RU2780583C2 - Communication apparatus and communication method - Google Patents

Abstract

FIELD: wireless communication.

SUBSTANCE: to realise the technical result, communication apparatus receives a starting frame containing a first user information field and a second user information field. The first user information field comprises a first terminal identifier (ID) subfield and a first resource unit (RU) selection subfield, and the second user information field comprises a second terminal ID subfield and a second RU selection subfield. The value not subject to use by the terminal ID is therein set in the first random access terminal ID subfield, the first RU selection subfield indicates the initial RU of one or more adjacent random access RU (RA-RU), and the first user information field additionally comprises the first RA-RU number subfield indicating the first number of RU in said one or more adjacent RA-RU. The transmitter of the apparatus then transmits an uplink signal using at least one of said one or more adjacent RA-RU.

EFFECT: reduction in the size of the starting frame.

10 cl, 26 dwg

Description

Technical field

[0001] The present invention relates to a communication device and a communication method.

State of the art

[0002] In the IEEE 802.11 (Institute of Electrical and Electronics Engineers) Working Group, the ax Task Force worked to create the IEEE 802.11ax (hereinafter referred to as "11ax") specification as the next version of the 802.11ac standard. In 11ax, random access (RA) based on OFDMA (Orthogonal Frequency Division Multiple Access) was introduced.

[0003] An access point (AP, also referred to as a “base station”) transmits, to a plurality of terminals (also referred to as STAs (stations)) associated with the AP, a control signal to cause them to transmit an uplink OFDMA signal (hereinafter, this signal control is referred to as a "start frame").

[0004] In the start frame, a general information field and a user information field are defined. The common information field includes information that is common among a plurality of terminals multiplexed by OFDMA. The user information field includes information specific to each of the terminals multiplexed by OFDMA (eg, see NPL 1 and NPL 4).

[0005] The general information field includes a trigger type subfield specifying a trigger type indicating a trigger frame type (the signal type by which the AP instructs the terminal to transmit) (eg, see NPL 2 and NPL 3).

[0006] The user information field includes an AID12 subfield used to inform an association identifier (AID), which is an identifier uniquely assigned to a terminal when the terminal is associated. Hereinafter, "scheduled access" means a method in which an AID assigned to a particular terminal is reported to the terminal, thereby allocating a frequency resource block (RU) to the terminal. Moreover, in 11ax, it was agreed that, by setting one of the unused AIDs such that AID=0, each terminal is informed that the frequency resource (RU) specified in the RU selection subfield from the user information field is the RU for RA (RA-RU) (for example, see NPL 1).

[0007] Moreover, during the meeting on 11ax, it was further agreed that the start frame may include a new user field (called "modified user information") intended for RA (NPL 5). In the modified user information, one user information field specifies one or more adjacent RA-RUs for the terminal.

List of opposed materials

Non-Patent Literature

[0008] NPL 1: IEEE 802.11-15/0132r17 "Specification Framework for TGax"

NPL 2: IEEE 802.11-16/0024r1 "Proposed TGax draft specification"

NPL 3: IEEE 802.11-16/0806r0 "HE Variant HT Control - Buffer Status Report"

NPL 4: IEEE 802.11-16/0617r1 "Remaining Topics in Power Control"

NPL 5: IEEE 802.11-16/1516r1 "CIDs for: Section 9.3.1.23 Random Access CIDs"

NPL 6: IEEE 802.11-16/0725r3 "CIDs for: Trigger Frame Format Comment Resolution - Type Dependent Per user information section 9.3.1.23" each user")

NPL 7: IEEE 802.11-16/0938r1 "Resolution for CID 1589, 1590, 2668, and 2669 on Multi-TID Aggregation in Sub-clause 25.10.4" TID in sub-clause 25.10.4")

The essence of the invention

[0009] However, no sufficient discussion has been held on how to apply the modified user information in the start frame.

[0010] In an aspect, the present invention provides a communication apparatus and a communication method capable of appropriately setting modified user information in a start frame.

[0011] According to an aspect of the present invention, a communication device includes a trigger generator that generates a trigger instructing transmission of an uplink signal, the trigger includes a terminal information field that includes a terminal identifier subfield and a allocation of a resource block, wherein, in the case where the trigger includes a first terminal information field specifying one or more contiguous random access resource blocks, an unused identifier that cannot be used as a terminal identifier is set in the terminal identifier subfield in the first terminal information field, and a transmitter that transmits the generated start signal.

[0012] General or specific embodiments may be implemented as a system, device, method, integrated circuit, computer program, or storage medium, or any combination of system, device, method, integrated circuit, computer program, and storage medium.

[0013] According to an aspect of the present invention, it is possible to appropriately set the modified user information in the start frame.

[0014] Additional benefits and advantages of the disclosed embodiments will become apparent from the description of the invention and the drawings. Benefits and/or advantages may be obtained individually by various embodiments and features of the description and drawings, which need not be all provided in order to achieve one or more of such benefits and/or advantages.

Brief description of the drawings

[0015] FIG. 1 is a diagram illustrating the start frame format.

Fig. 2 is a diagram illustrating the format of a common information field of a starting frame.

Fig. 3 is a diagram illustrating a trigger type of a frame trigger.

Fig. 4 is a diagram illustrating the format of a user information field of a trigger frame.

Fig. 5 is a diagram illustrating the format of a user information field from a trigger-dependent user information field.

Fig. 6A is a diagram illustrating the format of a modified start frame user information field.

Fig. 6B is a diagram illustrating an example of RA-RUs given by a modified user information field.

Fig. 7 is a block diagram illustrating an example of a partial configuration of an AP according to the first embodiment.

Fig. 8 is a block diagram illustrating a configuration example of an AP according to the first embodiment.

Fig. 9 is a block diagram illustrating a configuration of a terminal according to the first embodiment.

Fig. 10 is a diagram illustrating an example (Special Example 1-1) of RA-RU defined by modified user information according to the first embodiment.

Fig. 11 is a diagram illustrating an example (Special Example 1-2) of RA-RU defined by modified user information according to the first embodiment.

Fig. 12 is a diagram illustrating an example (Special Example 1-2) of RA-RU defined by modified user information according to the first embodiment.

Fig. 13 is a diagram illustrating an example (Special Example 1-2) of RA-RU defined by user information according to the first embodiment.

Fig. 14 is a diagram illustrating an example (Special Example 2) of RA-RU defined by user information according to the first embodiment.

Fig. 15 is a diagram illustrating an example (Special Example 2) of RA-RU defined by user information according to the first embodiment.

Fig. 16 is a diagram illustrating an example (Special Example 2-1) of RA-RU defined by user information according to the first embodiment.

Fig. 17 is a diagram illustrating an example (Special Example 2-2) of RA-RU defined by modified user information according to the first embodiment.

Fig. 18 is a diagram illustrating an example (Special Example 2-2) of RA-RU defined by modified user information according to the first embodiment.

Fig. 19 is a block diagram illustrating a configuration example of an AP according to the second embodiment.

Fig. 20 is a block diagram illustrating a configuration example of a terminal according to the second embodiment.

Fig. 21 is a diagram illustrating an example (Special Example 1) of RA-RU defined by user information according to the second embodiment.

Fig. 22 is a diagram illustrating an example (Special Example 2) of RA-RU defined by user information according to the second embodiment.

Fig. 23 is a diagram illustrating an example (Special Example 3) of RA-RU defined by user information according to the second embodiment.

Fig. 24 is a diagram illustrating an example of RA-RU defined by user information according to another embodiment.

Fig. 25 is a diagram illustrating an example of a start frame configuration according to another embodiment.

Description of Embodiments

[0016] Embodiments of the present invention are described in detail below with reference to the drawings. In the embodiments described below, like elements are designated by like reference symbols, and their exact repetitive description is omitted.

[0017] (First embodiment)

[Starting Frame]

Fig. 1 is a diagram illustrating an example of the start frame format discussed in 11ax. The start frame defines a common information field including information that is common among a plurality of OFDMA multiplexed terminals and a user information field including specific information for each of the OFDMA multiplexed terminals (eg, see NPL 1).

