JP2006287469A - Wireless communication system, wireless communication apparatus, method for processing these system and apparatus, and program for making computer carry out the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control a period in which a transmission station can transmit data preferentially to a reception station considering the situation of a reception buffer of the reception station. <P>SOLUTION: Wireless communication apparatus STA2 transmits a substitute beacon 2002 to wireless communication apparatus STA1 in order to assign a preferential slot for transmitting the data preferentially to the wireless communication apparatus STA1. The wireless communication apparatus STA1 transmits data 1002 by the preferential slot just after the substitute beacon 2002. When detecting absence of vacancy in the reception buffer which is provided at itself, the wireless communication apparatus STA2 transmits a substitute beacon 2004 including information that data transmission has to be stopped to the wireless communication apparatus STA1. When vacancy occurs in the reception buffer, the wireless communication apparatus STA2 transmits a substitute beacon 2005 including information that data transmission is permitted to the wireless communication apparatus STA1. Then, the wireless communication apparatus STA1 starts data transmission. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wireless communication system, and more particularly, to a wireless communication system that assigns a priority slot used for data transmission to a transmission side while taking into account the state of a reception buffer on the reception station side, a wireless communication device used in the system, and The present invention relates to a processing method and a program for causing a computer to execute the method.

  In recent years, the demand for wireless LAN systems has increased remarkably with the increase in speed and cost. In particular, recently, in order to establish a small-scale wireless network between a plurality of electronic devices existing around a person and perform information communication, introduction of a personal area network (PAN) has been studied. For example, different wireless communication systems are defined using frequency bands that do not require a license, such as 2.4 GHz band and 5 GHz band.

  Examples of standard specifications relating to wireless networks include IEEE (Institute of Electrical and Electronics Engineers) 802.11, HiperLAN / 2, IEEE 802.15.3, Bluetooth communication, and the like. In the IEEE802.11 standard, there are extended standards such as IEEE802.11a, b, and g due to differences in wireless communication systems and frequency bands to be used.

  As a method of configuring a local area network using wireless technology, there is a communication method using an “ad hoc mode”. In wireless communication using the ad hoc mode, communication stations directly and asynchronously perform wireless communication. In ad-hoc mode wireless communication, any communication station can directly perform asynchronous wireless communication without using a specific access point. For example, a home network composed of home electric devices is configured. Suitable for According to the ad hoc mode, even if one communication station fails or the power is turned off, the routing is automatically changed, so the network is unlikely to break down. There is a feature that data can be transmitted to a relatively long distance while maintaining a high data rate.

  FIG. 12 is a diagram illustrating a data flow by wireless communication in the wireless communication device STA1 and the wireless communication device STA2 in the conventional ad hoc mode. In FIG. 12, “B” represents a beacon, “AB” represents an auxiliary beacon, and “D” represents data. The wireless communication device STA1 and the wireless communication device STA2 transmit a beacon at a superframe period in order to notify each other of the presence. By this beacon, the wireless communication device STA1 and the wireless communication device STA2 recognize each other. A period during which data can be preferentially transmitted after transmission of the beacon is provided.

  Since the period during which data can be preferentially transmitted with only the beacon can be taken only once in the superframe period, another beacon called an auxiliary beacon is assumed. The auxiliary beacon has a period during which data can be preferentially transmitted like a normal beacon, and is used for the purpose of acquiring the period. This auxiliary beacon is to be transmitted by the wireless communication device STA1 on the data transmitting side by itself.

  When the reception buffer overflows in the wireless communication device STA2, the wireless communication device STA2 transmits a data transmission stop request to the wireless communication device STA1, which is a request to stop data transmission. Upon receiving this data transmission stop request, the wireless communication device STA1 stops data transmission. Thereafter, when the overflow state of its reception buffer is resolved, wireless communication apparatus STA2 transmits a data transmission request to the wireless communication apparatus STA1 to permit data transmission. When the wireless communication apparatus STA1 receives this data transmission request, it starts transmitting data.

  By the way, in the IEEE802.11 standard, when transmitting data, the data transmission side transmits RTS (Request to Send) to the data reception side, and the data reception side responds to CTS (Clear to Send: reception preparation). The transmission of data is started only by transmitting (completion) to the data transmission side. When the data transmission is completed, the receiving side transmits an ACK (Acknowledgment) to the data transmitting side, thereby completing the data transmission. The data transmission request and the data transmission stop request are also transmitted according to this procedure.

In addition, some communication devices mainly receive a lot of information from their own stations, such as servers that store video data and music data, and can receive video data and music data such as displays and headphones. There is a subject. When such a communication device constitutes a wireless network as shown in FIG. 12, the frequency of display and headphones that mainly receive data should be preferentially transmitted. Taking this into consideration, the display or headphone that is the main receiver can transmit the beacon after the beacon is transmitted. A system that lends to a communication device that mainly transmits a large amount of information has been proposed (see, for example, Patent Document 1).
Japanese Patent Laying-Open No. 2005-20163 (FIG. 12)

  In the above-described prior art, data transmission is performed for the convenience of the data transmission station without considering the status of the reception buffer of the reception station, and the reception buffer of the reception station overflows and receives a data transmission stop request. Until then, data transmission continued. For this reason, the data transmitted before the receiving station overflows and the transmitting station receives a data transmission stop request has been lost. Further, since exchange of data transmission request and data transmission stop request is performed according to the IEEE802.11 standard, a certain communication band is occupied.

  Further, in the conventional system, the number of times that a period during which data can be preferentially transmitted at the receiving station can be lent to the transmitting station is small. Since it is the receiving station itself that knows the status of the receiving buffer of the receiving station, it is appropriate that the receiving station controls the period during which data can be transmitted with priority based on the status of the communication band. Depending on the situation of the communication band, it becomes possible to lend a period during which data can be transmitted with higher priority to the transmitting station.

  Therefore, an object of the present invention is to control a period during which a transmitting station can preferentially transmit data at a receiving station in consideration of a receiving buffer state and a communication band state of the receiving station.

  The present invention has been made to solve the above-described problems, and a first aspect thereof is a wireless communication system including a plurality of wireless communication devices, which has been sent from another wireless communication device. A slot number determining means for determining the number of slots required for transmission of transmission data based on data information including a data rate; a communication information holding means for storing communication information including a slot usage status; and based on the communication information. Priority slot acquisition means for acquiring the priority slots for the wireless communication apparatus to preferentially transmit data by the number of slots determined by the slot number determination means, and the priority slots allocated to the other wireless communication apparatuses A first wireless communication apparatus comprising: priority slot allocating means for transmitting a signal including the effect and the timing of the priority slot; Priority slot allocation detecting means for detecting that the priority slot has been allocated, allocation destination determining means for determining whether or not the priority slot has been allocated to the wireless communication apparatus, and data generation for generating the transmission data Means, transmission timing control means for controlling the timing for transmitting the transmission data based on the signal, and detection of assignment of the priority slot and determination that the priority slot is assigned to the wireless communication apparatus And a second wireless communication apparatus comprising transmission means for transmitting the transmission data based on the control of the transmission timing control means. This brings about the effect of using the communication band that is not used based on the information sent from the transmission side and causing the reception side to control the transmission of data on the transmission side.

  The second aspect of the present invention is a slot number determining means for determining the number of slots required for data transmission based on data information including a data rate sent from another wireless communication device, and the use of the slots. Communication information holding means for holding communication information including a situation, and priority slots to which the wireless communication apparatus should preferentially transmit the data based on the communication information are the number of slots determined by the slot number determining means. A wireless communication apparatus comprising: a priority slot acquisition means for acquiring; and priority slot allocation means for allocating the priority slot to the other wireless communication apparatus. This brings about the effect of using the communication band that is not used based on the information sent from the transmission side and causing the reception side to control the transmission of data on the transmission side.

