JP5125972B2 - Wireless terminal device, wireless relay device, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio terminal device capable of operating in a power-saving fashion at a wireless communication system, when the system includes a lot of the radio terminal devices. <P>SOLUTION: The radio terminal device 2 includes a radio receiver 27, a memory 22 for address, and a controller 20. The radio receiver 27 receives a beacon. The beacon includes a group information (extended sequence number and mask bit) indicative of a group to which a radio terminal device for receiving the beacon belongs and a contiguity bit indicative whether the operating status of the radio receiver for every group should be maintained to a reception available status according to the remaining amount of data for every group. The memory 22 stores a node address for identifying the own device. Based on a group identification information contained in the received beacon and the node address, the controller 20 computes an activation timing for activating the radio receiver, and stops operation of the radio receiver until the computed activation timing is arrived. Then, the controller 20 activates the radio receiver with the activation timing to receive the beacon, and establishes the operating status of the radio receiver based on the contiguity bit contained in the received beacon. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a wireless terminal device, a wireless relay device, and a program.

  In recent years, development of a wireless communication system in which a wireless network is constructed between a plurality of electronic devices to perform information communication has been advanced. In particular, the development of the field of small-scale wireless PAN (Personal Area Network) in which a person's surroundings are within the communication range is being promoted and is rapidly spreading. This wireless PAN is, for example, ZigBee (registered trademark) in which the physical layer and the MAC layer are standardized in IEEE 802.15, and Bluetooth (registered trademark) in which the physical layer and the MAC layer are standardized in IEEE 802.15.1. It is realized by using.

  ZigBee is standardized by the ZigBee Alliance and uses IEEE802.15.4 for the physical layer and the MAC layer. Therefore, ZigBee is characterized by low cost, low power consumption, and easy installation, while being slower than Bluetooth, and the wireless relay device can be connected to many wireless terminal devices.

  A wireless communication system using ZigBee includes a wireless relay device and a wireless terminal device. A beacon mode is often used as a communication method of this wireless communication system. In the beacon mode, the wireless relay device periodically transmits a beacon signal at a predetermined cycle, all wireless terminal devices receive the beacon, and the wireless terminal device is the wireless relay device in synchronization with the received beacon. Wireless communication.

  When transmitting data from the wireless relay device to the wireless terminal device, the wireless relay device stores and transmits the address of the wireless terminal device that transmits data in the pending address in the beacon. The wireless terminal device that has received the beacon transmits a data request to the wireless relay device and receives data when the beacon has its own address.

In the wireless communication system as described above, the maximum number of wireless terminal device addresses that can be stored in the pending address is up to 7 and is defined by IEEE 802.15.4.
Therefore, for example, in a wireless communication system including one wireless relay device and a large number of eight or more wireless terminal devices, even when data is transmitted to all wireless terminal devices, Only a maximum of 7 addresses can be stored in a single address. Therefore, although only a maximum of seven wireless terminal devices can receive data in one beacon transmission, all wireless terminal devices perform a receiving operation for each beacon transmission time. For this reason, since the wireless terminal device receives a beacon even when it is not necessary to receive data, there is a problem that power is wasted.

Therefore, in a wireless communication system, as a technique for reducing power consumption of a wireless terminal device, when an access point (wireless relay device) transmits data to the wireless terminal device, data indicating the next data transmission time is sent together with the data. It is disclosed that a wireless terminal device is prevented from receiving data other than that addressed to the own station (see Patent Document 1).
JP 2002-300195 A

  However, when the invention described in Patent Document 1 is applied to a wireless communication system having a beacon mode, the wireless terminal device must continue to maintain a beacon receivable state until a beacon addressed to itself can be received. Therefore, in the case of a wireless communication system in which a large number of wireless terminal devices exist, such as an electronic shelf label, there is a problem that a large number of wireless terminal devices that have to maintain a wasteful reception operation for a long time occur.

  In view of the above problems, an object of the present invention is to save power in a wireless terminal device.

In order to solve the above problems, the invention according to claim 1 is a wireless terminal device including a receiving unit that receives a beacon, wherein the beacon indicates a group to which a wireless terminal device that is a reception target of the beacon belongs. A terminal for identifying itself, including identification information and reception state instruction information indicating whether or not the operation state of the reception unit is maintained in a receivable state for each group according to the remaining amount of data for each group Based on the identification information storage unit in which the identification information is stored, the group identification information included in the beacon received by the reception unit, and the terminal identification information, the timing for starting the reception unit is calculated, The operation of the receiving unit is stopped until the calculated timing, and the receiving unit is activated at the calculated timing to receive the beacon. Further comprising a control unit for setting the operating state of the receiver unit based on the reception status indication information included in the received beacon timing is a radio terminal apparatus according to claim.
Furthermore, a program is provided for causing a computer to function as each unit shown in the first aspect of the present invention (the sixth aspect of the present invention).

  According to a second aspect of the present invention, in the wireless terminal device according to the first aspect, when the control unit indicates that the reception state instruction information maintains an operation state of the reception unit in a receivable state, When the receiving unit maintains the operation state of the receiving unit in a receivable state and the beacon received by the receiving unit maintained in the receivable state includes its own terminal identification information, data is received by the receiving unit. It is characterized by receiving.

  According to a third aspect of the present invention, in the wireless terminal device according to the second aspect, when the receiving unit maintained in the receivable state receives the beacon, the group identifying information and the terminal It is determined whether the beacon received by the receiver based on the identification information is a beacon addressed to the group to which the self belongs, and if the beacon is not a beacon addressed to the group to which the self belongs, After reception of data by a wireless terminal device belonging to a certain group is completed, if the beacon includes its own terminal identification information, the reception unit receives the data.

According to a fourth aspect of the present invention, there is provided a transmitting unit that periodically transmits a beacon to a wireless terminal device, group identification information indicating a group to which the wireless terminal device that is a reception target of the beacon belongs, and data remaining for each group. The beacon including the reception state instruction information indicating whether or not to maintain the operation state of the reception unit included in the wireless terminal device for each group according to the amount in a receivable state, and the generated beacon And a control unit that causes the transmission unit to transmit to the wireless terminal device.
Furthermore, a program is provided for causing a computer to function as each section shown in the invention described in claim 4 (the invention described in claim 7).

  According to a fifth aspect of the present invention, in the wireless relay device according to the fourth aspect, the beacon includes terminal identification information of the wireless terminal device that is a transmission target of data, and the control unit includes the beacon to be transmitted. When the data amount of the group to which the wireless terminal device indicated by the terminal identification information to be included exceeds the data amount that can be transmitted within the beacon transmission period, the operation of the receiving unit of the wireless terminal device belonging to the group as the reception state instruction information It is characterized in that the state is maintained in a receivable state.

  According to the present invention, it is possible to save power in the wireless terminal device.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to this embodiment. The embodiment of the present invention shows the most preferable mode of the present invention, and the terminology of the present invention is not limited to this.

First, the configuration will be described.
FIG. 1 shows a schematic configuration diagram of a wireless communication system A in the present embodiment.

