JP5836092B2 - Wireless communication apparatus, wireless communication system, and path construction method - Google Patents

Description

  The present invention relates to a wireless communication device, a wireless communication system, and a route construction method.

  Conventional route construction in wireless communication is realized by the following steps. First, a route from a transmission source to a destination via an intermediate terminal is searched by an AODV (Ad hoc On-Demand Distance Vector) algorithm, and a communication band on the communication route is reserved. Next, communication bandwidth information on the link path connecting adjacent intermediate terminals is stored in the intermediate terminal. Finally, information on the communication bandwidth that can be used at the time of response from the destination terminal to the transmission source terminal is collected and notified to the transmission source terminal. Thereby, the QoS (bandwidth) requested by the transmission source is satisfied (for example, see Patent Document 1).

  In another conventional route construction technique, first, the relay terminal counts the number of path connection request messages broadcast from the transmission source terminal, thereby quantitatively grasping the congestion degree of the relay terminal, and based on the count result. Set the relay probability of the path connection request message. Then, when a path connection request message is received, a method has been proposed in which relaying is selectively prohibited based on a set relay probability, thereby reducing communication band pressure due to the path request message (for example, Patent Document 2). reference).

International Publication No. 2003/062212 Japanese Patent Laid-Open No. 2004-64678

  In the specific low power radio, there is a communication mode in which a limit is set for transmission time per hour. For example, in the 950 MHz band specified in ARIB (Association of Radio Industries and Businesses) STD-T96, the transmission time per hour is longer in the communication mode where the antenna power exceeds 1 mW and 10 mW or less, and the carrier sense time is 128 μs or more. The total is defined as 360 seconds or less.

  However, the conventional route construction method does not consider the total transmission time per hour as described above. For this reason, there has been a problem that transmission is prohibited when the sum of transmission times per hour in the terminal exceeds the prescribed sum of transmission times per hour. Further, since transmission is prohibited, there are problems such as an increase in packet transmission delay and packet loss due to buffer overflow.

  The present invention has been made in view of the above, and constructs a route in which the sum of transmission times per unit time in each wireless communication device does not exceed the sum of transmission times per unit time specified, It is an object of the present invention to obtain a wireless communication device, a wireless communication system, and a route construction method that can avoid a state in which transmission is prohibited.

  In order to solve the above-described problems and achieve the object, the present invention provides a wireless communication apparatus that constitutes a communication system in which a total transmittable time that is a sum of transmission times per unit time is defined. When functioning as a periodic transmission device whose terminal transmission time sum, which is the sum of transmission times of the own device per unit time excluding the transfer time of data transmitted from the device, is known, transmitted from another periodic transmission device A reserved transmission time storage unit for storing a total of reserved transmission times, which is a sum of transmission times of the reserved device including the data transfer time, and a route information managed by the wireless communication device as a destination from the own device When building a route to a destination device, a route management unit that stores the terminal transmission time sum in a route request packet that requests route construction to the destination device and transmits the route management packet, and does not set the own device as the destination device When the route request packet transmitted from the periodic transmission device is received, the total value of the terminal transmission time sum stored in the route request packet and the reserved transmission time sum stored in the reserved transmission time storage unit is A transmission time management unit that determines whether or not the total transmittable time is exceeded, and the route management unit sends the received route request packet to the destination device based on a determination result by the transmission time management unit The transmission time management unit receives the route response packet transmitted from the destination device as a response to the route request packet, the route request packet is added to the total of the reserved transmission time. The total terminal transmission time stored in is added.

  According to the present invention, a route in which the total transmission time per unit time in each wireless communication apparatus does not exceed the total transmission time per unit time is established, and a state where transmission is prohibited is avoided. There is an effect that can be.

FIG. 1 is a diagram illustrating a functional configuration example of a terminal according to the first embodiment. FIG. 2 is a diagram illustrating a network configuration example for explaining the route construction method according to the first embodiment. FIG. 3 is a chart showing an example of the operation when the terminal constructs a new route. FIG. 4 is a diagram illustrating a functional configuration example of the terminal according to the second embodiment. FIG. 5 is a diagram illustrating a network configuration for explaining the route construction method according to the second embodiment. FIG. 6 is a chart showing an example of the operation when the regular transmission terminal and the irregular transmission terminal transmit data. FIG. 7 is a chart showing an example of an operation when the terminal according to the third embodiment transmits data. FIG. 8 is a chart showing an example of an operation when the terminal according to the fourth embodiment transmits data. FIG. 9 is a diagram illustrating an example of a network configuration for explaining the route changing method according to the fifth embodiment. FIG. 10 is a chart showing an example of an operation when changing the transmission path of irregular data. FIG. 11 is a diagram illustrating a network configuration example for explaining the data transmission method according to the sixth embodiment. FIG. 12 is a chart showing an example of the transmission mode switching operation.

  Hereinafter, embodiments of a wireless communication device, a wireless communication system, and a path construction method according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram illustrating a functional configuration example of a first embodiment of a terminal according to the present invention. In the present embodiment, a terminal will be described as an example of a wireless communication apparatus according to the present invention. As shown in FIG. 1, the terminal of this embodiment includes a control unit 1, a radio unit 2, an antenna 3, a route management unit 4, a transmission time management unit 5, a route storage unit 6, an actual transmission time storage unit 7, and a reservation. A transmission time storage unit 8 is provided.

  The antenna 3 is an antenna for performing wireless communication with another terminal or a sink, receives a transmission signal from the wireless unit 2 as a radio wave, and passes the received signal to the wireless unit 2. The radio unit 2 performs modulation or the like based on the transmission data received from the control unit 1 to generate a transmission signal, and passes the reception data obtained by demodulating the reception signal or the like to the control unit 1. The control unit 1 controls transmission / reception data, passes transmission data to the radio unit 2, and passes received data to the path management unit 4 or the transmission time management unit 5 depending on the received data type. The route management unit 4 performs route processing such as route construction and route change. The route storage unit 6 is storage means for storing the route constructed by the route management unit 4 as route information. The transmission time management unit 5 manages prescribed transmission time restrictions. The actual transmission time storage unit 7 is a storage means for storing the time taken for actual transmission (actual transmission time), and particularly stores the sum of actual transmission times per unit time (one hour). The actual transmission time for each unit time may be obtained by adding the transmitted time and resetting the value for each unit time, or storing the cumulative transmission time without resetting the value for each unit time. Alternatively, a difference from the previous unit time (for example, a difference between the value at the reference time point and the value before the unit time) may be obtained at the time of reference, and this difference may be used as the actual transmission time. The reserved transmission time storage unit 8 is a storage unit for storing a total of reserved transmission times per hour (reserved transmission time total) including transfer of data received from a terminal on a route that is known in advance. .

  When transmitting the data, the control unit 1 inquires of the transmission time management unit 5 whether the transmission time necessary for data transmission remains, and the transmission time management unit 5 stores the actual transmission stored in the actual transmission time storage unit 7. Whether transmission is possible is determined based on the time and the total available transmission time. Specifically, for example, the transmission time management unit 5 determines that transmission is possible if the value obtained by subtracting the actual transmission time from the total transmission time is equal to or greater than a certain value. Further, when data is transmitted from the own terminal, the control unit 1 measures the time taken for transmission, and updates the information stored in the actual transmission time storage unit 7 based on the measurement result.

  FIG. 2 is a diagram illustrating an example of a network configuration for explaining the route construction method according to the present embodiment. The network configuration in FIG. 2 is an example, and the network configuration to which the route construction method of the present embodiment is applied is not limited to the example in FIG. The network (wireless communication system) illustrated in FIG. 2 includes a sink 20 and terminals 21 to 26. Terminals 21 to 26 are terminals of the present embodiment shown in FIG. The sink 20 may be the terminal of the present embodiment shown in FIG. 1 or may be a wireless communication device having another configuration.

  The terminal 21 is a terminal that newly joins the network, and the terminals 22, 23, 24, 25, and 26 are terminals that have already joined the network. The sink 20 is a transmission destination of data transmitted by each terminal. Note that data from the terminals 22, 23, 24, 25, and 26 is delivered to the sink 20 through the path indicated by the arrow.

  Each terminal transmits in a transmission mode in which the total transmittable time is defined. In this specification, “total transmission time” means the sum of the upper limit values of transmission time per unit time (transmission time), and in this specification, the total transmission time per hour. Sum. Here, the total transmission time is 360 seconds. Note that the total transmittable time is not limited to this, and can be changed to any value as a threshold value.

