JP2006052945A - Communication system and communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cause times in devices of the same rank to match with each other in cases where communication methods different in transmission time get mixed in a communication system for transmitting time infomation. <P>SOLUTION: Slave devices 3, each comprising a wireless IC tag, decode time information received from higher-rank devices to correct time measurement time of a time measurement part based on the time information. They produce and transmit transmission information for correcting time measurement time of lower-rank devices with rank information showing own ranks added to the measurement time of the measurement part. The time information is transmitted/received through one or both of wireless and wired transmission routes. The slave devices 3 acquire time information from devices of ranks as high as possible. Time measurement time of slave devices 3 of the same rank in the communication system 1 is kept constant independently of the kind of transmission route for receiving time information by delaying the outputting of the information by a delay circuit by a previously set and definite period of time, when receiving time information via a wired transmission route capable of higher speed transmission than a wireless transmission route. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a communication system with improved reliability of time information transmission in a communication system that transmits time information from a higher-level device to a lower-level device and corrects the time of the lower-level device, and a device constituting the communication system. About.

  The parent clock transmits the reference time information wirelessly, such as radio waves, and the child clocks placed around it receive this and correct the time based on the reference time information of the parent clock to match the time of the parent clock A wireless parent-child clock system is known. The reference time of the parent clock is generated by receiving radio waves from an external standard time information source. Since this wireless parent-child clock system does not require a wire for relay transmission of time information, a plurality of child clocks that display times that coincide with the time of the parent clock are arranged relatively freely on the premises or on the premises. It is suitable for.

For example, in a wireless parent-child clock system installed in a relatively large site or a complex building, the parent clock can relay the reference time information to the child clock, and the position of the child clock can be relatively reduced. There exists what is disclosed by patent document 1 as what can be selected or changed freely.
JP 2002-148371 A

  In the parent-child clock system described in Patent Document 1, since time information is transferred in a relay manner in the system, a wireless parent-child clock system can be installed in a relatively large site or a complex building. The position can be selected or changed relatively freely. However, in the conventional parent-child watch system, time information is transmitted using weak radio waves that are not subject to legal regulations and do not require a license, so the transmission distance is limited, and radio wave reception environments such as noise In some cases, sufficient time information cannot be transmitted.

  In addition, it may be difficult to unify all the communication methods of the devices that construct the parent-child clock system into the same method. Depending on the circumstances, a different communication method may be adopted, such as incorporating communication using a communication cable in part. There is a case to be forced. However, with such a system configuration, since the transmission delay differs depending on the communication method, there is a possibility that even the slave clocks positioned at the same rank will be out of time with each other.

  The same problem is not limited to clocks that display timekeeping time as a main function, but has a timekeeping function that receives time information from other devices and corrects its own timekeeping time while transmitting its own timekeeping time. Various electronic devices (for example, information processing terminals (PDA (Personal Data Assistance), notebook computers, laptop computers, handy terminals), wireless tags, IC tags, wireless IC tags, IC chips, game machines, acoustic devices, etc. ) In common.

Accordingly, an object of the present invention is to solve the problems of the prior art described above.
Further, the present invention is to make the timekeeping times of the devices of the same rank coincide with each other even when a plurality of communication methods are mixed in the transmission of time information.

In order to achieve this object, the communication system according to the first aspect of the present invention includes a parent device that transmits time information, the time information transmitted from the parent device, and the own communication device based on the received time information. A communication system including a slave device that corrects the time measured by the time measuring means,
The child device is
Data processing means for executing predetermined data processing based on the time measured by the time measuring means;
First receiving means for receiving time information by the first communication method;
Second receiving means for receiving time information in a second communication method having a communication time longer than that of the first communication method;
Delay means for delaying the time information received by the first receiving means by a predetermined time;
Selecting means for selecting one of the time information received by the first receiving means and the time information received by the second receiving means;
When the time information received by the second receiving means is selected by the selecting means, the timekeeping time is corrected based on the time information, and the time information received by the first receiving means is selected by the selecting means Sometimes the correcting means for correcting the time measured by the time measuring means based on the time information delayed by the delay means;
Means for transmitting time information for correcting the time of another child device based on the corrected timekeeping time;
It is characterized by having.

  With the above configuration, the present invention can select an appropriate communication method as necessary. In addition, it is possible to prevent a situation in which the timekeeping times of the slave devices having the same relative position (rank) vary due to a difference in communication methods.

  For example, the second communication method is a wireless communication method, and the first communication method is a wired communication method.

  The delay means gives a delay time corresponding to a time difference between a communication time of time information according to the second communication method and a communication time of time information according to the first communication method. As a result, devices located in the same rank can receive time information at substantially the same timing regardless of the communication method.

  The selection means uses, for example, both time information received by the first receiving means according to the first communication method and reception of time information received by the second receiving means according to the second communication method, The time information of the better is adopted.

  For example, the delay means delays the time information by a time such that the time measured by the time measuring means of a plurality of child devices located in the same order substantially matches the transmission order of the time information from the parent device.

The slave device is composed of, for example, a wireless tag or an information terminal.
Alternatively, the slave device is constituted by, for example, a wireless tag including data storage means and a package. In this case, the data processing means stores time information indicating the time measured by the time measuring means in the data storage means in response to a predetermined trigger signal, and the time information stored in the data storage means is directly or data stored. Means for processing and outputting to the outside wirelessly, the package is made of a material capable of transmitting wireless signals and encloses the whole.