[0018] FIG. 2 is a diagram illustrating an example of a start frame common information field format (eg, see NPL 1). The trigger type subfield specifies the trigger type. Fig. 3 illustrates certain trigger types (eg see NPL 2). It is discussed to define an additional trigger type for causing the terminal to report transmission buffer information (hereinafter referred to as Buffer Status Report Sending (BSRP)) in addition to the specific trigger types shown in FIG. 3 (for example, see NPL 3). The trigger dependent general information field may include general terminal information suitable for (depending on) a particular trigger type.

[0019] FIG. 4 is a diagram illustrating an example of the start frame user information field format (eg, see NPL 1 and NPL 4). In the format shown in FIG. 4, the size of the Target RSSI (Received Signal Strength Indicator) subfield, which has not yet been defined in NPL 1, is defined to be seven bits as proposed in NPL 4. The AID12 subfield is used to inform the AID. When AID is set such that AID=0, it is indicated that the RU specified in the user information field is RA-RU (eg, see NPL 1). The trigger-dependent user information field may include terminal-specific information suitable for (depending on) a particular type of trigger.

[0020] Hereinafter, a user information field specifying a radio resource for a terminal in RUs is referred to as "ordinary user information" to distinguish from "modified user information". Ordinary user information and modified user information may be collectively referred to as "user information".

[0021] Moreover, in 11ax, as one of the trigger types, a basic trigger is defined. In the basic trigger, the uplink signal format is not limited to specific formats (eg, see FIG. 3). As a response to the basic trigger signal, a response using scheduled access and a response using random access are provided. In the case where the trigger type is a basic trigger, the trigger type-specific user information subfield of the user information field includes information (restriction information) indicating a restriction on transmission of the uplink signal, as shown in FIG. 5 (for example, see NPL 6 and NPL 7).

[0022] More precisely, as shown in FIG. 5, the type-specific information subfield of each user includes a 2-bit "MU MPDU duty cycle" indicating the minimum allowable interval of an MPDU (MAC protocol data unit) processed by the AP, a 3-bit "TID aggregation limit" indicating the maximum number of TIDs included in the MPDU, a 1-bit "AC preference level" acting as a flag indicating whether to set the access category (AC, type of data to transmit) recommended from the AP, and a 2-bit "AC preference" indicating a parameter indicative of the AC recommended from the AP. These are parameters for using an A-MPDU (MAC Protocol Aggregate Data Unit), which is an aggregate of a plurality of MPDUs, as an uplink signal in response to a start frame, or parameters for specifying an AC to be transmitted.

[0023] [Modified user information]

Fig. 6A is a diagram illustrating an example of a modified user information format.

[0024] In a start frame using normal user information, one random access RU is defined using one user information field. That is, in the start frame using the normal user information to define the RA-RU plurality, the user information fields plurality is used.

[0025] In contrast, in the modified user information, the locations of the given RUs are limited to one solid bar. This makes it possible to specify a plurality of RUs using one modified user information field. For example, in the modified user information shown in FIG. 6A, the RU allocation subfield specifies the location of the initial RU of the RA-RU contiguous band and the size of the RU (see FIG. 6B). Moreover, in the modified user information, when the number of space division multiplexed streams in RA-RU transmission is limited to "1" (ie, MIMO is not used), the SS allocation subfield shown in FIG. 6A specifies not the number of space division multiplexed streams, but the number of RA-RUs (number of contiguous RUs) starting from the RA-RU declared by the RU allocation subfield (see FIG. 6B). Note that the RU size of each RA-RU is given by the RU size declared by the RU allocation subfield. The information described in the coding type, MCS, DCM, and target RSSI subfields of the modified user information shown in FIG. 6A are common to multiple RA-RUs defined by RU allocation and SS allocation.

[0026] Moreover, in the modified user information, as shown in FIG. 6A, the trigger dependent information subfield has been removed. In the trigger frame using the modified user information, the trigger-dependent general information subfield has been removed. As a result, a reduction in the start frame size is achieved.

[0027] As described above, in the modified user information, a part of the parameters specified by the normal user information is shared by a plurality of RUs (a plurality of terminals), so that one or more adjacent RA-RUs are specified by one user information field, thereby , achieving a reduction in the size of the starting frame.

[0028] The modified user information has been described above.

[0029] According to the present invention, a method for applying modified user information in a start frame is described below.

[0030] For example, in order to apply modified user information, a new trigger type specifying RA transmission (hereinafter referred to as "RA trigger") may be added to the reserved element of the trigger type subfield shown in FIG. 3. When the trigger RA is set as the trigger type, the use of the modified user information enables the trigger frame size to be reduced. Moreover, when the trigger RA is set as the trigger type, by deleting the trigger-dependent general information subfield and the trigger-dependent user information subfield, it becomes possible to reduce the size of the trigger frame.

[0031] However, setting the modified user information by the trigger RA described above uses (consumes) the reserved trigger type field, resulting in a reduction in the additional extension space of the standard.

[0032] Moreover, the trigger RA is allowed to be set only by the modified user information, and thus only one group of contiguous RUs can be set by one parameter. Therefore, in the case where a portion of the RUs existing in the system band is expected to suffer performance degradation (for example, RUs located near DCs or RUs in which interference is observed), it is necessary to set highly error-tolerant robust parameters (for example, MCS) for all RUs given by the modified user information, and thus a reduction in throughput occurs.

[0033] In view of the above, the present invention provides a method for defining a plurality of RA-RUs with a small size trigger frame using modified user information, while maintaining future trigger type extensibility (i.e., without adding a new trigger type such as trigger RA signal, or the like), and a method for setting the RU-specific parameter even if modified user information is applied.

[0034] [Wireless System Configuration]

In the present embodiment, the wireless communication system includes an AP 100 (radio transmitting device) and a terminal 200 (radio receiving device). AP 100 transmits a trigger frame instructing terminal 200 to transmit the RA. Terminal 200 receives the trigger frame and transmits the RA to AP 100 using the resource specified in the trigger frame.

[0035] FIG. 7 is a block diagram partially illustrating the configuration of the AP 100 according to the present embodiment. In AP 100 shown in FIG. 7, the start frame generator 104 generates a start frame (start signal) instructing to transmit an uplink signal. The radio transmitter/receiver 106 transmits a start frame. In the case where the starting frame includes a modified user information field (first terminal information field) specifying one or more contiguous RA-RUs, the starting frame generator 104 sets an unused AID that should not be used as an AID (terminal identifier) , in the AID12 subfield (terminal identifier subfield) in the modified user information field.

[0036] [AP Configuration]

Fig. 8 is a block diagram illustrating the configuration of the AP 100 according to the present embodiment. The AP 100 generates a start frame (start signal) to cause the terminal 200 to transmit an uplink signal (eg, an RA signal), and transmits the generated start frame to the terminal 200.

[0037] FIG. 8, AP 100 includes an RA resource controller 101, a user information controller 102, an AID controller 103, a start frame generator 104, a transmit signal modulator 105, a radio transmitter/receiver 106, an antenna 107, a receive signal demodulator 108, and a quality estimator 109. The radio transmitter/receiver 106 includes a transmitter and a receiver. The RA resource controller 101, the user information controller 102, the AID controller 103, the start frame generator 104, and the quality evaluation unit 109 collectively form a medium access control (MAC) block.

[0038] The RA resource controller 101 determines a band to be allocated to RA-RUs within the system band based on the reception quality for each RU with a predetermined size outputted from the quality estimation unit 109 . The RA resource controller 101 outputs RA resource information indicating the band in which RA-RUs are allocated to the user information controller 102 and the start frame generator 104 .

[0039] The RA resource information, for example, includes information related to RA-RUs allocated within the system bandwidth, control information for generating an RA signal (coding type, MCS, DCM, SS allocation, and target RSSI included in the user information), and/or the like. For example, as for an RU with poor reception quality such as an RU overlapping with a band used by another service in the system band, an RU corresponding to a DC frequency in the baseband, when demodulated, the RU is subjected to relatively strong interference or distortion, the resource controller 101 The RA may apply a highly error-tolerant MCS (eg, BPSK) or a relatively high target RSSI level (eg, -60 dBm). For another RU subject to relatively low interference, the RA resource controller 101 may apply an MCS (eg, 16QAM) that provides higher transmission efficiency, or a target RSSI level (eg, -70 dBm) that causes less interference with the other. terminal.