  In the second aspect, the wireless communication device is characterized in that the priority slot acquisition means further notifies the other wireless communication device of information including the timing of the priority slot. Thus, there is an effect that other wireless communication devices that have received information including the priority slot timing are notified of the timing at which the operation should be performed. As a result, power consumption in other wireless communication devices is reduced.

  In the second aspect, the priority slot acquisition unit includes a beacon generation unit that generates a beacon, and acquires a predetermined period after the transmission of the beacon generated by the beacon generation unit as the priority slot. It is characterized by this. This brings about the effect of clarifying the start timing of the priority slot.

  Further, in the wireless communication apparatus, the beacon generating means generates a beacon triggered by a periodic beacon generating means for generating a beacon at a constant cycle and the data information sent from the other wireless communication apparatus. Proxy beacon generating means, and the beacon generated by the beacon generating means is a beacon generated by the proxy beacon generating means. This brings about the effect | action of producing | generating the beacon which can control transmission of the data of a transmission side separately from the beacon which alert | reports an own presence in a wireless network.

  In the wireless communication apparatus, the priority slot assigning means includes a beacon generated by the proxy beacon generating means that the priority slot is assigned to the other wireless communication apparatus. This brings about the effect of recognizing whether the priority slot is assigned to another wireless communication device by analyzing the beacon.

  Further, in the wireless communication device, the priority slot assigning means further includes information specifying the other wireless communication device to which the priority slot is assigned in the beacon generated by the proxy beacon generating means. It is. As a result, it is possible to recognize by analyzing the beacon whether the priority slot is assigned to the wireless communication apparatus that has received the beacon.

  Further, in the wireless communication device, a reception buffer for storing data transmitted from the other wireless communication device, and transmission of data to the other wireless communication device according to the amount of data stored in the reception buffer. It further comprises reception buffer monitoring means for making a request for permission or a request for not permitting transmission. This brings about the effect that the reception side controls the transmission of data on the transmission side according to the situation of the reception buffer on the reception side.

  In the wireless communication apparatus, the reception buffer monitoring means includes a data amount that can be further accumulated in the reception buffer in a request for permitting transmission of the data. As a result, the data transmission side is made to recognize the correct reception buffer status on the reception side.

  In the wireless communication apparatus, the priority slot allocating unit includes a request for permitting transmission of the data or a request for not permitting transmission in the beacon generated by the auxiliary beacon generating unit. Is. Thereby, the communication in communication can be reduced and the effect of using the communication band efficiently is brought about.

  According to a third aspect of the present invention, there is provided receiving means for receiving priority slot data including assigning a priority slot to which the first wireless communication apparatus should preferentially transmit data to the second wireless communication apparatus. , An assignment destination determining means for determining whether or not the wireless communication apparatus corresponds to the second wireless communication apparatus, a data generating means for generating transmission data, and the transmission data based on the timing of the priority slot. A transmission timing control means for controlling a transmission timing; and a transmission means for transmitting the transmission data based on the control of the transmission timing control means when it is determined that the wireless communication apparatus corresponds to the second wireless communication apparatus. A wireless communication device. This brings about the effect that the wireless communication apparatus assigned the priority slot from the receiving side uses the priority slot.

  In the third aspect of the present invention, the priority slot data is included in a beacon transmitted in response to a request from the second wireless communication apparatus. Thereby, the communication in communication can be reduced and the effect of using the communication band efficiently is brought about.

  In the third aspect of the present invention, when the wireless communication device receives a request from the first wireless communication device to permit transmission of data, the wireless communication device transmits the transmission data and allows transmission of data. The apparatus further includes a transmission request determination unit that prevents the transmission data from being transmitted when a request for not being transmitted is received. As a result, the receiving buffer on the receiving side is prevented from overflowing.

  Further, the transmission request determining means transmits a data amount corresponding to the data amount when receiving a data amount receivable in the first wireless communication device from the first wireless communication device. It is. This brings about the effect | action of making the transmission side transmit the data according to the condition of the reception buffer of the reception side.

  Also, in the third aspect of the present invention, the data generation means requests that the assigned priority slot is unnecessary when there is no transmission data to be transmitted. This brings about the effect that the receiving side is informed that it is no longer necessary to transmit data on the transmitting side. That is, it contributes to efficient use of the communication band.

  According to a fourth aspect of the present invention, the first wireless communication apparatus assigns a priority slot to which data should be preferentially transmitted to the second wireless communication apparatus, and data for the first wireless communication apparatus. Receiving means for receiving a beacon including a request to permit transmission or a request not to permit transmission, and an assignment destination determining means for determining whether or not the wireless communication apparatus corresponds to the second wireless communication apparatus; A data generation unit that generates transmission data, a transmission request determination unit that determines whether or not there is a request not to allow transmission of the data to the first wireless communication device, and an allocation destination determination unit When it is determined that the wireless communication device does not correspond to the second wireless communication device, and the transmission request determination means determines that there is a request not to allow transmission of the data, the priority status is determined. Priority slot acquisition means for acquiring the transmission data, transmission timing control means for controlling the transmission timing of the transmission data based on the timing of the priority slot, and transmission data based on the control of the transmission timing control means. A wireless communication apparatus comprising: a transmission unit configured to transmit to the wireless communication apparatus of No. 3; As a result, even if data cannot be transmitted in a situation where there is no space in the reception buffer on the receiving side, the communication band scheduled to transmit the data is effectively used between other wireless communication devices.

  According to a fifth aspect of the present invention, there is provided a processing method in a wireless communication apparatus that retains communication information including a slot usage status, based on data information including a data rate sent from another wireless communication apparatus. The slot number determination procedure for determining the number of slots necessary for data transmission and the priority slot in which the wireless communication apparatus can preferentially transmit the data based on the communication status is determined by the slot number determination procedure. It is characterized by comprising a priority slot acquisition procedure for acquiring only the number of slots, and a priority slot allocation procedure for allocating the priority slot to the other wireless communication device. This brings about the effect of using the communication band that is not used based on the information sent from the transmission side and causing the reception side to control the transmission of data on the transmission side.

  According to a sixth aspect of the present invention, there is provided a receiving procedure for receiving priority slot data including assigning a priority slot to which the first wireless communication apparatus should preferentially transmit data to the second wireless communication apparatus; An assignment destination determination procedure for determining whether or not the wireless communication device corresponds to the second wireless communication device, a data generation procedure for generating transmission data, and the transmission data based on the priority slot timing The transmission timing control procedure for controlling the transmission timing and the transmission timing control means when it is detected that the priority slot is allocated and it is determined that the wireless communication apparatus corresponds to the second wireless communication apparatus. And a transmission procedure for transmitting the transmission data based on the transmission data. This brings about the effect that the wireless communication apparatus assigned the priority slot from the receiving side uses the priority slot.

  Advantageous Effects of Invention According to the present invention, it is possible to achieve an excellent effect that data transfer control can be performed in a receiving station according to the state of the receiving buffer of the receiving station.

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

  FIG. 1 is a diagram showing a configuration of a wireless communication system constructed using a wireless communication apparatus according to an embodiment of the present invention. The wireless communication system according to the embodiment of the present invention assumes a network configuration including an ad hoc mode.

  The embodiment of the present invention also provides a carrier sense multiple access with collision avoidance function (CSMA / CA) when performing media access control in an ad hoc mode wireless communication network. It is assumed that the timing of transmitting data to a network medium (space) is controlled. The CSMA / CA method is a method used to avoid collision of frames (data) as much as possible when performing wireless channel access by autonomous distributed control (DCF).

  In this wireless communication system, various communication methods suitable for relatively short-distance communication applicable to a wireless LAN can be applied as a wireless transmission / reception method. Specifically, a UWB (Ultra Wide Band) system, an OFDM (Orthogonal Frequency Division Multiplexing) system, a CDMA (Code Division Multiple Access) system, or the like can be employed.

