance to the nearest position where the received power level is equal to or greater than the threshold. The presentation unit 77 guides the user through a display unit (not shown) such as an LCD (Liquid Crystal Display) or an organic EL (ElectroLuminescence) display, or a user interface unit such as a speaker (not shown). For example, it is possible to guide the user by displaying a guidance screen to be described later on the display unit or outputting voice guidance or the like from a speaker.

  FIG. 11 is a diagram illustrating an example of a guidance screen of the mobile phone according to the present embodiment. The guidance screen 81 is displayed on the display unit of the mobile phone 1. As shown in FIG. 11, the guidance screen 81 has a current position mark 83 indicating the current position of the user at the center, a current position latitude / longitude display unit 84, and a position where the received power level searched by the search unit 75 is good. A position mark 85, a good position latitude / longitude display unit 86, a moving direction presentation arrow 87 indicating a direction from the current position to the good position, and a direction distance presenting unit 89 indicating a message indicating the direction and distance between the current position and the good position; ,including. In the current location latitude / longitude display section 84 and the good position latitude / longitude display section 86, for example, "N352235" indicates "35 degrees 22 minutes 35 seconds north" and "E139350". Indicates “Eastern longitude 139 degrees 33 minutes 50 seconds”. The direction distance presentation unit 89 presents a message for guiding the user from the current position to the good position. In FIG. 11, a message for guiding the user to go 15 meters southwest (SW) is presented.

  In this embodiment, it is assumed that the position of the RFID tag reader / writer device 50 on the opposite side is a fixed position. However, appropriate guidance may not be possible when the amount of recorded history information 37 is small. Therefore, it is desirable to have a means by which position information (latitude and longitude) can be acquired on the mobile phone 1 side. It is desirable that the opposite device side obtains position information (latitude and longitude) from the GPS 42, and that information can be obtained by the mobile phone 1 of the user A via the mobile phone network 40. ) Is a fixed known value, the history information 37 stored in advance in the storage unit 27 in the device on the mobile phone 1 side of the user A or in the database 62 of the server 60 of the mobile phone network 40 is stored in the mobile phone network. It is realizable by the structure of acquiring via 40.

  In addition, in order to realize a user interface that can be guided to a position where the tag reception level is good, it is possible to link the map information and the latitude / longitude information, but it is not always necessary to link the map information to the current position. It can also be shown by the relative direction and distance from.

  The operation of the mobile phone 1 of the present embodiment configured as described above will be described below. FIG. 12 is a flowchart showing an example of the operation at the time of guidance of the mobile phone 1 of the present embodiment. Hereinafter, description will be made with reference to FIG. 1 and FIGS. 9 to 12.

  First, it is assumed that the history A to G of the position and tag reception level shown in FIG. Then, an area where the user's mobile phone 1 can start detection, that is, a stage where the user enters the cell B is defined as an initial state (step S60). Here, steps S31 to S41 and S49 are the same as those in the flowchart of FIG.

  After step S39 or step S41, in step S73, the determination unit 73 (FIG. 9) determines whether or not the reception power level in reception detection is higher than a threshold value. If the received power level is higher than the threshold (YES in S73), the process proceeds to step S75, and the control unit 25 or the RFID control unit 19 (FIG. 1) enters the state of “Ready” in which the RFID tag 10 can communicate with the mobile phone wireless. Transition is made by responding to a command to the RFID tag reader / writer device 50 (FIG. 10) via the unit 29 (FIG. 9).

  On the other hand, if it is determined in step S73 that the RFID tag 10 is equal to or less than the operable threshold (NO in S73), the process proceeds to step S77, the search unit 75 refers to the history information 37, and The shortest good point of the position information (latitude and longitude) at which the received power level of the RFID tag 10 on the mobile phone 1 side that can communicate in the reader / writer mode on the mobile phone 1 side of the user is equal to or higher than the threshold is searched.