[0040] The user information controller 102 controls the user information field in the start frame based on the RA resource information output from the RA resource controller 101 and outputs the control result to the start frame generator 104 .

[0041] More specifically, the user information controller 102 determines the format of the user information field (modified user information or normal user information) to be used and the RA-RU to be specified by the user information field. For example, in the case where modified user information is used, the user information controller 102 decides to set a plurality of RA-RUs in the RU allocation and the SS allocation of the user information field, and set a parameter that is common to these RA-RUs. On the other hand, in the case where normal user information is used, the user information controller 102 decides to set one RA-RU in the user information field and set a single parameter related to RA-RU.

[0042] The AID controller 103 determines the AID (the information described in the AID12 subfield of the trigger frame) to set the format of the user information field (modified user information or normal user information). The AID controller 103 outputs AID information indicating the determined AID to the start frame generator 104 .

[0043] For example, the AID controller 103 may set, as an AID for setting RA-RU, an unused AID (in the specification for 11ax, one of AID=0, 2008 to 4094), which should not be used as a terminal specific AID for scheduled access. Details on defining an AID to format the user information field will be described later.

[0044] A trigger frame generator 104 (trigger generator) generates a trigger frame to instruct terminal 200 to perform an RA transmission (e.g., OFDMA-based RA transmission (e.g., see FIG. 1, FIG. 2, FIG. 4, and FIG. 6A) More specifically, based on the information output from the user information controller 102, the start frame generator 104 sets, in the respective subfields of the user information field, the parameters indicated by the RA resource information output from the RA resource controller 101.

[0045] For example, in a case where modified user information is applied, based on the RA resource information (RA-RU allocation) outputted from the RA resource controller 102, the start frame generator 104 sets the start RU position and the RU size of the RA-RU in the RU allocation subfield, and sets the number of contiguous RA-RUs in the SS allocation subfield. On the other hand, in the case where normal user information is used, based on the RA resource information (RA-RU allocation) issued from the RU resource controller 101, the start frame generator 104 sets the starting location and RU size of one RA-RU in the subfield allocation of RU.

[0046] Moreover, based on the information output from the AID controller 103 and the information output from the user information controller 102, the trigger frame generator 104 sets the AID corresponding to the format of the user information field in the AID12 subfield of the trigger frame.

[0047] The trigger frame generator 104 then outputs the generated trigger frame (trigger signal) to the transmit signal modulator 105 .

[0048] The transmit signal modulator 105 performs an encoding and modulation process on the start frame output from the start frame generator 104 . Moreover, the transmit signal modulator 105 adds control signals (also referred to as a preamble) to the modulated signal, such as a pilot signal used in frequency synchronization and timing synchronization at the receiving side (terminal 200), a channel estimation signal, and/or the like, thereby generating a radio frame (transmission signal), and the transmission signal modulator 105 outputs the resulting radio frame (transmission signal) to the radio transmitter/receiver 106.

[0049] The radio transmitter/receiver 106 performs a predetermined radio transmission process, including D/A (digital-to-analogue) conversion, up-conversion to a carrier frequency, and the like, on a radio frame (transmission signal) output from the modulator 105 of the transmission signal, and the radio transmitter/receiver 106 transmits the resulting signal, subjected to the radio transmission process, to the terminal 200 via the antenna 107. The radio transmitter/receiver 106 receives the signal transmitted from the terminal 200 via the antenna 107, and performs a predetermined radio reception process, including , baseband downconversion, A/D (analog-to-digital) conversion, and the like, on the received signal, and the radio transmitter/receiver 106 outputs the resulting signal subjected to the radio reception process to the receive signal demodulator 108 .

[0050] The receive signal demodulator 108 extracts the radio frame by performing autocorrelation processing or the like on the signal output from the radio transmitter/receiver 106, and outputs the extracted radio frame to the quality evaluator 109 .

[0051] The quality estimator 109 evaluates the reception quality of each RU with a predetermined size using the pilot signal included in the radio frame output from the receive signal demodulator 108, and outputs the result of the evaluation to the RA resource controller 101.

[0052] [Terminal Configuration]

Fig. 9 is a block diagram illustrating the configuration of a terminal 200 according to the present embodiment. Terminal 200 receives a trigger frame instructing RA transmission from AP 100, randomly selects one RU from the RA-RUs specified in the trigger frame, and transmits an RA signal to AP 100.

[0053] FIG. 9, terminal 200 includes an antenna 201, a radio transmitter/receiver 202, a receive demodulator 203, a start frame decoder 204, an AID controller 205, an RA resource determiner 206, an RA generator 207, and a transmit signal modulator 208. The radio transmitter/receiver 202 includes a transmitter and a receiver unit. The AID controller 205, the RA resource determiner 206, and the RA generator 207 collectively form an access controller (MAC).

[0054] The radio transmitter/receiver 202 receives the start frame instructing the transmission of the RA transmitted from the AP 100 via the antenna 201, and performs a predetermined radio reception process including baseband down-conversion, (analog-to-digital) conversion A /D, and/or the like, over the received signal, and the radio transmitter/receiver 202 outputs the resulting signal subjected to the radio reception process to the demodulator 203 of the receive signal. The radio transmitter/receiver 202 performs a predetermined radio transmission process, including D/A conversion, upconversion to a carrier frequency, and the like, on the transmission signal output from the transmission signal modulator 208 described later, and the radio transmitter/receiver 202 transmits the resulting signal, subjected to the radio transmission process, to the AP 100 via the antenna 201.

[0055] The receive signal demodulator 203 extracts a radio frame (start frame) by performing autocorrelation processing or the like on the signal output from the radio transmitter/receiver 202, and outputs the resulting extracted radio frame (start frame) to the start frame decoder 204.

[0056] The start frame decoder 204 detects the format of the user information field included in the start frame output from the receive signal demodulator 203, decodes the start frame, and provides the resulting decoded start frame to the RA resource determiner 206 .

[0057] The AID controller 205 operates in a manner similar to the AID controller 103 of the AP 100. More specifically, the AID controller 205 determines the AID (information described in the AID12 subfield of the starting frame) to set the format (modified user information or normal user information) of the information field about the user. The AID controller 205 outputs AID information indicating the determined AID to the RA resource determination block 206 . Details on defining an AID to format the user information field will be described later.

[0058] Based on the AID information output from the AID controller 205 and the information described in the start frame output from the start frame decoder 204, the RA resource determination unit 206 determines the RA-RU and control information for generating the RA signal. The RA resource determination unit 206 outputs certain control information for generating the RA-RU and the RA signal to the RA generator 207 .

[0059] More specifically, based on the AID information, the RA resource determination unit 206 identifies the format (modified user information or normal user information) of the user information field corresponding to the AID included in the AID12 subfield of the trigger frame output from the trigger frame decoder 204 .

[0060] In the case where the format of the user information field is the modified user information, the RA resource determination unit 206 identifies the starting location and size of the RUs of the RA-RUs from the RU allocation subfield, identifies the number of RA-RUs (number of contiguous RUs) from the subfield allocating an SS, applies the other parameters specified in the respective subfields of the modified user information field jointly to the RA-RU set, and determines the RA-RU by randomly selecting one from the RA-RU set.

[0061] On the other hand, in the case where the format of the user information field is normal user information, the RA resource determination unit 206 identifies the starting location and size of the RUs of one RA-RU from the RU allocation subfield, and separately applies other parameters specified in the respective subfields (including the allocation subfield SS) of the regular user information field, to one RA-RU.

[0062] Based on the control information for generating RA-RU and the RA signal output from the RA resource determination unit 206, the RA generator 207 generates an RA signal including a terminal identifier and information to transmit (data or control information, or the like) associated with the terminal 200 and outputs the resulting RA signal to the transmit signal modulator 208 .

[0063] The transmit signal modulator 208 performs coding/modulation on the RA signal. The transmit signal modulator 208 adds to a modulated control signal (preamble) such as a pilot signal used in frequency synchronization and timing synchronization in the AP 100, a channel estimation signal, and/or the like, thereby forming a radio frame (transmission signal) , and the transmit signal modulator 208 outputs the resulting radio frame (transmission signal) to the radio transmitter/receiver 202. Note that the RA signal is frequency mapped to RA-RU indicated by the information determined by the RA resource determination block 206 .