  The communication device of the present invention includes a receiving unit that receives time information transmitted from another device, a delay unit that outputs the time information received by the receiving unit with a predetermined time delay, and a delay unit that delays the time information. Correcting means for correcting the time held by itself based on the corrected time information, transmitting means for transmitting time information for correcting the time of another child device based on the corrected own time, and the self Data processing means for executing predetermined data processing based on the time of

According to the communication system of the present invention, the communication method of time information can be selected, and the expandability and flexibility of the network are increased.
Also, the delay means can equalize the difference in transmission delay due to the difference in communication method.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows an outline of a communication system 1 according to a first embodiment of the present invention. As illustrated, the communication system 1 includes a parent device 2 and a plurality of child devices 3 (rank 1 child devices 3A1 and 3A2, a plurality of rank 2 child devices 3B1 and 3B2, and a plurality of rank 3 child devices 3C1. 3C2 and 3C3, rank 4 child device 3D1, rank 5 child device 3E1), and a plurality of repeaters 4 (41 and 42).

  Between parent device 2 and rank 1 child devices 3A1 and 3A2, between rank 1 child device 3A1 and rank 2 child device 3B1, between rank 2 child device 3B2 and repeater 41, repeater 41 and rank 4 Between child devices 3D1 of rank 2, child device 3B1 of rank 2 and child device 3C1 of rank 3, child device 3B2 of rank 2, child devices 3C2 and 3C3 of rank 3, child device 3C3 of rank 3 and repeater 42, the repeater 42 and the rank 5 child device 3E1 are connected so as to be capable of bidirectional communication with radio waves having a predetermined output (power) and a predetermined frequency. The output and frequency are chosen to be values that do not require a license or permission under legal regulations. The radio waves may have the same frequency.

  In addition, the parent device 2 and the rank 1 child device 3A1 and the rank 1 child device 3A2 and the rank 2 child device 3B2 are connected to each other by wired communication 51 or 52 so as to be capable of bidirectional communication. Wired communications 51 and 52 are for wired serial communications such as RS232C, RS422 / 485, USB, IEEE1394 (fire wire), wired parallel communications such as Centronics, GP-IB, and PC (personal computer) such as Ethernet (registered trademark). Or other general-purpose wired communication or optical communication using an optical fiber. Furthermore, optical communication using near infrared rays or wireless communication using ultrasonic waves may be used. The parent device 2, the rank 1 child device 3A1, the rank 1 child device 3A2, and the rank 2 child device 3B2 each include a transmission / reception unit 51A or 52A (connector) for the wired communication 51 or 52. The parent device 2 and the rank 1 child device 3A1 are duplexed so that information including time information can be transmitted and received by both low-power wireless and wired communication 51.

  The parent device 2 has the configuration shown in FIG. That is, the parent device 2 receives an external standard time information radio wave (broadcast time signal, long wave standard radio wave, global positioning system (GPS) time information, etc.) by the antenna 20 and the receiver 21, and the decoder 22 Use the time code of the standard time information. Not limited to this, the parent device 2 may receive the standard time information via a telephone such as a telephone JJY or a cable line. The time for the parent device 2 to receive the standard time information from the outside can be controlled in a predetermined time zone by the identification number storage unit 27 that controls the power supply control unit 29 that supplies power to the receiver 21. The received time code of the standard time information is sent to the time correction unit 23 via the decoder 22. Based on the time code of the standard time information, the time correction unit 23 creates correction information to be corrected so as to coincide with the standard time, and sends the correction information to the time measuring unit 24. The timer unit 24 corrects the time display of the time display unit 25 by correcting its own time so as to match the standard time. The timer unit 24 sends reference time information to the encoder 26 to be transmitted to the child device and to correct the time of the child device. The encoder 26 receives data for identifying that it is information from the parent device 2 from the identification number storage unit 27, attaches it to the reference time information, and sends it to the transmitter 28.

  The transmitter 28 is supplied with power from the power supply control unit 29 by the identification number storage unit 27 at a predetermined time when the parent device 2 transmits the reference time information. Then, via the transmitter 28 and the antenna 20, information for identifying information from the parent device is added to the reference time information, and the information is transmitted toward the child device 3 with a carrier wave having a predetermined frequency and output.

  Furthermore, the time measuring unit 24 also sends reference time information for correcting the time of the slave device to the slave device 3 to the serial signal encoder 61. The serial signal encoder 61 encodes time information in a form suitable for wired communication, for example, a format such as RS422, and receives data from the identification number storage unit 27 for identifying the information from the parent device 2. The reference time information is sent to the transmitter / receiver 62 for wired communication. The transmitter / receiver 62 is supplied with power from the second power control unit 63 by the identification number storage unit 27 when a predetermined time for the parent device 2 to transmit the reference time information is reached. Then, the transmitter / receiver 62 attaches information for identifying information from the parent device to the reference time information via the transmission / reception unit 51A (connector) connected to the wired communication 51, and uses the wired communication 51 in the communication system 1. It transmits toward child apparatus 3A1.

  As will be described later, the parent device 2 receives information conveying the state from each child device in the communication system 1 by the antenna 20 and the receiver 21, and the decoder 22 identifies the information from each child device and displays the display unit 19 To display the status of each child device. Further, information indicating the state from each child device in the communication system 1 is received by the transmission / reception unit 51A and the transmitter / receiver 62, the information is identified from each child device by the second decoder 64, and each child device is displayed by the display unit 19. Displays the status of. If the status data from each child device in the communication system 1 is abnormal, for example, if the time information cannot be decoded or received, the administrator of the communication system 1 can know this by viewing the display unit 19. it can.