  As shown in FIG. 1, a wireless communication system A includes a wireless relay device 1 connected to another wireless relay device or an external device via a wired network 3, and a plurality of wireless relay devices 1 connected to the wireless relay device 1 via wireless communication. The wireless terminal device 2 is provided.

FIG. 2 shows a schematic configuration diagram of the wireless relay device 1.
As shown in FIG. 2, the wireless relay device 1 includes a control unit 10, a storage unit 11, a terminal information memory 12, a beacon transmission timer 13, a wireless transmission unit 14, a wireless reception unit 15, a SW (switching unit) 16, a wired connection An I / F (InterFace) unit 17, a buffer 18, an antenna 19 and the like are provided, and each unit is electrically connected.

  The control unit 10 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The control unit 10 reads out various programs stored in the storage unit 11 and the terminal information memory 12 and programs, tables and data specified from various tables and data, etc., in the RAM or in the storage unit 11 and terminal information. The data is expanded in the work area in the memory 12 and various processes are executed in cooperation with the program. The processing results are stored in the RAM or in a predetermined area of the storage unit 11 or the terminal information memory 12 and wirelessly. An instruction is given to each unit in the relay device 1 to control the overall operation of the wireless relay device 1 in an integrated manner.

  The control unit 10 generates a beacon including terminal identification information (node address), group identification information, and reception state instruction information of a wireless terminal device that is a transmission target of data, and the generated beacon is transmitted to the wireless terminal by the wireless transmission unit 14. A beacon transmission process for periodically transmitting to the device 2 is executed.

  When the control unit 10 includes the reception state instruction information in the beacon, the data amount of the group to which the wireless terminal device indicated by the node address included in the transmitted beacon belongs exceeds the data amount that can be transmitted within the beacon transmission interval. The reception state instruction information indicating that the operation state of the wireless reception unit of the wireless terminal device belonging to the group is maintained in a beacon receivable state.

  A beacon is packet data transmitted from the wireless relay device 1 at regular intervals, and is for synchronizing the wireless terminal device 2 and the wireless relay device 1 connected to the wireless communication system A.

FIG. 3 shows an example of a beacon format in the present embodiment.
As shown in FIG. 3, the beacon has a MAC (Media Access Control) header area B1, a MAC payload area B2, and an MFR (MAC Footer) area B3.

  The MAC payload area B2 includes an SS (Superframe Specification) B21, a GTS (Guaranteed Time Slot) field B22, a PA (Pending Address) field B23, a beacon payload B24, and the like.

  SS is a detailed information field of a superframe, and defines a beacon transmission interval and a beacon communication method for time management when a beacon is received. The GTS field includes information on a communication method (for example, GTS) guaranteed by a specific wireless terminal device. When there is data to be transmitted to the wireless terminal device, the PA field includes identification information (node address) for identifying the wireless terminal device that transmits the data. The beacon payload B24 includes an extended sequence number B24a, continuous bits B24b, and mask bits B24c.

The extension sequence number B24a increases in value every time a beacon is transmitted.
The mask bit B24c defines a value to be extracted from the extended sequence number based on the total number of groups that divide a plurality of wireless terminal devices. The extended sequence number and the mask bit function as group identification information indicating a group to which a wireless terminal device that is a beacon reception target belongs.

  The continuous bit B24b functions as reception state instruction information indicating whether or not the operation state of the wireless reception unit of the wireless terminal device for each group is maintained in a receivable state according to the data remaining amount for each group.

FIG. 4 shows an example of the format of the continuous bit field.
As shown in FIG. 4, when consecutive bits are 2 bytes (16 bits), each bit is created for transmission at present from the least significant bit (LSB) to the most significant bit (MSB). A group of wireless terminal devices to be transmitted by beacons, a group of wireless terminal devices to be transmitted by beacons that are created and transmitted one time before the current time, and are created and transmitted 15 times before the current time. The operation state of the wireless reception unit of the group of wireless terminal devices to be transmitted by the beacon is shown.

  A bit in which “1” is set among the bits constituting this continuous bit indicates an instruction to maintain the operation state of the wireless reception unit of the wireless terminal device belonging to the group corresponding to the bit in a beacon receivable state. Show.

  The storage unit 11 includes a nonvolatile memory that can be electrically erased and rewritten, such as a magnetic or optical recording medium or a semiconductor. The storage unit 11 is fixedly attached to the wireless relay device 1 or is detachable. It is to be attached. For example, FeRAM (Ferroelectric Random Access Memory), MRAM (Magneto resistive Random Access Memory), OUM (phase change recording memory by chalcogenide alloy), etc. can be mentioned. The storage unit 11 stores in advance various programs executed by the control unit 10 and various tables and data used by these programs.

  The terminal information memory 12 is composed of a memory that can be electrically erased and rewritten. The terminal information memory 12 stores information such as the node address of the wireless terminal device 2 existing in the communicable area of the wireless relay device 1 itself.

  The beacon transmission timer 13 is a timer that times the beacon transmission interval, and outputs a beacon transmission timing signal indicating that the time has reached the transmission interval to the control unit 10.

  The wireless transmission unit 14 includes a modulation circuit, an RF (Radio Frequency) circuit, and the like, adjusts the transmission power of the packet, encodes the data to be transmitted in accordance with an instruction from the control unit 10, and transmits the packet. The packet is modulated, and the packet is transmitted to the wireless terminal device 2 via the antenna 19.

  The wireless receiving unit 15 includes a demodulation circuit, an RF circuit, and the like, and is obtained by adjusting the reception sensitivity of the packet, demodulating the packet received via the antenna 19, and analyzing the demodulated packet. The data is output to the control unit 10.

  The SW 16 is provided between the antenna 19 and the wireless transmission unit 14 or the wireless reception unit 15, and transmits a packet from the wireless transmission unit 14 or receives a packet from the antenna 19 in accordance with an instruction from the control unit 10. Switch.

  The wired I / F 17 performs communication control for communicating with another wireless relay device 1 or an external device connected via the wired network 3 by a predetermined communication method.

  The buffer 18 temporarily stores data received via the wired I / F 17.

  The antenna 19 transmits a packet according to the set transmission power or receives a packet according to the set reception sensitivity.

FIG. 5 shows a schematic configuration diagram of the wireless terminal device 2.
As shown in FIG. 5, the wireless terminal device 2 includes a control unit 20, a storage unit 21, an address memory 22, an activation timer 23, a power supply control unit 24, a display control unit 25 a, a display unit 25 b, a wireless transmission unit 26, A wireless receiving unit 27, a SW (switching unit) 28, an antenna 29, and the like are provided, and each unit is electrically connected. The wireless terminal device 2 includes a battery B, and power is supplied from the battery B to each unit in response to a control signal from the power supply control unit 24.

  The control unit 20 includes a CPU, a ROM, a RAM, and the like, reads out various programs stored in the storage unit 21, various programs and tables and data specified from various tables and data, and stores them in the RAM or the storage unit 21. In the work area, execute various processes in cooperation with the above program, store the processing results in a predetermined area of the RAM or storage unit 21, and instruct each unit in the wireless terminal device 2, The overall operation of the wireless terminal device 2 is comprehensively controlled.