  In each terminal, the transmission data amount of the own terminal per unit time, the number of transmissions, etc. are known, the terminal transmission time sum is known in advance, and the terminal transmission time sum is held. In this specification, “terminal transmission time sum” means the sum of terminal transmission times per unit time excluding transfer of packets received from other terminals, and in this specification, packets received from other terminals. The total transmission time of the terminal per hour excluding the transfer of. Here, the total terminal transmission time of the terminals 21, 22, 23, 24, 25, and 26 is 100 seconds, respectively. Here, for simplicity, the terminal transmission time sums of the terminals 21, 22, 23, 24, 25, and 26 are set to the same value, but the terminal transmission time sums of the terminals 21, 22, 23, 24, 25, and 26 are respectively May be different.

  The reservation transmission time storage unit 8 of each terminal stores the total reservation transmission time. In this specification, “reserved transmission time sum” means the sum of transmission times of terminals per unit time known to be transmitted in advance, including the transfer time of packets received from other terminals. In the document, it is assumed that the total transmission time of the terminal per hour known to be transmitted in advance, including the transfer time of the packet received from the other terminal. When data transmission is performed in the direction indicated by the solid line arrow in FIG. 2, the total reserved transmission time is 100 seconds in the reserved transmission time storage unit 8 of the terminal 22, and the reserved transmission time storage unit 8 of the terminal 23 is in the reserved transmission time storage unit 8. The total reserved transmission time including the packet transfer from the terminal 22 is 200 seconds, the reserved transmission time storage unit 8 of the terminal 24 is 100 seconds, and the reserved transmission time storage unit 8 of the terminal 25 is the terminal 24. 26, the total reserved transmission time is 300 seconds including the packet transfer from 26, and the reserved transmission time storage unit 8 of the terminal 26 stores the total reserved transmission time as 100 seconds.

  In the network configuration shown in FIG. 2, the operation when a terminal 21 is newly added to construct a route will be described with reference to FIG. FIG. 3 is a chart showing an example of the operation when the terminal 21 constructs a new route. In order to construct a route to the sink 20, the route management unit 4 of the terminal 21 generates an RREQ (Route Request) that is a route construction request and broadcasts it via the control unit 1, the radio unit 2, and the antenna 3 (step S1). ). The RREQ includes a SOURCE address (here, the address of the terminal 21), a DESTINATION address (here, the address of the sink 20), a SENDER address (here, the address of the terminal 21), a RECEIVER address (here, broadcast), a terminal The total transmission time (here, 100 seconds) and the sequence number (here, 0) are included. RREQ is broadcast and received by terminals 22 and 24 adjacent to terminal 21.

  The terminal 22 and the route management unit 4 of the terminal 24 that have received the RREQ via the antenna 3, the radio unit 2 and the control unit 1 are included in the received RREQ to the transmission time management unit 5 via the control unit 1 (or directly). Inquire whether the total terminal transmission time can be reserved. Based on this inquiry, the transmission time management unit 5 of the terminal 22 stores the total reserved transmission time (here, 100 seconds) stored in the reserved transmission time storage unit 8 and the total terminal transmission time included in the RREQ (here, 100 seconds) is calculated, and since this total time is equal to or less than the total transmission time (360 seconds in this case), it is determined that reservation is possible. Similarly, the transmission time management unit 5 of the terminal 24 adds the total of the reserved transmission time (here, 100 seconds) stored in the reserved transmission time storage unit 8 and the total of the terminal transmission times (100 seconds) included in the RREQ. Is less than or equal to the total transmittable time (here, 360 seconds), so that it is determined that reservation is possible. The route management unit 4 of the terminals 22 and 24 converts the RREQ having the SOURCE address (in this case, the address of the terminal 21) as the transmission source based on the information stored in the received RREQ (here, the terminal). 21) is received. The transmission time management unit 5 of the terminals 22 and 24 stores the terminal transmission time total included in the RREQ of the SOURCE address (here, the address of the terminal 21) in association with the SOURCE address.

  The terminal 22 that has determined that the total terminal transmission time included in the RREQ can be reserved changes the SENDER address of the RREQ to its own terminal address, increments the sequence number, and transfers it by broadcast (step S2). The terminal 23 receives the RREQ transferred by the terminal 22. The route management unit 4 of the terminal 23 that has received the RREQ inquires of the transmission time management unit 5 whether the terminal transmission time total included in the received RREQ can be reserved, as with the terminals 22 and 24 in step S1. The transmission time management unit 5 of the terminal 23 is the total time of the reserved transmission time total (here, 200 seconds) stored in the reserved transmission time storage unit 8 and the terminal transmission time total (here, 100 seconds) included in the RREQ. Is less than or equal to the total transmittable time (here, 360 seconds), so that it is determined that reservation is possible. Note that the route management unit 4 of the terminal 23 stores that the RREQ having the SOURCE address (here, the address of the terminal 21) is received from the SENDER address (here, the address of the terminal 22), and the transmission time The management unit 5 stores the terminal transmission time total included in the RREQ of the SOURCE address (here, the address of the terminal 21) in association with the SOURCE address.

  The terminal 24 that has determined that the total terminal transmission time included in the RREQ can be reserved changes the SENDER address of the RREQ to its own terminal address, increments the sequence number, and forwards it by broadcast (step S3). . The terminal 25 receives the RREQ transferred by the terminal 24. The path management unit 4 of the terminal 25 that has received the RREQ inquires of the transmission time management unit 5 whether the terminal transmission time total included in the received RREQ can be reserved in the same manner as the terminals 22 and 24 in step S1. The transmission time management unit 5 of the terminal 25 sums up the reserved transmission time total (here, 300 seconds) stored in the reserved transmission time storage unit 8 and the terminal transmission time total (here, 100 seconds) included in the RREQ. Since the time exceeds the total transmittable time (here, 360 seconds), it is determined that the reservation is impossible, and the RREQ is discarded.

  The terminal 23 that has determined that the total terminal transmission time included in the RREQ can be reserved changes the SENDER address of the RREQ to its own terminal address, increments the sequence number, and transfers it by broadcast (step S4). The sink 20 receives the RREQ transferred by the terminal 23.

  The sink 20 waits for a certain period of time after receiving the first RREQ. If the source (SOURCE address) does not receive the same RREQ, the sink 20 sends RREP (Route Reply) to the source (SOURCE address) of the RREQ. Transmit (step S5). If one or more RREQs having the same RREQ and source (SOURCE address) are received while waiting for a certain period of time, one of these received RREQs is selected and RREP (Route Reply) is transmitted. . This selection method is arbitrary, such as one with a small sequence number or one with a fast reception order. In the example of FIG. 3, since only the RREQ from the terminal 23 is received, the RREP transmits the RREP to the RREQ received from the terminal 23.

  RREP includes a SOURCE address (here, the address of the sink 20), a DESTINATION address (here, the address of the terminal 21), a SENDER address (here, the sink 20), and a RECEIVER address (here, the address of the terminal 23). Including. In the RECEIVER address, the SENDER address of the selected RREQ (or the RREQ if only one RREQ is received) is set as the RECEIVER address. The RREP is unicasted to the RECEIVER address (in this case, the address of the terminal 23).

  The route management unit 4 of the terminal 23 that has received the RREQ updates the route information stored in the route storage unit 6 based on the information included in the RREP. Specifically, the next hop address when transmitting to the address of the sink 20 included as the SOURCE address is the address of the sink 20 included as the SENDER address, and the next hop address when transmitting to the address of the terminal 21 included as the DESTINATION address. The hop address is the SENDER address (the address of the terminal 22) stored when the RREQ corresponding to RREP is received. Alternatively, the path information is held for each combination of transmission / reception terminals, and the next hop address when transmitting data from the address of the terminal 21 included as the DESTINATION address to the address of the sink 20 included as the SOURCE address is included as the SENDER address. SENDER address (address of terminal 22) stored at the time of RREQ reception as the next hop address when data from the address of sink 20 included as the SOURCE address is transmitted to the address of terminal 21 included as the DESTINATION address And Note that the route information storage method is not limited to this.

  The transmission time management unit 5 of the terminal 23 adds the terminal transmission time total (100 seconds in this case) of the terminal 21 stored at the time of receiving the RREQ to the reserved transmission time total stored in the reserved transmission time storage unit 8 and adds The later value is stored in the reserved transmission time storage unit 8 as the total reserved transmission time.

  In addition, the route management unit 4 of the terminal 23 changes the SENDER address of the RREP to the address of its own terminal, changes the RECEIVER address to the SENDER address (terminal 22) stored at the time of receiving the RREQ, and unicasts the RREP to the terminal 22 Transmit (step S6). The route management unit 4 of the terminal 22 that has received the RREP updates the information in the route storage unit 6 based on the information included in the RREP, similarly to the terminal 23 that has received the RREP. Also, the transmission time management unit 5 updates the information in the reserved transmission time storage unit 8 in the same manner as the terminal 23 that has received RREP.