  The radio waves transmitted by the parent device 2 and the radio waves described later transmitted by each child device may have the same frequency. However, as will be described later, transmission is performed by shifting the time so that the transmission times of the parent device 2 and the child device do not match, thereby avoiding interference. Instead of this, interference may be avoided by setting the radio wave transmitted by the parent device 2 and the radio wave transmitted by each child device to different frequencies.

  The power supply control unit 29 follows the current time supplied from the time measuring unit 24 and the identification number supplied from the identification number storage unit 27 identifying the parent device 2, and the transmission time of the reference time information and the child device 3. Only during radio wave reception time, power is sent to the transmitter 28, the receiver 21, and other necessary circuits to save power consumption.

  The slave devices 3A1, 3A2, 3B1, 3B2, 3C1, 3C2, 3C3 shown in FIG. 1 are constituted by so-called wireless IC tags, for example, and as shown in FIG. 3, a communication circuit 301, a timer circuit 302, and a memory 303 and a processor 304, which are enclosed in a package 305.

The communication circuit 301 includes a wireless communication circuit for wireless communication including an antenna, a high-frequency circuit, and the like, and a wired communication circuit including a connector (jack) for communication cable connection, and performs communication with other devices.
The timer circuit 302 counts the current time.
The memory 303 stores an operation program of the processor 304 and identification information of the child device 3. Also, it functions as a work area for the processor 304.

  The processor 304 is time correction information (information for correcting the time measured by the timer circuit 302 from the parent device 2 or the child device 3 higher than itself) via the communication circuit 301. Is referred to as reference time information, and information from the slave device 3 is referred to as reference time information), and based on the time information included in the received time correction information, the time measured by the timer circuit 302 is corrected and corrected. Based on the time information, the time correction information for correcting the time measured by the wireless IC tag of lower rank than the self is transmitted via the communication circuit 301. Further, at the next uplink, a reception status signal indicating the reception status of the time correction information (success / failure of reception, quality of received data, propriety of time correction, transmission status downstream), etc. is transmitted via the communication circuit 301. To send.

  The processor 304 performs various data processing according to the function of the wireless IC tag. For example, the processor 304 stores identification information (ID; individual identification number storage unit 37 described later for communication control) in transmission information, for example, in uplink for transmitting information from a lower rank apparatus to an upper rank apparatus. May be the same as or different from the individual identification number provided). As a result, the identification information is transmitted to the parent device 2 in a relay manner, and the parent device 2 can confirm the presence / absence of the child device 3, for example, can confirm the presence of an article attached with a wireless IC tag. The processor 304 collects output data of various sensors (temperature sensor, humidity sensor, pressure sensor, gas meter, water meter, power meter) arranged inside or outside the wireless IC tag, and The data is stored in association with the clock time, and the collected data is processed as necessary, and wirelessly transmitted through the communication circuit 301 together with the identification information at the time of uplink. For example, if the wireless IC tag is a data logger such as a thermometer, the processor 304 is connected to an internal or external temperature center, and uploads a data history such as a temperature history obtained at a predetermined time interval together with identification information. Included in the transmission information when linking. These pieces of information are also transmitted to the parent device 2, and the parent device 2 can check the temperature history of each device. When the processor 304 receives an inquiry command addressed to itself from the outside via the communication circuit 301, the processor 304 transmits a response signal including its own identification information (ID) via the communication circuit 301. Further, the time when the inquiry command is received, the identification information of the issuer of the inquiry command, etc. are recorded in the memory 303. When a predetermined read command is received, the history information stored in the memory 303 is transmitted via the communication circuit 301. You may make it transmit to an external device.

  The package 305 is formed of a radio wave-transmitting resin material in a rectangular parallelepiped or cubic shape having, for example, several centimeters to several millimeters, and encloses the entire package 305 while enabling communication with the outside through the communication circuit 301. The package 305 is provided with a jack (transmission / reception unit) J for connecting a wired cable.

Next, with reference to FIG. 4, the details of the configuration of the main functions of each of the child devices 3 (3A1 to 3E1) will be described by taking the child device 3A that directly receives the reference time information from the parent device 2 as an example.
Each child device 3 has substantially the same configuration as each other, and can communicate bidirectionally with the parent device 2 and other child devices 3 by wireless communication and / or wired communication.

  As shown in FIG. 1, the rank 1 child devices 3 </ b> A <b> 1 and 3 </ b> A <b> 2 are child devices capable of bidirectional communication with the parent device 2 directly by radio waves or wired communication 51. Although the rank 2 child devices 3B1 and 3B2 cannot directly communicate with the parent device 2 in both directions, the rank 2 child devices 3B1 and 3B2 are capable of bidirectional communication with the rank 1 child device 3A1 or 3A2 by radio wave or wired communication 52. is there. The rank 3 child devices 3C1, 3C2, 3C3 cannot directly communicate with the parent device 2 and the first child device 3A, but communicate with the rank 2 child device 3B1 or 3B2 by radio waves. It is a possible child device. The rank 4 child device 3D1 can bidirectionally communicate with the rank 2 child device 3B2 via the repeater 41. The rank 5 child device 3E1 can bidirectionally communicate with the rank 3 child device 3C3 via the repeater 42.

  Referring to FIG. 4 again, rank 1 child device 3A1 as an example of child device 3 receives wireless information including reference time information from parent device 2 by antenna 30 and receiver 31, and decoder 32 After receiving the time information, it is sent to the time correction unit 33. Further, the decoder 32 decodes the information indicating that it has been sent from the parent device 2 and sends it to the rank control unit 35. The rank control unit 35 stops the power supply to the receiver 31 and other circuits via the power supply control unit 39, and stops the reception for a predetermined time until the reception of the next reference time information.

