JP2017079339A - Communication control device, radio terminal, memory card, integrated circuit, and radio communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication control system capable of increasing throughput by making acknowledgments to a plurality of terminals highly efficient.SOLUTION: A radio communication control device 11 is a communication control device for controlling communication with a plurality of object communication devices 1A-4A, used in radio communication devices including a radio communication unit, and comprises a control unit. The control unit comprises a control unit that receives a frame transmitted by spatial multiplexing from each of the plurality of object communication devices via the radio communication unit, and transmits an acknowledgment frame including an inspection result of whether reception of each of the frames transmitted by the plurality of object communication devices is a success or not to the plurality of object communication devices 1A-4A via the radio communication unit.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a communication control device, a wireless terminal, a memory card, an integrated circuit, and a wireless communication method.

  IEEE802.11 standard wireless LAN (Local Area Network) adopting CSMA / CA (Carrier Sense Multiple Access / Collision Avoidance) is widely known as a wireless communication system that performs communication between wireless access points and wireless terminals. . In the IEEE802.11ac standard, downlink multi-user MIMO (DL-MU-MIMO) technology, which is an extension of MIMO (Multi-Input Multi-Output) technology, is employed. In downlink multi-user MIMO, the access point uses a technique called beam forming, which enables data transmission by spatially orthogonal beams to each wireless terminal, so for multiple wireless terminals, Different data can be sent at the same time. As a result, the system throughput can be improved.

  In addition, the Study Group (SG) called IEEE802.11 HEW (High Efficiency WLAN), which considers the successor to the IEEE802.11ac standard, aiming for higher efficiency, was approved in May 2013 and improved in efficiency. Technology aimed at achieving this is being studied. One of the candidate technologies is uplink multi-user MIMO (UL-MU-MIMO) technology. In uplink multiuser MIMO, a plurality of terminals perform data transmission to an access point using beams that are spatially orthogonal at the same timing, thereby improving the efficiency of uplink transmission.

  When uplink multi-user MIMO technology is employed, the access point receives data from multiple terminals simultaneously. Therefore, the access point notifies each terminal that has transmitted data whether or not it has been received without error (delivery confirmation response), and makes a retransmission request to the terminal that has transmitted the data that could not be received correctly. Automatic Repeat reQuest) is required.

  In uplink multi-user MIMO, it is necessary to send a delivery confirmation response to a plurality of terminals that have received data at the same time. Therefore, it is inefficient to send a delivery confirmation response to each terminal sequentially. For this reason, a mechanism for efficiently returning delivery confirmation responses to a plurality of terminals is desired.

  For example, although it is not premised on uplink multi-user MIMO, aggregate acknowledgment acknowledgment (ACK) frames to multiple terminals are aggregated as a single superframe for data sequentially transmitted from multiple terminals. (Aggregate) and reply methods are known. By using this method, time such as a frame interval can be omitted as compared with the case of sequentially returning ACK frames to each terminal. Therefore, it is possible to improve the efficiency of ACK responses to a plurality of terminals.

  However, since this method only aggregates a plurality of conventional ACK frames, the superframe format still has an overhead part such as the presence of duplicate information fields for each terminal. This hinders high efficiency and high throughput.

Patent No. 4047836

  An embodiment of the present invention aims to increase the throughput by increasing the efficiency of delivery confirmation responses to a plurality of terminals.

  A wireless communication control device as an embodiment of the present invention is a communication control device that controls communication with a plurality of target communication devices, which is used in a wireless communication device having a wireless communication unit, and includes a control unit.

  The control unit receives a frame transmitted by spatial multiplexing from each of the plurality of target communication devices via the wireless communication unit.

  The control unit transmits a delivery confirmation response frame including a check result indicating whether or not the reception of the frames transmitted from the plurality of target communication devices has been successful, via the wireless communication unit, to the plurality of target communication devices. Send to.

1 is a diagram showing a wireless communication system according to a first embodiment. The figure explaining the outline | summary of an uplink multiuser MIMO transmission start. The figure which shows the example of a frame format of an uplink multiuser MIMO trigger frame. FIG. 5 is a diagram showing an example of a frame format of a delivery confirmation response frame according to the first embodiment. The functional block diagram of the radio | wireless communication apparatus mounted in an access point. The functional block diagram of the radio | wireless communication apparatus mounted in a radio | wireless terminal. FIG. 10 is a diagram showing an example of a frame format of a delivery confirmation response frame according to the second embodiment. FIG. 9 is a diagram illustrating an example of a hardware configuration of a wireless communication device mounted on an access point according to a third embodiment. FIG. 10 is a diagram illustrating an example of a hardware configuration of a wireless communication device mounted on a wireless terminal according to a third embodiment. FIG. 10 is a perspective view of a wireless device according to a fourth embodiment. The figure which shows the memory card based on 4th Embodiment. The figure which shows an example of the frame exchange of a contention period.

  Hereinafter, the present embodiment will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 shows a wireless communication system according to the first embodiment.

  The wireless communication system in FIG. 1 is a wireless network including an access point (AP) 11 and a plurality of wireless terminals (stations) 1, 2, 3, and 4. The access point 11 is also a form of a wireless terminal. The access point 11 and each of the wireless terminals 1 to 4 perform wireless communication according to an arbitrary wireless communication method. As an example, the access point 11 and each of the wireless terminals 1 to 4 perform wireless communication according to the IEEE802.11 standard. In the following description, a description will be given mainly assuming a wireless LAN of the IEEE802.11 standard, but the present embodiment is not limited to this.

  The access point 11 includes a plurality of antennas. In the example of FIG. 1, the access point 11 includes four antennas 12A, 12B, 12C, and 12D. The access point 11 is equipped with a wireless communication device (see FIG. 5 described later). The wireless communication device includes a wireless communication unit and a communication control device that controls communication with a plurality of wireless terminals 1 to 4 that are a plurality of target communication devices.

  Each of the wireless terminals 1 to 4 includes one or more antennas. In the example of FIG. 1, each of the wireless terminals 1 to 4 includes one antenna 1A, 2A, 3A, and 4A. Each wireless terminal is equipped with a wireless communication device (see FIG. 6 described later). The wireless communication device includes a wireless communication unit and a communication control device that controls communication with the access point 11 that is the target communication device.

  The access point 11 forms a wireless network (referred to as a first network) with each wireless terminal. Alternatively, the access point 11 may be connected to another wired or wireless network (referred to as a second network). The access point 11 relays communication between the first network and the second network and between wireless terminals. The data frame generated in each of the wireless terminals 1 to 4 is transmitted to the access point 11 by wireless communication, and the access point 11 transmits the data frame to another wireless terminal of the first network or the second network as necessary. .

  When data frames generated by the wireless terminals 1 to 4 are transmitted to the access point 11, transmission is performed by spatial multiplexing. Spatial multiplexing transmission means that a plurality of data streams are simultaneously transmitted in the same frequency band. Specifically, among the wireless terminals 1 to 4, a plurality of wireless terminals simultaneously transmit data frames addressed to the access point 11 through uplink multiuser MIMO. Through uplink multi-user MIMO transmission, a plurality of terminals can simultaneously transmit data frames, thereby improving throughput.

  After receiving data frames from a plurality of terminals by uplink multiuser MIMO transmission, the access point 11 checks the CRC (cyclic redundancy code) of each received data frame. Thereby, it is checked whether or not the data frame has been correctly received from each terminal without error. The access point 11 transmits a delivery confirmation response frame including the result of the inspection for each terminal. Each terminal confirms whether or not the data frame transmitted by the own device has been correctly received by the access point by confirming the test result of the own device in the delivery confirmation response frame. If the inspection result indicates failure, each terminal retransmits the data frame as necessary. Details of the delivery confirmation response method will be described later.

  In the example of FIG. 1, the number of data streams that can be simultaneously transmitted to the access point 11 is four, and the number of wireless terminals that communicate simultaneously is four. However, the present embodiment is not limited to this. For example, the number of data streams that can be transmitted to the access point 11 may be four, and the number of wireless terminals that communicate simultaneously may be three. In this case, one of the three wireless terminals may include a plurality of antennas, and the wireless terminal may perform two-stream MIMO transmission to the access point 11. In FIG. 1, in addition to the wireless terminals 1 to 4, there may be other terminals that have established a wireless link with the access point 11.

  In uplink multiuser MIMO transmission, the number of data streams that can be simultaneously transmitted to the access point 11 is limited depending on the number of antennas provided in the access point 11. For this reason, each wireless terminal needs to know in advance whether or not its own terminal may transmit. In addition, each wireless terminal that performs data frame transmission needs to match the transmission timing by some method.

  Therefore, in the uplink multiuser MIMO, as shown in the example of FIG. 2, the access point 11 previously notifies the wireless terminal that belongs to the first network of the wireless terminal that permits the uplink multiuser MIMO transmission ( Hereinafter, permitted terminal information) is transmitted. In addition, the access point 11 transmits a notification frame serving as a trigger for adjusting the transmission timing for each notified wireless terminal to perform uplink multiuser MIMO transmission. In the present embodiment, the permitted terminal information for uplink multiuser MIMO transmission is also included in the notification frame serving as the trigger. However, a frame including permitted terminal information for uplink multiuser MIMO transmission may be transmitted separately from the notification frame serving as a trigger.

  Specifically, in order to implement uplink multiuser MIMO transmission, the access point 11 first selects a plurality of wireless terminals that permit uplink multiuser MIMO transmission. Any method of selecting a wireless terminal may be used. For example, a method of selecting from wireless terminals for which a transmission request has been made in advance, or a method of sequentially selecting from round-robin from wireless terminals that have established a wireless link, can be considered. However, the number of wireless terminals selected at a time is equal to or less than the number of antennas provided in the access point 11 itself.

  In order to permit uplink multiuser MIMO transmission to the selected wireless terminal, the access point 11 transmits a notification frame including permitted terminal information specifying a plurality of selected wireless terminals from any one antenna. Note that the access point 11 can also transmit the notification frame from a plurality of antennas. The notification frame is transmitted by broadcast as an example. However, the notification frame may be transmitted by a method other than broadcast, such as multicast or unicast that includes a permitted wireless terminal.