  As shown in FIG. 10, when the mobile phone 1 is at the point of the history B, if the history information 37 is searched and the position of the history G is searched as the shortest reception good position, in step S79, the mobile phone 1 The control unit 25 notifies the user of the mobile phone 1 of the result by the presenting unit 77, for example, displays the above-described guidance screen 81 of FIG. 11 on the display unit of the mobile phone 1, and receives the user. It can be guided to a good position.

  Then, the process proceeds to step S81, and the mobile phone 1 starts a reception detection operation (magnetic field generation operation). Thereafter, the process returns to step S73, and the normal operation of the RFID tag 10 is performed. The operation for starting the subsequent reception detection is the same as the operation of the above embodiment, and the description thereof is omitted.

  As described above, according to the communication system of the present embodiment, when the use of the RFID tag 10 of the mobile phone 1 is started at a position where the reception power level is low, the user is guided to a position where the reception power level is high. Therefore, the user convenience is improved.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

  For example, in the mobile phone 1 of the above embodiment, the transmission unit (mobile phone radio unit 29, mobile phone antenna) that transmits the history information 37 stored in the storage unit 27 to the server 60 via the network (mobile phone network 40). 31) may be further provided. In the mobile phone 1 of the above-described embodiment, an acquisition unit (mobile phone) that communicates with the server 60 (database 62) that holds the history information 37 via the network (mobile phone network 40) and acquires the history information 37 from the server 60. A telephone radio unit 29) may be further provided. The history information 37 acquired by the acquisition unit can also be stored in the storage unit 27.

  In the communication system of the present invention, the server 60 includes a receiving unit (not shown) that receives the history information 37 from the mobile terminal (mobile phone 1) via the network (mobile phone network 40). The recorded history information 37 can be stored in the database 62.

It is a block diagram which shows the structure of the mobile telephone which concerns on embodiment of this invention. It is a figure which shows an example of the structure of the log | history information memorize | stored in the memory | storage part of the mobile telephone of FIG. It is a figure which shows the state transition of the mobile telephone of this embodiment. It is the figure which showed the magnetic field generation time and rest time of the magnetic field generation period of the mobile telephone of this embodiment. It is a flowchart which shows an example of operation | movement of the mobile telephone of this embodiment. It is a figure which shows an example of the positional relationship with the mobile telephone network of the mobile telephone of this embodiment. It is a figure which shows another example of the positional relationship with the mobile telephone network of the mobile telephone of this embodiment. It is a flowchart which shows another example of operation | movement of the mobile telephone of this embodiment. It is a block diagram which shows the principal part structure of the mobile telephone of embodiment of this invention. It is a figure which shows an example of the guidance of the mobile telephone of this embodiment. It is a figure which shows an example of the guidance screen of the mobile telephone of this embodiment. It is a flowchart which shows another example of operation | movement of the mobile telephone of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cellular phone 10 RFID tag 11 RFID antenna 13 Regulator 15 Received power detector 17 Modulator / Demodulator 19 RFID control unit 21 Comparison judgment unit 23 RFID storage unit 25 Control unit 27 Storage unit 29 Mobile phone radio unit 31 Cell phone antenna 33 GPS unit 35 GPS antenna 37 History information 40 Mobile phone network 44 RFID tag communicable area 50 RFID tag reader / writer device 60 Server 62 Database 71 Acquisition unit 73 Determination unit 75 Search unit 77 Presentation unit 81 Guide screen 83 Current location mark 84 Current location latitude Longitude display section 85 Good position mark 86 Good position latitude / longitude display section 87 Moving direction presentation arrow 89 Direction distance presentation section

Claims (13)