  Based on the group identification information (extended sequence number and mask bit) included in the beacon received by the radio reception unit 27 and the node address held in the address memory 22, the control unit 20 The timing for starting the receiving unit (starting timing) is calculated, the operation of the wireless receiving unit 27 is stopped until the calculated starting timing, the beacon is received by starting the wireless receiving unit 27 at the starting timing, and received at the starting timing Based on the reception state instruction information (continuous bits) included in the beacon, a beacon reception process for setting the operation state of the wireless reception unit 27 is executed.

  Further, when the consecutive bits indicate that the operation state of the wireless reception unit 27 is maintained in the receivable state, the control unit 20 maintains the operation state of the wireless reception unit 27 in the receivable state, and enters the receivable state. When the beacon received by the maintained wireless receiving unit 27 includes its own node address, the wireless receiving unit performs control to receive data.

  When the control unit 20 receives data when the wireless reception unit 27 is in a receivable state by the continuous bits of the received beacon, the beacon received by the wireless reception unit 27 based on the group identification information and the continuous bits is received. It is determined whether or not the beacon is addressed to the group to which the user belongs, and if the beacon is not addressed to the group to which the user belongs, reception of data by the wireless terminal device of the group to which the beacon is received is completed. After that, if the beacon includes its own node address, the wireless receiving unit performs control to receive data.

  As the calculation of the activation timing, the control unit 20 includes a first calculated value indicating a value extracted from the extended sequence number using a mass bit, and a second calculated value indicating a value extracted from its own node address using a mask bit; A third calculated value indicating a value obtained by multiplying a preset beacon transmission interval (beacon interval) by the difference value is calculated, and a third calculation is performed at the time (T) when the beacon is received. The time when the values are added is calculated as the activation timing.

FIG. 6 shows examples of extended sequence numbers, mask bits, and node addresses. A calculation example of the first calculated value and the second calculated value will be described with reference to FIG.
As shown in FIG. 6, the extended sequence number, the mask bit, and the node address are each 2 bytes (16 bits) in binary. In FIG. 6, an explanation will be given using an example in which the extended sequence number is represented as “AAAA”, the mask bit is “0003”, and the node address is “FFAA” in hexadecimal. FIG. 6 shows a hexadecimal value corresponding to a binary value shown every 4 bits.

  The first calculated value is a value obtained by ANDing the extended sequence number and the mask bit. In FIG. 6, the shaded bit value “10” of the extended sequence number corresponding to the bit having 1 of the mask bit is calculated as the first calculated value. The second calculated value is a value obtained by ANDing the node address and the mask bit. In FIG. 6, the shaded bit value “10” of the node address corresponding to the bit having 1 of the mask bit is calculated as the second calculation.

  When the lower 2 bits of the mask bit are 1, the first calculated value and the second calculated value extracted from the extended sequence number and the node address are four types of “00”, “01”, “10”, and “11”. It is. Therefore, the control unit 20 identifies a plurality of wireless terminal devices by dividing them into groups for each wireless terminal device having the same lower 2 bits of the node address based on the mask bit and the node address. When the lower 2 bits of the mask bit are 1, the plurality of wireless terminal devices are divided into four groups.

  The value of the mask bit (the number of bits that become 1 of the mask bit) is changed according to the number of wireless terminal devices that can be connected to the wireless relay device 1 that transmits a beacon. In IEEE 802.15.4, it is defined that a maximum of seven node addresses are stored in one beacon. Therefore, the value of the mask bit is determined according to the total number of wireless terminal devices and a multiple of seven.

  When the calculated first calculated value matches the second calculated value, the control unit 20 determines that the received beacon is a beacon addressed to the group to which the self belongs.

  The storage unit 21 is composed of a non-volatile memory that can be electrically erased and rewritten, such as a magnetic or optical recording medium or a semiconductor, and is provided in the wireless terminal device 2 or is detachable. It is to be attached. For example, FeRAM (Ferroelectric Random Access Memory), MRAM (Magneto resistive Random Access Memory), OUM (phase change recording memory by chalcogenide alloy), etc. can be mentioned. The storage unit 21 stores in advance various programs executed by the control unit 20 and various tables and data used in these programs.

  The address memory 22 is composed of a nonvolatile memory that can be electrically erased and rewritten. The address memory 22 stores terminal identification information (node address) for identifying the wireless terminal device 2 itself, and the address memory 22 functions as an identification information storage unit.

  The activation timer 23 is a timer that times the activation timing (activation time) of the wireless reception unit 27 calculated by the control unit 20, and outputs an activation timing signal indicating that the activation timing has been reached to the control unit 20.

  The power control unit 24 controls the power supply of the entire wireless terminal device 2 in accordance with an instruction from the control unit 20, and supplies power from the battery B to each unit in the wireless terminal device 2.

  The battery B is, for example, a primary battery such as an alkaline battery or a manganese battery, or a secondary battery such as a nickel cadmium battery, a nickel hydrogen battery, or a lithium ion battery.

  The display control unit 25a displays various information on the display unit 25b in accordance with the display instruction input from the control unit 20.

  The display unit 25b is configured by an LCD (Liquid Crystal Display), an EL (Electro Luminescence) display, or the like, and displays various screens on the display according to a signal input from the display control unit 25a.

  The wireless transmission unit 26 includes a modulation circuit, an RF (Radio Frequency) circuit, and the like, adjusts the transmission power of the packet, encodes data to be transmitted in accordance with an instruction from the control unit 20, and transmits the packet. The packet is modulated, and the packet is transmitted to the wireless relay device 1 via the antenna 29.

  The wireless reception unit 27 includes a demodulation circuit, an RF circuit, and the like, and is obtained by adjusting the reception sensitivity of the packet, demodulating the packet received via the antenna 29, and analyzing the demodulated packet. The data is output to the control unit 20.

  The SW 28 is provided between the antenna 29 and the wireless transmission unit 26 or the wireless reception unit 27, and transmits a packet from the wireless transmission unit 26 or receives a packet from the antenna 29 in accordance with an instruction from the control unit 20. Switch.

  The antenna 29 transmits a packet according to the set transmission power or receives a packet according to the set reception sensitivity.

Next, the operation of the present embodiment will be described with reference to FIGS.
FIG. 7 shows a flowchart of a beacon transmission process executed in the wireless relay device 1. Note that the processing shown in FIG. 7 is executed by the cooperation of the control unit 10 and each unit in the wireless relay device 1 and is executed while power is being supplied to the wireless relay device 1. is there.

  In the present embodiment, the total number of groups is determined in advance according to the number of node addresses stored in the terminal information memory 12. It is also assumed that the value of the mask bit is set in advance according to the total number of groups.