  Note that, based on CSMA / CA, the access point 11 performs carrier sense before transmission of the notification frame and acquires a transmission right. As for the transmission right, if a signal of a certain level or higher is not received during carrier sense, the carrier sense result is acquired as idle. If a signal of a certain level or higher is received during carrier sense, the carrier sense result is busy and no transmission right is acquired. In this case, carrier sense may be performed again with a back-off time.

  In the example of FIG. 2, the wireless terminals 1 to 4 are selected as the wireless terminals. Each of the wireless terminals 1 to 4 receives the notification frame transmitted from the access point 11. The wireless terminals 1 to 4 recognize the fact that their own device is designated as the target of uplink multiuser MIMO transmission by analyzing the permitted terminal information (notification information) in the notification frame.

  Each of the wireless terminals 1 to 4 designated as the uplink multi-user MIMO transmission target transmits the data frame held in its transmission buffer to the access point 11 in the same frequency band after a certain time T1 from the reception of the notification frame. Send. That is, a data frame is transmitted from each wireless terminal by spatially multiplexed uplink multiuser MIMO. The fixed time T1 may be an arbitrary value as long as it is a predetermined fixed time. As an example, SIFS (Short Inter-frame Space) time (= 16 μs), which is a time interval between frames defined in the MAC protocol specification of IEEE802.11 wireless LAN, can be used.

  In addition, each of the wireless terminals 1 to 4 designated as the uplink multi-user MIMO transmission target is not a method of transmitting a data frame after a certain time T1 from reception of the notification frame, but describes the timing to be transmitted in the notification frame, A method may be used in which each wireless terminal grasps the transmission timing by receiving a notification frame and transmits a data frame held in its transmission buffer at a designated timing. In the case of this method, the transmission timing to be notified in the notification frame may be notified as an elapsed time after receiving the notification frame, or may be notified of the value of the time stamp time shared with each other.

  Regardless of the method, the wireless terminals 1 to 4 can match the transmission timing, and the data frame can be transmitted at the same timing. That is, uplink multi-user MIMO transmission is possible.

  In addition, the data frame of each wireless terminal transmitted by the uplink multiuser MIMO is received as a signal superimposed at the access point 11 at the same time. For this reason, the access point 11 needs to spatially separate these signals. Specifically, the access point 11 estimates the uplink radio channel response from each radio terminal to the access point 11 by using the preamble part added to the head of the data frame transmitted by each radio terminal. To do. The preamble part is composed of a known bit string used for radio channel estimation. The access point 11 can correctly spatially separate fields (for example, data fields) after the preamble of the data frame received from each wireless terminal by using the estimated uplink channel response. This can be performed using a known method such as a ZF (Zero-Forcing) method, an MMSE (Minimum Mean Square Error) method, or a maximum likelihood estimation method.

  Here, when the access point 11 estimates each radio channel response using the preamble portion of the data frame transmitted from each wireless terminal, at least the preamble portions are orthogonal to each other (except in space) between the wireless terminals. It must be sent in the form. If the preamble parts are not orthogonal, the access point 11 will receive the preamble part mixed by each wireless terminal, and the radio propagation path cannot be estimated correctly. In this case, the field after the preamble part cannot be spatially separated (orthogonalized). Since the preamble parts are orthogonal, the access point 11 can correctly recognize the preamble part of each wireless terminal. By utilizing this, the access point 11 can perform radio channel estimation between each radio terminal and the access point 11, respectively.

  As a method of orthogonalizing the preamble part of the data frame transmitted by each wireless terminal, orthogonalization may be performed by any of temporal, frequency, and code methods. In the case of time orthogonality, each wireless terminal sequentially transmits the preamble part, so that only one wireless terminal transmits the preamble part at a certain time. In the case of frequency orthogonality, each wireless terminal transmits a preamble part using a different frequency. In the case of code orthogonality, each wireless terminal transmits a preamble portion with a coding pattern using different rows (or different columns) of the orthogonal matrix. Each row (or each column) of the orthogonal matrix is orthogonal to each other. In any of the orthogonalization methods, the access point 11 can identify the preamble part of each wireless terminal. It is assumed that the system determines in advance which method of orthogonalizing the preamble part.

  Also, in order to make the preamble parts transmitted from each wireless terminal orthogonal to each other, it is necessary to give information on how to transmit to each wireless terminal. Specifically, in the case of time orthogonality, Each preamble part is transmitted at different time timings, or in which frequency each orthogonal part is transmitted in the case of frequency orthogonality, and in which case different coding patterns (in which row or column of the orthogonal matrix) Information on whether to transmit the preamble part in each pattern) is required. For example, in the case of frequency orthogonality, if two or more wireless terminals transmit the preamble part at the same frequency, they are not orthogonal, so the access point 11 is wireless with the wireless terminal that transmitted them. This is because the propagation path cannot be estimated correctly. This information may be notified to each wireless terminal that the access point 11 permits uplink multiuser MIMO transmission using a notification frame. Or you may give this information to each radio | wireless terminal by notifying by the method different from this.

  In any case, when each wireless terminal performs data transmission using uplink multiuser MIMO, it is assumed that the preamble part to be transmitted by each wireless terminal or the transmission method of the preamble part can be grasped by some method. Each wireless terminal can transmit data in which the preamble parts are orthogonal to each other by transmitting the method by grasping the grasped preamble part in advance.

  FIG. 3 shows an example of the frame format of the notification frame. For example, it includes a Frame Control field, Duration field, RA field, TA field, common information field, terminal information field, and FCS field.

  Information indicating a frame type or the like is set in the Frame Control field.

  In the Duration field, a time set as virtual carrier sense is stored. A device that has received a frame whose value is set in the Duration field counts down until the time set in this field becomes 0, and recognizes that it is busy until 0. This is called virtual carrier sense.

  In the RA (Receiver Address) field, a MAC address of a frame destination (transmission destination) is usually set. Since the notification frame is transmitted to a plurality of wireless terminals, a broadcast address may be set in the RA field. However, as the RA, a multicast address including a permitted wireless terminal may be set instead of a broadcast address, or a MAC address (unicast address) of the wireless terminal may be set. When setting a unicast address, a plurality of destinations may be specified by providing a plurality of RA fields. In this case, it may be defined in the Frame Control field that a plurality of destinations are set.

  The TA (Transmitter Address) field contains the MAC address of the frame transmission source. In the case of a notification frame, the MAC address of the access point is set in the TA field.

  In the common information field, information to be notified in common to each wireless terminal that permits uplink multiuser MIMO transmission is set as information necessary for performing uplink multiuser MIMO transmission. For example, in the case of a method of designating transmission timing with a notification frame for each wireless terminal performing uplink multi-user MIMO transmission, transmission timing is set in the common information field. In the method of performing data transmission after a certain time T1 from the reception of the notification frame, since the value of T1 is known by each wireless terminal, notification of transmission timing is unnecessary. As will be described later, since the number of terminal information fields is variable, the number of terminal information fields may be set in the common information field. In addition, the data frame length permitted in uplink multiuser MIMO transmission may be set in the common information field.

  The terminal information field (individual information field) is provided for each wireless terminal that permits uplink multiuser MIMO transmission. The number of terminal information fields is variable depending on the number of wireless terminals that allow uplink multiuser MIMO. In the example of FIG. 2, four terminal information fields are provided. That is, a terminal information field 1, a terminal information field 2, a terminal information field 3, and a terminal information field 4 are provided.

  In the terminal information field, identification information of a wireless terminal that is an uplink multiuser MIMO transmission target, and information necessary for each designated wireless terminal to perform uplink multiuser MIMO transmission, Information (such as a preamble transmission method as described later) is included. As a modification, it is also conceivable to set identification information of each wireless terminal that is an uplink multi-user MIMO transmission target in a common information field instead of each terminal information field.

  Each wireless terminal receives a notification frame having a format as shown in FIG. 3, and if its own identification information is included in any of the terminal information fields (or common information field), it It can be grasped that it is specified as a target for multi-user MIMO transmission. In the example of FIG. 2, identification information of the wireless terminals 1 to 4 is set in the terminal information fields 1 to 4, respectively.

  Further, when each wireless terminal notifies the transmission method of the preamble part when performing data transmission by uplink multi-user MIMO using a notification frame, the preamble part to be performed by each wireless terminal in each terminal information field Transmission methods (time timing, frequency, or orthogonal matrix code pattern) are set. Each wireless terminal transmits a data frame according to a preamble part transmission method specified in the terminal information field including the identification information of the own device. Thereby, the preamble part of the data frame transmitted by each wireless terminal is transmitted in an orthogonal form.

  In addition to the method of setting the identification information of the wireless terminal that is the uplink multi-user MIMO transmission target in each terminal information field as a method of specifying the wireless terminal that is the uplink multi-user MIMO transmission target, the following groups A method of notifying the number may be used.

  The access point 11 performs grouping of combinations of various terminals that perform uplink multiuser MIMO transmission in advance from a plurality of wireless terminals that have established wireless links. For example, group 1 is a combination of wireless terminals 1, 2, 3, and 4, group 2 is a combination of wireless terminals 1, 3, and 4, group 3 is wireless terminals 1, 2, 4, 5, and the like. There may be any number of types of groups, and one wireless terminal may belong to a plurality of groups.

  The access point 11 notifies each wireless terminal of the grouping result using a dedicated frame, so that each wireless terminal can grasp in advance which group number the device belongs to. The access point 11 may add a new group as appropriate, or may change the combination of wireless terminals belonging to an already existing group. The access point 11 notifies each time a group is added or changed using a dedicated frame.

  At this time, the transmission method of the preamble part of each grouped wireless terminal may be notified. In this case, the radio terminal belonging to the same group is notified of the preamble part transmission method for transmitting the preamble part orthogonally to each other.

  Each wireless terminal knows in advance which group number it belongs to and what preamble part it should send for each group number to which it belongs. Yes. For this reason, the access point 11 can designate a terminal that permits uplink multiuser MIMO transmission only by notifying the group number in accordance with the combination of terminals that want to permit uplink multiuser MIMO in the notification frame. When notifying the group number in the notification frame, for example, the group number is set in the common information field.

  Each wireless terminal receives the notification frame, and when the group number set in the common information field is a group number to which the own apparatus belongs, the own apparatus is a target terminal for uplink multiuser MIMO transmission. Recognize that.