  Further, the route management unit 4 of the terminal 22 unicasts the RREP to the terminal 21 in the same manner as the terminal 23 that has received the RREP (step S7). The route management unit 4 of the terminal 21 that has received the RREP updates the route information stored in the route storage unit 6 based on the information included in the RREP. Specifically, the next hop of data transmission to the address of the sink 20 included as the SOURCE address is set as the address of the terminal 22 included as the SENDER address. Also, the transmission time management unit 5 of the terminal 21 stores its own terminal transmission time total (here, 100 seconds) as the reserved transmission time total in the reserved transmission time storage unit 8.

  In the above description, the terminal that transmits the RREQ (in this case, the terminal 21) stores the total terminal transmission time in the RREQ, and each terminal that has received the RREQ stores the total terminal transmission time of the terminal 21. However, at the time when the RREQ is received, each terminal may notify the terminal 21 of the total transmission time of the terminal 21 by REPP. In this case, the destination of RREQ (here, sink 20) stores the terminal transmission time sum of terminal 21 in RREP and transmits it, and each terminal that has received RREP extracts the terminal transmission time sum of terminal 21 from RREP. To the total reserved transmission time.

  Further, the total transmittable time as the threshold may be set to a value lower than a predetermined value in consideration of a response to retransmission or data transmission. Further, the route information stored in the route storage unit 6 may be provided with an expiration date, and the route information may be deleted after a predetermined time.

  Further, although the RREQ is always broadcast in the present embodiment, when a route up to the DESTINATION address has already been constructed, it may be transmitted by unicast to the constructed route.

  As described above, in the present embodiment, when there is a route construction, it is confirmed whether or not the total transmission time exceeds the transmission by the route constructed by the new route construction in each terminal, The route is built when the total transmission time is not exceeded. Thereby, it is possible to avoid a transmission prohibition state due to an excess of the total transmission time. Further, by avoiding the transmission prohibited state, an increase in packet transmission delay and packet loss due to buffer overflow can be reduced.

Embodiment 2. FIG.
FIG. 4 is a diagram illustrating a functional configuration example of the terminal according to the second embodiment of the present invention. As shown in FIG. 2, the terminal according to the present embodiment adds a periodic transmission time storage unit 9 and an irregular transmission time storage unit 10 instead of the reserved transmission time storage unit 8 of the terminal according to the first embodiment. . Constituent elements having the same functions as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and redundant descriptions are omitted. Hereinafter, a different part from Embodiment 1 is demonstrated.

  In Embodiment 1, each terminal constructs a route that does not exceed the total transmittable time, assuming that the terminal total transmission time of the terminal itself is known. For terminals that regularly transmit a certain amount of data, the total terminal transmission time is known, but for terminals that perform irregular transmissions or terminals that do not know whether or not to perform regular transmissions. The total terminal transmission time cannot be obtained in advance. In this embodiment, in a network in which terminals having a known total terminal transmission time (periodic transmission terminal (periodic transmission apparatus)) and terminals having an unknown total terminal transmission time (irregular transmission terminal (irregular transmission apparatus)) are mixed. An embodiment of route construction and data transmission will be described.

  Similar to the reserved transmission time storage unit 8 of FIG. 1, the periodic transmission time storage unit 9 stores the sum of the reserved transmission times per hour for the periodic transmission terminals on a route that is known in advance. The irregular transmission time storage unit 10 stores a transmission time (including transfer) per hour of a packet transmitted by the irregular transmission terminal.

  FIG. 5 is a diagram showing a network configuration for explaining the route construction method of the present embodiment. Terminals 31-34 are the terminals of the present embodiment shown in FIG. The sink 30 may be the terminal according to the present embodiment illustrated in FIG. 1 or may be a wireless communication device having another configuration. The terminals 33 and 34 are regular transmission terminals, and the terminals 31 and 32 are irregular transmission terminals. Data from each terminal is delivered to the sink 30 according to the path indicated by the arrow.

  Each terminal manages the total transmittable time by dividing it into a regular transmittable time total and an irregular transmittable time total. In this specification, “total periodical transmission possible time” means the total transmission time per unit time allocated for regular transmission out of the total transmission time per unit time specified. In the document, the sum of the transmission time per hour allocated to the regular transmission. Also, in this specification, “total irregular transmission possible time” means the total transmission time per unit time allocated for irregular transmission out of the total transmission time per specified unit time. In this specification, the sum of transmission times per hour allocated to irregular transmission is used. In other words, the sum of the total transmittable time and the total non-periodic transmittable time is the total transmittable time. The ratio of the total periodical transmittable time and the total periodical transmittable time is an arbitrary value such that the sum of the total periodical transmittable time and the total periodical transmittable time is less than or equal to the total transmittable time.

  The regular transmission time summation unit 9 stores the total regular transmission time. In this specification, “total periodic transmission time” means the total of periodic packet transmission times per unit time that is known to be transmitted in advance, including the transfer time of periodic packets received from other periodic transmission terminals. is there. That is, the total periodic transmission time corresponds to the total reserved transmission time described in the first embodiment for the periodic transmission terminal. In this specification, the sum of the periodic transmission times is the sum of the regular packet transmission times per hour that is known to be transmitted in advance, including the transfer time of the regular packets received from other regular transmission terminals.

  The irregular time storage unit 10 stores the irregular transmission time sum. In this specification, “sum of irregular transmission times” means the total sum of irregular packet transmission times actually transmitted per unit time, including the transfer time of irregular packets received from other irregular transmission terminals. It is. That is, the irregular transmission time total corresponds to the reserved transmission time total described in the first embodiment for the irregular transmission terminal. In this specification, the sum of the periodic transmission times is the sum of the transmission times of actually transmitted irregular transmission packets per hour, including the transfer time of irregular packets received from other irregular transmission terminals. Here, the irregular packet indicates a packet whose transmission source is the irregular transmission terminal, and may actually include a regular transmission packet transmitted by the irregular transmission terminal.

  In the periodic transmission terminal, the initial value of the total periodic transmission time (a state in which a route is not constructed to transfer data transmitted from other devices) is set to the terminal transmission time total of its own device, In the irregular transmission terminal, the initial value of the total periodic transmission time is set to a predetermined value (for example, 0). The total irregular transmission time is set to a predetermined value (for example, 0) for both the regular transmission terminal and the irregular transmission terminal.

  When the terminal 33, which is a regular transmission terminal, establishes a route to the sink 30, the terminal 33 transmits an RREQ as in the first embodiment. Note that a flag for distinguishing between a regular transmission terminal and an irregular transmission terminal is set (stored) in RREQ. Similarly to the first embodiment, the transmission time management unit 5 of the terminal 34 that has received the RREQ in which the flag indicating the periodic transmission terminal is set, sums the periodic transmission times stored in the periodic transmission time storage unit 9 (the embodiment) 1) corresponding to the total number of reserved transmission times) and the total time of the terminal transmission times included in the RREQ and the total amount of time that can be periodically transmitted. That is, it is determined whether or not the total time of the total periodic transmission time and the total terminal transmission time included in the RREQ exceeds the total periodic transmission available time. If it is determined that transfer is possible, the RREQ is transferred toward the sink 30.

  The sink 30 that has received the RREQ transmits the RREP as a response in the same manner as in the first embodiment. The terminal 34 that has received the RREP performs the same operation as in the first embodiment, and transfers the RREP to the terminal 33. When receiving the RREP, the terminal 33 performs the same operation as in the first embodiment. The periodic transmission terminals (in this case, the terminal 33 and the terminal 34) that have received the RREP update the route information and the reserved transmission time total based on the terminal transmission time total of the terminal 33, as in the first embodiment. However, at this time, the periodic transmission time total stored in the periodic transmission time storage unit 9 is updated as the reserved transmission time total.

  When the terminal 31 that is an irregular transmission terminal establishes a route to the sink 30, the terminal 31 transmits an RREQ as in the first embodiment. Note that a flag for distinguishing between a regular transmission terminal and an irregular transmission terminal is set (stored) in RREQ. In addition, when a terminal which is an irregular transmission terminal transmits, RREQ does not include the terminal transmission time sum. The terminal 32 that has received the RREQ in which the flag indicating the irregular transmission terminal is set performs the same operation as in the first embodiment except for the operation of the transmission time management unit 5 and transmits the RREQ to the sink 30. When the sink 30 receives the RREQ, the sink 30 transmits the RREP to the terminal 31 as in the first embodiment.

  The terminal 32 that has received the RREP transmits the RREP to the terminal 31 by performing the same operation as in the first embodiment except for the operation of the transmission time management unit 5. The terminal 31 performs the same operation as in the first embodiment except for the operation of the transmission time management unit 5. That is, the terminal 31 and the terminal 32 update the route information, but do not perform processing based on the total terminal transmission time.