The control unit 10 initializes (sets to 0) n (step S1). In step S1, the extended sequence number is also initialized (set to 0).
n is a value (decimal number) obtained by ANDing the extended sequence number and the mask bit. For example, when the lower 2 bits of the mask bit are 1, n = 0 when the lower 2 bits of the extended sequence number is “00”. When the lower 2 bits of the extended sequence number are “01”, n = 1. When the lower 2 bits of the extended sequence number are “10”, n = 2. When the lower 2 bits of the extended sequence number is “11”, n = 3.

  The control unit 10 determines whether or not a packet including a node address has been received from the wireless terminal device 2 via the wireless reception unit 15 (step S2). When the packet including the node address is received (step S2; YES), the control unit 10 stores the node address included in the received packet in the terminal information memory 12 (step S3), and returns to the process of step S2.

  The control unit 10 increments the extended sequence number (step S4), and generates a beacon packet including the mask bit and the extended sequence number (step S5).

  The controller 10 determines whether or not a beacon transmission timing signal is input from the beacon transmission timer 13 (step S6). When the beacon transmission timing signal is not input (step S6; NO), the control unit 10 returns to the process of step S6.

  When the beacon transmission timing signal is input (step S6; YES), the control unit 10 executes a continuous bit control process described later (step S7) and stores the continuous bits (step S8).

  After step S8, the control unit 10 adds continuous bits to the beacon generated in step S5, causes the wireless transmission unit 14 to transmit the beacon via the antenna 19 (step S9), clears the beacon transmission timer, and Timing of the transmission interval is started (step S10).

  The control unit 10 determines whether a data request is received from the wireless terminal device 2 via the wireless reception unit 15 (step S11).

  When the data request is not received (step S11; NO), the control unit 10 determines whether or not a preset time (predetermined time) has elapsed since the time measured by the beacon transmission timer (step S12). When the predetermined time has not elapsed (step S12; NO), the control unit 10 returns to the process of step S11. When the processing time has elapsed (step S12; YES), the control unit 10 proceeds to the process of step S14.

  When the data request is received (step S11; YES), the control unit 10 generates data addressed to the wireless terminal device 2 that has transmitted the data request, and transmits the data (step S13).

  The control unit 10 adds 1 to n (step S14), and determines whether n is larger than the total number of groups (step S15). When n is less than or equal to the total number of groups (step S15; NO), the control unit 10 returns to the process of step S2.

  When n is larger than the total number of groups (step S15; YES), the control unit 10 initializes the group number (sets to 0) (step S16) and returns to the process of step S2.

  8 to 11 show flowcharts of the continuous bit control process. 8 to 11 are executed by the cooperation of the control unit 10 and each unit in the wireless relay device 1.

The process shown in FIGS. 8 to 11 is a process for setting continuous bits for a predetermined group. That is, the processes shown in FIGS. 8 to 11 are executed for each group. This predetermined group is a group of wireless terminal devices having a node address in which the value obtained by ANDing the extended sequence number and the mask bit matches the value obtained by ANDing the node address and the mask bit. .
In the present embodiment, the processing shown in FIGS. 8 to 11 will be described as an example when the lower 2 bits of the mask bits are 1, that is, when four groups are generated.

  In the processing shown in FIG. 8, the value obtained by ANDing the extended sequence number and the mask bit is set to “00”, and the value obtained by ANDing this value with the node address and the mask bit is the same. An example of processing for setting consecutive bits for group 0 of wireless terminal devices having addresses will be described.

  The control unit 10 determines the value of n (step S101). When n is 0 (step S101; n = 0), the control unit 10 determines whether there is a group having a free capacity (step S102). When n is 0, processing for creating and transmitting a beacon addressed to group 0 is performed in the beacon transmission processing.

  In step S102, the group having free capacity is determined by determining whether or not the remaining amount of data addressed to each group is smaller than the amount of data (beacon transmission data amount DS) that can be transmitted to the wireless terminal device during the beacon transmission interval. To do. If the remaining amount of data addressed to any group is smaller than the amount of beacon transmission data, it is determined in step S102 that there is a group with free capacity. When the remaining amount of data addressed to all the groups is equal to or greater than the beacon transmission data amount, it is determined in step S102 that there is no group with free capacity.

  If there is no group with free capacity (step S102; NO), the control unit 10 sets the least significant bit of consecutive bits to 0 (step S103), and ends this process.

  When there is a group having free capacity (step S102; YES), the control unit 10 determines whether or not a value obtained by subtracting the beacon transmission data amount DS from the data remaining amount D0 of the group 0 is larger than 0 (step S104). ). In step S104, whether or not the data to be transmitted to the wireless terminal devices belonging to group 0 included in the beacon addressed to group 0 can be transmitted within the beacon transmission interval (for wireless terminal devices belonging to group 0, Whether or not there is data to be received in a beacon that is not addressed to the group 0).

  When the value obtained by subtracting the beacon transmission data amount DS from the data remaining amount D0 of the group 0 is 0 or less (step S104; NO), the control unit 10 is a wireless terminal device belonging to the group 0 included in the beacon addressed to the group 0. It is determined that the data to be transmitted can be transmitted within the beacon transmission interval (data transmission is not carried over to the next beacon), and the process proceeds to step S103.

  When the value obtained by subtracting the beacon transmission data amount DS from the data remaining amount D0 of n = 0 is larger than 0 (step S104; YES), the control unit 10 is a wireless terminal belonging to the group 0 included in the beacon addressed to the group 0 It is determined that the data to be transmitted to the apparatus cannot be transmitted within the beacon transmission interval (the data transmission is carried forward to the next beacon), the least significant bit of the consecutive bits is set to 1 (step S105), and this process ends. .

  When n is 1 (step S101; n = 1), the control unit 10 determines whether or not the least significant bit of the consecutive bits stored in step S8 of FIG. 7 is 1 (step S106). The case where n is 1 is a case where a process for creating and transmitting a beacon addressed to group 1 is executed in the beacon transmission process, and data that should still be transmitted to group 0 previously transmitted to the beacon. Is stored in the most significant bit from the least significant bit of the consecutive bits.

  When the least significant bit of the consecutive bits is not 1 (step S106; NO), the control unit 10 could not transmit the group 0 beacon transmitted to the group 0 beacon transmitted before the group 1 beacon transmission. It is determined that there is no data, 1 bit higher bit is set to 0 from the lowest bit of the continuous bits (step S107), and this process is terminated.

  When the least significant bit of the continuous bits is 1 (step S106; YES), the control unit 10 cannot transmit to the group 0 beacon in the group 0 beacon transmitted before the group 1 beacon transmission. It is determined that there is data, and it is determined whether or not the remaining data amount D0 of group 0 is greater than 0 (step S108).

  When the data remaining amount D0 of the group 0 is 0 or less (step S108; NO), the control unit 10 determines that there is no untransmitted data of the group 0, and proceeds to the process of step S107.

  When the data remaining amount D0 of group 0 is larger than 0 (step S108; YES), the control unit 10 subtracts the beacon transmission data amount DS from the value obtained by adding the data amount D1 of group 1 to the data remaining amount D0 of group 0. It is determined whether or not the obtained value is greater than 0 (step S109).