  In the case of this method, notification using the identification information of the wireless terminal in the notification frame is unnecessary each time.

  In the FCS (Frame Check Sequence) field, FCS information of the notification frame 51 is set. The FCS information is used for frame error detection on the receiving device side.

  Next, a method of a delivery confirmation response to each wireless terminal will be described for the data frame transmitted from each wireless terminal by uplink multiuser MIMO transmission.

  After receiving data frames from multiple terminals by uplink multiuser MIMO transmission, the access point 11 performs error detection (CRC check) using the FCS field of each received data frame. The access point 11 creates a transmission acknowledgment frame that includes the error detection result in each received data frame in the form of a bitmap. In the bitmap, each bit corresponds to the CRC result of one data frame. As shown in FIG. 2, the access point 11 transmits the delivery confirmation response frame after a predetermined time T2 from the reception of each received data frame.

  The transmission of the delivery confirmation response frame by the access point 11 is performed by broadcast as an example. However, the notification frame may be transmitted by a method other than broadcast, such as multicast or unicast including a permitted wireless terminal.

  The fixed time T2 may be an arbitrary value as long as it is a predetermined fixed time. As an example, SIFS (Short Inter-frame Space) time (= 16 μs), which is a time interval between frames defined in the MAC protocol specification of IEEE802.11 wireless LAN, can be used.

  In addition, the transmission timing of the delivery confirmation response frame transmitted by the access point 11 may be after an arbitrary time instead of after a predetermined time T2. In this case, for example, the transmission timing is notified in advance to each wireless terminal by a notification frame or another frame. Thereby, each wireless terminal can grasp the timing of receiving the delivery confirmation response frame.

  Further, the access point 11 may perform carrier sense before transmission of the delivery confirmation response frame based on CSMA / CA, and may transmit the delivery confirmation response frame after acquiring the transmission right.

  FIG. 4 shows an example of the frame format of the delivery confirmation response frame. This frame format includes, for example, a Frame Control field, Duration field, RA field, TA field, Bitmap field, and FCS field.

  When a delivery confirmation response frame is broadcast to a plurality of wireless terminals, a broadcast address is set in the RA field. However, when performing multicast transmission, a multicast address may be set in the RA field instead of a broadcast address. Alternatively, the MAC address (unicast address) of one wireless terminal among a plurality of wireless terminals may be set. In this case, the wireless terminal stores information of other designated wireless terminals other than the own device in the notification frame, and the address of the designated other wireless terminal is not the own device in this RA field. If stored, this delivery confirmation response frame may be interpreted as being addressed to the own device.

  Since the Frame Control field, Duration field, TA field, and FCS field are the same as the notification frame, description thereof is omitted.

  Details of the Bitmap field will be described below. The Bitmap field is set based on the CRC result of each data frame received from each wireless terminal by the uplink multiuser MIMO. Specifically, one bit of the bitmap represents the CRC result of one received data frame. Each bit is represented by “1” when CRC = OK (successful reception) and “0” when CRC = NG (reception failure). “1” and “0” may be reversed. Therefore, the minimum bit size required for the Bitmap field is the number of wireless terminals that transmit data by uplink multiuser MIMO transmission. In the case of FIG. 2, since data is transmitted by uplink multi-user MIMO transmission from four wireless terminals, the number of bits required for the Bitmap field is at least 4 bits. However, when one wireless terminal transmits a plurality of data streams and a different data frame is transmitted in each data stream, a bit is required for each data stream. In this case, the number of bits required for the Bitmap field is equal to or greater than the total number of data streams of the wireless terminals that perform uplink multiuser MIMO transmission. Hereinafter, the description will be continued assuming that one data frame is transmitted simultaneously from one wireless terminal.

  The length of the Bitmap field may be variable or fixed depending on the number of uplink multiuser MIMO multiplexes. In the fixed case, for example, the length of the Bitmap field is set to the same number of bits as the maximum number of wireless terminals (number of data frames) that can be transmitted by uplink multiuser MIMO transmission. In this case, the number of bits equal to (the maximum number of wireless terminals that can be transmitted−the number of transmitted terminals) is treated as reserved bits in the Bitmap field.

  In addition, the length of the Bitmap field may be determined by rounding up in units of 8 bits according to the minimum number of bits so that the length of the Bitmap field is in bytes. For example, in the case of FIG. 2, since the minimum number of bits required is 4 bits, it is rounded up in units of bytes, and the length of the Bitmap field is 8 bits. In this case, the number of bits added when rounding up in bytes (4 bits in the case of FIG. 2) is treated as reserved bits.

  Even if the length of the Bitmap field is variable or rounded up in units of 8 bits, the number of wireless terminals permitted for uplink transmission can be grasped in the notification frame transmitted in advance. Can figure out the length of the Bitmap field. Although not shown in FIG. 4, a field indicating the bitmap size may be added before the bitmap field as necessary.

  As described above, the Bitmap field in the delivery confirmation response frame reflects the CRC result of the data frame of each wireless terminal received by the uplink multiuser MIMO transmission.

  Next, a description will be given of which wireless terminal transmits data reflected in which bit position of the Bitmap field.

  Basically, the bit position is related to terminal information set in the terminal information field to be notified in the notification frame. For example, when allowing uplink multi-user MIMO transmission to four wireless terminals (terminals 1 to 4), terminal information field 1, terminal information field 2, terminal information field 3, and terminal information field 4 are provided as terminal information fields. It has been. When wireless terminal 1, wireless terminal 2, wireless terminal 3, and wireless terminal 4 are set in order as the wireless terminal identification information in each terminal information field, the Bitmap field in the delivery confirmation response frame also corresponds to that. The CRC result of the data frame transmitted by the wireless terminal 1, the CRC result of the data frame transmitted by the wireless terminal 2, the CRC result of the data frame transmitted by the wireless terminal 3, and the wireless terminal 4 transmitted in order from the least significant bit of the Bitmap The form reflects the CRC result of the data frame. For example, when the CRC results of the data frames transmitted by the wireless terminals 1 to 4 are OK, NG, NG, and OK, respectively, the Bitmap field is “1”, “0”, “0”, Expressed as “1”.

  When the wireless terminal 3, wireless terminal 2, wireless terminal 4, and wireless terminal 1 are set in order as the wireless terminal identification information in each terminal information field, the Bitmap field in the delivery confirmation response frame is the Bitmap field. In order from the least significant bit, the CRC results of the data frames transmitted by the wireless terminal 3, the wireless terminal 2, the wireless terminal 4, and the wireless terminal 1 are reflected.

  Here, an example in which the CRC result is reflected in order from the least significant bit is shown, but a form in which the CRC result is reflected in order from the most significant bit may be employed. Also, instead of reflecting the CRC result in order from the least significant bit or the most significant bit, the CRC result may be reflected in order from the predetermined bit other than the least significant bit or the most significant bit in the direction of the lower bit or the upper bit. Absent. In this case, assuming that the most significant bit and the least significant bit are continuous, the wireless terminal may specify its own bit. In addition to the method described here, any method can be used as long as the correspondence between the order in which the identification information of the wireless terminal is set in each terminal information field and the bit position of the Bitmap field is uniquely determined.

  As described above, each wireless terminal receives the notification frame, thereby grasping that its own apparatus is a wireless terminal that is an uplink multiuser MIMO transmission target, and notifies itself in which terminal information field. Know what was done. Thereby, each wireless terminal can grasp which bit position of Bitmap corresponds to the information reflecting the CRC result for the data frame transmitted by the own device in the acknowledgment response frame for data frame transmission.

  In the example described above, the position of the CRC result of each wireless terminal is specified in the Bitmap field according to the order in which the identification information of each wireless terminal is set in each terminal information field. Can be specified in the common information field or each terminal information field. For example, the wireless terminal 1 can be designated as the least significant bit, the wireless terminal 2 can be designated as the third bit from the least significant bit, and the like. In this case, the bit position of each wireless terminal in the Bitmap field and the order of the identification information of the wireless terminal set in each terminal information field are not necessarily related.

  As a method of specifying the wireless terminal that is the target of uplink multi-user MIMO transmission, instead of setting individual identification information in the terminal information field, when notifying the group number by prior grouping, do the following: Thus, each wireless terminal identifies the bit position of its own device.

  As an example, the bit position in the Bitmap is caused by the order of notification in the dedicated frame when the grouping result is notified to each wireless terminal using the dedicated frame. For example, it is assumed that group number 1 is notified in a dedicated frame as wireless terminals 1, 2, and 3 and group number 2 is wireless terminals 2, 3, and 4. In this case, in the case of group number 1, wireless terminals 1, 2, and 3 are assigned in this order from the least significant bit in the Bitmap. In the case of group number 2, wireless terminals 2, 3, and 4 are assigned in this order from the least significant bit in the Bitmap. As described above, even when the group number is notified in the notification frame, the bit position in the Bitmap field of the delivery confirmation response frame is uniquely determined. Here, an example of assigning in order from the least significant bit is shown, but as described above, assignment may be made in order from the most significant bit or from other bits.

  FIG. 5 is a functional block diagram of the wireless communication device of the access point 11. As described above, the access point 11 may be connected to a network (second network) other than the network (first network) on the wireless terminal side. FIG. 5 shows the configuration of the wireless communication device on the first network side.

  The wireless communication apparatus includes a control unit 101, a transmission unit 102, a reception unit 103, antennas 12A, 12B, 12C, and 12D, and a buffer 104. The control unit 101 corresponds to a communication control device that controls communication with a wireless terminal, and the transmission unit 102 and the reception unit 103 form a wireless communication unit as an example. The processing of the control unit 101 or the communication control device may be performed by software (program) that operates on a processor such as a CPU, may be performed by hardware, or may be performed by both software and hardware. It may be broken.

  The buffer 104 is a storage unit for transferring data frames between the upper layer and the control unit 101. The upper layer stores the frame received from the second network in the buffer 104 for relay to the first network, and receives the frame received from the first network from the control unit 101. The upper layer may perform communication processing above the MAC layer such as TCP / IP and UDP / IP. Further, the upper layer may perform processing of an application layer that processes data. The upper layer operation may be performed by software (program) processing by a processor such as a CPU, may be performed by hardware, or may be performed by both software and hardware.