[0064] [AP 100 and terminal 200 operations]

The operations of the AP 100 and the terminal 200 according to the present embodiment are described in detail below.

[0065] The AP 100 (start frame generator 104) sets an unused AID in the AID12 subfield (terminal ID subfield) of the modified user information specifying one or more adjacent RA-RUs in the start frame, thereby notifying the terminal 200 that the user including an unused AID is the modified user information.

[0066] Note that the unused AID is the terminal specific AID for scheduled access (i.e., the scheduled AID assigned to terminal 200) (in the current 11ax specification, the unused AID is 0 or one of 2008 to 4094).

[0067] As described above, by setting, using an unused AID, that modified user information is to be applied, it is possible to set a plurality of RA-RUs using the modified user information in a small size trigger frame, meanwhile keeping the future extensibility of the trigger type (that is, without the new addition of trigger RA as one of the trigger types).

[0068] Specific examples 1 and 2 of methods for formatting a user information field using an unused AID are described below.

[0069] <Separate Example 1>

In separate example 1, only one unused AID is used to define RA-RU.

[0070] That is, the AID controller 103, 205 determines one unused AID to set the modified user information. For example, the AID controller 103, 205 determines that AID=0 as an unused AID to set a modified user ID. That is, the start frame generator 104 sets AID=0 (an unused AID) in the AID12 subfield, thereby informing the terminal 200 that the user information field including the AID12 subfield is in the modified user information format.

[0071] Note that in Specific Example 1, setting RA-RU using the normal user information is not performed. That is, in particular example 1, some RA-RU is given by the modified user information.

[0072] For example, the trigger frame generator 104 may set a plurality of modified user information items to enable setting parameters for respective modified user information items individually. That is, in Specific Example 1, a small size start frame including modified user information is used. This makes it possible to achieve a similar operation to allocate RA-RUs by ordinary user information (ie, setting on a per-RU basis). Note that, in particular example 1, when transmitting RA, the number of space division multiplexing layers is limited to 1 (no MIMO).

[0073] Particular Examples 1-1 and 1-2 of Particular Example 1 are described below for the case where the modified user information is set using one unused AID (AID=0).

[0074] <Separate example 1-1>

In a specific example 1-1, the start frame generator 104 in the AP 100 sets one modified user information in one start frame.

[0075] More precisely, as in the example shown in FIG. 10, the start frame generator 104 sets the AID in the AID12 subfield of one modified user information so that AID=0, which is an unused AID, thereby informing the terminal 200 that the user information field including this AID12 subfield is modified. user information.

[0076] That is, the start frame generator 104 sets the start RU location and RU size of the set of RA-RUs in the RU allocation subfield shown in FIG. 10 and sets, in the allocation subfield SS, not the number of space division multiplexed streams, but the number of contiguous RA-RUs. For example, in the case where the value received in the SS allocation subfield is 0 to 63 (6 bits), it is allowed to notify, using the SS allocation field, the number of contiguous RA-RUs in the range of 1 to 64. This makes it possible, for the AP 100 to set the terminal 200 to any one of the adjacent RUs including 1 to 64 RUs with one modified user information. In the example shown in FIG. 10, seven adjacent RA-RUs (adjacent RU=7) are defined by one modified user information.

[0077] In a separate example 1-1, as described above, all RA-RUs are set using one modified user information, and thus, a reduction in the size of the starting frame is achieved.

[0078] <Separate example 1-2>

In a separate example 1-2, the start frame generator 104 in the AP 100 sets a plurality of modified user information elements using a single start frame.

[0079] More precisely, as in the example shown in FIG. 11, the start frame generator 104 generates a start frame such that two modified user information fields are included in one start frame. As in the specific example 1-1, the start frame generator 104 sets AID=0, which is an unused AID, in the AID12 subfield of each modified user information field, thereby informing the terminal 200 that each user information field including the subfield AID12, is a modified user information.

[0080] FIG. 11, AP 100 specifies seven adjacent RA-RUs in the first modified user information, and specifies MCS #1 (eg, 16QAM) for these RUs. Moreover, AP 100 sets one RA-RU in the second modified user information and sets MCS #2 (eg, QPSK) for this RU.

[0081] In the case where there is overlap in RA-RU among the plurality of modified user information items, as in the example shown in FIG. 11 (in the example shown in FIG. 11, the RUs at the center of the seven RA-RUs are overlapped), the terminal RA resource determination unit 206 prioritizes the modified user information out of the plurality of modified user information items that specifies fewer contiguous RUs. That is, in FIG. 11, the modified user information specifying one RA-RU (adjacent RU=1) in the SS allocation is given priority, and thus MCS #2 is used for the central RU.

[0082] This makes it possible to use many different parameters for many RA-RUs given by one starting frame. Moreover, by setting the number of adjacent RUs specified by the modified user information to 1, it becomes possible to set the parameter individually for each RU. For example, in FIG. 11, in the central RU of the seven adjacent RA-RUs, a parameter (MCS) different from the parameters for other RUs is set. That is, in FIG. 11, out of seven adjacent RA-RUs, the same parameter (MCS) is set to six RUs, forming non-continuous bands other than the center RU.

[0083] For example, by setting a plurality of modified user information items in one start frame, it becomes possible for the AP 100 to establish a reliable MCS (e.g., QPSK) for a RU (e.g., a RU adjacent to a DC) from a plurality of contiguous RA-RUs , such as those shown in FIG. eleven.

[0084] In the separate example 1-2 as described above, it is possible to set a parameter (MCS, target RSSI, or the like) individually for each RA for the RA in a manner similar to the method by the ordinary user information, except that the multiplexing space division multiplexing is limited to level=1 of space division multiplexing (non-MIMO) for all RA-RUs.

[0085] Thus, according to the separate example 1-2, even in the case where the modified user information is used, it is possible to set a parameter individually for each RU, which makes it possible to use the parameter depending on the predicted performance of the RU, and thus throughput can be increased.

[0086] Moreover, in the specific example 1-2, by determining the rule regarding the priority applied when there is an overlap among the RUs defined by a plurality of modified user information items, the AP 100 is able to set a parameter depending on the predicted performance of the RUs by a start frame with a small size (with a small number of user information fields).

[0087] Note that the method of extracting RA-RU by a plurality of modified user information items included in one start frame is not limited to that shown in the example of FIG. eleven.

[0088] For example, as shown in FIG. 12, the AP 100 may define an RU with two modified user information items included in one start frame so that there is no overlap between the two modified user information items. In FIG. 12, AP 100 defines four RA-RUs by the first modified user information and defines MCS #1 (eg, 16QAM) for these RUs, and AP 100 defines, by the second modified user information, three RA-RUs in an area adjacent to the four RA-RUs given by the first modified user information (ie, so that there is no overlap in the area), and specifies MCS #2 (eg, QPSK) for these RUs.

[0089] As shown in FIG. 13, the AP 100 may define RUs with two modified user information items included in one start frame, so that the RUs specified by the respective modified user information items are located in areas separated from each other. In FIG. 13, the AP 100 specifies four RA-RUs by the first modified user information and three RA-RUs by the second modified user information, so that three RA-RUs are in an area separated from four RAs for the RAs specified by the first element of the modified information. about the user (and thus there was no overlap).

[0090] Although in FIG. 13 MCS #1 applies to RUs given by any modified user information, another parameter can be individually set by each modified user information. That is, the same parameter in terms of MCS or the like may be set for a plurality of modified user information items, or a different parameter may be set individually for each modified user information, as in FIG. 12. Moreover, as shown in FIG. 13, an arbitrary RU such as a scheduled access RU or a non-specified RU (non-dedicated RU) may be between two areas defined corresponding to two modified user information items. Note that, in the case where parameters in terms of coding type, MCS, and DCM are set jointly for all RUs defined by a plurality of user information items, there is a decrease in the degree of flexibility in performing the setting depending on the transmission characteristic, or the like, of each RU. However, in OFDMA-based random access, when the terminal acquires the right to transmit, one RU is randomly selected from all RA-RUs for random access. Therefore, if there is a difference in the amount of data that can be transmitted by an RU among the RUs specified in the modified user information item set, it is necessary to determine the data amount of a transmission frame after the terminal selects the RU, which increases the complexity of the transmission framing process. However, in the case where a common parameter is used for a plurality of modified user information items, the amount of data capable of being transmitted is equal to all random access RA-RUs, which makes it possible to simplify the transmission framing process performed at the terminal.