  When the value obtained by subtracting the beacon transmission data amount DS from the value obtained by adding the group 1 data amount D1 to the group 0 data remaining amount D0 is 0 or less (step S109; NO), the control unit 10 It is determined that the data addressed to group 1 and all the untransmitted data addressed to group 0 can be transmitted by the beacon, and the process proceeds to step S107.

  When the value obtained by subtracting the beacon transmission data amount DS from the value obtained by adding the group 1 data amount D1 to the group 0 data remaining amount D0 is greater than 0 (step S109; YES), the control unit 10 In the beacon, it is determined that not all untransmitted data addressed to group 0 can be transmitted, 1 bit higher bit is set to 1 from the least significant bit of the continuous bits (step S110), and this process ends.

  When n is 2 (step S101; n = 2), the control unit 10 determines whether or not the 1-bit higher bit is 1 from the least significant bit of the consecutive bits (step S111). The case where n is 2 is a case where a process for creating and transmitting a beacon addressed to group 2 is executed in the beacon transmission process, and is transmitted from the group 1 or the previous time transmitted to the beacon last time. Whether or not there is still data to be transmitted to the group 0 is stored in the most significant 2 bits from the least significant bit.

  When the most significant bit from the least significant bit stored in step S8 in FIG. 7 is not 1 (step S111; NO), the control unit 10 transmits a beacon immediately before the beacon transmission of group 2 It is determined that there is no data that could not be transmitted to the group 0 in the beacon 1, and the bit that is 2 bits higher than the least significant bit of the consecutive bits is set to 0 (step S 112), and this process ends.

  When the most significant bit from the least significant bit of the consecutive bits is 1 (step S111; YES), the control unit 10 can transmit to the beacon of group 1 transmitted beacon immediately before the beacon transmission of group 2 It is determined that there is no data addressed to group 0, and it is determined whether the remaining data amount D0 of group 0 is greater than 0 (step S113).

  If the remaining data amount D0 of group 0 is 0 or less (step S113; NO), the control unit 10 determines that there is no untransmitted data of group 0, and proceeds to the process of step S112.

  If the data remaining amount D0 of the group 0 is larger than 0 (step S113; YES), the control unit 10 calculates the value obtained by adding the data remaining amount D0 of the group 0, the data remaining amount D1 of the group 1, and the data amount of the group 2. It is determined whether or not the value obtained by subtracting the beacon transmission data amount DS is larger than 0 (step S114).

  When the value obtained by subtracting the beacon transmission data amount DS from the value obtained by adding the remaining data amount D0 of group 0, the remaining data amount D1 of group 1 and the data amount D2 of group 2 is 0 or less (step S114; NO) The unit 10 determines that the data addressed to the group 2 and all the untransmitted data addressed to the group 1 and the group 0 can be transmitted using the beacon addressed to the group 2, and proceeds to the process of step S112.

  When the value obtained by subtracting the beacon transmission data amount DS from the value obtained by adding the remaining data amount D0 of group 0, the remaining data amount D1 of group 1 and the data amount D2 of group 2 is greater than 0 (step S114; YES), control is performed. The unit 10 determines that the untransmitted data addressed to the group 0 cannot be transmitted by the beacon addressed to the group 2, sets the 2 bits higher bit from the least significant bit of the consecutive bits to 1 (step S115), and performs this processing. Exit.

  When n is 3 (step S101; n = 3), the control unit 10 determines whether the most significant bit of 2 bits is 1 from the least significant bit stored in step S8 of FIG. (Step S116). The case where n is 3 is a case where a process of creating and transmitting a beacon addressed to group 3 is executed in the beacon transmission process, and is transmitted from the group 2 or the previous time transmitted to the beacon last time. Whether or not there is still data to be transmitted to group 0 transmitted from the previous group 1 or group 0 is stored in the most significant bit from the least significant bit to the most significant bit.

  In the case where the most significant bit from the least significant bit stored in step S8 in FIG. 7 is not 1 (step S116; NO), the control unit 10 performs the beacon transmission immediately before the group 3 beacon transmission. In the beacon 2, it is determined that there is no data that could not be transmitted to the group 0, 3 bits higher bit from the least significant bit of consecutive bits is set to 0 (step S 117), and this process ends.

  When the most significant bit from the least significant bit of the consecutive bits is 1 (step S116; YES), the control unit 10 can transmit to the beacon of group 2 transmitted beacon immediately before the beacon transmission of group 3. It is determined that there is no data addressed to group 0, and it is determined whether the remaining data amount D0 of group 0 is greater than 0 (step S118).

  When the remaining data amount D0 of group 0 is 0 or less (step S118; NO), the control unit 10 determines that there is no untransmitted data of group 0, and proceeds to the process of step S117.

  When the data remaining amount D0 of group 0 is larger than 0 (step S118; YES), the control unit 10 determines the remaining amount of data D0 of group 0, the remaining amount of data D1 of group 1, the remaining amount of data D2 of group 2, and the group 3 It is determined whether the value obtained by subtracting the beacon transmission data amount DS from the value obtained by adding the data amount D3 is greater than 0 (step S119).

  When the value obtained by subtracting the beacon transmission data amount DS from the value obtained by adding the remaining data amount D0 of group 0, remaining data amount D1 of group 1, remaining data amount D2 of group 2, and data amount D3 of group 3 is 0 or less (Step S119; NO), the control unit 10 determines that the data addressed to Group 3 and all the untransmitted data addressed to Groups 1, 2 and 0 can be transmitted using the beacon addressed to Group 3, and the process of Step S117 Proceed to

  When the value obtained by subtracting the beacon transmission data amount DS from the sum of the group 0 data remaining amount D0, the group 1 data remaining amount D1, the group 2 data remaining amount D2, and the group 3 data amount D3 is greater than 0. (Step S119; YES), the control unit 10 determines that all untransmitted data addressed to group 0 cannot be transmitted in the beacon addressed to group 3, and sets the upper 3 bits from the least significant bit of the consecutive bits to 1. (Step S120), and this process is terminated.

  Note that when the number of groups is greater than 4, the control unit 10 performs the same processing as in steps S116 to S120 according to n.

  For example, if there is no data addressed to group 0 that could not be transmitted in the beacon of group n-1 that was beacon transmitted immediately before the beacon transmission of group n, the control unit 10 sets the data remaining amount D0 of group 0 to 0. In the following cases, when the value obtained by subtracting the beacon transmission data amount DS from the value obtained by adding the data amount of the group n to the total amount of data remaining amount of the group 0 data D0 to the group n-1 is 0 or less, Bits higher than n bits and lower bits of bits are set to 0.

  Further, the control unit 10 is a case where there is data addressed to the group 0 that could not be transmitted in the beacon of the group n−1 transmitted before the beacon transmission of the group n, and the remaining data amount of the group 0 The value obtained by subtracting the beacon transmission data amount DS from the value obtained by adding the data amount of the group n to the total amount of the remaining data amount of the group 0 data D0 to the group n-1 is greater than 0. In this case, the most significant bit of the consecutive bits is set to 1 from the least significant bit.