  The operation when the terminal 33 which is the regular transmission terminal and the terminals 31 and 32 which are the irregular transmission terminals shown in FIG. 5 transmit data will be described with reference to FIG. FIG. 6 is a chart showing an example of operations when data is transmitted from the terminal 33 which is a regular transmission terminal and the terminals 31 and 32 which are irregular transmission terminals. In this embodiment, a flag indicating that the data is regular data is stored in the data transmitted from the regular transmission terminal, and a flag indicating that the data is irregular data is stored in the data transmitted from the irregular transmission terminal. To do.

  When transmitting irregular data from the terminal 32 which is an irregular transmission terminal, the transmission time management unit 5 of the terminal 32 calculates a transmission time necessary for transmission of the irregular data to be transmitted, and the calculated transmission time and irregular It is determined whether the sum of the irregular transmission time sums stored in the transmission time storage unit 10 exceeds the irregular transmission possible time sum. Here, it is determined that it does not exceed, a flag indicating irregular data is stored in the irregular data to be transmitted, and is transmitted to the terminal 34 (step S11).

  The transmission time management unit 5 of the terminal 32 that has transmitted the irregular data adds the time required for the irregular data transmission to the irregular transmission time sum stored in the irregular transmission time storage unit 10. It is assumed that the total irregular transmission time stored in the irregular transmission time storage unit 10 is set to 0, for example, in the initial state. The transmission time management unit 5 of the terminal 34 that has received the irregular data from the terminal 32 calculates a transmission time necessary for transmitting the irregular data to be transferred, and is recorded in the calculated transmission time and the irregular transmission time storage unit 10. It is determined whether or not the sum of the total irregular transmission times exceeds the total irregular transmission time. The terminal 34 that has determined that the total non-periodic transmission possible time does not exceed is transferred to the sink 30 (step S12), and the transmission time management unit 5 of the terminal 34 is required for the irregular data transmission (transfer). Is added to the sum of the irregular transmission times stored in the irregular transmission time storage unit 10.

  Even when the irregular data is transmitted from the terminal 31, the terminal 31 performs the determination in the transmission time management unit 5 and transmits the data to the sink 30 similarly to the terminal 32 in step S11 (step S13). When receiving the irregular data from the terminal 31, the terminal 32 and the terminal 34 make the determination in the transmission time management unit 5 and transfer it to the sink 30 (steps S14 and S15) in the same manner as the terminal 34 in step S12.

  Subsequently, when transmitting irregular data from the terminal 32, the transmission time management unit 5 makes a determination in the same manner as in step S11, and transmits it to the sink 30 (step S16). Here, the transmission time management unit 5 of the terminal 34 that has received the irregular data from the terminal 32 transmits the transmission time necessary for transmission of the irregular data to be transferred and the irregular transmission recorded in the irregular transmission time storage unit 10. Suppose that it is determined that the sum of time sums exceeds the sum of times that can be transmitted irregularly. In this case, the terminal 34 stops the transfer of irregular data and discards the received irregular data. Alternatively, the received irregular data is stored in a buffer, and is transmitted after there is room to transmit irregular data in the total irregular transmission time.

  On the other hand, if the regular data is transmitted from the terminal 33 which is the regular transmission terminal in this state (step S17), the irregular data transmission is prohibited in the terminal 34, but the transmission time for the regular data is the route. Separately secured at the time of construction. For this reason, the terminal 34 can transfer the regular data even when the irregular data transmission is prohibited, and the regular data received from the terminal 33 is transferred to the sink 30 (step S18). Note that the irregular transmission time total is reset to 0 each time a unit time (one hour in this case) defining the irregular transmission available time total elapses, for example. Also, without resetting the irregular transmission time sum every time the unit time elapses, a difference from the previous unit time (for example, the difference between the value at the reference time and the value before the unit time) is obtained, and this difference is calculated. It may be an actual irregular transmission time.

  As described above, in the present embodiment, the total transmittable time is managed by dividing it into the total periodical transmittable time and the total non-periodic transmittable time, and the periodic transmission terminal is transmitted at the time of route construction as in the first embodiment. Reserve (schedule) time, and for non-regular transmission terminals, do not reserve the transmission time when constructing the route, and add the total transmission time of data transmitted during data transmission and the total irregular transmission possible time The transmission time was managed based on this. For this reason, even when the transmission amount by the irregular transmission terminal increases, it is possible to avoid the influence on the communication of the regular transmission terminal.

Embodiment 3 FIG.
FIG. 7 is a chart showing an example of an operation when the terminal according to the third embodiment of the present invention transmits data. The configuration of the terminal according to the present embodiment is the same as the configuration of the terminal according to the second embodiment shown in FIG. Hereinafter, a different part from Embodiment 2 is demonstrated.

  The network configuration of the present embodiment is the same as the configuration shown in FIG. 5 of the second embodiment. Similarly to the second embodiment, the terminals 33 and 34 are regular transmission terminals, and the terminals 31 and 32 are irregular transmission terminals, and data from each terminal is delivered to the sink 30 along the path of the arrow.

  In the second embodiment, the total transmittable time in each terminal is divided into the total periodical transmittable time and the total periodical transmittable time so that the periodic transmission terminal can be protected even when the transmission amount of the irregular transmission terminal is large. However, in the present embodiment, an operation for changing the ratio of the total periodical transmittable time and the total periodical transmittable time will be described.

  As shown in FIG. 7, when transmitting irregular data from the terminal 31, it is transmitted to the sink 30 via the terminals 32 and 34 in the same manner as in steps S13 to S15 of the second embodiment (steps S21 to S21). S26). Here, the transmission time management unit 5 of the terminal (here, the terminal 34) that directly transmits data to the sink 30 is an irregular transmission terminal (non-periodic transmission terminal) that transmits irregular data to the sink 30 via itself. The total sum of irregular data transmission times in a certain period for each irregular transmission terminal of the transmission source) is measured. Whether or not the own terminal is a terminal that directly transmits data to the sink 30 can be determined by referring to the route information stored in the route storage unit 6.

  In the transmission time management unit 5 of the terminal 34, when there is an irregular transmission terminal in which the sum of irregular data transmission times in a certain period exceeds the threshold, transmission that shifts from the regular transmission possible time total to the irregular transmission possible time total. Set the possible time (change time). In other words, the change time is subtracted from the total periodical transmission possible time, and the change time is added to the total irregular transmission possible time. Although the change time is arbitrary, the total periodical transmission time after the ratio change is set to be equal to or greater than the total periodical transmission time stored in the periodical transmission time storage unit 9. Here, it is assumed that the sum of the irregular data transmission times of the terminal 31 exceeds the threshold. The transmission time management unit 5 of the terminal 34 sends the ratio change request packet storing the terminal address of irregular transmission exceeding the threshold (here, the address of the terminal 31) and the modification time to the terminal of irregular transmission exceeding the threshold. It transmits to (here, terminal 31) (step S27).

  The transmission time management unit 5 of the terminal 32 that has received the ratio change request packet, sums up the periodical transmittable time after reflecting the change time included in the ratio change request packet (total periodical transmittable time after subtracting the change time) ) Is equal to or greater than the sum of the periodic transmission times stored in the periodic transmission time storage unit 9. If the terminal 32 determines that the total periodical transmittable time after reflecting the change time is equal to or greater than the total periodical transmission time stored in the periodical transmission time storage unit 9, the terminal 32 transfers the ratio change request packet to the terminal 31 (step S28). ). When the terminal 32 determines that the total periodical transmittable time after reflecting the change time is not equal to or greater than the total periodical transmission time stored in the periodical transmission time storage unit 9, the terminal 32 discards the ratio change request packet.

  The transmission time management unit 5 of the terminal 31 that has received the ratio change request packet, in the same manner as the terminal 32, stores the total periodical transmittable time after reflecting the change time included in the ratio change request packet in the periodic transmission time storage unit 9. It is determined whether or not the sum of the stored periodic transmission times is exceeded. When it is determined that the total periodical transmittable time after reflecting the change time exceeds the total periodical transmission time stored in the periodical transmission time storage unit 9, the transmission time management unit 5 of the terminal 31 includes the ratio change request packet. The change time to be reflected is reflected in the total amount of time that can be sent regularly and the total time that can be sent irregularly. Further, the transmission time management unit 5 of the terminal 31 transmits a rate change confirmation packet as a response (step S29).

  The reception time management unit 5 of the terminal 32 that has received the rate change confirmation packet, like the terminal 31, reflects the change time included in the rate change request packet in the total periodical transmittable time and the total periodical transmittable time. 32 transfers the rate change confirmation packet to the terminal 34 (step S30). Similarly, the reception time management unit 5 of the terminal 34 that has received the ratio change confirmation packet reflects the change time determined by the terminal itself in the total periodical transmittable time and the total periodical transmittable time.