  The control unit 101 mainly performs part of the MAC layer processing and physical layer processing (for example, MIMO-related processing). The control unit 101 controls communication with each wireless terminal in the first network by transmitting and receiving frames via the transmission unit 102 and the reception unit 103. Further, the control unit 101 may perform control so as to periodically transmit a beacon signal frame. The control unit 101 may include a clock generation unit that generates a clock. The control unit 101 may be configured to receive a clock from the outside. The control unit 101 may manage the internal time based on a clock generated by the clock generation unit or an externally input clock. The control unit 101 may output the clock generated by the clock generation unit to the outside.

  Upon receiving an association request from a wireless terminal, the control unit 101 establishes a wireless link with the wireless terminal through a process such as authentication as necessary. The control unit 101 periodically checks the buffer 104. Alternatively, the control unit 101 confirms the buffer 104 by an external trigger such as the buffer 104. The control unit 101 selects a plurality of wireless communication terminals that allow uplink multiuser MIMO transmission from wireless terminals that have established a wireless link based on some determination, and terminal permission information (notification information) that specifies these wireless terminals. A notification frame including is generated. In addition, the control unit 101 uses information (common information, individual information, or both) for designating a data frame transmission method to each wireless terminal, if necessary, a common information field of the notification frame, terminal information Set to field or both.

  The control unit 101 transmits the generated notification frame from the transmission unit 102 according to the communication method to be used. As an example, when carrier sense is performed and a transmission right can be acquired, the control unit 101 outputs the generated notification frame to the transmission unit 102. The transmission unit 102 includes a transmission system corresponding to each antenna, and performs a desired physical layer process such as a modulation process or addition of a physical header to the input notification frame using a specific transmission system. Further, DA conversion, filter processing for extracting a signal component in a desired band, and frequency conversion (up-conversion) are performed on the frame after processing in the physical layer. Transmitter 102 amplifies the frequency-converted signal and radiates it as a radio wave from any one antenna to the space. A configuration in which a notification frame is input to a plurality of transmission systems and transmitted from a plurality of antennas is also possible.

  The signal received by each antenna is processed in the receiving unit 103 for each reception system corresponding to the antenna. For example, after transmitting the notification frame described above, signals of data frames returned from a plurality of wireless terminals specified by the notification frame are received simultaneously by each antenna (uplink multiuser MIMO reception). The reception signal of each antenna is input to each reception system in the reception unit 103. Each received signal is amplified in the receiving system, frequency-converted (down-converted), and a desired band component is extracted by filtering processing. Each extracted signal is further converted into a digital signal by AD conversion, subjected to physical layer processing such as demodulation, and then input to the control unit 101.

  The control unit 101 obtains an uplink channel response matrix by performing channel estimation based on a preamble of a signal input from each reception system. Based on the uplink propagation path response matrix obtained by the estimation, the control unit 101 separates the data part after the preamble for each wireless terminal (for each propagation path information frame). As a result, the access point 11 can receive data frames transmitted simultaneously from a plurality of wireless terminals without interference.

  In addition, the control unit 101 performs control so that a delivery confirmation response frame is transmitted after a predetermined time from the reception of the data frame transmitted from each wireless terminal by the uplink multiuser MIMO. The control unit 101 performs a CRC check on the data frame received from each wireless terminal, reflects each CRC result in the Bitmap format, and generates a delivery confirmation response frame including the Bitmap. As an example, in Bitmap, to which bit position the CRC result of the received data frame from each wireless terminal is reflected is determined in a one-to-one relationship with the order of specifying the wireless terminal in the notification frame. The specific method is as described above.

  The transmission unit 102 inputs a delivery confirmation response frame to at least any one of a plurality of transmission systems. The transmission system modulates the input acknowledgment frame, performs physical layer processing such as adding a physical header to the modulated signal, and DA-converts each frame after physical layer processing. In addition, filter processing for extracting a signal component in a desired band and frequency conversion (up-conversion) are performed. Transmitter 102 amplifies the frequency-converted signal and radiates it as a radio wave from the antenna corresponding to the transmission system. In addition, the structure which inputs a delivery confirmation response frame into a some transmission system, and transmits from a some antenna is also possible.

  The above-described separation of the processes of the control unit 101 and the transmission unit 102 is an example, and other forms are possible. For example, processing up to the digital area may be performed by the control unit 101, and processing after DA conversion may be performed by the transmission unit 102. Similarly for the separation of the processing of the control unit 101 and the receiving unit 103, the processing up to AD conversion is performed by the receiving unit 103, and the processing of the digital area including the processing of the physical layer thereafter is performed by the control unit 101. Good. Carvings other than those described here may be performed.

  FIG. 6 is a functional block diagram of a wireless communication device mounted on the wireless terminal 1. Since the wireless communication devices mounted on the wireless terminals 2 to 4 have the same configuration as the wireless terminal 1, the description of the wireless terminal 1 will be replaced with the description of the wireless terminals 2 to 4 below.

  The wireless communication apparatus includes a control unit 201, a transmission unit 202, a reception unit 203, an antenna 1A, and a buffer 204. The control unit 201 corresponds to a communication control device that controls communication with the access point 11, and the transmission unit 202 and the reception unit 203 form a wireless communication unit as an example. The processing of the control unit 201 or the communication control device may be performed by software (program) that operates on a processor such as a CPU, may be performed by hardware, or may be performed by both software and hardware. It may be broken.

  The buffer 204 is a storage unit for transferring data frames between the upper layer and the control unit 201. The upper layer generates a frame to be transmitted to another wireless terminal, the access point 11, or a device on another network such as a server, and stores the frame in the buffer 204 or receives the frame received by the first network in the buffer 201. Or receive through. The upper layer may perform communication processing above the MAC layer such as TCP / IP and UDP / IP. Further, the upper layer may perform processing of an application layer that processes data. The upper layer processing may be performed by software (program) that operates on a processor such as a CPU, may be performed by hardware, or may be performed by both of the software and hardware.

  The control unit 201 mainly performs MAC layer processing. The control unit 201 controls communication with the access point 11 by transmitting and receiving frames to and from the access point 11 via the transmission unit 202 and the reception unit 203. For example, the control unit 201 receives a beacon signal frame periodically transmitted from the access point 11 via the antenna 1A and the reception unit 203. The control unit 201 may include a clock generation unit that generates a clock. The control unit 201 may be configured to receive a clock from the outside. The control unit 201 may manage the internal time based on a clock generated by the clock generation unit or an externally input clock. The control unit 201 may output the clock generated by the clock generation unit to the outside.

  For example, the control unit 201 receives a beacon signal, makes an association request to the access point 11, and establishes a wireless link with the access point 11 through a process such as authentication as necessary. The control unit 201 periodically checks the buffer 204. Alternatively, the control unit 201 confirms the buffer 204 by an external trigger such as the buffer 204. When the control unit 201 confirms that there is a frame to be transmitted to the access point 11, the control unit 201 reads the frame and transmits it through the transmission unit 202 and the antenna 1A according to the communication method to be used. Alternatively, by receiving the notification frame from the access point 11, the frame is read out at a timing when the own apparatus is permitted to transmit in the uplink multiuser MIMO, and the transmission unit 202 and the antenna 1A Send through.

  The transmission unit 202 performs desired physical layer processing such as modulation processing and addition of a physical header to the frame input from the control unit 201. Further, DA conversion, filter processing for extracting a signal component in a desired band, and frequency conversion (up-conversion) are performed on the frame after processing in the physical layer. Transmitter 202 amplifies the frequency-converted signal and radiates it as a radio wave from the antenna.

  The signal received by the antenna 1A is processed by the receiving unit 203. For example, a notification frame signal is received from the access point 11 and processed by the receiving unit 203. The reception signal is amplified by the reception unit 203, subjected to frequency conversion (down-conversion), and a desired band component is extracted by a filering process. Each extracted signal is further converted into a digital signal by AD conversion, subjected to physical layer processing such as demodulation, and then input to the control unit 201.

  When the control unit 201 detects a notification frame based on the input signal, the control unit 201 determines whether the own device is designated as an uplink multi-user MIMO transmission target in the notification frame, and whether the identification information of the own device is any terminal information Check if it is stored in the field. Further, the control unit 201 determines the CRC result of the data frame transmitted by the own device in the Bitmap field in the delivery confirmation response frame transmitted from the access point 11 according to the position (order) in which the identification information of the own device is included. Check the bit position where is reflected.

  Note that the control unit 201 can be configured to confirm whether its own device is designated as an object of uplink multiuser MIMO transmission based on whether the identification information of the own device is stored in the common information field. Also in this case, the bit position in which the CRC result of the own device is reflected is confirmed based on the position (order) in which the identification information of the own device is included in the common information field.

  In addition, it is possible to confirm whether or not the own apparatus is designated as an uplink multi-user MIMO transmission target using the group number designated in the common information field. In this case, a notification of the group number to which the own device belongs is received from the access point 11 in advance. When the group number to which the own device belongs is notified, the bit position in which the CRC result of the own device is reflected is confirmed based on the position (order) in which the identification information of the own device is designated in the group.

  When the control unit 201 confirms that its own device is designated as an uplink multiuser MIMO transmission target, the control unit 201, if necessary, information on the uplink multiuser MIMO transmission method of its own device (common information, It is confirmed whether (individual information) is stored in the common information field, the terminal information field, or both of these fields. If stored, information related to the transmission method is read from the corresponding field. When the read information includes information for specifying a preamble to be used when transmitting the data frame of the own apparatus, the preamble to be used is specified based on the information. If the preamble to be used is given in advance, the preamble may be used.

  When the control unit 201 confirms that its own device is designated as an uplink multi-user MIMO transmission target in the notification frame, the control unit 201 reads the data frame stored in the buffer 204 and uses the specified use preamble as necessary. Designate and control to transmit to the access point 11 after a certain time from the reception of the notification frame. The data frame is transmitted via the transmission unit 202 and the antenna 1A. The operation of the transmission unit 202 is as described above.

  In addition, when the timing of uplink multiuser MIMO transmission is specified in the notification frame, a configuration in which transmission is performed to the access point 11 at the specified timing is also possible.