  The control unit 10 similarly performs the process shown in FIG. 8 for all groups, in the present embodiment, the groups 1, 2 and 3. 9 shows a flowchart of continuous bit control processing for group 1, FIG. 10 shows a flowchart of continuous bit control processing for group 2, and FIG. 11 shows a flowchart of continuous bit control processing for group 3.

  In the process of FIG. 8, the process of n = 0 in the group 0 (steps S102 to S105) is performed when n = 1 in the group 1 (steps S122 to S125), and when n = 2 in the group 2 (steps). Steps S142 to S145) are performed in group 3 when n = 3 (steps S162 to S165).

  The process of n = 1 in the group 0 (steps S106 to S110) is performed when n = 2 in the group 1 (steps S126 to S130) and when n = 3 in the group 2 (steps S146 to S150). In group 3, this is performed when n = 0 (steps S166 to S170).

  The processing of n = 2 in group 0 (steps S111 to S115) is performed when n = 3 in group 1 (steps S131 to S135), and when n = 0 in group 2 (steps S151 to S155). In group 3, this is performed when n = 1 (steps S171 to S175).

  The processing of n = 3 in group 0 (steps S116 to S120) is performed when n = 0 in group 1 (steps S136 to S140), and when n = 1 in group 2 (steps S156 to S160). In group 3, this is performed when n = 2 (steps S176 to S180).

  Thus, when the data amount of the group to which the wireless terminal device indicated by the node address included in the transmitted beacon belongs exceeds the data amount that can be transmitted within the beacon transmission period (beacon transmission interval), the wireless relay device 1 As described above, it is possible to perform a setting for maintaining the operation state of the wireless reception unit of the wireless terminal device belonging to the group in a receivable state. Then, a beacon including this continuous bit and the extended sequence number and mask bit can be periodically transmitted to the wireless terminal device 2.

  FIG. 12 shows a flowchart of beacon reception processing executed in the wireless terminal device 2. Note that the processing shown in FIG. 12 is executed by the cooperation of the control unit 20 and each unit in the wireless terminal device 2, and is executed while power is supplied to the wireless terminal device 2. is there.

  The control unit 20 generates a packet including its own node address stored in the address memory 22, and transmits the packet to the wireless relay device 1 via the wireless transmission unit 26 (step S21).

  The control unit 20 searches for a beacon periodically transmitted from the wireless relay device 1 (beacon search) in order to secure a wireless circuit with the wireless relay device 1 (step S22). When the beacon search is completed and a wireless circuit is secured with the wireless relay device 1, the control unit 10 executes an activation timing calculation process described later (step S23).

  When the beacon is received by the wireless receiving unit 27 (step S24), the control unit 10 determines whether the beacon is addressed to the group to which the control unit 10 belongs based on the beacon analysis result by the wireless receiving unit 27 (step S25).

  In step S25, the extended sequence number and the mask bit are extracted from the received beacon. Then, it is determined whether or not the first calculated value calculated by the extended sequence number and the mask bit included in the beacon matches the second calculated value calculated by the own node address and the mask bit. When the first calculated value and the second calculated value match, it is determined that the received beacon is a beacon addressed to the group to which the self belongs.

  When the received beacon is not a beacon addressed to the group to which the beacon belongs (step S25; NO), the control unit 20 returns to the process of step S22.

  When the received beacon is a beacon addressed to the group to which the self belongs (step S25; YES), the control unit 20 determines whether or not the own node address is included in the PA field of the received beacon (step S26). ).

  When the own beacon address is included in the PA field of the received beacon (step S26; YES), the control unit 20 executes a data reception process described later (step S27).

  The control unit 20 refers to the continuous bits of the received beacon and determines whether or not the bit corresponding to the group to which the self belongs is 1 in the continuous bits (step S28).

  In step S28, a difference value between the value obtained by ANDing the extended sequence number and the mask bit and the value obtained by ANDing the own node address and the mask bit is calculated, and the least significant bit of the consecutive bits is calculated. It is determined whether or not the bit obtained by adding the difference value calculated from 1 is 1. For example, when the value obtained by ANDing the extended sequence number and the mask bit matches the value obtained by ANDing the own node address and the mask bit, the least significant bit of the consecutive bits is 1. It is determined whether or not. When the value obtained by ANDing the extended sequence number and the mask bit is “10” and the value obtained by ANDing the node address and the mask bit is “00”, the difference value is 2. It is determined whether or not the most significant bit of 2 bits is 1 from the least significant bit of the consecutive bits.

  When the bit corresponding to the group to which the self belongs is not 1 in the continuous bits (step S28; NO), the control unit 20 executes the activation timing calculation process (step S29) and returns to the process of step S24.

  When the bit corresponding to the group to which the self belongs in the consecutive bits is 1 (step S28; YES), the control unit 20 proceeds to the process of step S31.

  When the own node address is not included in the PA field of the received beacon (step S26; NO), the control unit 20 refers to the continuous bit of the received beacon and corresponds to the group to which the self belongs in the continuous bit. It is determined whether or not bit is 1 (step S30). The determination in step S30 is the same as in step S28.

  When the bit corresponding to the group to which the self belongs is not 1 in consecutive bits (step S30; NO), the control unit 20 proceeds to the process of step S29.

  When the bit corresponding to the group to which the self belongs is 1 in consecutive bits (step S30; YES), the control unit 20 prepares to receive a beacon to be received next (step S31). The preparation for reception in step S31 includes maintaining the wireless reception unit 27 in a receivable state.

  When the control unit 20 receives a beacon by the wireless reception unit 27 after step S31 (step S32), the control unit 20 returns to step S26.

  FIG. 13 shows a flowchart of the start timing calculation process. Note that the process shown in FIG. 13 is executed by the cooperation of the control unit 20 and each unit in the wireless terminal device 2.

  The control part 20 sets the time which received the beacon from the radio relay apparatus 1 to T (step S41), and sets the beacon transmission interval contained in the received beacon to SFI (step S42).

  Further, the control unit 20 sets the extension sequence number included in the beacon payload of the received beacon to SCN (step S43), and sets the mask bit to M (step S44). Furthermore, the control unit 20 sets its own node address to ADDR (step S45).

  The control unit 20 sets the AND value of SCN and M to SCN, and sets the AND value of ADDR and M to ADDR (step S46).

  The control unit 20 determines whether or not ADDR is larger than SCN (step S47). When ADDR is equal to or less than SCN (step S47; NO), the control unit 20 adds ADDR to a value obtained by adding 1 to M and sets a new ADDR (step S48). For example, in step S48, when M is “11” and ADDR is “10”, adding 1 to M results in “100”. Then, “110” obtained by adding ADDR value “10” to “100” is set as a new ADDR.

  When ADDR is larger than SCN (step S47; YES), or after step S48, control unit 20 sets a value obtained by subtracting SCN from ADDR (difference value) in NSFI (step S49). This NSFI is the number of beacon transmission intervals from when a beacon is received until the next beacon is received. For example, when ADDR is “10” and SCN is “00”, NSFI is “10”. In this case, NSFI is “2” in decimal. Therefore, the number of beacon transmission intervals from when a beacon is received until the next beacon is received, that is, NSFI is set to 2.