In this embodiment, the terminal 34 has received the ratio change confirmation packet. However, if the terminal 34 has not received the ratio change confirmation packet for a predetermined time, the terminal 34 determines that the ratio cannot be changed. Further, when it is determined that the ratio cannot be changed, the terminal 34 may not transmit a new ratio change request packet for a certain period.

  Further, in this embodiment, it is determined whether or not the rate change is successful based on the presence or absence of the rate change confirmation packet, but the terminal that has determined that the change is not possible transmits a rate change rejection packet to the terminal 34. Also good.

  In the present embodiment, the terminal that directly transfers data to the sink 30 determines the rate change. However, the sink 30 may perform the same determination and transmit the rate change request packet.

  Further, when the transmission time of the irregular data in the measured fixed period falls below the threshold, it is also possible to transmit a ratio change request packet that increases the total periodical transmission available time. The operations of the present embodiment other than those described above are the same as those of the second embodiment.

  As described above, in the present embodiment, the ratio between the total periodical transmittable time and the total periodical transmittable time is appropriately changed. For this reason, the same effect as in the second embodiment can be obtained, and there is a margin in the total amount of time that can be transmitted regularly, but there is no room in the total amount of time that can be transmitted irregularly. Although there is a margin, it is possible to avoid a state in which transmission is not possible because there is no margin in the total periodical transmission time.

Embodiment 4 FIG.
FIG. 8 is a chart showing an example of operation when the terminal according to the fourth embodiment of the present invention transmits data. The configuration of the terminal according to the present embodiment is the same as the configuration of the terminal according to the second embodiment shown in FIG. Hereinafter, a different part from Embodiment 2 is demonstrated.

  In the second embodiment, the total transmittable time in each terminal is divided into the total periodical transmittable time and the total periodical transmittable time so that the periodic transmission terminal can be protected even when the transmission amount of the irregular transmission terminal is large. However, this embodiment shows an embodiment in which a terminal registered as an irregular transmission terminal is changed to a regular transmission terminal.

  The network configuration of the present embodiment is the same as the configuration shown in FIG. 5 of the second embodiment. Similarly to the second embodiment, the terminals 33 and 34 are regular transmission terminals, and the terminals 31 and 32 are irregular transmission terminals, and data from each terminal is delivered to the sink 30 along the path of the arrow. An operation when the terminal 31 registered as an irregular transmission terminal is changed to a regular transmission terminal from this state will be described.

  As shown in FIG. 8, when transmitting irregular data from the terminal 31, it is transmitted to the sink 30 via the terminals 32 and 34 in the same manner as steps S13 to S15 of the second embodiment (steps S31 to S31). S36). Here, the transmission time management unit 5 of the terminal (here, the terminal 34) that directly transmits data to the sink 30 transmits the irregular data to the sink 30 via itself as in the third embodiment. With respect to the transmitting terminal, the total sum of the irregular data transmission times in a certain period (a unit time for defining a transmittable time, here 1 hour) for each irregular transmission terminal (transmission source irregular transmission terminal) is measured. The transmission time management unit 5 of the terminal 34 repeats this measurement a plurality of times, and when the difference between the measured values is within a threshold value, determines that the irregular transmission terminal is to be changed to a regular transmission terminal. Whether or not the own terminal is a terminal that directly transmits data to the sink 30 can be determined by referring to the route information stored in the route storage unit 6.

  When determining the type change from the irregular transmission terminal to the regular transmission terminal, the transmission time management unit 5 of the terminal 34 adds the measured average time of the irregular data transmission times to the total periodical transmission possible time, The average time is subtracted from the total irregular transmission available time, and the average time is added to the regular transmission time total in the regular transmission time storage unit 9.

  When the terminal 34 determines that the type change is to be performed, it transmits a type change request packet to the terminal to be changed (here, the terminal 31) (step S37). Note that the average time of the sum of the irregular data transmission times is added to the type change request packet. The transmission time management unit 5 of the terminal 32 that has received the type change request packet adds the average time included in the received type change request packet to the total periodical transmittable time, and calculates the average time from the total irregularly transmittable time. The average time is subtracted and added to the sum of the periodic transmission times in the periodic transmission time storage unit 9.

  The terminal 32 that has received the type change request packet transfers the type change request packet to the terminal 31 (step S38). The transmission time management unit 5 of the terminal 31 that has received the type change request packet adds the average time included in the received type change request packet to the total periodical transmittable time, and subtracts the average time from the irregular period transmittable time total Then, the average time is added to the sum of the regular transmission times in the regular transmission time storage unit 9. Further, the terminal 31 regards the terminal as a regular transmission terminal, and transmits transmission data to which a flag indicating the regular data is added at the time of data transmission.

  Note that the sink 30 may similarly transmit a type change request packet instead of a terminal that directly transmits data to the sink 30. Further, the terminal (in this case, the terminal 34) or the sink 30 that directly transmits data to the sink 30 measures the periodical data transmission time for a certain period of the terminal whose terminal type is changed to the periodical transmission terminal, and the periodical data transmission time is a threshold value. In the case of exceeding, it is possible to change the type from the regular transmission terminal to the irregular transmission terminal by the same method.

  As described above, in the present embodiment, when the difference in the measured value of the sum of the irregular data transmission times in a certain period is equal to or less than the threshold value, the irregular transmission terminal is regarded as a regular transmission terminal. For this reason, the same effect as Embodiment 2 can be obtained, and a stable transmission time can be assigned to the irregular transmission terminal. In addition, when a terminal that cannot be identified as periodic transmission or irregular transmission is included, it is initially treated as irregular transmission and can be changed to a periodic transmission terminal in the same procedure as in this embodiment. It is also possible to appropriately cope with a system including a terminal that cannot determine periodic transmission.

Embodiment 5 FIG.
FIG. 9 is a diagram showing a network configuration example for explaining the route changing method according to the fifth embodiment of the present invention. The configuration of the terminal according to the present embodiment is the same as the configuration of the terminal according to the second embodiment shown in FIG. Hereinafter, a different part from Embodiment 2 is demonstrated.

  Terminals 42 and 43 shown in FIG. 9 are irregular transmission terminals, and packets are transferred along the route indicated by the arrow. That is, the terminal 41 transfers the data of both the terminal 42 and the terminal 43 to the sink 40. The terminals 41, 44, and 45 may be regular transmission terminals or irregular transmission terminals. Each terminal transmits data to the sink 40. The communicable area 101 is a range in which a signal transmitted from the terminal 41 can be received, the communicable area 102 is a range in which a signal transmitted from the terminal 43 can be received, and the communicable area 103 is a terminal 44. It is assumed that the signal transmitted from can be received. In the network configuration shown in FIG. 9, the operation when changing the transmission path of irregular data when the irregular transmission time sum in the terminal 41 is likely to exceed the irregular transmission available time total will be described.

  FIG. 10 is a chart showing an example of an operation when changing the transmission path of irregular data. FIG. 10 shows an operation when changing the transmission path of irregular data when the total irregular transmission time in terminal 41 is likely to exceed the total irregular transmission time in the network configuration shown in FIG. .

  The transmission time management unit 5 of each terminal measures the irregular data transmission time in a predetermined period (here, less than one hour) for each irregular transmission terminal, and performs irregular transmission per fixed period (here, one hour). The total predicted terminal transmission time for each terminal is calculated. As a calculation method, for example, for each irregular transmission terminal, the transfer time in the own terminal of irregular data transmitted from the irregular transmission terminal in 10 minutes is measured and multiplied by six. Alternatively, the transfer size of the irregular data transmitted from the irregular transmission terminal in 10 minutes is divided by the transmission rate and multiplied by 6. Note that the measurement time (predetermined time) and the measurement method are not limited to this. The terminal that has determined that the sum of the predicted terminal transmission time sums (total predicted terminal transmission time sums) of each irregular transmission terminal exceeds the total irregular transmission possible time total selects the irregular transmission terminal that changes the irregular data transfer path Then, a route change request packet is transmitted.

  The terminal 41 that has determined that the sum of the predicted terminal transmission time sums of the irregular transmission terminals exceeds the irregular transmission available time total selects the irregular transmission terminal that changes the irregular data transfer path. As a method of selecting an irregular terminal whose route is to be changed, the route of the selected irregular terminal such as a method of selecting an irregular terminal having the largest estimated terminal transmission time sum and a method of selecting an irregular terminal having a low received power is selected. Any selection method may be used as long as the sum of the predicted terminal transmission time sums of the irregular transmission terminals becomes equal to or less than the total irregular transmission possible time by changing, and there is no particular limitation. Here, it is assumed that the terminal 43, which is an irregular terminal, is selected as a terminal that changes the transfer path of irregular data. The terminal 41 transmits the route change request packet to the terminal (here, the terminal 43) that transmits the irregular data directly to the terminal (step S41). In the route change request packet, the transmission terminal (route change request terminal) address (here, the address of the terminal 41) and the selected irregular data are directly transferred to the route change request packet sending terminal (here, the terminal 41). Terminal address (here, the address of the terminal 43), the selected irregular data transmission terminal address (here, the address of the terminal 43), and the total irregular data prediction terminal transmission time. Note that the route change request packet transmitted to the terminal 43 also overhears the sinks 40, 42, 44, 45 existing in the communicable area 101. In addition, when the route change of one terminal does not satisfy the above condition, it is possible to select a plurality of terminals and perform a plurality of route changes. For example, a route change request packet is transmitted for each route to be changed.