  The control unit 201 waits for a delivery confirmation response frame transmitted from the access point 11 after transmitting the data frame by the uplink multiuser MIMO. When the control unit 201 detects reception of the delivery confirmation response frame from the access point 11 based on the signal input from the reception unit 203, the control unit 201 checks the Bitmap field in the delivery confirmation response frame. The control unit 201 specifies the bit position in the Bitmap field that reflects the CRC result for the data frame transmitted by the device itself. The control unit 201 determines whether or not the data frame has been correctly transmitted in the uplink multiuser MIMO depending on whether the bit is “0” or “1”.

  When the control unit 201 confirms that the data frame has been correctly transmitted by the uplink multiuser MIMO, the control unit 201 completes the transmission process. On the other hand, if it is confirmed that the data frame has not been transmitted correctly, the data frame is retransmitted as necessary. Any retransmission method can be used according to the system configuration. For example, when the device is specified in the notification frame next time, a method of transmitting a retransmission data frame by uplink multi-user MIMO, or an uplink of a retransmission data frame after SIFS elapses from completion of reception of an acknowledgment frame A method of transmitting by multi-user MIMO may be used. You may perform resending by methods other than these.

  Until now, the case where the frame transmitted by uplink multi-user MIMO is a data frame has been explained, but various management frames and control frames other than data frames can also be transmitted by uplink multi-user MIMO. It is. With regard to various management frames and control frames, these frames are stored in the buffer 204 as necessary, and the control unit 201 can transmit the frames by reading them from the buffer 204.

  The above-described separation of the processes of the control unit 201 and the transmission unit 202 is an example, and other forms are possible. For example, processing up to the digital domain may be performed by the control unit 201, and processing after DA conversion may be performed by the transmission unit 202. Similarly for the separation of the processing of the control unit 201 and the reception unit 203, the processing up to AD conversion is performed by the reception unit 203, and the processing of the digital area including the subsequent physical layer processing is performed by the control unit 201. Good. Carvings other than those described here may be performed.

  As described above, in the present embodiment, as a delivery confirmation response to each wireless terminal for uplink multiuser MIMO transmission, a delivery confirmation response to a plurality of wireless terminals is not sequentially returned, Reply in one delivery confirmation response frame. Thereby, overhead can be reduced and efficiency can be improved.

  Further, in the delivery confirmation response frame to be returned, the information of the delivery confirmation response for each wireless terminal is converted into a bitmap, so that a single delivery confirmation response frame for each wireless terminal is sent back as a super frame in a conventional manner. Compared with the case, the frame length can be shortened. For this reason, efficiency can be improved compared with the case of replying with one aggregated superframe.

  In this embodiment, the bit position of the delivery confirmation response to each wireless terminal in the Bitmap field is associated with the position (order) in which each wireless terminal is designated in the prior notification frame in a one-to-one correspondence. Thereby, each wireless terminal can identify the bit position where the CRC result of its own device is stored and grasp the CRC result only by receiving the delivery confirmation response frame and referring to the Bitmap field. Therefore, it is not necessary to add an information field including information on the bit position of each wireless terminal in the Bitmap field to the notification frame or the delivery confirmation response frame. Therefore, without adding such an information field, it is possible to efficiently realize a delivery confirmation response corresponding to uplink multi-user MIMO transmission using a combination of various wireless terminals.

(Second embodiment)
In the first embodiment, the frame transmission from each wireless terminal that has permitted uplink multiuser MIMO transmission in the notification frame is assumed to be only one single frame. In the second embodiment, frame transmission from each wireless terminal enables transmission of not only a single frame but also an aggregation frame (hereinafter referred to as a super frame) in which a plurality of frames are aggregated.

  The basic processing on the access point 11 side and each of the wireless terminals 1 to 4 is the same as that in the first embodiment. When each wireless terminal that has received the notification frame from the access point 11 confirms that its own device is allowed to perform uplink multi-user MIMO transmission within the notification frame, a plurality of data stored in a buffer in its own device A super frame in which frames are aggregated is transmitted at a predetermined transmission timing. Note that the frames aggregated into the superframe are not limited to data frames, and may be management frames or control frames, or a combination of these plural types of frames.

  A significant difference from the first embodiment is the frame format of a delivery confirmation response frame returned by the access point 11. FIG. 7 shows an example of the frame format of the delivery confirmation response frame in the second embodiment. As shown in FIG. 7, there are as many Bitmap fields as the number of wireless terminals to which the access point 11 permits uplink multiuser MIMO transmission in a notification frame. For example, in the case of FIG. 2, the number of Bitmap fields is 4.

  Each Bitmap field includes a CRC result of each data frame in the aggregated superframe transmitted by each wireless terminal. The arrangement order of each Bitmap field, that is, which wireless terminal's CRC result reflects each Bitmap field is related to the terminal information set in the terminal information field notified in the notification frame. That is, there is a one-to-one correspondence with the order of wireless terminals that are notified in the notification frame. That is, it can be considered that each Bitmap field of the delivery confirmation response frame in FIG. 7 corresponds to each bit of the Bitmap field of the delivery confirmation response frame in the first embodiment.

  Therefore, the number of Bitmap fields in the delivery confirmation response frame in the second embodiment is the maximum number of wireless terminals (or data streams) that can be transmitted by uplink multiuser MIMO, as in the first embodiment. May be. Alternatively, if the wireless terminal can transmit multiple data streams and can transmit a superframe separately for each stream, the number of Bitmap fields in the acknowledgment frame is the maximum number of streams that can be transmitted and received by the access point. May be.

  Since each Bitmap field in FIG. 7 includes the CRC result of each data frame in the superframe transmitted by each wireless terminal, the size of each Bitmap field is determined by the superframe when transmitting a superframe in uplink multiuser MIMO. The maximum number of data frames that can be aggregated in a frame. For example, when the maximum number of frames that can be aggregated is 8, the size of each Bitmap field is 8 bits. It is assumed that the maximum number of data frames that can be aggregated is predetermined. A configuration is also possible in which the maximum number of data frames that can be aggregated is different for each wireless terminal. In this case, the size of the Bitmap field may be different for each wireless terminal.

  In the delivery confirmation response frame in the second embodiment, in addition to the above, a field for setting a starting sequence number for each wireless terminal is prepared.

  The sequence number is data identification information added to each data frame, and an incremented number is added every time each wireless terminal transmits a data frame. Therefore, when each wireless terminal transmits a super frame using uplink multi-user MIMO, a plurality of sequence numbers are collected in the super frame.

  As an example, consider a case where a wireless terminal that is permitted to perform uplink multi-user MIMO transmission transmits a superframe in which data frames of sequence numbers = 3, 4, 5, and 6 are aggregated.

  The access point 11 receives the superframe, deaggregates (divides) the superframe, and then performs a CRC check on each divided data frame. As a result of the CRC check, the value of the smallest sequence number for which CRC = OK is set in the start sequence number field. For example, if the CRC results of sequence numbers = 3, 4, 5, and 6 are OK, NG, OK, and OK, respectively, “3” is set in the start sequence number field. On the other hand, when the CRC results of sequence numbers = 3, 4, 5, and 6 are NG, NG, OK, and OK, respectively, “5” is set in the start sequence number field.

  The access point 11 associates the set start sequence number with the start bit of the Bitmap field, and the subsequent bits reflect the CRC result of the sequence number incremented by 1. That is, the information corresponding to the bit position n of the Bitmap is the CRC result of the data frame corresponding to the sequence number of (start sequence number + n).

  For example, if the size of the Bitmap field is 8 bits and the CRC results for sequence numbers = 3, 4, 5, and 6 are OK, NG, OK, and OK, respectively, “3” is set in the start sequence number field. Is set. The Bitmap field is 10110000 because the bits corresponding to the bit positions of sequence numbers = 3, 5 and 6 are “1”. On the other hand, when the CRC results of sequence numbers = 3, 4, 5, and 6 are NG, NG, OK, and OK, respectively, “5” is set in the start sequence number field. The Bitmap field is 11000000 because the bits corresponding to the bit positions of sequence numbers 5 and 6 are “1”.

  Thus, the relationship between the bit position in the Bitmap and the sequence number depends on the value set in the start sequence number field. That is, the sequence number corresponding to each bit position of the bitmap can be specified by the start sequence number field.

  The wireless terminal that has transmitted the super frame receives the delivery confirmation response frame, and identifies its own Bitmap field from among a plurality of existing Bitmap fields. From the value set in the start sequence number field corresponding to its own device and the identified bitmap information, the wireless terminal grasps the CRC result of each data frame transmitted by itself in the superframe.

  For example, if “5” is set in the start sequence number field even though a superframe in which sequence numbers = 3, 4, 5, 6 are aggregated is transmitted, the sequence number = Although the CRC results of 3 and 4 are not reflected, it is recognized that the data frames of sequence numbers 3 and 4 could not be transmitted correctly. For data frames that are confirmed to have not been transmitted correctly by referring to the start sequence number field and the Bitmap field, retransmission processing of the data frames is performed as necessary.

  As described above, even when each wireless terminal transmits a superframe in which a plurality of data frames are aggregated in uplink multiuser MIMO by the configuration of the delivery confirmation response frame in the second embodiment, for each wireless terminal, The delivery confirmation response can be performed with high efficiency.

(Third embodiment)
FIG. 8 shows an example of a hardware configuration of a wireless communication device mounted on an access point according to the third embodiment. This configuration example is an example, and the present embodiment is not limited to this. Since the basic operation is the same as that of the wireless communication apparatus shown in FIG. 5, the difference in configuration will be mainly described, and a duplicate description will be omitted.

  This wireless communication apparatus includes a baseband unit 111, an RF unit 121, and antennas 12A to 12D.

  The baseband unit 111 includes a control circuit (protocol stack) 112, a transmission processing circuit 113, a reception processing circuit 114, DA conversion circuits 115 and 116, and AD conversion circuits 117 and 118. The RF unit 121 and the baseband unit 111 may be configured by a one-chip IC (Integrated Circuit).

  The baseband unit 111 is, for example, a baseband LSI or a baseband IC. As another example, the baseband unit 111 may include an IC 132 and an IC 131. At this time, the IC 132 may include the control circuit 112, the transmission processing circuit 113, and the reception processing circuit 114, and the IC 131 may include the DA conversion circuits 115 and 116 and the AD conversion circuits 117 and 118.