[0091] In the example described above with reference to FIG. 11 to 13, as an example, it is assumed that two modified user information items are included in one start frame. However, three or more modified user information items may be included in the start frame.

[0092] <Separate Example 2>

In separate example 2, a plurality of unused AIDs are used to define RA-RU.

[0093] That is, the AID controller 103, 205 determines a plurality of unused AIDs to define user information elements (modified user information or normal user information) indicating RA-RU.

[0094] The AID controller 103, 205 determines the user information elements specifying RA-RU, while distinguishing between an unused AID corresponding to the normal user information and an unused AID corresponding to the modified user information. For example, the AID controller 103, 205 defines AID=0 as an unused AID for setting normal user information and AID=2048 as an unused AID for identifying modified user information.

[0095] That is, the start frame generator 104 sets AID=0 in the AID12 subfield, thereby informing the terminal 200 that the user information field including the AID12 subfield is in the normal user information format and specifies one RA-RU . Moreover, the start frame generator 104 sets AID=2048 (an unused AID other than AID=0) in the AID12 subfield, thereby informing the terminal 200 that the user information field including the AID12 subfield is in the modified user information format. user, and specifies a set of RA-RUs (adjacent RA-RUs).

[0096] AID=2048 corresponds to a value that is set in the 12-bit AID12 subfield such that only the MSB (most significant bit) is set to 1 and the other 11 low order bits are all set to 0. Thus, in the case where AID set so that AID=0 or 2048 as described above, the terminal 200 determines that the user information for RA is set when the 11 low-order bits are all 0. That is, whether the modified user information or the normal user information is set, can only be determined from the MSB, and thus a simplification of the process performed by the terminal 200 is achieved.

[0097] In the example shown in FIG. 14, the start frame generator 104 in the AP 100 sets a set of unused AIDs (AID=0, 2048) so that AID=0 is set in the AID12 subfield of the normal user information, and AID=2048 is set in the AID12 subfield of each modified user information. Moreover, in FIG. 14, AP 100 defines three RA-RUs (adjacent RU=3) by each of the two modified user information elements, and defines MCS #1 (eg, 16QAM) for each of these RUs. AP 100 also defines one RA-RU with one normal user information and defines MCS #2 (eg, QPSK) for that RU.

[0098] This makes it possible to distinguishably use a plurality of different parameters for a plurality of RA-RUs given in one starting frame. It is also possible to set the parameter individually for each RU by making the setting such that the number of contiguous RUs=1 specified by the modified user information, or the parameter is set individually for each RU when the normal user information is used. For example, in FIG. 14, the central RU in seven adjacent RA-RUs is set with a parameter (MCS) different from the parameters set in other RUs. That is, in FIG. 14, out of seven adjacent RA-RUs, six RUs other than the center RU form a non-continuous band, and the same parameter (MCS) is set for these six RUs.

[0099] For example, the AP 100 is able to individually set a highly error-tolerant robust MCS for a portion of RUs (e.g., the central RU) that are predictably expected to encounter performance degradation using conventional user information or modified user information in which the number of contiguous RU is set to 1.

[0100] According to the specific example 2, as described above, it is possible to apply the parameter depending on the predicted performance for each RU by combining the normal user information and the modified user information, achieving throughput improvement. Moreover, according to Specific Example 2, the AP 100 is also able to define adjacent RA-RUs using modified user information as in Specific Example 1, thereby reducing the size of the start frame. Moreover, in particular example 2, it is also possible to set the number of space division multiplexed streams in the allocation subfield SS (that is, MIMO may be used) using normal user information.

[0101] Note that, in FIG. 14, as an example, AID=0 is set in the normal user information, and AID=2048 is set in the modified user information items. However, the values of the unused AIDs set in the normal user information and the modified user information are not limited to 0 and 2048, and a different value may be set.

[0102] Moreover, in Specific Example 2, the RA-RUs given in the same start frame need not be contiguous as in the example shown in FIG. 14, but RUs located in non-continuous areas separated from each other, for example, as in the example shown in FIG. fifteen.

[0103] Specific Example 2-1 and Specific Example 2-2 are described below, which are more detailed examples of Specific Example 2, of methods for specifying, using an unused identifier, that the user information field is normal user information or modified user information.

[0104] <Separate Example 2-1>

In a specific example 2-1, the start frame generator 104 in the AP 100 informs the terminal 200 of the RA-RU given by the normal user information (AID=0) and adjacent RA-RUs given by the modified user information (an unused AID with the value AID ≠ 0).

[0105] More precisely, as in the example shown in FIG. 16, the start frame generator 104 defines seven RA-RUs (adjacent RU=7) using modified user information (AID=2048) and defines MCS #1 (eg, 16QAM) for these RUs. Moreover, the start frame generator 104 defines one RA-RU using normal user information (AID=0) and defines MCS #2 (eg, QPSK) for that RU.

[0106] In the case where there is overlap between one RA-RU defined by the normal user information and adjacent RA-RUs defined by the modified user information, as shown in FIG. 16 (in FIG. 16, occurs in the central RU of seven RA-RUs), the RA resource determination unit 206 of the terminal 200 gives priority to the normal user information specifying the RU. That is, in FIG. 16, with regard to the central RU, normal user information is given priority, and thus MCS #2 is applied to the central RU.

[0107] Thus, in the specific example 2-1, as in the specific example 2 (FIG. 14), a plurality of parameters for RA-RU given in one start frame can be distinctly used. For example, as shown in FIG. 16, the AP 100 can set up a highly error-tolerant reliable MCS individually for a portion of RUs (eg, the central RU) that are predictably expected to experience performance degradation using normal user information.

[0108] In a specific example 2-1, by determining a rule indicating which RU is given priority in the case where there is an overlap between the RU specified by the normal user information and the RU specified by the modified user information, the AP 100 is able to set a parameter, dependent on predictive performance of the RU by means of a start frame with a small size (few user information fields). For example, in the separate example 2-1 (FIG. 16), it is possible to perform the RA-RU setup similar to the setting in the separate example 2 (FIG. 14) using a smaller start frame (with fewer user information fields).

[0109] <Separate example 2-2>

In a specific example 2-2, each of the plurality of unused AIDs is associated with a restriction condition (terminal restriction condition) imposed on the terminal 200 that transmits the RA signal. That is, the AP 100 sets, using the set of unused AIDs, a terminal constraint condition to be imposed on the terminal 200 that transmits the RA signal.

[0110] As in the example shown in FIG. 17, the AID controller 103, 205 determines AID=2008 and AID=2009 as unused AIDs corresponding to the elements of the modified user information specifying RA-RU. Moreover, the AID controller 103, 205 assigns different terminal restrictions to AID=2008 and AID=2009, respectively. The start frame generator 104 in the AP 100 sets AID=2008 or 2009 in the AID12 subfields, thereby informing the terminal 200 that the user information fields including the AID12 subfield are both in modified user information format.

[0111] In FIG. 17, the AP 100 sets the connection conditions of the terminal 200 as terminal restrictions different between the respective unused AIDs setting the modified user information. More precisely, as shown in FIG. 17, RA-RU specified by AID=2008 is RA-RU restricted for use between AP 100 and terminal 200 (associated STA) attached to AP 100. RA-RU specified by AID=2009 is RA-RU , restricted to use between AP 100 and non-associated terminal 200 (non-associated STA).

[0112] Thus, it is possible to classify terminals 200 transmitting an RA signal using each RU into associated STAs and non-associated STAs. Therefore, AP 100 sets the appropriate parameter individually for each connection condition of terminal 200.