  At the same time, the slave device 3A1 receives a serial signal such as RS422 including the reference time information from the master device 2 through the wired communication 51, the transmission / reception unit 51A (connector), and the transmitter / receiver 72. After decoding, the data is sent to the delay time adjustment unit 75.

  The delay time adjustment unit 75 delays the reference time information decoded by the second decoder 74 by a predetermined time Δt and supplies the delayed time to the time correction unit 33. This fixed time ΔT is based on the assumption that the communication time of time information by the wired communication 51, 52 is earlier than the communication time of time information by the wireless communication, and the communication time of the time information by the wireless communication between the devices and the wired communication. The difference between the time information and the communication time (for example, a time difference comprehensively including the time of demodulation, error check, error correction, etc.) is obtained by calculation or experiment based on device specifications and set. As a result, the timing for supplying the time information acquired by the wired communications 51 and 52 to the time correction unit 33 is delayed by a preset time Δt, and the output timing of the time information by the wired communications 51 and 52 and the time by the wireless communications are set. The difference between the output timings of information is eliminated, and the time correction timings of the child devices 3 of the same rank are made equal to each other, and sent to the time correction unit 33. The delay time adjustment unit 75 may be a FIF0 (First-in First-out) register or a shift register that outputs with a preset delay time, even using a delay line or the like.

  The second decoder 74 sends rank information indicating the time information transmitted from the parent device 2 to the rank control unit 35 as time information based on the wired communications 51 and 52. The rank control unit 35 stops the power supply from the second power supply control unit 73 to the transmitter / receiver 72 and other circuits, and stops reception for a predetermined time.

  The rank control unit 35 gives priority to time information having higher ranks when time information is successfully received in both wireless communication and wired communication. In the case of the child devices 3A1 and 3B1, since both are received from the parent device 2, there is no difference in rank. For this reason, priority is given to those who have succeeded in receiving the time information. However, if both have succeeded in receiving the time information, the time correction unit 33 corrects the time using the time information by wired communication as the default. Do.

  The rank control unit 35 includes time information sent from the parent device 2 (or another child device 3) in both the decoder 32 and the second decoder 74 (in this embodiment, time information by both wireless and wired). If the time code cannot be restored, the time correction by the time correction unit 33 is stopped. Then, for example, the power supply control unit 39 and the second power supply control unit 73 are instructed not to send the time information from the child device 3 to the other child devices 3 (for example, these power supply control units are time information transmission timings). The power is not supplied to the transceivers 38, 72, etc.). The rank control unit 35 (processor 304) stores such information in the memory 303 and the like, and at the time of uplink, wirelessly via the encoder 36, the transmitter 38, the antenna 30, or the serial signal encoder 71, The parent device 2 or the upper child device 3 is notified of the reception failure of the time information by wire via the transmitter / receiver 72 and the transmitter / receiver 51A or 52A. The notification of the child device 3 sent to the parent device 2 is displayed on the display unit 19 of the parent device 2 and / or the administrator of the communication system 1 or the management device via the transmitter 28 or the like of the parent device 2 Sent to.

The time correction unit 33 generates correction information for correcting its own time based on the reference time information received from the parent device 2 (wirelessly or by wire), corrects the time measured by the time measuring unit 34, and sets the time of the parent device 2. To match. In this example, a wireless IC tag is assumed as the slave device 3, and a display unit for displaying the time measured by the time measuring unit 34 is not arranged, but a display unit for displaying time information may be arranged. Good.
The timekeeping unit 34 creates rank-1 reference time information for correcting the time of the rank-2 child device 3B1 based on the timekeeping time, and sends it to the encoder 36 or the serial signal encoder 71. This rank 1 reference time information is transmitted at a predetermined transmission time of a rank 1 child device 3A1, which will be described later. The rank 1 reference time information is the time information of the time measuring unit 34 corresponding to the predetermined transmission time of the rank 1 child device 3A1, and is different from the reference time information from the parent device 2 in terms of time. Later time information.

  The encoder 36 or the serial signal encoder 71 adds data for distinguishing from the reference time information of the parent apparatus 2 to the rank 1 reference time information. That is, the rank control unit 35 sends data indicating that the time information to be transmitted is the reference time information of rank 1 to the encoder 36 and the serial signal encoder 71 based on the information from the decoder 32 or the second decoder 74. In addition, the individual identification number storage unit 37 gives the encoder 36 and the serial signal encoder 71 an individual identification number that is individual identification information for identifying the child device 3A1 from the other child devices 3 in the communication system 1. The encoder 36 and the serial signal encoder 71 include data indicating rank 1 reference time information from the rank control unit 35 in rank 1 reference time information from the time measuring unit 34, and an individual identification number storage unit 37. An individual identification number indicating a specific child device 3A1 is added and sent to the transmitter 38 and the transmitter / receiver 72.

  The transmitter 38 and the transmitter / receiver 72 transmit information to another child device 3 via the antenna 30 or the transmitter / receiver 51A or 52A (connector) at a predetermined transmission time. As will be described later, this predetermined transmission time is determined in advance by the rank and the individual identification number, and does not overlap with the transmission time of the parent device 2 and other child devices that use the same transmission frequency. It is avoiding. The transmission time of each child device is the rank of the child device, that is, the rank 1 child device 3A that directly receives the reference time information from the parent device 2, and the rank 1 reference time information from the rank 1 child device. In accordance with the rank 2 child device 3B and the rank 3 child device 3C receiving the rank 2 reference time information from the rank 2 child device, the time is sequentially shifted so as to be delayed. Furthermore, since there may be a plurality of child devices (for example, child devices 3A1 and 3A2 in rank 1, child devices 3B1 and 3B2 in rank 2, and child devices 3C1, 3C2, and 3C3 in rank 3) even at the same rank, Each child device is further subdivided according to the individual identification number of the child device and transmits it at the assigned transmission time.