  The terminal 43 that has received the route change request packet transmits to the terminal 41 a route change response packet including its own terminal address (here, the address of the terminal 43) and the address of the route change request terminal (here, the terminal 41). (Step S42). Note that the route change response packet transmitted to the terminal 41 also overhears the terminals 42, 44 and 45 in the communicable area 102.

  Here, of the terminals 42, 44, 45 that have received both the route change request packet and the route change response packet, the terminals 44, 45 that have not transmitted irregular data to the terminal 41 that is the source of the route change request packet. Becomes a route change destination candidate. The transmission time management unit 5 of the terminals 44 and 45 recognizes that its own terminal has become a route change destination candidate based on the route information and the received route change request packet and route change response packet.

  The transmission time management unit 5 of the terminals 44 and 45 that are the route change destination candidates includes the sum of the predicted terminal transmission time sums of the irregular transmission terminals obtained by the own device and the irregular data prediction terminal included in the route change request packet. When the sum of the transmission time sums is equal to or less than the sum of the irregular transmission possible times, a route change confirmation packet is transmitted after the random backoff time. Here, in the terminal 44, the sum of the measured predicted terminal transmission time sum of each irregular transmission terminal and the total irregular data prediction terminal transmission time sum included in the path change request packet is equal to or less than the total irregular transmission possible time. As a result, the terminal 44 transmits a route change confirmation packet to the source of the route change response packet (here, the terminal 43) (step S43). The route change confirmation packet includes its own terminal address (here, the address of the terminal 44) and the source address of the route change response packet (here, the address of the terminal 43). The terminal 41 that has overheard the route change confirmation packet recognizes that the route change has been completed. Further, the route management unit 4 of the terminal 43 that has received the route change confirmation packet changes the irregular data transfer destination of the terminal 43 from the terminal 41 to the terminal 44.

  Note that if the route change confirmation packet is not received within a certain period of time after the route change response packet is received, the terminal 41 determines that there is no route change destination for the irregular data transferred from the terminal 43, and other irregular A transmission terminal is selected and a route change request packet is transmitted to the selected terminal.

  Further, although not shown in FIG. 9, a route in a loop state is constructed by excluding a terminal that has already transferred irregular data specified by a route change request packet from terminals that are route change destination candidates. Can be prevented.

  Further, in this embodiment, the route is changed for each irregular data transmission terminal, but the predicted terminal transmission time total for each terminal from which the terminal itself directly receives irregular data, including the transmission of irregular data, is obtained. It is also possible to change the route of all irregular data transmitted from the corresponding terminal. The operations of the present embodiment other than those described above are the same as those of the second embodiment.

  As described above, in the present embodiment, when the total predicted terminal transmission time sum of each irregular transmission terminal exceeds the irregular transmission possible time total, the irregular data transfer path is changed. For this reason, the same effect as in the second embodiment can be obtained, and the transmission prohibition state of irregular data can be avoided.

Embodiment 6 FIG.
FIG. 11 is a diagram showing a network configuration example for explaining the data transmission method according to the sixth embodiment of the present invention. The configuration of the terminal according to the present embodiment is the same as the configuration of the terminal according to the second embodiment shown in FIG. Hereinafter, a different part from Embodiment 2 is demonstrated. A communicable area 104 indicates a range in which a signal transmitted from the terminal 51 can be received.

  In the second embodiment, the total transmittable time in each terminal is divided into the total periodical transmittable time and the total periodical transmittable time so that the periodic transmission terminal can be protected even when the transmission amount of the irregular transmission terminal is large. However, in this embodiment, when the irregular transmission time total exceeds the irregular transmission available time total, transmission is performed by switching the transmission mode.

  Terminals 52 and 53 shown in FIG. 11 are irregular transmission terminals, and packets are transferred along the route indicated by the arrow. The terminal 51 transfers both the irregular data from the terminal 52 and the irregular data from the terminal 53 to the terminal 50.

  In the state of FIG. 11, when the total irregular transmission time of the terminal 51 is likely to exceed the total irregular transmission possible time, the transmission mode is switched. FIG. 12 is a chart showing an example of the transmission mode switching operation. Note that CS in FIG. 12 indicates carrier sense. Similarly to the fifth embodiment, the transmission time management unit 5 of each terminal obtains the total predicted terminal transmission time sum for each irregular transmission terminal, and the total predicted terminal transmission time sum of each irregular transmission terminal is irregular. It monitors whether or not the total transmission time is exceeded.

  When the sum of the predicted terminal transmission time sums of the irregular transmission terminals does not exceed the irregular transmission available time total in each terminal, the terminal 52 transmits and forwards irregular data as in the second embodiment. Such a normal transmission mode is referred to as a first transmission mode in the present embodiment. In the example of FIG. 12, the terminal 51 transmits irregular data (step S51), and the terminal 52 transfers the received irregular data to the sink 20 (step S52).

  Here, when the sum of the predicted terminal transmission time sums for each irregular transmission terminal exceeds the irregular transmission possible time total in the terminal 51, the terminal 51 enters the buffering mode in which the received data is buffered and transmitted. Transition. After the transition to the buffering mode, when the irregular data is transmitted from the terminal 51 (steps S53 and S55), the terminal 51 stores the received irregular data in its own buffer (not shown in the configuration example of FIG. 4). ). Similarly, when irregular data is transmitted from the terminal 53 (step S54), the terminal 51 stores the received irregular data in the buffer of its own terminal.

  The terminal 51 stores the received irregular data in the buffer until the buffer storage amount exceeds the threshold value. If the buffer storage amount exceeds the threshold value, the terminal 51 transmits a transmission stop request packet for stopping the transmission of the peripheral terminals (step S56). ). The transmission stop request packet includes a transmission prohibition time during which the peripheral terminal prohibits transmission. For example, when using the 950 MHz band, in the communication mode in which the antenna power exceeds 1 mW and 10 mW or less and the carrier sense time is 10 ms or more, there is no provision for the total transmission time per hour. Since a transmission time is given (when the carrier sense time is 128 μs, the transmission time after the carrier sense is 100 ms), the transmission prohibition time included in the transmission stop request is set to 10 ms or more.

  After transmitting the transmission stop request packet, the terminal 51 sets the transmission mode to the second transmission mode in which the total transmission time per hour is not specified (whether the total sum of predicted terminal transmission times exceeds the total amount of irregular transmission possible times) (Transmission mode without monitoring), carrier sense is performed, and irregular data stored in the buffer is aggregated and transmitted (aggregate data transfer) to the terminal 50 (step S57). Thereafter, the first transmission mode may be entered, or the buffering mode may be entered.

  In this embodiment, all irregular data is buffered in the buffering mode. However, priority is given to the irregular transmission packet, and the irregular transmission packet stored in the buffer based on the priority is not accumulated. It is also possible to divide into irregular transmission packets.

  The buffer storage amount may be an amount that can be transmitted in one transmission time in the second transmission mode (communication mode in which the total transmission time per hour is not specified).

  As described above, in the present embodiment, a terminal whose total sum of predicted terminal transmission times for each irregular transmission terminal exceeds the total irregular transmission time is stopped by the transmission stop request packet, and the long-term transmission is stopped. Carrier sense time and transmission time were secured. As a result, the same effect as in the second embodiment can be obtained, and the transmission prohibition state of irregular data can be avoided.

  As described above, the wireless communication device, the wireless communication system, and the route construction method according to the present invention are useful for a system in which a transmission time per hour is limited.