[0113] For example, the AP 100 already has information regarding the associated STA (in terms of the communication condition of the terminal 200), and thus the AP 100 is able to properly adjust the uplink parameter (power, MCS, or the like) for the associated STA. In contrast, the AP 100 has no information regarding the unrelated STA, and thus the AP 100 sets a highly error-tolerant reliable value as an uplink parameter for the unrelated STA. Thus, as shown in FIG. 17, the AP 100 sets the RA-RU separately for each associated STA and non-associated STA, and performs scheduling so that OFDMA multiplexing does not occur in the same packet, thereby enabling, for example, to achieve interference reduction between terminals 200, for which different parameters are set (for example, transmission power). Moreover, the AP 100 can set an MCS with higher error tolerance for an unrelated STA, thereby preventing performance degradation.

[0114] In an alternative example, AP 100 may set a transmit power condition of terminal 200 as a terminal constraint that is different for each unused AID indicating modified user information (not illustrated in the figures). More specifically, the RA-RU given by AID=2008 is an RA-RU restricted for use by terminal 200 that has a minimum available power that is equal to or less than the required uplink transmit power, that is, that is capable of transmitting at the required uplink transmit power. The RA-RU given by AID=2009 is an RA-RU restricted to use by the terminal 200 that has a minimum available power that is greater than the required uplink transmit power, i.e., that is unable to transmit at the required uplink transmit power communication lines.

[0115] Thus, the AP 100 can perform scheduling so that OFDMA multiplexing is not performed in the same packet, in relation to the terminal 200, which is unable to transmit with the required uplink transmission power, and the terminal 200, which is capable of transmit with the required uplink transmission power, thereby achieving interference reduction between the terminals 200. The AP 100 may set an MCS with higher error resilience to the terminal 200 that is unable to transmit with the required uplink transmission power, thereby preventing performance degradation.

[0116] In an alternative example, as a terminal constraint different for each unused AID specifying modified user information, AP 100 may set a transmission data constraint (not illustrated) imposed on terminal 200. More specifically, AID=2008 may set modified user information including trigger-dependent user information information in the user information field, meanwhile, AID=2009 can set modified user information not including trigger-dependent user information information .

[0117] In the case where the user information field includes information on trigger-dependent user information (that is, in the case where an A-MPDU (MAC aggregate data unit) which is a combination of a plurality of MPDUs) is used), the time of the process running on the AP 100 is predicted to be longer than when there is no trigger-dependent user information information. In view of the above, the AP 100, for example, can perform scheduling so that the RU used by the terminal 200 is selected depending on the processing time for an uplink signal that is transmitted in response to an instruction from a start frame, thereby RU.

[0118] Note that the terminal restriction conditions are not limited to the connection condition of the terminal 200, the transmission power condition, and the transmission data restriction condition described above.

[0119] According to the specific example 2-2, as described above, by issuing an instruction in which a plurality of unused AIDs is associated with the restrictive conditions imposed on the terminal 200, the AP 100 is able to properly perform RA-RU scheduling depending on the state of the terminal 200 .

[0120] Note that, in the specific example 2-2, RA-RUs defined by one start frame are not limited to adjacent RUs such as those shown in FIG. 17. For example, RUs located in non-continuous areas separated from each other may be defined as shown in FIG. eighteen.

[0121] Separate examples 1 and 2 of methods for formatting a user information field using an unused AID have been described above.

[0122] In the examples described above, the parameter specified by the modified user information. as an example, is MCS. However, other parameters (coding type, DCM, target RSSI) may also be set in a similar manner to the MCS.

[0123] [Useful results]

According to the present embodiment, as described above, the start frame generator 104 from the AP 100 sets an unused AID that should not be used in scheduled access in the modified user information, specifying one or more contiguous random access resource blocks in the start frame. This enables the terminal 200 to decide, based on the AID value indicated in the AID12 subfield of each user information field of the starting frame, whether or not the user information field is modified user information.

[0124] According to the present embodiment, therefore, it is not necessary to use (waste) the trigger type reserved area to set the modified user information. That is, you can specify modified user information, meanwhile, leaving room for future expansion of the standard. Thus, according to the present embodiment, it is possible to appropriately set the modified user information in the start frame.

[0125] Moreover, according to the present embodiment, by setting a plurality of modified user information items (or normal user information and at least one modified user information) in one start frame, it becomes possible to allocate not only contiguous RUs, but also non-contiguous RUs, and it also becomes possible to set different parameters for the respective user information items. This makes it possible to set a parameter depending on the predicted performance for each of the plurality of RA-RUs defined by the start frame, thereby achieving improved throughput.

[0126] (Second embodiment)

For example, in the case where the modified user information is set as described above with reference to FIG. 6A or other figures, it is discussed to reduce the size of the trigger by removing the trigger dependent general information subfield and the trigger dependent user information subfield.

[0127] However, in the case where the trigger type is the basic trigger (see FIG. 3) (in the case where the trigger frame dictates normal data transmission without imposing any restrictions on the uplink signal format), not only when the access, but also when transmitting RA, it is useful that the user information field includes a trigger-dependent user information subfield, thereby providing a notification of restrictive information (restriction on the number of combined MPDUs recommended by AC, or the like) on uplink transmission data shown in FIG. 5.

[0128] In view of the above, the second embodiment provides a method for efficiently transmitting restrictive information on uplink transmission data when modified user information is transmitted.

[0129] According to the present embodiment, the wireless communication system includes an AP 300 (radio transmission device) and a terminal 400 (radio receiver). The AP 300 transmits a start frame specifying the transmission of the RA to the terminal 400. The terminal 400 receives the start frame and sends the RA to the AP 300 using the resource specified in the start frame.

[0130] [AP Configuration]

Fig. 19 is a block diagram illustrating the configuration of the AP 300 according to the present embodiment. In FIG. 19, like blocks operating in a similar manner to the blocks according to the first embodiment (FIG. 8) are marked with like reference characters, and their description is omitted. More specifically, the AP 300 is different from the AP 100 (FIG. 8) according to the first embodiment in that the trigger dependent information controller 301 is additionally provided and the trigger frame generator 302 functions differently.

[0131] The trigger dependent information controller 301 determines trigger dependent information (trigger dependent general information or trigger dependent user information) depending on the trigger type, and outputs trigger dependent information (restrictive information on data uplink transmission) and information indicating the field and subfield in which the trigger dependent information is located to the trigger frame generator 302 .

[0132] The location of the trigger-dependent information in the trigger frame, for example, is determined by specifications and the like, and the location is equally recognized by both the transmitter and the receiver (AP 300 and terminal 400). For example, in the case where the trigger type is a basic trigger and the format of the user information field is modified user information, restrictive information on uplink transmission data is included as trigger-dependent information in the trigger frame. Later, a method for applying trigger dependent information to terminal 400 will be described.

[0133] The trigger frame generator 302, in addition to the operation performed by the trigger frame generator 104 according to the first embodiment, performs the operation of setting the trigger dependent information in a predetermined field and subfield of the trigger frame according to the instruction issued by the trigger dependent information controller 302 .

[0134] [Terminal Configuration]

Fig. 20 is a block diagram illustrating the configuration of a terminal 400 according to the present embodiment. In FIG. 20, like blocks operating in a similar manner to the blocks according to the first embodiment (FIG. 9) are indicated with like reference symbols, and their description is omitted. More specifically, the terminal 400 is different from the terminal 200 (FIG. 9) according to the first embodiment in that the trigger dependent information data acquisition unit 401 is additionally provided, and the RA generator 402 functions differently.

[0135] The trigger-dependent information acquisition unit 401 acquires trigger-dependent information (trigger-dependent general information or trigger-dependent user information) from the trigger frame output from the trigger frame decoder 204, and outputs the collected trigger-dependent information. trigger information to the 402 RA generator.

[0136] Based on the RA-RU and the control information for generating the RA signal determined by the RA resource determination block 206 and the trigger dependent information outputted from the trigger dependent information data acquisition block 401, the RA generator 402 generates an RA signal including including a terminal identifier and transmission information (data, control information, or the like) associated with the terminal 400.

[0137] [AP 300 and terminal 400 operations]

Next, the operations of the AP 300 and the terminal 400 according to the present embodiment are described.

[0138] In the case where the trigger type is a basic trigger, the AP 300 sets the restriction information on the uplink transmission data as the trigger dependent information even when the format of the user information field is the modified user information.