Acquisition means for acquiring current position information;
A communication means for selectively switching between a reader / writer mode for performing wireless communication with an external RFID tag and a tag mode for performing wireless communication with an external tag reader device;
Detecting means for detecting a received power level of a received signal when the communication means communicates with the external RFID tag in the reader / writer mode;
The current information obtained by the obtaining unit is obtained by referring to history information in which the position information of the position where the received power level of the external RFID tag is measured in advance and the received power level measured at the position are stored in association with each other. And a control means for controlling a detection operation of the external tag reader device based on the received power level corresponding to the position information. The mobile terminal according to claim 1,
With reference to the history information, based on the received power level in the history information corresponding to the current position information, whether or not the received power level at the current position detected by the detection means is equal to or less than a first threshold value. A first threshold value judging means for judging,
The control means includes
When the first threshold value determining means determines that the received power level at the current position is less than or equal to the first threshold value, the detection time for performing the detection operation of the external tag reader device is set to a predetermined detection time. And setting a pause time between the detection times to pause the detection operation to a predetermined pause time,
When the first threshold determining means determines that the received power level at the current position is not less than or equal to the first threshold, the pause time is set longer.
A portable terminal that controls the communication means according to the set detection time and pause time. The mobile terminal according to claim 2,
The control means includes
A portable terminal that sets the detection time to a minimum value when the first threshold determination means determines that the received power level at the current position is not less than or equal to the first threshold. The mobile terminal according to any one of claims 1 to 3,
With reference to the history information, based on the received power level in the history information corresponding to the current position information, whether or not the received power level at the current position detected by the detecting means is equal to or greater than a second threshold value. A second threshold value judging means for judging,
The control means includes
When the second threshold determination means determines that the received power level at the current position is greater than or equal to the second threshold, the second threshold determination means sets a predetermined detection time for performing the detection operation of the external tag reader device, and Set a predetermined pause time between the detection times to pause the detection operation,
When the second threshold value determining means determines that the received power level at the current position is not equal to or higher than the second threshold value, the detection time is set longer.
A portable terminal that controls the communication means according to the set detection time and pause time. The mobile terminal according to claim 4,
The control means includes
A portable terminal that sets the pause time shorter than the predetermined pause time when the second threshold value judging means judges that the received power level at the current position is not equal to or higher than the second threshold value. The mobile terminal according to any one of claims 1 to 5,
Means for referring to the history information and obtaining the received power level of the history information corresponding to the current position information obtained by the obtaining means;
Means for determining whether the received power level acquired by the means for acquiring the received power level is a threshold value or less;
Means for referencing the history information when the received power level is determined to be less than or equal to the threshold by the determining means, and searching for position information of a nearest position where the received power level is greater than or equal to the threshold;
Means for guiding the user to the nearest position where the received power level searched by the searching means is equal to or higher than a threshold value. The mobile terminal according to any one of claims 1 to 6,
A storage unit that associates the position information acquired by the acquisition unit with the received power level detected by the detection unit at a current position and stores the position information as the history information;
The portable terminal that controls the detection operation of the external tag reader device with reference to the history information stored in the storage unit. The mobile terminal according to claim 7, wherein
The portable terminal further provided with the transmission means which transmits the said log | history information memorize | stored in the said memory | storage means to a server via a network. The mobile terminal according to any one of claims 1 to 8,
A portable terminal further comprising means for communicating with a server holding the history information via a network and acquiring the history information from the server. The mobile terminal according to claim 9, wherein
A portable terminal further comprising storage means for storing the history information acquired by the means for acquiring the history information. A mobile terminal according to any one of claims 1 to 10,
A communication system comprising a server connected to the mobile terminal via a network,
The server
History storage means for storing the history information;
A communication system comprising: transmission means for transmitting the history information stored in the history storage means to the portable terminal via the network. The communication system according to claim 11, wherein
The server
Receiving means for receiving the history information from the portable terminal via the network;
Means for storing the history information received by the receiving means in the history storage means. An acquisition unit for acquiring current position information;
A communication unit for selectively switching between a reader / writer mode for performing wireless communication with an external RFID tag and a tag mode for performing wireless communication with an external tag reader device;
A detection unit that detects a reception power level of a received signal when the communication unit communicates with the external RFID tag in the reader / writer mode, and a method for controlling a detection operation of the external tag reader device in a portable terminal. And
The current information acquired by the acquisition unit with reference to the position information of the position where the received power level of the external RFID tag is measured in advance and the history information stored in association with the received power level measured at the position. A mobile terminal control method for controlling a detection operation of the external tag reader device based on the received power level corresponding to position information.

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