DESCRIPTION OF SYMBOLS 1 Control part 2 Radio | wireless part 3 Antenna 4 Path | route management part 5 Transmission time management part 6 Path | route storage part 7 Actual transmission time memory | storage part 8 Reserved transmission time memory | storage part 9 Regular transmission time memory | storage part 10 Irregular transmission time memory | storage part 21-26, 31-34, 41-45, 50-53 Terminal 20, 30, 40 Sink 101-104

Claims (18)

A wireless communication device that constitutes a communication system in which a total transmittable time that is a sum of transmission times per unit time is defined,
When functioning as a periodic transmission device in which the terminal transmission time sum, which is the sum of the transmission time of the own device per unit time excluding the transfer time of data transmitted from other devices, is known,
A reserved transmission time storage unit for storing a reserved transmission time sum which is a sum of transmission times of the reserved own device including a transfer time of data transmitted from another periodic transmission device;
A route management unit that manages route information and stores and transmits the terminal transmission time total in a route request packet that requests route construction to the destination device when constructing a route from the own device to the destination device;
When a route request packet that does not have its own device as a destination device transmitted from another periodic transmission device is received, the terminal transmission time total stored in the route request packet and the reservation transmission time storage unit store the A transmission time management unit that determines whether or not a total value of the reservation transmission time total exceeds the total transmission time,
With
The route management unit determines whether to forward the received route request packet toward the destination device based on a determination result by the transmission time management unit,
When the transmission time management unit receives a route response packet transmitted from a destination device as a response to the route request packet, the transmission time management unit adds the reserved transmission time total stored in the reserved transmission time storage unit to the route request packet. Add the stored terminal transmission time sum,
A wireless communication apparatus.   The wireless communication apparatus according to claim 1, wherein an initial value of the total reservation transmission time is set as a terminal transmission time total of the own apparatus. Non-scheduled transmission time storage for storing the sum of non-scheduled transmission times, which is the sum of the transmission times of the own device including the transfer time of data transmitted from the non-scheduled transmitting device which is a wireless communication device whose terminal sum is not known Part,
Further comprising
The transmission time management unit may allocate the total said transmittable time to the sum irregular transmittable time assigned to transmit from the irregular transmission device and periodically transmittable time sum to allocate the transmission from the periodic transmission apparatus, wherein a reservation transmission time sum to the sum the periodic transmission possible time,
When the route management unit receives a route request packet transmitted from another irregular transmission device that does not designate the own device as a destination device, the route management unit transfers the route request packet and transmits it from the destination device as a response to the route request packet. Forwarded route response packet,
The transmission time management unit, when transferring data transmitted from an irregular transmission device, adds the time required for transmission of the data to the irregular transmission time sum stored in the irregular transmission time storage unit. The wireless communication apparatus according to claim 1, wherein addition is performed. The wireless communication apparatus according to claim 3, characterized in that a zero initial value of the sum the irregular transmission time. A wireless communication device that constitutes a communication system in which a total transmittable time that is a sum of transmission times per unit time is defined,
When functioning as an irregular transmission device whose terminal transmission time sum, which is the sum of the transmission times of the own device per unit time excluding the transfer time of data transmitted from other devices, is unknown,
A periodic transmission time storage unit for storing a periodic transmission time sum that is a sum of transmission times of the reserved device including the transfer time of data transmitted from the periodic transmission device;
An irregular transmission time storage unit for storing an irregular transmission time sum that is a sum of transmission times of the reserved own device including a transfer time of data transmitted from another irregular transmission device;
A route management unit for managing route information and transmitting a route request packet for requesting route construction to the destination device when constructing a route from the own device to the destination device;
Said transmittable time sum allocated to the sum irregular transmittable time assigned to transmit from the irregular transmission device and periodically transmittable time sum to allocate the transmission from the periodic transmission device, not the own device and the destination device terminal When a route request packet transmitted from a periodic transmission device whose transmission time sum is known is received, the terminal transmission time sum stored in the route request packet and the periodic transmission stored in the periodic transmission time storage unit A transmission time management unit that determines whether or not a total value with the total time exceeds the total periodical transmission available time;
With
The route management unit determines whether or not to forward the received route request packet to the destination device based on the determination result by the transmission time management unit. When the route request packet transmitted from the periodic transmission device is received, the route request packet is transferred, and the route response packet transmitted from the destination device is transferred as a response to the route request packet.
When the transmission time management unit receives a route response packet transmitted from the destination device as a response to the route request packet transmitted from the periodic transmission device, the periodic transmission time total stored in the periodic transmission time storage unit To the terminal transmission time sum stored in the route request packet, and when transmitting data from its own device and when transferring data transmitted from other irregular transmission devices, the time required for data transmission is The wireless communication device, characterized by being added to the sum of the irregular transmission times stored in the irregular transmission time storage unit. The periodic transmission of the initial value of the time sum to 0, the radio communication apparatus according to claim 5, the initial value of the sum the irregular transmission time, characterized in that a 0.   The identification information indicating whether the own device is a periodic transmission device or an irregular transmission device is stored in the route request packet and the data to be transmitted, according to any one of claims 3 to 6. Wireless communication device. Of the wireless communication devices in the communication system, the wireless device that is the destination of transmission data as a sink,
When the own device is an irregular transmission device, the data transmitted from the own device and the data received from the irregular transmission device and transferred by the own device are defined as irregular data.
When the wireless communication device transmits data directly to the sink or the sink,
The transmission time management unit measures the transmission time of irregular data in the unit time for each irregular transmission device, and when the total transmission time of each irregular transmission device exceeds a predetermined threshold, A rate change request packet for requesting an increase in the total amount of non-periodic transmittable time added with an increase time that is an increase time of the total transmittable time is transmitted to the non-periodic transmission device that constructs a route to the sink as a destination; when receiving the ratio change confirmation packet is a response to the rate change request packet, adding the increased time from the sum periodically transmittable time Rutotomoni irregular transmittable time sum to subtracting the increased time,
When a rate change confirmation packet is received from another wireless communication device,
The transmission time management unit updates the total periodical transmittable time and the total periodical transmittable time based on a ratio change request packet corresponding to the ratio change confirmation packet. The wireless communication apparatus according to one. When a rate change request packet destined for its own device is received,
The transmission time management unit, when the total periodical transmittable time after subtracting the increase time included in the received ratio change request packet is equal to or greater than the total periodical transmission time, a ratio change confirmation packet for the ratio change request packet The wireless communication apparatus according to claim 8, wherein the periodic transmission possible time total and the irregular transmission possible time total are updated based on the ratio change request packet. When the wireless communication device transmits data directly to the sink or the sink,
When the total transmission time of each measured irregular transmission device falls below a predetermined lower threshold, the transmission time management unit adds the periodic transmission possible time total to which the periodic increase time that is an increase time of the periodic transmission possible time total is added. When a rate change request packet for requesting an increase is transmitted and a rate change confirmation packet that is a response to the rate change request packet is received, the periodic increase time is added to the sum of the periodically transmittable times and the irregularly transmittable time The wireless communication apparatus according to claim 8 or 9, wherein the periodic increase time is subtracted from a sum. Of the wireless communication devices in the communication system, the wireless device that is the destination of transmission data as a sink,
When the own device is an irregular transmission device, the data transmitted from the own device and the data received from the irregular transmission device and transferred by the own device are defined as irregular data.
When the wireless communication device transmits data directly to the sink or the sink,
The transmission time management unit measures the transmission time of irregular data in a certain period for each irregular transmission device a plurality of times, and measures the measurement for irregular transmission devices in which a difference between measurement values of a plurality of times is within a predetermined value. Send a type change packet that includes the average transmission time that is the average value,
When receiving the type change packet,
The transmission time management unit adds the average transmission time stored in the type change packet to the total periodic transmission available time, subtracts the average transmission time from the irregular transmission possible time total, and the destination of the type change packet The wireless communication device according to claim 10, wherein the irregular transmission device is changed to a periodic transmission device. If it is a periodic transmission device, the data transmitted from the own device and the data received from the periodic transmission device and transferred by the own device are defined as the periodic data,
When the wireless communication device transmits data directly to the sink or the sink,
The transmission time management unit measures the transmission time of the regular data in the unit time a plurality of times for each regular transmission device, and the measurement value of the measurement value for a periodic transmission device in which a difference between the measurement values of a plurality of times exceeds a predetermined value. Send a type change packet instructing the change to the irregular transmission device storing the average transmission time that is an average value,
When a type change packet instructing a change to an irregular transmission device is received, the average transmission time stored in the type change packet is added to the total amount of irregular transmission possible time, and the average transmission time can be transmitted periodically 12. The wireless communication apparatus according to claim 11, wherein the wireless communication apparatus subtracts from the total time and changes the periodic transmission apparatus that is the destination of the type change packet to an irregular transmission apparatus. When the own device is an irregular transmission device, the data transmitted from the own device and the data received from the irregular transmission device and transferred by the own device are defined as irregular data.