[0139] Specific Examples 1 to 3 of methods for specifying restrictive information on uplink transmission data in a start frame including modified user information are described below.

[0140] <Separate Example 1>

As illustrated in FIG. 6A, in a trigger frame in which the modified user information does not include a trigger-dependent user information subfield when the trigger type is a basic trigger, so that the terminal 400 detects the size of each user information field in the trigger frame ( in order to detect the boundary between each user information field), it is necessary to decode the AID12 subfield of each user information field, resulting in an increase in the complexity of the receiving process performed by the terminal 400.

[0141] In view of the above, in Specific Example 1, in the case where the trigger type is a basic trigger, the modified user information is configured such that the trigger-dependent user information subfield is also included in the modified user information, and the limit information on the uplink data is set as trigger dependent information.

[0142] That is, in the case where the trigger type of the trigger frame is the basic trigger, the trigger frame generator 302 of the AP 300 sets the restriction information on the uplink signal when transmitted in the modified user information.

[0143] More precisely, in the example shown in FIG. 21, the start frame includes a mixture of ordinary user information elements (AID=1 and 2) specifying an RU for scheduled access and modified user information elements (AID=0) specifying a plurality of RA-RUs. Moreover, in FIG. 21, the basic trigger is set in the trigger type subfield of the general information field.

[0144] In this case, in each normal user information, the restriction information on uplink transmission data specific to each terminal is set as trigger-dependent user information. On the other hand, in each modified user information, only in the case where the basic trigger is set as the trigger type, the restriction information on the uplink transmission data to be applied to the RA-RU is set as trigger-dependent user information signal.

[0145] Thus, in the case where the type of trigger included in the general information of the trigger frame is the basic trigger, it can be determined that all user information fields have sizes (for example, 5 bytes), including trigger-dependent information about the user, that is, they have the same size. That is, the terminal 400 does not need to decode the AID12 subfield of each user information field to determine the size of the user information field.

[0146] According to Specific Example 1, as described above, the size of the user information field is uniquely determined by the type of trigger regardless of the format of the user information field, and thus simplification of the reception process performed by the terminal 400 is achieved.

[0147] Moreover, the AP 300 can announce information about the trigger-dependent user information even in the modified user information. In addition, when the terminal 400 transmits an RA, the data transmission restriction information can be effectively used, as in the transmission of scheduled access.

[0148] <Separate example 2>

In Specific Example 2, in the case where the trigger type of the trigger frame is a basic trigger, the uplink signal transmission restriction is imposed on the terminal 400, which is directed to use one or more adjacent RA-RUs specified by the modified user information in the trigger. frame.

[0149] That is, in the separate example 2, as in the example shown in FIG. 22, in the case where the trigger type is a basic trigger, unlike the separate example 1 (FIG. 21), any user information does not include a trigger-dependent user information subfield.

[0150] With regard to the constant limit imposed on the uplink data transmitted by the terminal 400, for example, the MU MPDU duty cycle and the TID aggregation limit may be limited to constant values (a single MPDU with a small size) provided that the number of MPDUs=1. This makes it possible to prevent the AP 300 from experiencing a delay during a response. Note that the constant limit on uplink data transmitted by the terminal 400 is not limited to a constant value as long as the number of MPDUs=1, but other values may be applied.

[0151] Thus, in Specific Example 2, when the trigger type is a basic trigger, by specifying a plurality of RA-RUs using the modified user information as in the first embodiment, it is possible to impose a restriction on RA transmission using RA-RUs. given by the modified user information, meanwhile reducing the start frame size.

[0152] <Separate example 3>

In Specific Example 3, in the case where the trigger type is the basic trigger, as shown in FIG. 23, the common information includes a trigger-dependent common information subfield, and the data transmission restriction information is set by a parameter that is common to all OFDM multiplexed terminals 400.

[0153] That is, in the case where the trigger type of the trigger frame is the basic trigger, the trigger frame generator 302 of the AP 300 sets the restriction information on transmission of the uplink signal in the common information.

[0154] That is, in Specific Example 3, in the user information field, the restriction information on the uplink signal in transmission is not set regardless of the format of the user information field (modified user information or normal user information). Therefore, as shown in FIG. 23, even in the case where the trigger type is a basic trigger, the trigger-dependent user information subfield is not included in either the modified user information or the normal user information.

[0155] Setting the restriction information in the common information causes the data transmission restriction condition to be the same for all OFDM-multiplexed terminals 400. However, the user information does not include the trigger-dependent user information subfield, and thus a reduction in size is achieved. starting frame.

[0156] In Specific Example 3, regardless of the format of the user information field, the user information does not include a trigger-dependent user information field, and thus the size of the user information fields is uniquely determined by the trigger type, as in the separate example 1. Therefore, it becomes unnecessary for the terminal 400 to decode the AID12 subfield of each user information field to detect the size of the user information field, and thus, the reception process performed by the terminal 400 is simplified.

[0157] Specific Examples 1 to 3 of Methods for Setting Restriction Information on Uplink Transmission Data in a Start Frame Including Modified User Information as Described Above.

[0158] In FIG. 21 to 23, RA-RUs given by one start frame are contiguous RUs as an example. However, RA-RUs are not limited to adjacent RUs. RUs located in non-continuous areas separated from each other (not shown) may be defined by one start frame, as in the first embodiment (eg, Fig. 13, Fig. 15 and Fig. 18).

[0159] Moreover, the above-described operations according to the present embodiment are not limited to the case where the trigger type is the basic trigger. For example, when the trigger type enables RA transmission, and the trigger type includes trigger-dependent user information, operations according to the present embodiment are possible in the same manner as described above, and similar results can be achieved.

[0160] Embodiments of the present invention have been described above.

[0161] (Other embodiments)

(1) As shown in FIG. 24, one start frame may include a mixture of setting an RA-RU using the modified user information or conventional user information described above with reference to the embodiments and setting a scheduled access RU.

[0162] (2) In the embodiments described above, methods for setting modified user information using an unused AID have been explained. Instead of the unused AID, the modified user information may be specified using a reserved area (1 bit) in the user information field. For example, one bit in the reserved area may be used to specify the format of the user information field indicating whether the format is modified user information or normal user information. Alternatively, the modified user information may be specified using a different subfield in the user information field. For example, AID=0 may specify RA-RU, and without disabling DCM in RA-RU, one DCM bit may be used to specify a format to indicate whether the format is modified user information or normal user information.

[0163] (3) When RA-RU is specified, predetermination may be made as to the order, in the start frame, of notification of the normal user information (specified by AID=0) and the modified user information (specified by the used AID with AID value ≠ 0 ). This makes it possible to achieve simplification of the reception process performed by the terminal.

[0164] In the specification, in order to simplify the reception process at the terminal, the notification order is defined to give the user information in the start frame, the RU notification of the scheduled access, and then, the RA-RU notification is given. In the case where RA-RU notifications are given by a mixture of normal user information and modified user information, as in the present embodiment, predetermining the notification order of these user information items makes it possible to simplify the reception process at the terminal.

[0165] For example, as shown in FIG. 25, the notification order may be predetermined such that the notification should be issued in the order of "Scheduled access RU notification (in the example shown in FIG. 25, user information items individually specifying terminals with AID=1, 2)", " RA-RU notifications using modified user information (in the example shown in FIG. 25 specified by AID=2048)" and "RA-RU notifications using normal user information (in the example shown in FIG. 25 given by AID=0)". By predetermining the notification order as described above, when there is overlap between given RA-RUs, as in the embodiments described above (for example, see FIG. 16), the receiving process at the terminal can be simplified, for example, so that the instruction in the modified user information was overwritten with normal user information.

[0166] Moreover, the notification order of the plurality of modified user information items included in one start frame can be predetermined so that notification is issued in descending order of the number of contiguous RUs given by the modified user information items. By predetermining the notification order as described above, when there is overlap between given RA-RUs, as in the embodiments described above (for example, see FIG. 11), the receiving process at the terminal can be simplified, for example, so that the modified information about a user specifying a large number of adjacent RUs was overwritten with modified user information specifying a small number of adjacent RUs.