  As shown in FIG. 1, the ad hoc mode wireless LAN does not require an access point, and mobile stations (wireless communication apparatuses) STA1, STA2, and STA3 communicate directly with each other. In the ad hoc mode, an IBSS (Independent Basic Service Set) is autonomously defined after negotiation between the wireless communication apparatuses STA1, STA2, and STA3. That is, since the ad hoc mode wireless LAN does not have an access point, the mobile stations (wireless communication apparatuses) STA1, STA2, and STA3 need to notify each other of the existence of each other. In order to notify each other's existence, the mobile stations (wireless communication apparatuses) STA1, STA2, and STA3 periodically transmit beacons. Thereby, IBSS is defined autonomously.

  This beacon includes a parameter called Target Beacon Transmit Time (TBTT) for informing each wireless communication device of a transmission time of a beacon to be transmitted next. When the IBSS is defined, the wireless communication apparatuses STA1, STA2, and STA3 determine TBTT at regular intervals after the negotiation. For this reason, when there is no need for reception, each wireless communication device can enter a sleep state by turning off the power of the transmission / reception unit until the next time or a plurality of TBTTs ahead.

  Next, with reference to FIG. 2, a beacon transmission procedure by the wireless communication apparatus in the embodiment of the present invention will be described. Each wireless communication device participating in the wireless communication network transmits a beacon at a predetermined interval in order to notify the other wireless communication device of its own existence. In the following description, it is assumed that the beacon transmission interval (beacon transmission cycle) is 80 (msec). This beacon transmission cycle is defined here as a superframe cycle. Note that the superframe period is not limited to 80 (msec).

  A wireless communication device participating in a wireless communication network receives a beacon transmitted from another wireless communication device and checks the information of the other wireless communication device included in the beacon, and sets the timing for transmitting its own beacon. To do. Specifically, the beacon is at a timing almost in the middle of the longest beacon interval within a range that can be received by itself so that it does not collide with a beacon transmitted by another wireless communication device already arranged within the superframe period. Start sending.

  For example, in FIG. 2A, when only one wireless communication device participates in the wireless communication network, the wireless communication device STA1 can start transmitting the beacon B01 at an appropriate timing.

  Next, as shown in FIG. 2B, the wireless communication device STA2 newly participating in the wireless communication network receives the beacon B01 transmitted from the wireless communication device STA1 and confirms the presence of the wireless communication device STA1. The self beacon B02 is transmitted at a timing in the middle of the transmission interval of the beacon B01 transmitted from the wireless communication apparatus STA1.

  Further, as shown in FIG. 2C, the wireless communication device STA3 that participates in the wireless communication network next receives the beacons B01 and B02 transmitted from the wireless communication device STA1 and the wireless communication device STA2, and receives the beacon B01. The self-beacon B03 is transmitted at a timing almost in the middle of the time period from when the beacon is transmitted until the beacon B02 is transmitted.

  Thus, a wireless communication device participating in a wireless communication network can prevent a beacon collision by setting its own beacon transmission timing so that it does not collide with an existing beacon arrangement within a superframe period. . In addition, by transmitting your own beacon in the middle of the longest beacon interval within the range that you can hear, the beacon transmission timing of each wireless communication device is distributed within the superframe period, increasing the transmission efficiency. Can do.

  Next, a method for media access control in the present embodiment will be described with reference to FIG. First, a transmission priority section TPP (Transmission Prioritized Period) will be described with reference to FIG. The transmission priority section TPP is a section in which a wireless communication apparatus having a priority transmission right is allowed to transmit data at a shorter frame interval than other wireless communication apparatuses. This transmission priority section TPP is hereinafter referred to as a “priority slot”. FIG. 3 shows an example in which priority slots are given to wireless communication apparatuses STA1, STA2, and STA3 that transmitted beacons for a predetermined time after beacons B01, B02, and B03 are transmitted in the superframe period, respectively. It was.

  As shown in FIG. 3, each priority slot starts immediately after transmission of the beacons B01, B02, and B03, and ends at a time when a certain period has elapsed. Since each wireless communication device STA1, STA2, and STA3 transmits a beacon every superframe cycle, basically, a priority slot with the same time rate is given to each wireless communication device STA1, STA2, and STA3. It becomes. A contention period (out of priority slots of one wireless communication device and in which a fair transmission opportunity is given to all the wireless communication devices STA1, STA2, and STA3 until another wireless communication device transmits a beacon ( FAP: Fairy Access Period). In the contention section FAP, fair media access control is performed by a normal CSMA / CA method or the like.

  FIG. 3 shows an example in which each priority slot starts immediately after the transmission of the beacon. However, the priority slot is not limited to this. For example, the priority slot may be set at a relative position from the transmission time of the beacon. . For example, the priority slot may be defined in the form of 480 (μsec) from TBTT.

  In the example shown in FIG. 3, since the wireless communication apparatus STA1 transmits the beacon B01 at the head position of the superframe period, the fixed slot immediately after the beacon B01 transmission is a priority slot of the wireless communication apparatus STA1. After that, until the beacon B02 is transmitted from the wireless communication apparatus STA2, the contention section FAP is established, and the fixed period immediately after the transmission of the beacon B02 is the priority slot of the wireless communication apparatus STA2. And until beacon B03 is transmitted, it becomes competition area FAP again, and the fixed period immediately after transmission of beacon B03 becomes a priority slot of radio | wireless communication apparatus STA3.

  FIG. 4 is a diagram showing an example of a beacon format in the embodiment of the present invention. FIG. 4A shows a packet format. In the present embodiment, transmission data is transmitted by a packet. The packet includes a preamble, a heading area, and a payload part (PSDU: PHY Service Data Unit).

  The preamble indicates the presence of a packet and is composed of a unique word. Each wireless communication device can detect whether the wireless communication path is busy or idle by detecting the preamble. The heading area stores the payload portion transmission rate if the attribute, length, transmission power, and physical layer protocol (PHY) of the packet are in the multi-transmission rate mode. The payload part is composed of a MAC header and an MSDU (MAC Service Data Unit). This is a packet configuration when transmitting general data.

  When transmitting a beacon, information for notifying that this packet is a beacon is described in the heading area, and information desired to be notified by a beacon is described in the payload part PSDU. In the example shown in FIG. 4A, as beacon information, a TA (Transmitter Address) field that is an address that uniquely indicates a wireless communication device of a transmission source station, a Type field that indicates the type of this beacon, The TOI (TBTT Offset Indication) field that is information indicating the TBTT offset value in the transmitted superframe period, the NBOI (Neighboring Beacon Offset Information) field that is reception time information of beacons that can be received from neighboring wireless communication devices, NBAI (Neighboring Beacon Activity Information), which is information indicating when the station is receiving the beacon signal transmitted at the time, and the exclusion assigned to the beacon when transmitting a plurality of beacons within this superframe period A serial field indicating a unique serial number and a current In addition, a TIM (Traffic Indication Map) field, which is information notifying to whom this wireless communication apparatus has information, and additional information 100 and the like as a field specific to the proxy beacon in the embodiment of the present invention are included. It is.

  Here, the NBOI field included in the beacon information is information describing the positions (reception times) of beacons of peripheral stations that can be received by the own station within the superframe period. For example, when it is possible to arrange a maximum of 16 beacons within one superframe period, as shown in FIG. 4A, in the NBOI field, information on the arrangement of beacons that can be received is a 16-bit long bit. Describe in map format. That is, while mapping to the first bit of the NBOI field with reference to the transmission time of the regular beacon of the local station, the position (reception time) of the beacon that can be received by the local station is set to the relative position from the transmission time of the regular beacon of the local station. 1 is written in the bit corresponding to the relative position (offset) of the normal or auxiliary beacon of the local station and the relative position (offset) of the beacon that can be received, and the bit position corresponding to the other relative position is 0. Leave as it is.