The transmission time management unit calculates a total predicted terminal transmission time sum that is a sum of predicted values of transmission times of irregular data in the unit time of each irregular transmission device, and the total predicted terminal transmission time total is a predetermined value. When the threshold value is exceeded, the device that changes the route is selected from the irregular transmission devices that construct the route including the own device, and the total prediction terminal is transmitted to the route change request packet that requests the selected device to change the route. When a route change request packet destined for the device itself is received, a route change request packet that is a response to the route change request packet is sent, and the route change request packet and the route change request are sent. When both the route change response packet corresponding to the packet is received, the total predicted terminal transmission time sum stored in the route change request packet If the result of addition to the total predicted terminal transmission time sum obtained by the above is less than or equal to the irregular transmission possible time sum, the data transmission route from the destination of the route change request packet is changed to the transmission source device of the route change request packet. The route change confirmation packet and the route change confirmation packet corresponding to the route change request packet transmitted from the own device are transmitted by changing the route to the route via the own device without passing through and transmitting the route change confirmation packet notifying the change to the route. The wireless communication apparatus according to claim 3, wherein a route change based on the route change confirmation packet is performed when the packet is received. When the own device is an irregular transmission device, the data transmitted from the own device and the data received from the irregular transmission device and transferred by the own device are defined as irregular data.
The transmission time management unit calculates a total predicted terminal transmission time sum that is a sum of predicted values of transmission times of irregular data in the unit time of each irregular transmission device, and the total predicted terminal transmission time total is a predetermined value. When the buffering start threshold is exceeded, the received irregular data is stored in the buffer, and when the buffer storage amount reaches the buffering end threshold, a transmission stop request packet with a transmission prohibition time added is transmitted and the carrier Sense, collect and transmit the data stored in the buffer after carrier sense, and when a transmission stop request packet is received, data from the own device during the transmission prohibition time stored in the transmission stop request packet Transmission is stopped, The radio | wireless communication apparatus as described in any one of Claims 3-10 characterized by the above-mentioned. A wireless communication system in which a total transmittable time that is a sum of transmission times per unit time is defined,
A periodic transmission device having a known terminal transmission time sum that is a sum of transmission times of the device per unit time excluding a transfer time of data transmitted from another device,
The periodic transmission device includes:
A reserved transmission time storage unit for storing a reserved transmission time sum which is a sum of transmission times of the reserved own device including a transfer time of data transmitted from another periodic transmission device;
A route management unit that manages route information and stores and transmits the terminal transmission time total in a route request packet that requests route construction to the destination device when constructing a route from the own device to the destination device;
When a route request packet transmitted from another periodic transmission device that does not have its own device as a destination device is received, the terminal transmission time sum stored in the route request packet and the reserved transmission time storage unit store the A transmission time management unit that determines whether or not a total value of the reservation transmission time total exceeds the total transmission time,
With
The route management unit determines whether to forward the received route request packet toward the destination device based on a determination result by the transmission time management unit,
When the transmission time management unit receives a route response packet transmitted from a destination device as a response to the route request packet, the transmission time management unit adds the reserved transmission time total stored in the reserved transmission time storage unit to the route request packet. Add the stored terminal transmission time sum,
A wireless communication system. A wireless communication system in which a total transmittable time that is a sum of transmission times per unit time is defined,
Periodic transmission apparatus in which terminal transmission time sum, which is the sum of transmission times of the own apparatus per unit time excluding transfer time of data transmitted from other apparatuses, is known, and irregular transmission in which terminal transmission time sum is not known An apparatus,
The regular transmission device and the irregular transmission device are:
A periodic transmission time storage unit for storing a periodic transmission time sum that is a sum of transmission times of the reserved device including the transfer time of data transmitted from the periodic transmission device;
An irregular transmission time storage unit for storing an irregular transmission time sum that is a sum of transmission times of the own device including a transfer time of data transmitted from the irregular transmission device;
A route management unit for managing route information and transmitting a route request packet for requesting route construction to the destination device when constructing a route from the own device to the destination device;
Said transmittable time sum allocated to the sum irregular transmittable time assigned to transmit from the irregular transmission device and periodically transmittable time sum to allocate the transmission from the periodic transmission device, not the own device and the destination device terminal When a route request packet transmitted from a periodic transmitter whose transmission time sum is known is received, the terminal transmission time sum stored in the route request packet and the periodic transmission stored in the reserved transmission time storage unit A transmission time management unit that determines whether or not a total value with the total time exceeds the total periodical transmission available time;
With
The route management unit determines whether or not to forward the received route request packet to the destination device based on a determination result by the transmission time management unit, and the own device transmitted from the irregular transmission device When a route request packet that is not a destination device is received, the route request packet is transferred, and a route response packet transmitted from the destination device is transferred as a response to the route request packet.
When the transmission time management unit receives a route response packet transmitted from a destination device as a response to the route request packet, the transmission time management unit adds the periodic transmission time stored in the periodic transmission time storage unit to the route request packet. When the sum of stored terminal transmission times is added and the data transmitted from the irregular transmission device is transferred, the irregular transmission time stored in the irregular transmission time storage unit is the time required for data transmission. Add to the sum,
The periodic transmission device stores a terminal transmission time sum in a route request packet for requesting route construction to the destination device when constructing a route from the own device to the destination device,
The said irregular transmission apparatus adds the time required for the transmission of data to the said irregular transmission time sum total, when transmitting data from a self-apparatus. A route construction method in a wireless communication system in which a total transmittable time that is a sum of transmission times per unit time is defined,
A periodic transmission device having a known terminal transmission time sum that is a sum of transmission times of the device per unit time excluding a transfer time of data transmitted from another device,
The periodic transmission device includes:
A reserved transmission time storage unit for storing a reserved transmission time sum that is a sum of transmission times of the reserved own device including a transfer time of data transmitted from another periodic transmission device;
With
A path construction request step for storing the terminal transmission time sum in a route request packet for requesting a path construction to the destination apparatus when the periodic transmission apparatus constructs a path from the own apparatus to the destination apparatus; and
The relay device, which is the periodic transmission device that has received a route request packet transmitted from another periodic transmission device that does not have its own device as the destination device, stores the terminal transmission time sum stored in the route request packet and the reserved transmission time storage An excess determination step of determining whether or not a total value of the reserved transmission time total stored in the section exceeds the total transmittable time;
A forwarding determination step for determining whether or not the relay device forwards the received route request packet toward the destination device based on a determination result by the excess determination step;
When the periodic transmission device that has transmitted the route request packet receives a route response packet transmitted from a destination device as a response to the route request packet, the reserved transmission time total stored in the reserved transmission time storage unit A sum addition step of adding the terminal transmission time sum stored in the route request packet to
Path construction method, which comprises a. A route construction method in a wireless communication system in which a total transmittable time that is a sum of transmission times per unit time is defined,
Periodic transmission apparatus in which terminal transmission time sum, which is the sum of transmission times of the own apparatus per unit time excluding transfer time of data transmitted from other apparatuses, is known, and irregular transmission in which terminal transmission time sum is not known An apparatus,
The regular transmission device and the irregular transmission device are:
A periodic transmission time storage unit for storing a periodic transmission time sum that is a sum of transmission times of the reserved device including the transfer time of data transmitted from the periodic transmission device;
An irregular transmission time storage unit for storing an irregular transmission time sum that is a sum of transmission times of the own device including a transfer time of data transmitted from the irregular transmission device;
With
Allocating the total transmittable time to the total periodical transmittable time allocated to transmission from the regular transmission device and the irregular total transmittable time allocated to transmission from the irregular transmission device ,
A first route construction requesting step for transmitting a route request packet for requesting route construction to the destination device when the irregular transmission device constructs a route from the own device to the destination device;
When the periodic transmission device constructs a route from its own device to the destination device, a second route construction request is transmitted by storing the terminal transmission time total in a route request packet for requesting route construction to the destination device. Steps,
When the first relay device that is the periodic transmission device or the irregular transmission device that has received the route request packet that does not use the own device as the destination device transmitted from the periodic transmission device, receives the route request packet, Excess judgment step for judging whether or not the sum of the terminal transmission time total stored in the route request packet and the regular transmission time total stored in the reserved transmission time storage unit exceeds the regular transmission possible time total When,
A transfer determination step in which the first relay device determines whether to transfer the received route request packet to the destination device based on a determination result in the excess determination step;
The second relay device that is the periodic transmission device or the irregular transmission device that has received the route request packet that does not have the own device as the destination device transmitted from the irregular transmission device transfers the route request packet, and A packet transfer step for transferring a route response packet transmitted from the destination device as a response to the route request packet;
When the periodic transmission device and the irregular transmission device that transmitted the route request packet receive a route response packet transmitted from a destination device as a response to the route request packet, the periodic transmission device is stored in the periodic transmission time storage unit. A periodic transmission sum addition step of adding the terminal transmission time sum stored in the route request packet to the periodic transmission time sum;
When the periodic transmission device and the irregular transmission device that have received the data transmitted from the irregular transmission device transfer data from the irregular transmission device, the time required for data transmission is the irregular transmission time. An irregular transmission sum adding step for adding to the irregular transmission time sum stored in the storage unit;
When the irregular transmission device transmits data from its own device, the own device addition step of adding the time required for data transmission to the irregular transmission time sum stored in the irregular transmission time storage unit; ,
A path construction method comprising:

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