  The control unit 20 adds T to the value obtained by multiplying NSFI and SFI (third calculated value), subtracts a preset margin time α, and calculates the start timing (start time) (step S50). The control unit 20 sets the calculated activation timing in the activation timer (step S51), starts timing by the activation timer, and minimizes power supply to each unit such as the wireless transmission unit 26 and the wireless reception unit 27. The wireless terminal device 2 is set in a sleep state by stopping the operations of the wireless transmission unit 26 and the wireless reception unit 27 (step S52).

  The control unit 20 determines whether or not an activation timing signal is input from the activation timer 23, and determines whether or not it is an activation time (step S53). If it is not the activation time (step S53; NO), the control unit 20 returns to the process of step S53.

  When it is the activation time (step S53; YES), the control unit 20 clears the activation timer 23, activates each unit that is in the sleep state (step S54), and ends this process.

  FIG. 14 shows a flowchart of the data reception process. Note that the processing shown in FIG. 14 is executed by the cooperation of the control unit 20 and each unit in the wireless terminal device 2.

  The control unit 20 determines whether or not the beacon is addressed to the group to which it belongs, based on the beacon analysis result by the wireless reception unit 27 (step S61). The determination in step S61 is the same as the determination content in step S25, and thus the description thereof is omitted.

  When the received beacon is not a beacon addressed to the group to which it belongs (step S61; NO), the control unit 20 maintains the operation state of the wireless reception unit 27 in a receivable state, and the wireless relay device 1 and other wireless terminal devices 2 is monitored (packet monitor) (step S62).

  The control unit 20 determines whether or not the priority group communication has ended during the packet monitoring (step S63). A priority group is a group that receives data with priority over the group to which it belongs when receiving data transmitted by a beacon.

  For example, a group of wireless terminal devices in which the value obtained by ANDing the extended sequence number of the received beacon and the mask bit matches the value obtained by ANDing the node address and the mask bit is the data This is the group that performs reception with the highest priority (the highest priority group). In other words, the priority of the group receiving data is obtained by subtracting the value obtained by ANDing the node address and mask bit of each wireless terminal device from the value obtained by ANDing the extended sequence number and the mask bit. It corresponds to the value (subtraction value). The smaller the subtraction value, the higher the priority.

  In determining whether the communication of the priority group has ended, the control unit 20 determines whether the group to which each node address included in the PA field belongs is based on the node address included in the PA field of the received beacon. The priority of is calculated. And the control part 20 monitors communication with the radio | wireless terminal apparatus and radio | wireless relay apparatus corresponding to the node address which belongs to the group where priority is higher than the group to which self belongs. When the control unit 20 determines whether or not the communication of the wireless terminal device being monitored has ended, it is determined whether or not the priority group communication has ended.

  If the priority group communication has not ended (step S63; NO), the control unit 20 returns to the process of step S62.

  When the priority group communication is completed (step S63; YES), the control unit 20 determines whether or not there is a margin in the data transfer time (step S64).

  In step S64, for example, the control unit 20 calculates the time until the next beacon is received based on the beacon transmission interval included in the received beacon and the time when the beacon is received, and calculates from the current time. If the time until the time is longer than the time required to receive data from the wireless relay device, it is determined that there is a margin in the data transfer time.

  When there is no allowance for the data transfer time (step S63; NO), the control unit 20 ends this process. When there is a margin in the data transfer time (step S63; YES), the control unit 20 transmits a data request to the wireless relay device 1 (step S65).

  After transmitting the data request to the wireless relay device 1, the control unit 20 receives an ACK (Ackowledgment) from the wireless relay device 1 (step S66) and receives data (step S67).

  When the reception of data is completed, the control unit 20 transmits ACK to the wireless relay device 1 (step S68), and ends this process.

FIG. 15 shows an operation example of a wireless terminal device performing beacon reception processing.
FIG. 15 shows an example in which the mask bit is 3 (the lower 2 bits are 1), and the lower 2 bits of the extended sequence number included in the beacon and the lower 4 bits of consecutive bits are shown.

  The plurality of wireless terminal devices are divided into four groups based on the node address of each wireless terminal device and the mask bits included in the beacon. For example, a plurality of wireless terminal devices are group 0 for wireless terminal devices whose lower 2 bits of the node address are “00”, group 1 for wireless terminal devices whose lower 2 bits of the node address are “01”, and lower 2 bits of the node address. Can be divided into group 2 and wireless terminal devices whose lower 2 bits of the node address are “11” into group 3.

  In the present embodiment, the number of wireless terminal devices belonging to group 0 shown in FIG. 15 is 10, the number of wireless terminal devices belonging to group 1 is 5, and the number of wireless terminal devices belonging to groups 2 and 3 is 0. And The amount of data transmitted to each wireless terminal device is the same, and the amount of data that can be transmitted at the beacon transmission interval is the amount of data transmitted to seven wireless terminal devices.

A wireless terminal device belonging to group 0 receives a beacon addressed to the group to which the wireless terminal device belongs (a beacon having an extended sequence number value of “00” extracted by a mask bit), and receives the own beacon in the PA field of the received beacon. If the node address is included, data reception processing (download) is performed. In the example illustrated in FIG. 15, seven wireless terminal devices receive data from the wireless relay device.
The wireless terminal devices belonging to group 0 maintain the wireless reception unit 27 in a receivable state because the continuous bit (the least significant bit of the continuous bits) of its own group is 1.

Next, the wireless terminal devices belonging to group 0 receive a beacon whose extended sequence number value extracted by the mask bit is “01”, and the node address of the wireless terminal device is included in the PA field of the received beacon. In this case, after the communication of the priority group (group 1) is completed, the data reception process (download) is performed. In the example illustrated in FIG. 15, after the fifth wireless terminal device in group 1 receives data, two wireless terminal devices belonging to group 0 receive data from the wireless relay device.
The wireless terminal device belonging to group 0 maintains the wireless receiving unit 27 in a receivable state because the continuous bit of its own group (bits higher by 1 bit than the least significant bit of the continuous bits) is 1.

When the wireless terminal device belonging to group 0 receives a beacon whose extension sequence number value extracted by the mask bit is “10”, and the received beacon PA field includes its own node address After the communication of the priority groups (groups 1 and 2) is completed, data reception processing (downloading) is performed. In the example shown in FIG. 15, since there are no wireless terminal devices that receive data in groups 1 and 2, one wireless terminal device belonging to group 0 receives data from the wireless relay device after receiving a beacon. .
The wireless terminal devices belonging to group 0 are in the sleep state because the continuous bits of their group (bits higher by 2 bits than the least significant bit of the continuous bits) are 0.

  In addition, the wireless terminal devices belonging to the groups 1, 2, and 3 respectively receive beacons whose extended sequence number values extracted by the mask bits are “01”, “10”, and “11”, respectively. During the transmission interval, it goes to sleep.