  The control circuit 112 corresponds to, for example, a communication control device that controls communication or a control unit that controls communication. At this time, the wireless communication unit may include a transmission processing circuit 113 and a reception processing circuit 114. Further, the wireless communication unit may include DAs 115 and 116 and DAs 117 and 118 in addition to the transmission processing circuit 113 and the reception processing circuit 114. Further, the wireless communication unit may include a transmission circuit 122 and a reception circuit 123 in addition to the transmission processing circuit 113, the reception processing circuit 114, the DA 115 and 116, and the DA 117 and 118.

  Alternatively, the IC 132 may correspond to a communication control device that controls communication. At this time, the wireless communication unit may include a transmission circuit 122 and a reception circuit 123. Further, the wireless communication unit may include DAs 115 and 116 and DAs 117 and 118 in addition to the transmission circuit 122 and the reception circuit 123.

  The control circuit 112 in the baseband unit 111 includes the buffer 104 in FIG. 7, and performs processing such as a MAC layer. The control circuit 112 may include a clock generation unit. The transmission processing circuit 113 performs desired physical layer processing such as modulation processing and addition of a physical header. The DA conversion circuits 115 and 117 DA convert the frames processed by the transmission processing circuit 113. Here, two systems of DA conversion circuits are provided and are processed in parallel, but one DA conversion circuit may be provided or the number of antennas may be provided.

  The RF unit 121 is, for example, an RF analog IC or a high frequency IC. The transmission circuit 122 in the RF unit 121 uses a transmission filter that extracts a signal of a desired band from the signal of the frame after DA conversion, and a signal of a constant frequency supplied from the oscillation device, and converts the filtered signal to a radio frequency. Includes a mixer for up-conversion and a preamplifier (PA) for amplifying the signal after up-conversion.

  The receiving circuit 123 in the RF unit 121 uses an LNA (low noise amplifier) that amplifies the signal received by the antenna, and uses a constant frequency signal supplied from the oscillation device to downconvert the amplified signal to baseband. And a receiving filter for extracting a signal in a desired band from the signal after down-coating.

  AD conversion circuits 117 and 118 in the baseband unit 111 AD convert the input signal from the reception circuit 123. Here, two AD conversion circuits are provided and are processed in parallel, but one AD conversion circuit may be provided or the number of antennas may be provided. The reception processing circuit 114 performs physical layer processing, demodulation processing, and the like. The control circuit 112 performs processing such as a MAC layer on the demodulated frame. The control circuit 112 performs processing related to MIMO. For example, propagation path estimation processing, transmission weight calculation processing, stream separation processing, and the like are performed.

  Note that a switch for switching the antennas 12A to 12D to any one of the transmission circuit 122 and the reception circuit 123 may be disposed in the RF unit. By the switch control, the antennas 12A to 12D are connected to the transmission circuit 122 during transmission, and the antennas 12A to 12D are connected to the reception circuit 123 during reception.

  Details of the processing of each unit described above are self-explanatory from the description of FIG.

  FIG. 9 shows an example of a hardware configuration of a wireless communication device mounted on a wireless terminal according to the third embodiment. This configuration example is an example, and the present embodiment is not limited to this. Since the basic operation is the same as that of the wireless communication apparatus shown in FIG. 6, the description will focus on the difference in configuration, and a duplicate description will be omitted.

  This wireless communication apparatus includes a baseband unit 211, an RF unit 221, and an antenna 1A. The RF unit 221 and the baseband unit 211 may be configured by a one-chip IC.

  The baseband unit 211 includes a control circuit (protocol stack) 212, a transmission processing circuit 213, a reception processing circuit 214, DA conversion circuits 215 and 216, and AD conversion circuits 217 and 218.

  The baseband unit 211 is, for example, a baseband LSI or a baseband IC. As another example, the baseband unit 211 may include an IC232 and an IC231. At this time, the IC 232 may include a control circuit 212, a transmission processing circuit 213, and a reception processing circuit 214, and the IC 231 may include DA conversion circuits 215 and 216 and AD conversion circuits 217 and 218.

  The control circuit 212 corresponds to, for example, a communication control device that controls communication or a control unit that controls communication. At this time, the wireless communication unit may include a transmission processing circuit 213 and a reception processing circuit 214. Further, the wireless communication unit may include DA 215 and 216 and DA 217 and 218 in addition to the transmission processing circuit 213 and the reception processing circuit 214. Further, the wireless communication unit may include a transmission circuit 222 and a reception circuit 223 in addition to the transmission processing circuit 213, the reception processing circuit 214, the DA 215 and 216, and the DA 217 and 218.

  Alternatively, the IC 232 may correspond to a communication control device that controls communication. At this time, the wireless communication unit may include a transmission circuit 222 and a reception circuit 223. Further, the wireless communication unit may include DA 215 and 216 and DA 217 and 218 in addition to the transmission circuit 222 and the reception circuit 223.

  The control circuit 212 in the baseband unit 211 includes the buffer 204 in FIG. 8, and performs processing such as a MAC layer. The control circuit 212 may include a clock generation unit. The transmission processing circuit 213 performs desired physical layer processing such as modulation processing and addition of a physical header. The DA conversion circuits 215 and 217 perform DA conversion on the frame processed by the transmission processing circuit 213. Here, two systems of DA conversion circuits are provided and are processed in parallel, but one DA conversion circuit may be provided.

  The RF unit 221 is, for example, an RF analog IC or a high frequency IC. The transmission circuit 222 in the RF unit 221 uses a transmission filter that extracts a signal in a desired band from the signal of the frame after DA conversion, and a signal with a constant frequency supplied from the oscillation device, and converts the filtered signal to a radio frequency. Includes a mixer for up-conversion and a preamplifier (PA) for amplifying the signal after up-conversion.

  The receiving circuit 223 is an LNA (low noise amplifier) that amplifies the signal received by the antenna, a mixer that downconverts the amplified signal to baseband using a signal of a constant frequency supplied from the oscillation device, and down A reception filter that extracts a signal in a desired band from the signal after the conversion is included.

  The AD conversion circuits 217 and 218 in the baseband unit 211 AD convert the input signal from the reception circuit 223. Here, two AD conversion circuits are provided and are processed in parallel, but one AD conversion circuit may be provided. The reception processing circuit 214 performs physical layer processing, demodulation processing, and the like. The control circuit 212 performs processing such as a MAC layer on the demodulated frame.

  When the wireless terminal includes a plurality of antennas and supports MIMO, the control circuit 212 also performs processing related to MIMO. For example, propagation path estimation processing, transmission weight calculation processing, stream separation processing, and the like are performed.

  Note that a switch for switching the antenna 1A to one of the transmission circuit 222 and the reception circuit 223 may be disposed in the RF unit 221. By switch control, the antenna 1A is connected to the transmission circuit 222 during transmission, and the antenna 1A is connected to the reception circuit 223 during reception.

  Details of the processing of each unit described above are self-explanatory from the description of FIG.

(Fourth embodiment)
FIG. 10A and FIG. 10B are perspective views of wireless devices according to the fourth embodiment, respectively. The wireless device in FIG. 10A is a notebook PC 301, and the wireless device in FIG. 10B is a mobile terminal 321. The notebook PC 301 and the mobile terminal 321 are equipped with wireless communication devices 305 and 315, respectively. As the wireless communication devices 305 and 315, the wireless communication device (FIGS. 6 and 9 etc.) mounted on the wireless terminal described so far, or the wireless communication device mounted on the access point 11 (FIGS. 5 and 8) Etc.) can be used. A wireless device equipped with a wireless communication device is not limited to a notebook PC or a mobile terminal. For example, it can be mounted on a TV, a digital camera, a wearable device, a tablet, a smartphone, and the like.

  Further, the wireless communication device mounted on the wireless terminal or the access point 11 can be mounted on the memory card. FIG. 11 shows an example in which the wireless communication device is mounted on a memory card. The memory card 331 includes a wireless communication device 355 and a memory card main body 332. The memory card 331 uses a wireless communication device 335 for wireless communication with an external device (such as a wireless terminal or the access point 11). In FIG. 11, description of other elements (for example, a memory) in the memory card 331 is omitted.

(Fifth embodiment)
In the fifth embodiment, in addition to the configuration of the wireless communication device (access point wireless communication device or wireless terminal wireless communication device) according to any one of the first to fourth embodiments, a bus, a processor unit, and an external device An interface unit is provided. The processor unit and the external interface unit are connected to the buffer via the bus. Firmware operates in the processor unit. As described above, by configuring the firmware to be included in the wireless communication device, it is possible to easily change the function of the wireless communication device by rewriting the firmware.

(Sixth embodiment)
In the sixth embodiment, in addition to the configuration of the wireless communication device (access point wireless communication device or wireless terminal wireless communication device) according to any one of the first to fourth embodiments, a clock generation unit is provided. The clock generation unit generates a clock and outputs the clock from the output terminal to the outside of the wireless communication device. Thus, the host side and the wireless communication apparatus side can be operated in synchronization by outputting the clock generated inside the wireless communication apparatus to the outside and operating the host side with the clock output to the outside. It becomes possible.

(Seventh embodiment)
In the seventh embodiment, in addition to the configuration of the wireless communication device (access point wireless communication device or wireless terminal wireless communication device) according to any one of the first to fourth embodiments, a power supply unit, a power supply control unit, And a wireless power feeder. The power supply control unit is connected to the power supply unit and the wireless power supply unit, and performs control to select a power supply to be supplied to the wireless communication device. As described above, by providing the wireless communication apparatus with the power supply, it is possible to perform a low power consumption operation by controlling the power supply.

(Eighth embodiment)
In the eighth embodiment, a SIM card is included in addition to the configuration of the wireless communication apparatus according to the seventh embodiment. The SIM card is connected to a transmission unit (102 or 202), a reception unit (103 or 203), or a control unit (101 or 201) in the wireless communication apparatus. As described above, the authentication process can be easily performed by providing the wireless communication apparatus with the SIM card.

(Ninth embodiment)
The ninth embodiment includes a moving image compression / decompression unit in addition to the configuration of the wireless communication apparatus according to the fifth embodiment. The moving image compression / decompression unit is connected to the bus. As described above, by providing the wireless communication device with the moving image compression / decompression unit, it is possible to easily transmit the compressed moving image and expand the received compressed moving image.