  The power supply control unit 39 and the second power supply control unit 73 obtain their own rank from the rank control unit 35, obtain their own individual identification number from the individual identification number storage unit 37, and determine their own rank and individual identification. The timer 34 knows that the predetermined time assigned based on the number has been reached, and supplies power to the transmitter 38 or the transmitter / receiver 72 to perform transmission.

  The power supply control unit 39 and the second power supply control unit 73 are respectively connected to the receiver 31 and the transmitter / receiver 72 at a predetermined transmission time of the time information from the parent device 2 and the child device of higher rank than its own rank. Power supply is started, time information is received, and power supply to the receiver 31 and the transmitter / receiver 72 is stopped after reception. In this example, since the first slave device 3A1 has the highest rank, the receiver 31 and the transmitter / receiver 72 are operated during the transmission time of the parent device 2. As a result, power consumption for reception can be saved. In addition, the reception of the first or rank 2 reference time information transmitted by another child device is prevented, thereby preventing repeated correction of time and transmission of reference time information again.

  Further, as described above, the child device 3 transmits information such as whether or not the time information has been successfully received to the parent device 2 at a predetermined uplink time. As will be described later, this predetermined uplink time is a time zone different from the time information transmission time, and a different time is allocated for each rank and for each individual identification number. When the power supply control unit 38 and the second power supply control unit 73 know from the time measuring unit 34, the individual identification number storage unit 37, and the rank control unit 35 that the predetermined time has been reached, their own individual identification is performed. Power is supplied to the transmitter 38 and the transmitter / receiver 72 in order to uplink transmit the information including the number information and the success / failure of the reception of the time information to the parent device 2.

  Further, the child device 3A is a child device of a lower rank, for example, the child device 3B of rank 2 and the child device 3C of rank 3 share information about whether or not it can receive its own individual identification number and time information. When uplink transmission is performed to the device 2, radio waves are relayed. For this reason, the child device 3A supplies power to the receiver 31 and the transmitter / receiver 72 in a time zone in which the child device of the lower rank transmits reception information to the parent device, and receives radio waves from the child device of the lower rank. .

  The rank 2 child device 3B has the same configuration as the first child device 3A and performs a similar operation. The rank 2 child device 3B analyzes the fact that the rank 1 reference time information from the rank 1 child device 3A is received by the decoder 32 and the second decoder 74 and notifies the rank control unit 35 of the analysis. The rank control unit 35 identifies that it is a child device of rank 2, sends data indicating that the time information transmitted by itself is the reference time information of rank 2 to the encoder 36 and the serial signal encoder 71, Further, in order to perform reception and transmission at the reception time and transmission time allocated to the child device of rank 2, to the receiver 31 and the transmitter 38 or the transmitter / receiver 72 via the power supply control unit 39 and the second power supply control unit 73. Indicate the power supply time. After receiving the reference time information of rank 1, the receiver 31 and the transmitter / receiver 72 stop the reception until the reception time of the reference time information of the next rank 1 and receive time information transmitted by the child devices of other ranks. Prevent receiving. Further, the rank 32 reference time information used by the decoder 32 and the second rank child device 3C for time correction is sent to the encoder 36 and the serial signal encoder 71. The encoder 36 and the serial signal encoder 71 add information indicating the specific individual identification number of the child device 3B from the individual identification number storage unit 37 and the reference time information of rank 2 to the time information, and the transmitter. 38 and the transmitter / receiver 72. The rank 2 reference time information transmitted by the rank 2 child device 3B is time information at the transmission time assigned by rank 2 and the individual identification number as described later.

  In the above description of the operation, the rank 2 child device 3B is described as being in a state where it cannot receive the reference time information transmitted from the parent device 2, but if the reference time information can be received from the parent device 2, The time information transmitted by itself can be used as the rank 1 reference time information. In this way, the slave device 3 is generally in a state where it can be received when the time information of the higher rank is transmitted, detects whether it can receive the time information of the higher rank, and the time information of the higher rank. Can be received, it is switched to reception of the rank (it may be fixed with the initial setting).

  The time correction unit 33 corrects the time of its own clock unit 34 based on the reference time information of rank 1. Then, reference time information of rank 2 for correcting the time of the next rank 3 child device 3C is created and sent to the encoder 36 and the serial signal encoder 71. The encoder 36 and the serial signal encoder 71 add data for distinguishing from the reference time information of the parent apparatus to the rank-1 reference time information. Based on information from the decoder 32 and the second decoder, the rank control unit 35 sends data indicating that the time information to be transmitted is rank 1 reference time information to the encoder 36 and the serial signal encoder 71. The individual identification number storage unit 37 gives the individual identification number to the encoder 36 and the serial signal encoder 71. The encoder 36 and the serial signal encoder 71 include the data indicating that the rank is 2 from the rank control unit 35 and the individual identification number from the individual identification number storage unit 37 in the rank 2 time information from the timing unit 34. In addition, reference time information (transmission target information) of the second rank is generated and sent to the transmitter 38 and the transmitter / receiver 72, respectively. The transmitter 38 and the transmitter / receiver 72 transmit the reference time information to the other child devices 3. The predetermined transmission time is determined in advance by the rank and the individual identification number as will be described later.

  The rank 3 child devices 3C1, 3C2, 3C3, the rank 4 child device 3D1, and the rank 5 child device 3E1 have the same configuration as the first and rank 2 child devices 3A and 3B, and have similar operations. Do.