  For example, as shown in FIG. 4A, when the wireless communication device 0 creates an NBOI field such as “1100000001,000,000” in a communication environment in which up to 16 wireless communication devices 0 to F are accommodated. Is notified that “the beacon from the wireless communication device 1 and the wireless communication device 9 can be received”. That is, regarding the bit corresponding to the relative position of the beacon that can be received, “1” is marked when the beacon is receivable, and “0”, that is, a space is allocated when it is not received. By referring to this NBOI field, the number of wireless communication devices participating in the wireless communication network can be grasped. In the case shown in FIG. 4A, it can be seen that three wireless communication devices including themselves participate in the wireless communication network.

  Further, by referring to this NBOI field, it is possible to grasp the position (reception time) of a beacon that is not used. Any one of the unused beacon positions (reception times) is assigned as a later-described proxy beacon position (reception time).

  There are two types of beacons described in the invention in the embodiment of the present invention, which are defined as “normal beacons” and “proxy beacons”. The normal beacon is a beacon in which the additional information 100 in FIG. 4A is not included in the beacon format, for example. In addition, a normal beacon is transmitted one by one from each wireless communication device that constitutes a wireless network within a superframe period, and by this normal beacon, each wireless communication device identifies itself as another wireless communication device. To inform.

  On the other hand, the proxy beacon is a beacon of the same type as the auxiliary beacon in the prior art shown in FIG. 12, but in order to acquire a priority slot in which other wireless communication devices can preferentially transmit data. A beacon used. In the case of a conventional auxiliary beacon, the wireless communication device itself that transmitted the auxiliary beacon acquires the priority slot, and itself transmits data preferentially in the priority slot. However, the proxy in the embodiment of the present invention In the case of a beacon, the wireless communication device itself that transmitted the proxy beacon acquires the priority slot, but the priority slot is assigned to another wireless communication device, and data is transmitted to the wireless communication device different from itself in the priority slot. It is something to be made. The format of the proxy beacon is assumed to be obtained by adding the additional information 100 in FIG. 4A to the normal beacon format, for example. The required number of proxy beacons can be issued within the superframe period. It should be noted that the normal beacon and the proxy beacon are common in that the priority slot is acquired after the beacon is transmitted as described in FIG.

  FIG. 4B is a diagram illustrating an example of the configuration of the additional information 100. The additional information 100 includes a proxy beacon identifier 101, a transmission request 102, and an assignment destination 103. The proxy beacon identifier 101 is an identifier indicating that the beacon is a proxy beacon. By this proxy beacon identifier 101, it is recognized in another wireless communication device that the beacon is a proxy beacon.

  The transmission request 102 describes a request for permitting transmission of transmission data or a request for prohibiting transmission of transmission data. If there is a vacancy in the reception buffer of the wireless communication device that receives the transmission data, a request for permitting transmission of the transmission data is described. However, there is a vacancy in the reception buffer of the wireless communication device that receives the transmission data. If not, a request not to allow transmission of transmission data is described. The request to permit transmission data transmission or the request to not allow transmission data transmission is set to “0” when transmission data transmission is not permitted, and “0” when transmission data transmission is permitted. 1 ". Further, the remaining amount of the reception buffer may be indicated instead of indicating whether transmission of transmission data is permitted. In this case, the wireless communication apparatus that has received it determines whether or not to transmit transmission data, and determines the amount of data when transmitting the transmission data.

  By including this transmission request 102 in the proxy beacon, according to the IEEE 802.11 standard, a request such as a transmission request or a transmission stop request transmitted after the exchange such as RTS and CTS is not exchanged such as RTS and CTS. This can be done simply by transmitting a proxy beacon to the communication band.

  The allocation destination 103 describes information for specifying a wireless communication apparatus that uses a priority slot acquired by transmission of a proxy beacon. It is assumed that the information specifying the wireless communication device is described by a unique ID. For example, a MAC (Media Access Control address) address may be used as the unique ID.

  FIG. 5 is a diagram illustrating an example of a configuration of the wireless communication apparatus 200 that transmits a proxy beacon according to the embodiment of the present invention. The wireless communication apparatus 200 includes an antenna 201, a reception unit 202, an output request determination unit 203, a communication information analysis unit 204, a communication information holding unit 205, a reception buffer 206, a slot number determination unit 207, and a priority slot. An acquisition unit 208, a reception buffer monitoring unit 209, a proxy beacon generation unit 210, a periodic beacon generation unit 211, and a transmission unit 212 are provided.

  The antenna 201 plays a role of radiating radio waves into the space or capturing radio waves transmitted through the space. The receiving unit 202 mainly performs decoding and demodulation processing on the data received from the antenna 201. The output request determination unit 203 determines whether data transmitted from another wireless communication device is a request for output of a proxy beacon. As a result of the determination, if the data transmitted from another wireless communication device is a request for the output of a proxy beacon, the output request determination unit 203 supplies the data to the slot number determination unit 207. When the data transmitted from another wireless communication device does not request the output of the proxy beacon, the output request determination unit 203 supplies the data to the communication information analysis unit 204.

  The communication information analysis unit 204 analyzes information included in the supplied data. When the content of the data supplied as a result of the analysis is information relating to another wireless communication device in a network such as a normal beacon, for example, the communication information analysis unit 204 causes the communication information holding unit 205 to hold the information. On the other hand, when the content of the supplied data is data such as image data, it is supplied to the reception buffer 206.

  The communication information holding unit 205 holds data from the communication information analysis unit 204. This content includes, for example, information related to the position (reception time) of the beacon used by each wireless communication device constituting the network as described in the NBOI field shown in FIG. The reception buffer 206 is a storage area for temporarily storing data supplied from the communication information analysis unit 204 to compensate for differences in processing speed and transfer speed. Data stored in the reception buffer 206 is sequentially output at an appropriate transfer rate.

  The slot number determination unit 207 determines the necessary number of priority slots from the data rate and latency necessary for transmitting data included in the data transmitted from the wireless communication device that requests the output of the proxy beacon. . Here, the data rate refers to the amount of data transferred per hour. In addition, the latency is a delay time required from when a data request is made until the data is actually transferred. If the data rate in one slot is determined in advance, the required number of slots can be determined based on the transmitted data rate, latency, and the like.

  The priority slot acquisition unit 208 refers to the communication information holding unit 205 to grasp the communication status, and the beacon position (reception time) as a premise for obtaining the priority slots by the number of slots determined by the slot number determination unit 207 Is something to get. The communication information holding unit 205 holds the position (reception time) of the beacon used in each wireless communication device, and the priority slot acquisition unit 208 stores the position (reception time of the beacon not used in each wireless communication device). ) To get. The priority slot acquisition unit 208 supplies information on the position (reception time) of the selected beacon to the proxy beacon generation unit 210. Further, the priority slot acquisition unit 208 transmits information about the position (reception time) of the selected beacon to another wireless communication device.

  The reception buffer monitoring unit 209 monitors the reception buffer, and supplies to the proxy beacon generation unit 210 whether or not there is a vacancy in the reception buffer and how much is available. Since the reception buffer monitoring unit 209 can inform the transmission buffer of the status of the reception buffer, it is possible to prevent the reception buffer from overflowing.

  The proxy beacon generation unit 210 generates a proxy beacon from the information supplied from the reception buffer monitoring unit 209 and the information such as the MAC address of the wireless communication apparatus that has requested the proxy beacon, and is supplied from the priority slot acquisition unit 208 The proxy beacon is transmitted at the timing of the beacon position (reception time). The transmission priority section TPP after transmitting this proxy beacon can be transmitted as a priority slot. That is, the priority slot is acquired after transmitting the proxy beacon.

  The periodic beacon generator 211 generates and transmits a normal beacon. The normal beacon generated by the periodic beacon generation unit 211 is transmitted at a superframe period. The transmission unit 212 encodes and modulates data to be transmitted.

  FIG. 6 is a diagram illustrating an example of a configuration of the wireless communication device 300 that receives a proxy beacon. The wireless communication apparatus 300 includes an antenna 301, a reception unit 302, a priority slot allocation detection unit 303, an allocation destination determination unit 304, a transmission request determination unit 305, a transmission timing control unit 306, a data generation unit 307, A priority slot acquisition unit 308 and a transmission unit 309 are provided. The antenna 301, the reception unit 302, and the transmission unit 309 have the same functions as the antenna 201, the reception unit 202, and the transmission unit 212 in FIG.