(Tenth embodiment)
In the tenth embodiment, in addition to the configuration of the wireless communication device (access point wireless communication device or wireless terminal wireless communication device) according to any one of the first to fourth embodiments, an LED unit is included. The LED unit is connected to the transmission unit (102 or 202), the reception unit (103 or 203), or the control unit (101 or 201). As described above, by providing the wireless communication device with the LED unit, it is possible to easily notify the user of the operation state of the wireless communication device.

(Eleventh embodiment)
The eleventh embodiment includes a vibrator unit in addition to the configuration of the wireless communication device (access point wireless communication device or wireless terminal wireless communication device) according to any one of the first to fourth embodiments. The vibrator unit is connected to the transmission unit (102 or 202), the reception unit (103 or 203), or the control unit (101 or 201). As described above, by providing the radio communication device with the vibrator unit, it is possible to easily notify the user of the operation state of the radio communication device.

(Twelfth embodiment)
In this embodiment, [1] frame type in the wireless communication system, [2] connection disconnection method between wireless communication apparatuses, [3] access method of wireless LAN system, and [4] wireless LAN frame interval will be described.
[1] Frame types in a communication system Generally, frames handled in a radio access protocol in a radio communication system are roughly classified into three types: a data frame, a management frame, and a control frame. These types are usually indicated by a header portion provided in common between frames. As a display method of the frame type, three types may be distinguished by one field, or may be distinguished by a combination of two fields.

  The management frame is a frame used for managing a physical communication link with another wireless communication apparatus. For example, there are a frame used for setting communication with another wireless communication device, a frame for releasing a communication link (that is, disconnecting), and a frame related to a power saving operation in the wireless communication device. .

  The data frame is a frame for transmitting data generated inside the wireless communication device to the other wireless communication device after establishing a physical communication link with the other wireless communication device. Data is generated in an upper layer of the present embodiment, for example, generated by a user operation.

  The control frame is a frame used for control when a data frame is transmitted / received (exchanged) to / from another wireless communication apparatus. When the wireless communication apparatus receives a data frame or a management frame, the response frame transmitted for confirmation of delivery belongs to the control frame.

  These three types of frames are sent out via the antenna as physical packets through processing as required in the physical layer. In the connection establishment procedure, a connection request frame and a connection acceptance frame are management frames, and a response frame of a control frame can be used as a confirmation frame for the connection acceptance frame.

[2] Methods for disconnecting connections between wireless communication devices There are explicit and implicit methods for disconnecting connections. As an explicit method, one of the connected wireless communication apparatuses transmits a frame for disconnection. This frame is classified as a management frame. The frame for disconnection may be called a release frame in the sense that, for example, the connection is released. Usually, the wireless communication device that transmits the release frame determines that the connection is disconnected when the release frame is transmitted and the wireless communication device that receives the release frame receives the release frame. Thereafter, the process returns to the initial state in the communication phase, for example, the state of searching for the wireless communication device of the communication partner. This is because when a frame for disconnection is transmitted, a physical radio link may not be secured such that a radio signal cannot be received or decoded due to a communication distance away from the connection destination radio communication device. Because.

  On the other hand, as an implicit method, a frame transmission (transmission of a data frame and a management frame, or transmission of a response frame to a frame transmitted by the own device) is detected from a wireless communication device of a connection partner that has established a connection for a certain period of time. If not, it is determined whether the connection is disconnected. There is such a method in the situation where it is determined that the connection is disconnected as described above, such that the communication distance is away from the connection-destination wireless communication device, and the wireless signal cannot be received or decoded. This is because a wireless link cannot be secured. That is, it cannot be expected to receive a release frame.

  As a specific example of determining the disconnection by an implicit method, a timer is used. For example, when transmitting a data frame requesting a delivery confirmation response frame, a first timer that limits the retransmission period of the frame is started (for example, a retransmission timer for a data frame), and until the first timer expires (that is, If a delivery confirmation response frame is not received (until the desired retransmission period elapses), retransmission is performed. The first timer is stopped when a delivery confirmation response frame for the frame is received.

  On the other hand, when the first timer expires without receiving a delivery confirmation response frame, for example, it is confirmed whether the other party's wireless communication device still exists (within the communication range) (in other words, a wireless link has been secured). And a second timer for limiting the retransmission period of the frame (for example, a retransmission timer for the management frame) is started at the same time. Similar to the first timer, the second timer also performs retransmission if it does not receive an acknowledgment frame for that frame until the second timer expires, and determines that the connection has been disconnected when the second timer expires .

  Alternatively, when a frame is received from the connection partner wireless communication device, the third timer is started. Whenever a new frame is received from the connection partner wireless communication device, the third timer is stopped and started again from the initial value. When the third timer expires, a management frame is transmitted to confirm whether the other party's wireless communication device still exists (within the communication range) (in other words, whether the wireless link has been secured) as described above. At the same time, a second timer (for example, a retransmission timer for management frames) that limits the retransmission period of the frame is started. In this case as well, retransmission is performed if a delivery confirmation response frame to the frame is not received until the second timer expires, and it is determined that the connection is disconnected when the second timer expires. The latter management frame for confirming whether the wireless communication apparatus of the connection partner still exists may be different from the management frame in the former case. In the latter case, the same timer as used in the former case is used as the second timer for limiting the retransmission of the management frame. However, a different timer may be used.

[3] Wireless LAN system access method For example, there is a wireless LAN system that is assumed to communicate or compete with a plurality of wireless communication devices. In IEEE802.11 (including extended standards) wireless LANs, CSMA / CA is the basic access method. In the method of grasping the transmission of a certain wireless communication device and performing transmission after a fixed time from the end of the transmission, the transmission is performed simultaneously by a plurality of wireless communication devices grasping the transmission of the wireless communication device, and as a result The radio signal collides and frame transmission fails. By grasping the transmission of a certain wireless communication device and waiting for a random time from the end of the transmission, the transmissions by a plurality of wireless communication devices that grasp the transmission of the wireless communication device are stochastically dispersed. Therefore, if there is one wireless communication device that has drawn the earliest time in the random time, the frame transmission of the wireless communication device is successful, and frame collision can be prevented. Since acquisition of transmission rights is fair among multiple wireless communication devices based on random values, the method employing Carrier Avoidance is a suitable method for sharing wireless media among multiple wireless communication devices. be able to.

[4] Wireless LAN frame interval
The frame interval of IEEE 802.11 wireless LAN will be described. Frame intervals used in IEEE 802.11 wireless LAN are distributed coordination function interframe space (DIFS), arbitration interframe space (AIFS), point coordination function interframe space (PIFS), short interframe space (SIFS), and extended interframe space (EIFS). There are 6 types of reduced interframe space (RIFS).

  In the IEEE802.11 wireless LAN, the frame interval is defined as a continuous period that should be opened after confirming carrier sense idle before transmission, and a strict period from the previous frame is not discussed. Therefore, in the description of the IEEE802.11 wireless LAN system here, the definition follows. In IEEE802.11 wireless LAN, the waiting time for random access based on CSMA / CA is the sum of fixed time and random time, and it can be said that such a definition is used to clarify the fixed time.

  DIFS and AIFS are frame intervals used when attempting to start frame exchange during a contention period competing with other wireless communication devices based on CSMA / CA. DIFS is used when priority according to traffic type (Traffic Identifier: TID) is provided when priority is not distinguished by traffic type.

  Since the operations related to DIFS and AIFS are similar, the following description will be made mainly using AIFS. In the IEEE802.11 wireless LAN, access control including the start of frame exchange is performed at the MAC layer. Further, when QoS (Quality of Service) is supported when data is transferred from an upper layer, the traffic type is notified together with the data, and the priority of the data is classified based on the traffic type. This access class is called an access category (AC). Therefore, an AIFS value is provided for each access category.

  PIFS is a frame interval for enabling access having priority over other competing wireless communication devices, and has a shorter period than either value of DIFS and AIFS. SIFS is a frame interval that can be used when a response control frame is transmitted or when frame exchange is continued in a burst after acquiring the access right. EIFS is a frame interval that is triggered when frame reception fails.

  RIFS is a frame interval that can be used when a plurality of frames are continuously transmitted to the same wireless communication device in bursts after acquiring the access right. While using RIFS, from the wireless communication device of the transmission partner Do not request a response frame.

  Here, FIG. 12 shows an example of a frame exchange during a contention period based on random access in the IEEE 802.11 wireless LAN.

  A case is assumed in which when a transmission request for a data frame (W_DATA1) is generated in a certain wireless communication apparatus, the medium is recognized as a busy medium as a result of carrier sense. In this case, a fixed time AIFS is vacated after the carrier sense becomes idle, and then a data frame W_DATA1 is transmitted to the communication partner when a random time (random backoff) is vacant.

  The random time is obtained by multiplying a pseudo-random integer derived from a uniform distribution between contention windows (CW) given by an integer from 0 to a slot time. Here, the CW multiplied by the slot time is called the CW time width. The initial value of CW is given by CWmin, and every time retransmission is performed, the value of CW is increased until it reaches CWmax. Both CWmin and CWmax have values for each access category similar to AIFS. When the wireless communication device as the transmission destination of W_DATA1 succeeds in receiving the data frame, it transmits a response frame (W_ACK1) after SIFS from the reception end time. The wireless communication apparatus that has transmitted W_DATA1 can transmit the next frame (for example, W_DATA2) after SIFS if W_ACK1 is received and within the transmission burst time limit.

  AIFS, DIFS, PIFS, and EIFS are functions of SIFS and slot time. SIFS and slot time are defined for each physical layer. In addition, parameters that have a value for each access category such as AIFS, CWmin, and CWmax can be set for each communication group (Basic Service Set (BSS) in IEEE802.11 wireless LAN), but default values are set. .