  Here, since the rank 4 child device 3D1 is in a position where radio waves cannot be directly received from the rank 2 child device 3B2, a necessary number of wave relays are performed between the rank 2 child device 3B2 and the rank 4 child device 3D1. For example, in the case of FIG. 1, bidirectional radio wave communication is performed with one relay 41 interposed. The repeater 41 (and 42) has substantially the same configuration as the child devices 3A, 3B, and 3C of each rank, and includes an individual identification number as a child device. The repeaters 41 and 42 are the ranks of the third and fourth child devices, respectively. Further, the repeaters 41 and 42 display whether or not radio waves can be received, the rank of the received radio waves, that is, the distinction of time information, and the transmission source thereof by the same display unit as that of the slave device. And 42 can be used. In addition, it is good also as what consists of a reception / transmission part for a simple radio wave repeater as a repeater.

  FIG. 1 shows the rank 1 child device 3A1 to the rank 5 child device 3E1, but it is also possible to arrange more child devices and connect them so as to be capable of bidirectional communication by radio waves in a relay manner.

  Each child device 3 has its own individual identification number in the individual identification number storage unit 37, but otherwise has the same configuration. When the reference time information from the parent device 2 is received by the rank control unit 35, rank 1 When the child device 3A receives rank 1 reference time information from the rank 1 child device 3A, the second (1 + 1) rank child device 3B receives the rank 2 reference time information from the rank 2 child device 3B. Is automatically ranked to the child device 3C of the third (2 + 1) rank. As a result, the child devices can be exchanged.

  Next, with reference to FIG. 5, time allocation at the time of downlink in which time information for time correction is transmitted between the parent device 2 and the child device 3 will be described. The downlink is performed, for example, once a day using 1 hour at 2am. However, the time required for each child device to receive and transmit the time information is the allocated time, 1 second in this example. Moreover, once the time information for time correction is received, the slave device 3 can prevent unnecessary power consumption because the receiver 31 and the transmitter / receiver 72 are turned off as described above. Subsequent reception of time information is not performed after the reception by the receiver is stopped, so that repeated time correction and transmission can be prevented. Each child device gives priority to time information such as reference time information that can be received, reference time information of rank 1, reference time information of rank 2 and the like that is higher in rank, that is, closer to the parent device. It is configured to receive. The downlink is not limited to once a day. If the downlink is performed once every two to three hours, the accumulated error of the devices in the system can be further suppressed. In addition, some low-accuracy devices have an error of about 1 second per day due to the influence of quality and temperature changes in the installation environment. In such cases, it is assumed that the downlink is performed once a day. For example, since there is a risk of deviating from the method of completing the communication within one second of the system of this example, it is difficult to adopt it for the slave device. If the system performs a downlink once every two to three hours, the accumulated error of the devices in the system can be suppressed, and even a low-precision device can be adopted as a child device, and the system can be constructed at low cost. Is possible.

First, the parent device 2 corresponding to rank 0 transmits the reference time information to the child device 3 at a predetermined timing before 2:00 am (for example, 1:59:59 am to 2:00:00 am for 1 second). The slave device 3 that has received this reference time information is automatically set as a rank 1 slave device by the function of the rank control unit 35, and the subsequent reception operation stops.
Subsequently, as shown in FIG. 5, the time information of the rank 1 child device 3A in which 1 minute from 2:00 am to 2: 1 am is rank 1, that is, the transmission time zone of the reference time information of rank 1 It is. This one-minute time zone is further subdivided into 60 time zones at 1-second intervals, and assigned in correspondence with the individual identification number (specific number between 1 and 60) of the first child device 3A. Wireless or wired transmission is performed in one second during the specified time zone. One minute from 2:01 to 2: 2 is the transmission time zone of the time information of the rank 2 slave device 3B, that is, the rank 2 reference time information. This one-minute time zone is further subdivided into 60 time zones at 1-second intervals, and assigned to correspond to the individual identification number of the rank 2 child device 3B (specific number between 1 and 60). Transmission is performed in 1 second of the specified time zone. The same applies when there are child devices of the following ranks. In this way, even if radio waves having the same frequency are used, there is no interference.

  Next, referring to FIG. 6, uplink (information on reception status) indicating the reception status of each child device from rank 1 to rank 3 child devices 3A, 3B, 3C to the parent device 2 is transmitted by radio waves. The time allocation of will be described. As illustrated in FIGS. 7A to 7C, the reception status information of each child device 3 includes rank, individual identification number, success / failure of reception of time information for time correction, and transmission of received time information. This includes information such as the original individual identification number and the success or failure of the correction of the timekeeping time. Also, depending on the function of the wireless IC tag that is the child device 3, as shown in FIGS. 7B and 7C, the identification information (ID; individual identification information of the wireless IC tag 3 is separate from the identification information. ) And information generated or collected by each child device 3 (for example, temperature / pressure / humidity history information, meter (gas meter, water meter, electric meter value, etc.) or information obtained by processing / processing this information The uplink is performed, for example, once a day using 1 hour at about 3 am, provided that the time required for each child device to transmit information is allocated within it. Therefore, wasteful power consumption can be prevented, and at the same time as the uplink starts, a reception operation for relaying is started in each child device 3. Collect it in the parent device and earn the entire system The situation is monitored and used for maintenance work, and if necessary, the position of the repeater can be changed or the position of the child device can be changed as shown in FIGS. In addition, the reception status information transmitted from the lower rank child device 3 is added to its own reception status information and transmitted to the higher level device.