  The priority slot allocation detection unit 303 detects the proxy beacon identifier 101 from the received data. That is, the priority slot allocation detection unit 303 determines whether or not the received data is a proxy beacon. When the proxy beacon identifier 101 is detected from the received data, the data is supplied to the assignment destination determination unit 304. When the proxy beacon identifier 101 is not detected from the received data, the received data is not a proxy beacon, and therefore processing is performed on a normal beacon or data.

  The allocation destination determination unit 304 determines whether or not the wireless communication device that can use the priority slot in the received proxy beacon is itself. This determination is made based on, for example, the description content of the assignment destination 103 described with reference to FIG. When a MAC address is described in the assignment destination 103, it is determined whether or not the MAC address matches its own MAC address. As a result of the determination, if the MAC address matches its own MAC address, the fact that the proxy beacon and the address match is supplied to the transmission request determination unit 305. As a result of the determination, if the MAC address does not match the own MAC address, the priority slot associated with the proxy beacon cannot be used preferentially. In this case, the transmission request determination unit 305 is supplied that the proxy beacon and the address do not match.

  The transmission request determination unit 305 determines whether data transmission is permitted based on information included in the received proxy beacon. This is determined by, for example, the description content of the transmission request 102 described with reference to FIG. When the fact that the addresses match is supplied from the assignment destination determination unit 304 and data transmission is permitted, the transmission request determination unit 305 instructs the data generation unit 307 to supply data to the transmission unit 309. To do. For example, if there is a remaining amount of the reception buffer in the description content of the transmission request 102 described with reference to FIG. 4B, the data generation unit 307 is instructed on the amount of data to be transmitted based on the remaining amount of the reception buffer.

  When the fact that the addresses match is supplied from the assignment destination determination unit 304 and when data transmission is not permitted, the transmission request determination unit 305 causes the transmission timing control unit 306 to stop transmitting data. To inform. On the other hand, when it is supplied from the assignment destination determination unit 304 that the addresses do not match and the transmission of data is not permitted, the transmission request determination unit 305 notifies the priority slot acquisition unit 308 to that effect.

  The transmission timing control unit 306 generates and controls data transmission timing. This timing is generated based on information about the position (reception time) of the beacon selected on the side of generating the proxy beacon. In addition, you may comprise the information about the position (reception time) of a beacon as what is transmitted from the radio | wireless communication apparatus which produces | generates a proxy beacon. By doing so, there is an advantage that power consumption can be reduced because unnecessary beacons need not be received.

  Further, the wireless communication device 300 itself may be configured to acquire information about the position (reception time) of the beacon with reference to the NBOI field included in the normal beacon or the like. If there is a notification from the transmission request determination unit 305 that data transmission is to be stopped, the data transmission is stopped.

  The data generation unit 307 generates data and supplies the data to the transmission unit 309 according to an instruction from the transmission request determination unit 305. The priority slot acquisition unit 308 determines that the allocation destination determination unit 304 determines that the allocation destination of the priority slot is not itself, and the transmission request determination unit 305 determines that there is information indicating that data transmission is not permitted. This is notified and priority slots are acquired in accordance with the CSMA / CA system.

  That is, if it is determined that the priority slot is not assigned to itself and there is information indicating that data transmission is not permitted, the received proxy beacon is a proxy beacon assigned to another wireless communication device. In addition, the wireless communication device on the data receiving side is in a state where data cannot be transmitted because there is no empty reception buffer. In this case, since the wireless communication apparatus to which the priority slot is assigned cannot transmit data, the period of this priority slot is vacant. In this case, according to the CSMA / CA method, other wireless communication devices compete for the priority slot. For this purpose, the priority slot acquisition unit 308 is provided.

  In the embodiment of the present invention, the transmission request 102 is not decoded for a proxy beacon including information that the priority slot is not assigned to itself. The transmission request 102 included in the proxy beacon is not decoded in the wireless communication device, and information indicating that data transmission is not permitted is included in the proxy beacon when data transmission is not performed for a predetermined period from the start timing of the priority slot. The other wireless communication devices compete for the priority slot according to the CSMA / CA method. Thus, the power consumption can be reduced by not decoding the transmission request 102. However, the present invention is not limited to this, and after the transmission request 102 included in the proxy beacon is decoded in the wireless communication apparatus and it is determined that there is information indicating that transmission of data is not permitted, according to the CSMA / CA system, Other wireless communication devices may compete for the priority slot.

  FIG. 7 is a diagram showing a data flow when communication is performed using wireless communication apparatuses STA1 and STA2 according to the embodiment of the present invention. The wireless communication apparatus STA1 has the function of the wireless communication apparatus 300 in FIG. 6, and the wireless communication apparatus STA2 has the function of the wireless communication apparatus 200 in FIG. In FIG. 7, “B” represents a normal beacon, “AB” represents a proxy beacon, and “D” represents data.

  The period from the normal beacon 401 to the normal beacon 404 on the transmission side of the wireless communication apparatus STA1 and the period from the normal beacon 511 to the normal beacon 515 on the transmission side of the wireless communication apparatus STA2 are superframe periods. As described in FIG. 2, the timing at which the normal beacon is transmitted is a timing corresponding to the middle between adjacent normal beacons so as not to interfere with others as much as possible. Also in FIG. 7, the normal beacon 511 on the transmission side of the wireless communication apparatus STA2 is located at a position corresponding to the middle between the normal beacon 401 and the normal beacon 404 on the transmission side of the wireless communication apparatus STA1.

  When the normal beacon 401 on the transmission side of the wireless communication apparatus STA1 is transmitted, the transmission priority section TPP immediately after that is given priority as a priority slot, and the data communication priority is given to the wireless communication apparatus STA1, and the data 402 is transmitted. This is received as a normal beacon 501 and data 502 in the wireless communication apparatus STA2. Next, after a predetermined time elapses, a normal beacon 511 is transmitted from the wireless communication device STA2, and the transmission priority section TPP immediately after that is given a priority for data transmission to the wireless communication device STA2 as a priority slot, and data 512 is transmitted. . This is received as a normal beacon 411 and data 412 in the wireless communication apparatus STA1. The same applies to other normal beacons. That is, the normal beacon 404 and the data 405 transmitted from the wireless communication apparatus STA1 are received as the normal beacon 504 and the data 505 by the wireless communication apparatus STA2, respectively. Further, the normal beacon 515 and the data 516 transmitted from the wireless communication apparatus STA2 are received as the normal beacon 415 and the data 416 by the wireless communication apparatus STA1, respectively.

  In the wireless communication apparatus STA1, when moving image data or the like is to be transmitted continuously without delay, only the priority slot acquired by the normal beacon is insufficient. In this case, the wireless communication device STA1 issues a request to the wireless communication device STA2 for issuing a proxy beacon. In response to this request, the wireless communication apparatus STA2 selects a beacon position (reception time) that is not used by any wireless communication apparatus based on the information obtained from the normal beacon, and selects an appropriate beacon position (reception time) from that position. ) To issue a proxy beacon. A plurality of beacon positions (reception times) may be selected.

  In addition, although it is selection of this beacon position, a beacon position is selected based on data, such as a data rate and latency transmitted from radio | wireless communication apparatus STA1. For example, when the wireless communication apparatus STA1 does not transmit a clear image, it is not necessary to select so many beacon positions (reception times) because the data rate is low. In addition, if a real-time video with no time delay is required, the latency is reduced, and therefore the beacon position interval is selected to be narrow in the selection of the beacon position (reception time).