  Therefore, it is not necessary for the wireless terminal device 2 to receive all beacons periodically transmitted from the wireless relay device 1, and it is only necessary to receive beacons transmitted at least once every four times.

  Thus, since the wireless terminal device 2 can stop the operation of the wireless reception unit 27 until the activation timing calculated based on the extended sequence number and mask bit included in the beacon and its own node address, the wireless terminal device 2 is transmitted. Therefore, it is possible to reduce the power consumed to receive all beacons. Then, the wireless terminal device 2 receives the wireless signal based on the continuous bits set according to the data remaining amount of the group to which the wireless terminal unit 27 that is activated at the calculated activation timing includes the beacon received. Whether or not the operation state of the unit 27 is maintained in a receivable state can be set. Accordingly, it is possible to continuously receive a beacon while maintaining the operation state of the wireless reception unit 27 included in the wireless terminal device belonging to each group according to the remaining data amount of each group, thereby shortening the data reception completion period. Thus, power saving of the wireless terminal device 2 can be achieved.

  For example, when the number of wireless terminal devices in each group is uneven, in a group composed of a large number of wireless terminal devices, data reception can be performed using beacons addressed to other groups. Since the time utilization of resources (frequency band, power, transmission method, etc.) can be improved, the power consumption can be reduced by the startup initial process at startup.

Furthermore, the wireless terminal device 2 can maintain the wireless reception unit 27 in a receivable state according to the continuous bits, and can receive data when the received beacon includes its own node address.
In particular, when the wireless reception unit 27 maintained in a receivable state receives a beacon, and the beacon is not a beacon addressed to a group to which the beacon belongs, it belongs to a group (priority group) that is a reception target of the beacon. Since the data can be received after the reception of data by the wireless terminal device is completed, the reception of data by the wireless terminal device belonging to the priority group can be prioritized. Accordingly, wireless terminal devices belonging to the priority group can acquire data by receiving a beacon for each group without being affected by the remaining data amount of other groups.

It is a schematic block diagram of a radio | wireless communications system. It is a schematic block diagram of a radio relay apparatus. It is a figure which shows the example of a beacon format. It is a figure which shows the example of a format of a continuous bit field. It is a schematic block diagram of a radio | wireless terminal apparatus. It is a figure which shows the example of an extended sequence number, a mask bit, and a node address. It is a flowchart of a beacon transmission process. 5 is a flowchart of continuous bit control processing for group 0. 5 is a flowchart of continuous bit control processing for group 1; 6 is a flowchart of continuous bit control processing for group 2; 10 is a flowchart of continuous bit control processing for group 3; It is a flowchart of a beacon receiving process. It is a flowchart of a starting timing calculation process. It is a flowchart of a data reception process. It is a figure which shows the operation example of the radio | wireless terminal apparatus which is performing the beacon reception process.

Explanation of symbols

Reference Signs List 1 wireless relay device 2 wireless terminal device 3 wired network 10 control unit 11 storage unit 12 terminal information memory 13 beacon transmission timer 14 wireless transmission unit 15 wireless reception unit 16 SW
17 Wired I / F
18 Buffer 19 Antenna 20 Control Unit 21 Storage Unit 22 Address Memory 23 Start-up Timer 24 Power Supply Control Unit 25a Display Control Unit 25b Display Unit 26 Radio Transmitter 27 Radio Receiver 28 SW
29 Antenna A Wireless communication system B Battery B1 MAC header area B2 MAC payload area B3 MFR area B21 SS
B22 GTS field B23 PA field B24 Beacon payload B24a Extended sequence number B24b Consecutive bits B24c Mask bits

Claims (7)

In a wireless terminal device including a receiving unit that receives a beacon,
The beacon maintains group receiving information indicating a group to which a wireless terminal device that is a reception target of the beacon belongs and an operation state of the receiving unit in a receivable state for each group according to a remaining data amount for each group. Reception status indication information indicating whether or not to perform,
An identification information storage unit in which terminal identification information for identifying itself is stored;
Based on the group identification information and the terminal identification information included in the beacon received by the receiving unit, calculate the timing to start the receiving unit, stop the operation of the receiving unit until the calculated timing, A control unit that activates the reception unit at the calculated timing to receive the beacon, and sets an operation state of the reception unit based on the reception state instruction information included in the beacon received at the calculated timing When,
A wireless terminal device comprising: The controller is
When the reception state instruction information indicates that the operation state of the reception unit is maintained in a receivable state, the operation state of the reception unit is maintained in a receivable state,
If the beacon received by the receiving unit maintained in the receivable state includes its own terminal identification information, receiving data by the receiving unit;
The wireless terminal device according to claim 1. The controller is
When the receiving unit maintained in the receivable state receives the beacon,
Determining whether the beacon received by the receiving unit based on the group identification information and the terminal identification information is a beacon addressed to a group to which the self belongs;
When the beacon is not a beacon addressed to the group to which the beacon belongs, after the reception of data by the wireless terminal device belonging to the group to which the beacon is received is completed, the beacon includes the terminal identification information of the self In this case, receiving data by the receiving unit,
The wireless terminal device according to claim 2. A transmitter that periodically transmits a beacon to a wireless terminal device;
The group identification information indicating the group to which the wireless terminal device that is the reception target of the beacon belongs, and the operation status of the receiving unit included in the wireless terminal device for each group according to the data remaining amount for each group A control unit that generates the beacon including the reception state instruction information indicating whether to maintain the beacon, and causes the transmission unit to transmit the generated beacon to the wireless terminal device;
A wireless relay device comprising: The beacon includes terminal identification information of the wireless terminal device that is a transmission target of data,
The controller is
When the data amount of the group to which the wireless terminal device indicated by the terminal identification information included in the beacon to be transmitted exceeds the data amount that can be transmitted within the beacon transmission period, the wireless terminal device belonging to the group as the reception state instruction information Maintaining the operating state of the receiver in a receivable state;
The wireless relay device according to claim 4. Wireless terminal device computer
Group identification information indicating a group to which a wireless terminal device to be received belongs, and reception indicating whether or not the operation state of the reception unit is maintained in a receivable state for each group according to the remaining data amount for each group Receiving means for receiving a beacon including status indication information;
Based on the group identification information included in the received beacon and terminal identification information for identifying itself, calculate the timing for starting the reception function, stop the operation of the reception function until the calculated timing, Control means for activating the reception function at the calculated timing to receive the beacon, and setting an operation state of the reception function based on reception state instruction information included in the beacon received at the calculated timing;
Program to function as. Wireless relay device computer
A transmission means for periodically transmitting a beacon to a wireless terminal device;
The group identification information indicating the group to which the wireless terminal device that is the reception target of the beacon belongs, and the operation state of the reception unit included in the wireless terminal device for each group according to the data remaining amount for each group. Control means for generating the beacon including reception state instruction information indicating whether to maintain the enabled state, and transmitting the generated beacon to the wireless terminal device by the transmission function;
Program to function as.

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