  As shown in FIG. 6, uplink transmission is started from a lower rank child apparatus in reverse to the downlink case. That is, one minute from 3 o'clock to 3 o'clock is a transmission time zone of information of a rank 60 child device. This 1 minute time zone is further subdivided into 60 time zones at 1 second intervals, and 1 second of the time zone assigned for each individual identification number of the child device (specific number between 1 and 60). Wireless or wired transmission. The radio wave transmitted by the slave device is relayed to the master device 2 by being sequentially or wirelessly relayed by the host slave device.

  One minute from 3:55 to 3:56 is, for example, the transmission time zone of information of the slave device 3E1 of rank 5 that is rank 5. This 1 minute time slot is further subdivided into 60 time slots at 1 second intervals as described above, and the child device 3E1 transmits in 1 second of the time slot assigned corresponding to its own individual identification number. . The child device 3E1 includes information including its own individual identification number, availability of reception of time information, rank of time information (that is, reference time information of rank 5), and individual identification number of the relay device 42 of the transmission source. Send. The information of the rank 5 child device 3E1 is relayed by the repeater 42, the rank 3 child device 3C3, the rank 2 child device 3B2, and the rank 1 child device 3A2. That is, the information is added to the information of each child device transmitted at the transmission timing of each child device to be relayed and received by the parent device 2. One minute from 3:56 to 3:57 is a transmission time zone of information of the repeater 42 and the slave device 3D1 in rank 4. This 1 minute time zone is further subdivided into 60 time zones at 1 second intervals as described above, and the repeater 42 and the child device 3D1 are 1 second of the time zone assigned corresponding to their own individual identification numbers. Send to. One minute from 3:57 to 3:58 is a transmission time zone of information of the repeater 41 and the slave devices 3C1, 3C2, and 303 which are rank 3. This 1 minute time zone is further subdivided into 60 time zones at 1 second intervals as described above, and the repeater 41 and the slave devices 3C1, 3C2, 3C3 are assigned time corresponding to their own individual identification numbers. Transmission is performed in 1 second of the band.

  One minute from 3:58 to 3:59 is a transmission time zone of information of the slave devices 3B1 and 3B2 of rank 2 whose rank is 2. This 1-minute time zone is further subdivided into 60 time zones at 1-second intervals as described above, and the child devices 3B and 3B2 are assigned their own individual identification numbers (specific numbers between 1 and 60). Transmission is performed in one second of the corresponding time zone. The information of the rank 2 child devices 3B1 and 3B2 is received by the rank 1 child devices 3A1 and 3A2, added to the information of the child devices 3A1 and 3A2, and delivered to the parent device 2.

  The first child devices 3A1 and 3A2, which are the first rank, transmit information directly to the parent device 2 during the allotted 1 second of 1 minute from 3:59 to 4 o'clock. In this way, even if radio waves having the same frequency are used, there is no interference.

  The parent device 2 receives the reception status information from all the child devices 3 at 4 o'clock, and displays the reception status information on the display unit 19. Further, the reception status information is stored in the storage device and processed as necessary. From this displayed reception state, it is possible to confirm whether each child device 3 has actually received the time information to correct the time and the propagation path of the time information. If necessary, the repeater 4 is arranged. The reliability of the communication system 1 can be increased by relocating the slave device 3. In addition, each wireless IC tag included in the received information can display information collected or processed / processed in association with time information.

  In the embodiment, the decoder and the second decoder, and the power supply control unit and the second power supply control unit have different configurations, but two functions may be provided by the same configuration.

  By adopting such a configuration, when building a communication system in a state where wired communication and wireless communication are mixed, the time measurement of the same rank (link distance from the parent device) is constant regardless of the difference in communication media This can avoid the problem that the clock times of the slave devices 3 of the same rank vary.

  In the above embodiment, the wireless IC tag is shown as the slave device 3. However, the present invention is applicable to any other electronic device having a wireless communication function. For example, as shown in FIG. 8, a wireless device 5 (PDA, portable wireless device, notebook computer, laptop computer) having a communication circuit 501, a timer circuit 502, a memory 503, an input unit 504, a display unit 505, and a processor 506 Etc.), etc., and can be applied to various devices that do not mainly use timekeeping and timekeeping time.

  Furthermore, the number of slave devices constituting one wireless system, the width (period) of each channel when performing time division communication, the time required for uplink and downlink, etc. are also arbitrary, and the number of slave devices and channel detection It can be set as appropriate in consideration of the accuracy of the network and the period of time available for the downlink and uplink. For example, the parent device 2 transmits the reference time information at any timing in the rank 1 transmission time zone in FIG. 5, and the rank 1 to 59 child devices in the rank 2 to 60 transmission time zones in FIG. 5, respectively. 3 may transmit reference time information. Furthermore, the individual identification number does not need to be a number that is numeric information, and may be identification information for distinguishing each other. The setting method of rank (hierarchy order, transmission order) is also arbitrary.

In the above-described embodiment, two configurations for communicating with different types of communication paths having different communication speeds are arranged in one slave device 3, but communication is performed with any one type of communication path in one slave device. Only a circuit for performing the above may be arranged. In this case, the delay time is set in the delay time adjustment unit 75 in consideration of the communication time of other child devices arranged in the same rank.
In order to reduce power consumption, for example, one of a wireless circuit and a wired circuit may be set in a sleep state. For example, the processor 304 periodically performs wireless communication and wired communication, determines a communication route that can receive the time information having the highest rank, and thereafter receives a signal only through that route. Also good. Then, when information cannot be received regularly and / or continuously for a predetermined number of times, wireless communication and wired communication may be performed.