  In FIG. 7, the wireless communication device STA2 that has received the request from the wireless communication device STA1 issues a proxy beacon 513, and when the wireless communication device STA1 receives this as the proxy beacon 413, the transmission priority section TPP immediately after that is prioritized. The priority of data transmission is given to the wireless communication apparatus STA1 as a slot, and data 403 is transmitted. The data is received as data 503 in the wireless communication apparatus STA2. Similarly, the wireless communication device STA2 that has received the request from the wireless communication device STA1 issues a proxy beacon 514. When the wireless communication device STA1 receives this as the proxy beacon 414, the transmission priority section TPP immediately after that is wirelessly set as a priority slot. Data communication priority is given to the communication device STA1, and data 406 is transmitted. The data is received as data 506 in the wireless communication apparatus STA2.

  Although not shown, at the time of data transmission, the data is transmitted according to the above-mentioned IEEE 802.11 standard.

  FIG. 8 shows data in communication of wireless communication apparatuses STA1 and STA2 when the reception buffer of wireless communication apparatus STA2 runs out when communication is performed using wireless communication apparatuses STA1 and STA2 in the embodiment of the present invention. It is a figure which shows the flow of.

  When the normal beacon 601 on the transmission side of the wireless communication apparatus STA1 is transmitted, the transmission priority section TPP immediately after that is given a priority for data transmission to the wireless communication apparatus STA1 as a priority slot, and data 602 is transmitted. This is received as a normal beacon 701 and data 702 by the wireless communication apparatus STA2. In accordance with a request from the wireless communication device STA1, the wireless communication device STA2 transmits a proxy beacon 711 at an appropriate beacon position (reception time), and the wireless communication device STA1 that has received this as the proxy beacon 611 transmits immediately after that. The priority section TPP is given a priority for data transmission to the wireless communication apparatus STA1 as a priority slot, and data 603 is transmitted. The wireless communication apparatus STA2 receives it as data 703.

  Assume that after the wireless communication device STA2 transmits the normal beacon 712 and data 713 and the wireless communication device STA1 receives them as the normal beacon 612 and data 613, the reception buffer of the wireless communication device STA2 has run out. When the wireless communication device STA2 receives data even though its own reception buffer is not empty, the reception buffer overflows and data is lost. For this reason, the radio communication apparatus STA2 issues a request not permitting data transmission (hereinafter referred to as a data transmission stop request) in accordance with an instruction from the reception buffer monitoring unit 209.

  In the embodiment of the present invention, this data transmission stop request is included in the proxy beacon. This can be realized, for example, in the transmission request 102 described with reference to FIG. The wireless communication device STA2 sends a proxy beacon 714 including a data transmission stop request to the wireless communication device STA1 when the reception buffer becomes empty, and the wireless communication device STA1 receives this as a data transmission stop request 614. When receiving this, the wireless communication apparatus STA1 does not transmit data. This state is indicated by dotted lines at reference numerals 604 and 704 in FIG.

  Note that, in the priority slots in the reference numerals 604 and 704, wireless communication apparatuses (not shown) acquire the priority slot section and transmit data according to the CSMA / CA scheme.

  Thereafter, even if the normal beacon 605 is transmitted in the wireless communication apparatus STA1, data cannot be transmitted because a transmission stop request is issued. The wireless communication device STA2 receives only the normal beacon 705. This state is represented by dotted lines at reference numerals 606 and 706 in FIG. The priority slots in the reference numerals 606 and 706 are also transmitted between wireless communication apparatuses (not shown) according to the CSMA / CA scheme to acquire the priority slot section and transmit data.

  When the reception buffer of the wireless communication device STA2 is vacant, the wireless communication device STA2 issues a request for permitting data transmission to the wireless communication device STA1 (hereinafter referred to as a data transmission request). In the embodiment of the present invention, this data transmission request is also included in the proxy beacon. This can be realized in the transmission request 102 described with reference to FIG. 4A, for example, as in the case of the data transmission stop request.

  The wireless communication apparatus STA2 issues a proxy beacon 715 including a data transmission request when its reception buffer is free. The wireless communication apparatus STA1 receives this as the proxy beacon 615, and the transmission priority section TPP immediately after that is given priority to the wireless communication apparatus STA1 as a priority slot, and data 607 is transmitted. This is received as data 707 in the wireless communication apparatus STA2.

  Next, the operation of the wireless communication apparatus according to the embodiment of the present invention will be described with reference to the drawings.

  FIG. 9 is a diagram showing a flow of processing after a proxy beacon request is made in the wireless communication apparatus according to the embodiment of the present invention. When a request for a proxy beacon is received (S911), the number of slots necessary for transmission of data to be transmitted is determined based on information included in the request for a proxy beacon (S912), and priority slots are acquired by the number of slots. The position (reception time) of the beacon that is the premise to be selected is selected (S913). The selection of the beacon position (reception time) on which the priority slot is acquired is specifically selected from beacon positions (reception time) that are not used in the superframe period.

  The proxy beacon is transmitted at the timing of the beacon position (reception time) that is a precondition for acquiring the selected priority slot (S914). The interval between the transmission priority sections TPP immediately after the proxy beacon is received by another wireless communication apparatus corresponds to the priority slot. In this priority slot, the wireless communication device that has requested the proxy beacon transmits data (S915). It is determined whether or not the reception buffer in the wireless communication apparatus that has received the data is being monitored, and whether or not there is an empty reception buffer (S916).

  If it is determined that there is an empty reception buffer, it is determined whether or not there is a request for canceling the transmission of the proxy beacon (S917). If there is a request for canceling the transmission of the proxy beacon, the process ends. On the other hand, if there is no request for canceling the transmission of the proxy beacon, the process returns to step S914 to be processed.

  If it is determined that there is no space in the reception buffer, a proxy beacon including a data transmission stop request, which is a request not permitting data transmission, is transmitted (S918), and the wireless communication apparatus that has transmitted the data Stop sending Even after the proxy beacon including the data transmission stop request is transmitted, the reception buffer is monitored (S918), and when the reception buffer is free, the process returns to step S914 to perform the process.

  FIG. 10 is a diagram illustrating a process flow after the proxy beacon is received in the wireless communication apparatus according to the embodiment of the present invention. When a beacon is received (S921), it is determined whether this beacon is a proxy beacon (S922). For example, when the beacon format is the form described with reference to FIG. 4, whether the beacon is a proxy beacon can be determined by referring to the proxy beacon identifier 101 in the additional information 100.

  If it is determined in step S922 that the received beacon is a proxy beacon, it is determined whether or not the priority slot is assigned by the proxy beacon (S923). For example, when the format of the beacon is the form described in FIG. 4, it can be determined whether or not the allocation destination is itself by referring to the allocation destination 103 in the additional information 100.

  If it is determined in step S923 that the priority slot is assigned to itself, it is determined whether or not data transmission is permitted (S924). For example, when the beacon format is the form described with reference to FIG. 4, it can be determined whether or not data transmission is permitted by referring to the transmission request 102 in the additional information 100.

  If it is determined in step S924 that data transmission is permitted, a data transmission timing is generated (S925). Specifically, the timing for transmitting this data is generated based on the position (reception time) of the beacon that is the premise of the priority slot.

  If the data transmission timing is determined, the data is generated and transmitted according to the timing (S926). If the remaining amount of the reception buffer is included as information in the transmission request 102, the amount of data to be transmitted is determined based on the remaining amount of the reception buffer, and data transmission is performed. This data transmission is performed during the above-described transmission priority section TPP corresponding to the priority slot. After this transmission priority section TPP elapses, communication is performed, for example, according to the CSMA / CA method.

  Steps S921 to S926 are repeated until transmission of data to be transmitted is completed (S927), and when transmission of data to be transmitted is completed, a request to cancel transmission of the proxy beacon is transmitted (S928).

  FIG. 11 is a diagram showing a flow of processing when communication is performed in the wireless communication device STA1 and the wireless communication device STA2 in the embodiment of the present invention. The wireless communication device STA1 has the function of the wireless communication device 300 in FIG. 6, and the wireless communication device STA2 has the function of the wireless communication device 200 in FIG.