  For example, in the 802.11ac standard formulation, SIFS is 16 μs and slot time is 9 μs, so that PIFS is 25 μs, DIFS is 34 μs, AIFS access category is background (AC_BK) frame interval default value is 79 μs, The default frame interval for BEST EFFORT (AC_BE) is 43 μs, the default frame interval for VIDEO (AC_VI) and VOICE (AC_VO) is 34 μs, and the default values for CWmin and CWmax are 31 and 1023 for AC_BK and AC_BE, respectively. Suppose AC_VI is 15 and 31, and AC_VO is 7 and 15. Note that EIFS is the sum of the time lengths of response frames when transmitting at the slowest required physical rate with SIFS and DIFS. In the present embodiment, a wireless communication system using such a frame interval parameter is assumed as an interference system having a wide communication range.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

1: Access point (wireless terminal)
12A, 12B, 12C, 12D: Antenna
1, 2, 3, and 4: Wireless terminals
1A, 2A, 3A, 4A: Antenna
21, 22, 23, 24: Beam
51: Notification frame
T1, T2: Period
101, 201: Control unit
102, 202: Transmitter
103, 203: Receiver
104, 204: Buffer
111, 211: Baseband part
121, 221: RF section
122, 222: Transmitter circuit
123, 223: Receiver circuit
112, 212: Control circuit
113, 213: Transmission processing circuit
114, 214: Reception processing circuit
115, 116, 215, 216: DA conversion circuit
117, 118, 217, 218: AD conversion circuit
301: Notebook PC
305, 315, 355: Wireless communication devices
321: Mobile terminal
331: Memory card
332: Memory card body

Claims (37)

A communication control device for controlling communication with a plurality of target communication devices used in a wireless communication device having a wireless communication unit,
A frame transmitted by spatial multiplexing is received from each of the plurality of target communication devices via the wireless communication unit,
A control unit that transmits a delivery confirmation response frame including a test result indicating whether or not each of the frames transmitted from the plurality of target communication devices has been successfully received to the plurality of target communication devices via the wireless communication unit; Communication control device provided. The control unit transmits a first frame including notification information specifying the plurality of target communication devices to the plurality of target communication devices via the wireless communication unit, and the plurality of targets specified by the notification information The communication control device according to claim 1, wherein the frame transmitted by the spatial multiplexing is received from a communication device. The communication control device according to claim 2, wherein the delivery confirmation response frame includes a bit map representing a result of checking whether or not the frame transmitted from the plurality of target communication devices has been successfully received. The notification information of the first frame specifies identification information of the plurality of target communication devices in a first order,
The communication control device according to claim 2, wherein the control unit assigns the inspection result of each target communication device to the bitmap according to the first order. The communication according to claim 4, wherein the control unit assigns the inspection result of each target communication device in order from a bit at a predetermined position in the bitmap in a lower or upper bit direction according to the first order. Control device. The plurality of target communication devices belong to the same group,
The control unit arranges a group number of a group to which the plurality of target communication devices belong, and transmits a second frame in which identification information of the plurality of target communication devices belonging to the group is arranged in a second order,
The notification information of the first frame specifies a group number of a group to which the plurality of target communication devices belong,
The communication control device according to claim 3, wherein the control unit assigns the inspection result of each target communication device to the bitmap according to the second order. 7. The communication according to claim 6, wherein the control unit assigns the inspection result of each target communication device in order from a bit at a predetermined position in the bitmap in a lower or upper bit direction according to the second order. Control device. The communication control device according to claim 5 or 7, wherein the bit at the predetermined position is a least significant bit or a most significant bit of the bitmap. The communication control device according to claim 1, wherein a destination address of the delivery confirmation response frame is a broadcast address or a multicast address to which the plurality of target communication devices belong. The communication control device according to claim 1, wherein a destination address of the delivery confirmation response frame is a unicast address of any one of the plurality of target communication devices. The size of the bitmap field in the acknowledgment frame is equal to or greater than the maximum number of communication devices that can be specified in the first frame or the maximum number of data streams that can be formed by the wireless communication unit. The communication control apparatus according to any one of the above. The notification information of the first frame specifies identification information of the plurality of target communication devices in a first order,
From each target communication device, an aggregation frame that aggregates a plurality of frames each assigned a sequence number is transmitted,
The delivery confirmation response frame includes, for each aggregation frame, identification information for identifying the smallest sequence number among frames that have been successfully received in the aggregation frame, and frames having sequence numbers after the smallest sequence number. The communication control device according to claim 2, wherein bit maps representing the inspection results are arranged in accordance with the first order. The communication control device according to claim 12, wherein the control unit sets the inspection result of the frame having the sequence number after the smallest sequence number in order of the sequence number from the bit at the predetermined position of the bitmap to the lower or upper bit direction. . The communication control device according to claim 13, wherein the bit at the predetermined position is a least significant bit or a most significant bit of the bitmap. The number of bitmap fields in the delivery confirmation response frame is equal to or greater than the maximum number of communication devices that can be specified in the first frame or the maximum number of data streams that can be formed by the wireless communication unit,
The communication control device according to any one of claims 12 to 14, wherein a size of the bitmap field is equal to or larger than a maximum number of bits that can be aggregated in the aggregation frame. The communication control device according to any one of claims 1 to 15, wherein the control unit controls communication according to an IEEE802.11 standard. A communication control device according to any one of claims 1 to 16;
The wireless communication unit;
A wireless terminal comprising at least one antenna. A communication control device according to any one of claims 1 to 16;
The wireless communication unit;
A memory card with at least one antenna.   An integrated circuit comprising a communication control device according to any one of the preceding claims. A communication control device according to any one of claims 1 to 16;
An integrated circuit including the wireless communication unit. A communication control device for controlling communication with a target communication device used in a wireless communication device having a wireless communication unit,
Transmitting a frame to the target communication device via the wireless communication unit so as to be orthogonal to a frame signal transmitted by another wireless communication device among the plurality of wireless communication devices;
A delivery confirmation response frame including a test result indicating whether or not each of the target communication devices has successfully received frames transmitted from a plurality of target communication devices including the wireless communication device is transmitted through the wireless communication unit. Received from the communication device,
An inspection result for the frame transmitted by the wireless communication device is identified from the delivery confirmation response frame, and whether the frame transmitted to the target communication device has been successfully received by the target communication device based on the identified inspection result. A communication control device comprising a control unit for judging. The control unit receives a first frame including notification information designating a plurality of wireless communication devices including the wireless communication device from the target communication device via the wireless communication unit, and receives the first frame. The communication control apparatus according to claim 21, wherein the frame is transmitted after a predetermined first time has elapsed. The notification information of the first frame specifies identification information of a plurality of wireless communication devices including the wireless communication device in a first order,
The delivery confirmation response frame includes a bit map indicating a result of checking whether or not a frame transmitted from a plurality of wireless communication devices including the wireless communication device has been successfully received,
The control unit specifies a bit position in the bitmap according to the rank of identification information of the wireless communication device in the first order, and specifies the inspection result based on the bit at the specified bit position. Item 23. The communication control device according to Item 22. A plurality of target communication devices including the wireless communication device belong to the same group,
The control unit arranges group numbers of groups to which a plurality of wireless communication devices including the wireless communication device belong, and identifies identification information of the plurality of wireless communication devices including the wireless communication devices belonging to the group in a second order. Send the arranged second frame,
The notification information of the first frame specifies a group number of a group to which the plurality of target communication devices belong,
The delivery confirmation response frame includes a bit map representing a result of checking whether or not the frame transmitted from a plurality of wireless communication devices including the wireless communication device has been successfully received,
The control unit specifies a bit position in the bitmap according to the order of identification information of the wireless communication device in the second order, and specifies the inspection result based on the bit of the specified bit position. Item 23. The communication control device according to Item 22. 25. The inspection result is specified based on a bit at a position moved from a bit at a predetermined position of the bitmap in a lower or upper bit direction by a number corresponding to the order of identification information of the wireless communication device. The communication control device according to 1. The communication control device according to any one of Claims 25, wherein the bit at the predetermined position is a least significant bit or a most significant bit of the bitmap. In the notification information of the first frame, identification information of a plurality of wireless communication devices including the wireless communication device is arranged in a first order,
The control unit transmits an aggregation frame obtained by aggregating a plurality of frames each assigned a sequence number,
The delivery confirmation response frame includes, for each aggregation frame, identification information for identifying the smallest sequence number among frames that have been successfully received in the aggregation frame, and frames having sequence numbers after the smallest sequence number. Bitmaps representing inspection results in bits are arranged according to the first order,
The communication control device according to claim 22, wherein the control unit specifies the specific information and the bitmap for the wireless communication device according to a rank of identification information of the wireless communication device in the first order. . The control unit specifies the inspection result of a frame having a sequence number after the sequence number specified by the specifying information in order from a bit at a predetermined position in the specified bit map in a lower or upper bit direction. 27. The communication control device according to 27. The communication control device according to claim 28, wherein the bit at the predetermined position is a least significant bit or a most significant bit of the bitmap. When the destination address of the delivery confirmation response frame is a unicast address of another wireless communication device specified by the notification information of the first frame, the control unit sends the delivery confirmation response frame to the wireless communication device. 30. The communication control device according to claim 22, wherein the communication control device is determined to be addressed. The communication control device according to any one of claims 21 to 30, wherein the control unit controls communication according to an IEEE802.11 standard. A communication control device according to any one of claims 21 to 31;
The wireless communication unit;
A wireless terminal comprising at least one antenna. A communication control device according to any one of claims 21 to 31;
The wireless communication unit;
A memory card with at least one antenna.   32. An integrated circuit comprising a communication control device according to any one of claims 21 to 31. A communication control device according to any one of claims 21 to 31;
An integrated circuit including the wireless communication unit. A communication control method for controlling communication with a plurality of target communication devices used in a wireless communication device having a wireless communication unit,
Receiving a frame transmitted by spatial multiplexing from each of the plurality of target communication devices;
Transmitting a delivery confirmation response frame including an inspection result as to whether or not each of the frames transmitted from the plurality of target communication devices has been successfully received, to the plurality of target communication devices. A wireless communication method by a wireless communication device,
Transmitting a frame to the target communication device so as to be orthogonal to a signal of a frame transmitted by another wireless communication device among a plurality of wireless communication devices;
Receiving, from the target communication device, a delivery confirmation response frame including a test result as to whether each of the target communication devices has successfully received the frame transmitted from a plurality of target communication devices including the wireless communication device; ,
An inspection result for the frame transmitted by the wireless communication device is identified from the delivery confirmation response frame, and whether the frame transmitted to the target communication device has been successfully received by the target communication device based on the identified inspection result. A wireless communication method comprising: a step of determining.

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