Further, the medium for wireless communication between apparatuses is not limited to radio waves, and may be light or ultrasonic waves.
Furthermore, in the above embodiment, the difference in transmission delay between wireless communication and wired communication is considered as a problem. However, the present invention can be widely applied when a plurality of types of signal transmission speed communication methods are mixed.
For example, when the parent device 2 and the child device 3A1 are connected at a transmission rate of xbps, and the parent device 2 and the child device 3A2 are connected at a transmission rate of ybps (x >> y), the child device The present invention is widely applicable when the time of 3A1 is delayed by a predetermined time and the time measured by the slave device 3A1 is adjusted to be synchronized with the time measured by the slave device 3A2.

  In the above embodiment, in order to facilitate understanding, each child device 3 includes a receiver and a decoder that are always on to receive and process commands and instructions generated at arbitrary timings. However, it is also possible to use the same receiver for downlink and uplink and for command reception. In this case, it is only necessary to tune and receive only the command signal after the rank control unit 35 outputs the rank information at the downlink or after the transmission is completed at the uplink. .

  In addition, it is arbitrary what kind of processing is performed in the communication system 1 as a whole or in each child device 3 using a timekeeping unit maintained at an accurate value. For example, if the child device 3 is a thermometer, for example, every time a predetermined time is measured, the measurement data of the temperature sensor is read and stored in the memory to take a temperature history at predetermined time intervals, If the child device 3 is a game machine such as a slot machine, for example, a history of coins inserted and discharged at predetermined time intervals can be obtained. In addition, for example, when there is a predetermined instruction / request from the outside (when the first trigger occurs), the requested processing is executed and the execution time is recorded together with the processing content, and the uplink is performed. The stored time information and processing contents may be wirelessly transmitted or output at the time or when there is an instruction / request from the outside (when the second trigger occurs). For example, if the child device 3 is a gas meter, the time is transmitted together with the usage amount data in response to a wireless request from the meter reading terminal, and the transmission information is recorded together with the ID of the requesting meter reading terminal. A history may be taken. For example, the timekeeping time is corrected, and the information collected in the uplink processing is transmitted.

1 is a schematic diagram of a communication system according to an embodiment of the present invention. FIG. 2 is a block diagram of the parent device shown in FIG. 1. FIG. 2 is a block diagram of the child device shown in FIG. 1. The block diagram of the communication function part of the subunit | mobile_unit shown in FIG. The time chart which shows the time allocation at the time of the downlink of the time information for time correction in the communication system of FIG. The time chart which shows the time allocation at the time of the uplink of the information of a child apparatus in the communication system of FIG. It is a figure which shows the structural example of the reception status information transmitted at the time of an uplink. The block diagram of the application example of the subunit | mobile_unit shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Communication system 2 Parent apparatus 3 Child apparatus 19 Display part 21, 31 Receiver 23, 33 Time adjustment part 24, 34 Time measuring part 27 Identification number memory | storage part 37 Individual identification number memory | storage part 35 Rank control part 28, 38 Transmitter 51, 52 Wired communication 51A, 52A Transmitter / receiver 61, 71 Serial signal encoder 62, 72 Transmitter / receiver 64, 74 Second decoder 75 Delay time adjustment unit

Claims (8)

A communication system comprising: a parent device that transmits time information; and a child device that receives the time information transmitted from the parent device and corrects the time measured by its own time measuring means based on the received time information. ,
The child device is
Data processing means for executing predetermined data processing based on the time measured by the time measuring means;
First receiving means for receiving time information by the first communication method;
Second receiving means for receiving time information in a second communication method having a communication time longer than that of the first communication method;
Delay means for delaying the time information received by the first receiving means by a predetermined time;
Selecting means for selecting one of the time information received by the first receiving means and the time information received by the second receiving means;
When the time information received by the second receiving means is selected by the selecting means, the timekeeping time is corrected based on the time information, and the time information received by the first receiving means is selected by the selecting means Sometimes the correcting means for correcting the time measured by the time measuring means based on the time information delayed by the delay means;
Means for transmitting time information for correcting the time of another child device based on the corrected timekeeping time;
A communication system comprising:   The communication system according to claim 1, wherein the second communication method is a wireless communication method, and the first communication method is a wired communication method.   The delay means gives a delay time corresponding to a time difference between a communication time of time information according to the second communication method and a communication time of time information according to the first communication method. Or the communication system of 2.   The selection means uses both the time information received by the first receiving means according to the first communication method and the reception of the time information received by the second receiving means according to the second communication method, and the reception state is good 4. The communication system according to claim 1, 2 or 3, wherein the time information of the other side is adopted.   The delay means delays the time information by a time such that the time measured by the time measuring means of a plurality of child devices located in the same order is substantially the same in the transmission order of the time information from the parent device. The communication system according to any one of claims 1 to 4, characterized in that:   The communication system according to claim 1, wherein the slave device includes a wireless tag or an information terminal.   The slave device is composed of a wireless tag having a data storage means and a package, and the data processing means responds to a predetermined trigger signal to the timekeeping information indicating the timekeeping time of the timekeeping means in the data storage means. Means for storing and processing the time information stored in the data storage means directly or by data and outputting the information to the outside wirelessly, and the package is made of a material capable of transmitting wireless signals and encloses the whole. The communication system according to any one of claims 1 to 6. Receiving means for receiving time information transmitted from another device;
Delay means for delaying and outputting the time information received by the receiving means for a predetermined time;
Correction means for correcting the time held by itself based on the time information delayed by the delay means;
Transmitting means for transmitting time information for correcting the time of another child device based on the corrected self time;
Data processing means for executing predetermined data processing based on the own time;
A communication apparatus comprising:

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