  The wireless communication apparatus STA1 transmits a proxy beacon output request 1001 that is a request to output a proxy beacon to the wireless communication apparatus STA2. The proxy beacon output request 1001 includes information such as data rate and latency. The wireless communication apparatus STA2 determines how many proxy beacons are set at which beacon position (reception time) in the superframe period based on information such as a data rate and latency. The wireless communication device STA2 includes the determined information in the proxy beacon output response 2001 and transmits the information to the wireless communication device STA1.

  The wireless communication apparatus STA2 transmits the proxy beacon 2002 at the timing of the beacon position (reception time) that has previously determined the proxy beacon. The wireless communication apparatus STA1 that has received the proxy beacon transmits data 1002 using the priority slot immediately after the proxy beacon. Thereafter, communication is performed in accordance with, for example, the CSMA / CA system. Thereafter, when the timing of the previously determined beacon position (reception time) comes, the wireless communication device STA2 transmits the proxy beacon 2003 again. Receiving this, the wireless communication apparatus STA1 transmits data 1003 again using the priority slot immediately after the proxy beacon 2003 in the same manner as described above.

  It is assumed that it is detected that the reception buffer in the wireless communication device STA2 is full while the communication as described above is performed in the wireless communication devices STA1 and STA2. In this case, the wireless communication apparatus STA2 transmits a proxy beacon 2004 including a data transmission stop request to the wireless communication apparatus STA1. When the proxy beacon 2004 is received, the wireless communication apparatus STA1 analyzes the proxy beacon 2004, recognizes that the wireless communication apparatus STA2 does not allow data transmission, and does not transmit data.

  Thereafter, when it is detected in the wireless communication device STA2 that the reception buffer is empty, the wireless communication device STA2 transmits a proxy beacon 2005 including a data transmission request to the wireless communication device STA1. The wireless communication apparatus STA1 that has received the proxy beacon 2005 transmits data 1004 again using the priority slot immediately after the proxy beacon 2005 in the same manner as described above.

  When there is no more data to be transmitted in the wireless communication apparatus STA1 during the communication as described above, the wireless communication apparatus STA1 wirelessly sends a proxy beacon release request 1005 that is a request to cancel communication using the proxy beacon. It transmits to communication apparatus STA2. The wireless communication apparatus STA2 that has received the proxy beacon cancellation request 1005 transmits a proxy beacon cancellation response 2006 and stops transmitting the proxy beacon.

  The embodiment of the present invention is an example for embodying the present invention and has a corresponding relationship with the invention-specific matters in the claims as shown below, but is not limited thereto. However, various modifications can be made without departing from the scope of the present invention.

  That is, in claim 1, the slot number determining means corresponds to the slot number determining unit 207, for example. A communication information holding unit corresponds to the communication information holding unit 205, for example. The priority slot acquisition unit corresponds to the priority slot acquisition unit 208 and the proxy beacon generation unit 210, for example. The priority slot allocation means corresponds to the proxy beacon generator 210, for example. The priority slot allocation detection means corresponds to the priority slot allocation detection unit 303, for example. The assignment destination determination unit corresponds to, for example, the assignment destination determination unit 304. Data generation means corresponds to the data generation unit 307, for example. The transmission timing control means corresponds to the transmission timing control unit 306, for example. A transmission unit corresponds to the transmission unit 309.

  Further, in claim 2, the slot number determining means corresponds to the slot number determining unit 207, for example. A communication information holding unit corresponds to the communication information holding unit 205, for example. The priority slot acquisition unit corresponds to the priority slot acquisition unit 208 and the proxy beacon generation unit 210, for example. The priority slot allocation means corresponds to the proxy beacon generator 210, for example.

  Further, in claim 4, the beacon generation means corresponds to, for example, the proxy beacon generation unit 210 and the periodic beacon generation unit 211.

  Further, in claim 5, proxy beacon generation means corresponds to the proxy beacon generation unit 210, for example. Further, the periodic beacon generating means corresponds to the periodic beacon generating unit 211, for example.

  Further, in claim 8, the reception buffer corresponds to the reception buffer 206, for example. The reception buffer monitoring means corresponds to the reception buffer monitoring unit 209, for example.

  In claim 11, receiving means corresponds to the receiving unit 302, for example. The assignment destination determination unit corresponds to, for example, the assignment destination determination unit 304. Data generation means corresponds to the data generation unit 307, for example. The transmission timing control means corresponds to the transmission timing control unit 306, for example. A transmission unit corresponds to the transmission unit 309, for example.

  In claim 13, the transmission request determination unit corresponds to, for example, the transmission request determination unit 305.

    Further, in claim 16, receiving means corresponds to the receiving unit 302, for example. The assignment destination determination unit corresponds to, for example, the assignment destination determination unit 304. Data generation means corresponds to the data generation unit 307, for example. A transmission request determination unit corresponds to the transmission request determination unit 305, for example. The priority slot acquisition means corresponds to the priority slot acquisition unit 308, for example. The transmission timing control means corresponds to the transmission timing control unit 306, for example. A transmission unit corresponds to the transmission unit 309, for example.

  Further, in claim 17, the slot number determining procedure corresponds to, for example, step S912. The priority slot acquisition procedure corresponds to, for example, step S913 and step S914. The priority slot allocation procedure corresponds to, for example, step S914.

  In claim 18, the reception procedure corresponds to, for example, step S921. The assignment destination determination procedure corresponds to, for example, step S923. The data generation procedure corresponds to, for example, step S926. The transmission timing control procedure corresponds to, for example, step S925 and step S926. The transmission procedure corresponds to, for example, step S926.

  Further, in claim 19, the slot number determining step corresponds to, for example, step S912. The priority slot acquisition step corresponds to, for example, step S913 and step S914. The priority slot allocation step corresponds to, for example, step S914.

  In claim 20, the reception step corresponds to step S921, for example. Also, the assignment destination determination step corresponds to step S923, for example. The data generation step corresponds to, for example, step S926. The transmission timing control step corresponds to, for example, step S925 and step S926. The transmission step corresponds to, for example, step S926.

  The processing procedure described in the embodiment of the present invention may be regarded as a method having a series of these procedures, and a program for causing a computer to execute these series of procedures or a recording medium storing the program May be taken as

It is a figure which shows the structure of the radio | wireless communications system constructed | assembled using the radio | wireless communication apparatuses 200 and 300 in embodiment of this invention. It is a figure which shows the transmission procedure of the beacon by the radio | wireless communication apparatus in embodiment of this invention. It is a figure which shows arrangement | positioning of the transmission priority area (TPP) in embodiment of this invention. It is a figure which shows an example of the format of the beacon in embodiment of this invention. It is a figure which shows an example of a structure of the radio | wireless communication apparatus 200 which transmits the proxy beacon in embodiment of this invention. It is a figure which shows an example of a structure of the radio | wireless communication apparatus 300 which receives a proxy beacon. It is a figure which shows the flow of data at the time of communicating using radio | wireless communication apparatus STA1 and STA2 in embodiment of this invention. The data flow in communication of radio | wireless communication apparatuses STA1 and STA2 when the reception buffer of radio | wireless communication apparatus STA2 runs out in the case where it communicates using radio | wireless communication apparatus STA1 and STA2 in embodiment of this invention is shown. FIG. It is a figure which shows the flow of a process after a proxy beacon request | requirement is made in the radio | wireless communication apparatus in embodiment of this invention. It is a figure which shows the flow of a process after receiving a proxy beacon in the radio | wireless communication apparatus in embodiment of this invention. It is a figure which shows the flow of a process when communication is performed in radio | wireless communication apparatus STA1 and radio | wireless communication apparatus STA2 in embodiment of this invention. It is a figure which shows the data flow by the radio | wireless communication in the radio | wireless communication apparatus STA1 and radio | wireless communication apparatus STA2 by the conventional ad hoc mode.

Explanation of symbols

100 Additional information 101 Proxy beacon identifier 102 Transmission request 103 Allocation destination 200, 300 Wireless communication device 201, 301 Antenna 202, 302 Reception unit 203 Output request determination unit 204 Communication information analysis unit 205 Communication information holding unit 206 Reception buffer 207 Determination of slot number Unit 208 Priority slot acquisition unit 209 Reception buffer monitoring unit 210 Proxy beacon generation unit 211 Periodic beacon generation unit 212, 309 Transmission unit 303 Priority slot allocation detection unit 304 Allocation destination determination unit 305 Transmission request determination unit 306 Transmission timing control unit 307 Data Generation unit 308 Priority slot acquisition unit

Claims (20)

A wireless communication system including a plurality of wireless communication devices,
Slot number determining means for determining the number of slots necessary for transmission of transmission data based on data information including a data rate transmitted from another wireless communication device;
Communication information holding means for holding communication information including the usage status of the slot;
Priority slot acquisition means for acquiring, as many as the number of slots determined by the slot number determination means, priority slots to which the wireless communication apparatus should preferentially transmit data based on the communication information;
A first wireless communication device comprising: priority slot assignment means for transmitting a signal including the fact that the priority slot has been assigned to the other wireless communication device and the timing of the priority slot;
Priority slot allocation detection means for detecting that the priority slot is allocated from the signal;
Assignment destination determination means for determining whether or not the priority slot is assigned to the wireless communication device;
Data generating means for generating the transmission data;
Transmission timing control means for controlling the timing of transmitting the transmission data based on the signal;
A second transmission unit configured to transmit the transmission data based on the control of the transmission timing control unit when it is detected that the priority slot is allocated and it is determined that the priority slot is allocated to the wireless communication apparatus; And a wireless communication apparatus. Slot number determining means for determining the number of slots necessary for data transmission based on data information including a data rate sent from another wireless communication device;
Communication information holding means for holding communication information including the usage status of the slot;
Priority slot acquisition means for acquiring the priority slots to which the wireless communication apparatus should preferentially transmit the data based on the communication information by the number of slots determined by the slot number determination means;
A wireless communication apparatus comprising: priority slot allocation means for allocating the priority slot to the other wireless communication apparatus.   3. The wireless communication apparatus according to claim 2, wherein the priority slot acquisition unit further notifies the other wireless communication apparatus of information including the timing of the priority slot. The priority slot acquisition means includes
Comprising beacon generating means for generating a beacon;
3. The wireless communication apparatus according to claim 2, wherein a predetermined period after transmitting the beacon generated by the beacon generating unit is acquired as the priority slot. The beacon generating means includes
Periodic beacon generating means for generating a beacon at a constant period;
Proxy beacon generating means for generating a beacon triggered by the data information sent from the other wireless communication device;
The wireless communication apparatus according to claim 4, wherein the beacon generated by the beacon generation unit is a beacon generated by the proxy beacon generation unit.   6. The radio communication apparatus according to claim 5, wherein the priority slot allocation means includes in the beacon generated by the proxy beacon generation means that the priority slot is allocated to the other radio communication apparatus.   7. The radio communication apparatus according to claim 6, wherein the priority slot allocation unit further includes information specifying the other radio communication apparatus to which the priority slot is allocated in the beacon generated by the proxy beacon generation unit. . A reception buffer for storing data transmitted from the other wireless communication device;
Receiving buffer monitoring means for requesting the other wireless communication device to permit data transmission or requesting not to permit transmission according to the amount of data stored in the reception buffer; The wireless communication apparatus according to claim 5, wherein:   9. The wireless communication apparatus according to claim 8, wherein the reception buffer monitoring unit includes a data amount that can be further accumulated in the reception buffer in a request for permitting transmission of the data.   9. The wireless communication according to claim 8, wherein the priority slot allocating unit includes a request for permitting transmission of the data or a request for not permitting transmission in the beacon generated by the auxiliary beacon generating unit. apparatus. Receiving means for receiving priority slot data including assigning a priority slot to which the first wireless communication apparatus should preferentially transmit data to the second wireless communication apparatus;
Assignment destination determining means for determining whether or not the wireless communication device corresponds to the second wireless communication device;
Data generation means for generating transmission data;
Transmission timing control means for controlling the timing of transmitting the transmission data based on the timing of the priority slot;
A wireless communication device comprising: a transmission unit configured to transmit the transmission data based on control of the transmission timing control unit when it is determined that the wireless communication device corresponds to the second wireless communication device. .   12. The wireless communication apparatus according to claim 11, wherein the priority slot data is included in a beacon transmitted in response to a request from the second wireless communication apparatus.   Transmitting the transmission data when receiving a request to allow transmission of data from the first wireless communication apparatus, and transmitting not transmitting the transmission data when receiving a request not to allow transmission of data The wireless communication apparatus according to claim 11, further comprising a request determination unit.   14. The transmission request determination unit, when receiving a data amount that can be received by the first wireless communication device from the first wireless communication device, causes a data amount corresponding to the data amount to be transmitted. The wireless communication device described.   12. The wireless communication apparatus according to claim 11, wherein the data generation means requests that the assigned priority slot is unnecessary when there is no transmission data to be transmitted. A request that the first wireless communication device assigns a priority slot to which data should be preferentially transmitted to the second wireless communication device and that the first wireless communication device is allowed to transmit data or not. Receiving means for receiving a beacon including a request to that effect;
Assignment destination determining means for determining whether or not the wireless communication device corresponds to the second wireless communication device;
Data generation means for generating transmission data;
Transmission request determination means for determining whether or not there is a request not to allow transmission of the data to the first wireless communication device;
When it is determined that the wireless communication device does not correspond to the second wireless communication device by the assignment destination determination unit and the transmission request determination unit determines that there is a request not to allow transmission of the data A priority slot acquisition means for acquiring a priority slot;
Transmission timing control means for controlling the timing of transmitting the transmission data based on the timing of the priority slot;
A wireless communication apparatus comprising: transmission means for transmitting the transmission data to a third wireless communication apparatus based on control of the transmission timing control means. A processing method in a wireless communication apparatus for holding communication information including a slot usage state,
A slot number determination procedure for determining the number of slots necessary for data transmission based on data information including a data rate sent from another wireless communication device;
A priority slot acquisition procedure for acquiring, as many as the number of slots determined by the slot number determination procedure, priority slots in which the wireless communication device can preferentially transmit the data based on the communication status;
And a priority slot allocation procedure for allocating the priority slot to the other wireless communication device. A receiving procedure for receiving priority slot data including assigning to the second wireless communication device a priority slot for the first wireless communication device to preferentially transmit data;
An assignment destination determination procedure for determining whether or not the wireless communication device corresponds to the second wireless communication device;
A data generation procedure for generating transmission data;
A transmission timing control procedure for controlling the timing of transmitting the transmission data based on the timing of the priority slot;
A transmission procedure for transmitting the transmission data based on the control of the transmission timing control means when it is detected that the priority slot is allocated and the wireless communication apparatus is determined to correspond to the second wireless communication apparatus; The processing method characterized by comprising. To a wireless communication device that holds communication information including slot usage status,
A slot number determining step for determining the number of slots necessary for data transmission based on data information including a data rate sent from another wireless communication device;
A priority slot acquisition step of acquiring the priority slots to be preferentially transmitted by the wireless communication device based on the communication status by the number of slots determined by the slot number determination procedure;
And a priority slot allocation step of allocating the priority slot to the other wireless communication device. A receiving step of receiving priority slot data including assigning a priority slot to which the first wireless communication device should preferentially transmit data to the second wireless communication device;
An assignment destination determination step of determining whether or not the wireless communication device corresponds to the second wireless communication device;
A data generation step for generating transmission data;
A transmission timing control step for controlling the timing of transmitting the transmission data based on the timing of the priority slot;
A transmission step of transmitting the transmission data based on the control of the transmission timing control means when it is detected that the priority slot is allocated and the wireless communication device is determined to correspond to the second wireless communication device; A program characterized by being executed.

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