[0167] (4) The present invention may be implemented in software, hardware, or software in combination with hardware. Each functional block described in the embodiments may be partially or completely implemented by an LSI, which is an integrated circuit. Each process described in the embodiments may be partially or completely controlled by a single LSI or a combination of LSIs. One LSI can be implemented by one microcircuit. One chip may include some or all of the functional blocks. Each LSI may include an LSI data input and output, also may be referred to as an IC (Integrated Circuit, IC), system LSI, super LSI or ultra LSI depending on the density of integration. The implementation method of the integrated circuit is not limited to the LSI, but the integrated circuit may be implemented as a dedicated circuit or a general purpose processor. An integrated circuit may also be implemented using an FPGA (field-programmable gate array) that can be programmed after the LSI is released, or a reconfigurable processor that is allowed to be reconfigured in terms of connecting or adjusting circuit cells within the LSI. The present invention may be implemented through digital or analog processing. When a new integrated circuit technology other than LSI technologies is realized in the future due to advances in semiconductor technology or a related technology, functional blocks can be implemented using such new technology. Potentially possible use of biotechnology.

[0168] The communication apparatus of the present invention includes a trigger generator that generates a trigger signal instructing transmissions of an uplink signal, wherein, in the case where the trigger signal includes a first terminal information field specifying one or more adjacent blocks of random access resource blocks, an unused identifier not to be used as a terminal identifier is set in the terminal identifier subfield of the first terminal information field, and a transmitter that transmits the generated trigger.

[0169] In the communication device according to the present invention, when a random access resource block is set, one unused identifier value is set in the terminal identifier subfield.

[0170] In the communication apparatus of the present invention, in the case where the trigger signal includes a plurality of first terminal information fields, when there is an overlap in one or more adjacent random access resource blocks specified respectively by the first terminal information fields, the priority of the set of the first terminal information fields for overlapping resource blocks is determined such that priority is given to the instruction described in the first terminal information field specifying a smaller number of resource blocks.

[0171] In the communication device according to the present invention, when a random access resource block is set, there are a plurality of unused identifier values that can be set in the terminal identifier subfield.

[0172] In the communication device according to the present invention, the trigger generator sets the first unused identifier value of the plurality of unused identifier values in the terminal identifier subfield of the first terminal information field, and sets the second unused identifier value in the terminal identifier subfield of the second terminal information field, specifying one resource block for random access. In the case where there is an overlap between the resource block specified by the first terminal information field and the resource block specified by the second terminal information field, the priority in the overlapping resource block is determined to give priority to the instruction indicated in the second terminal information field.

[0173] In the communication device according to the present invention, each of the unused identifiers is associated with a restrictive condition imposed on a terminal that transmits a random access signal.

[0174] In the communication apparatus of the present invention, in the case where the trigger is of a type that does not impose restrictions on the uplink signal format, the trigger generator sets information in the first terminal information field to set the restriction on the uplink signal during transmission.

[0175] In the communication device according to the present invention, in the case where the trigger signal is of a type that does not impose restrictions on the format of the uplink signal, the restriction on the uplink signal in transmission is imposed on the terminal assigned to use one or more contiguous blocks random access resources specified by the first trigger terminal information field.

[0176] In the communication device according to the present invention, in the case where the trigger is of a type that does not impose restrictions on the uplink signal format, the trigger generator sets information indicating the restriction on the uplink signal in transmission, not in the first field terminal information, but in a general information field including information common to terminals.

[0177] The communication method according to the present invention includes generating a trigger instructing transmission of an uplink signal. In the case where the trigger includes a first terminal information field specifying one or more contiguous random access resource blocks, an unused identifier not used as a terminal identifier is set in the terminal identifier subfield of the first terminal information field, and generated start signal is transmitted.

[0178] Industrial Applicability

An aspect of the present invention is useful for efficient use of spare fields or for reducing spare fields.

[0179] List of reference symbols

100, 300AP

101 RA resource controller

102 user information controller

103, 205 AID controller

104, 302 start frame generator

105, 208 transmit signal modulator

106, 202 radio transmitter/receiver

107, 201 antenna

108, 203 receive signal demodulator

109 quality assessment block

200, 400 terminal

204 start frame decoder

206 RA resource definition block

207, 402 generator RA

301 trigger dependent information controller

401 Trigger-dependent Data Acquisition

Statement 1. A communication device, comprising:

a trigger generator that generates a trigger indicating transmission of an uplink signal, wherein the trigger includes a terminal information field that includes a terminal identifier (ID) subfield and a resource block allocation information subfield, wherein, in when the trigger includes a first terminal information field specifying one or more contiguous random access resource blocks, an unused identifier that cannot be used as a terminal identifier is set in a terminal identifier subfield of the first terminal information field; and

a transmitter that transmits the generated start signal.

Statement 2: The communication device according to Statement 1, wherein in the case where the trigger includes a terminal information field specifying two or more adjacent random access resource blocks, the resource block allocation information subfield of the terminal information field indicates the location of the start a resource block of the two or more contiguous random access resource blocks, and the terminal information field further includes an additional subfield indicating the number of contiguous random access resource blocks.

Statement 3: The communication device according to Statement 1, wherein in the case where the trigger signal includes the first terminal information field and the second terminal information field specifying one resource block, and the one resource block specified by the second terminal information field, included in said one or more contiguous random access resource blocks, that one resource block is excluded from the random access resource blocks.

Statement 4: The communication device according to Statement 1, wherein there are a plurality of unused identifiers, including a first unused identifier and a second unused identifier.

Statement 5: The communication device according to Statement 4, wherein the trigger generator sets the first unused identifier in the terminal identifier subfield of the first terminal information field, and sets the second unused identifier in the terminal identifier subfield of the second terminal information field specifying one resource block , and

in the case where there is an overlap between said one or more adjacent random access resource blocks specified by the first terminal information field and said one resource block specified by the second terminal information field, the overlapping one resource block is excluded from the random access resource blocks.

Statement 6: The communication device according to Statement 4, wherein each of the unused identifiers is associated with a restriction condition imposed on the terminal that transmits the random access signal.

Statement 7: The communication device according to Statement 6, wherein the first unused identifier indicates that the terminal which transmits the random access signal is restricted to the terminal associated with the communication device, and the second unused identifier indicates that the terminal which transmits the random access signal is restricted to the terminal , not associated with a communication device.

Statement 8: The communication apparatus according to Statement 1, wherein the trigger generator sets, in the first terminal information field, information that indicates a limit on the uplink signal in transmission.

Statement 9: The communication device according to Statement 1, wherein the uplink signal restriction in transmission is imposed on a terminal assigned to use the one or more contiguous random access resource blocks specified by the first trigger terminal information field.

Statement 10: The communication apparatus according to Statement 1, in which the trigger generator sets information indicating a limit on the uplink signal in transmission, not in the first terminal information field, but in a common information field including information common among terminals.

Statement 11. A method of communication, comprising the steps in which:

generating a trigger indicating transmission of an uplink signal, wherein the trigger includes a common information field and a terminal information field, the common information field includes a trigger type subfield indicating the trigger type, the terminal information field includes a terminal identifier subfield and a resource block allocation information subfield, wherein in the case where the trigger includes a first terminal information field specifying one or more contiguous random access resource blocks, an unused identifier that cannot be used as an identifier terminal is set in the terminal ID subfield of the first terminal information field; and

transmit the generated start signal.

Claims (14)

1. Communication device, comprising: a receiver that, in operation, receives a trigger frame comprising a first user information field and a second user information field, wherein the first user information field contains a first terminal identifier (ID) subfield and a first resource block (RU) allocation subfield, and the second user information field contains a second a terminal ID subfield and a second RU allocation subfield, wherein a value not to be used for the terminal ID is set to the first random access terminal ID subfield, the first RU allocation subfield indicates the starting RU of one or more adjacent random access (RA-RU) RUs and the first user information field further comprises a first RA-RU number subfield indicating a first number of RUs in said one or more adjacent RA-RUs; and a transmitter that, in operation, transmits an uplink signal using at least one of said one or more adjacent RA-RUs. 2. The communication device according to claim 1, wherein the first set of adjacent RA-RUs that are allocated by the first user information field does not overlap with the second set of adjacent RA-RUs that are allocated by the second user information field. 3. The communication device of claim 1, wherein the second user information field indicates an RU, and in the case where the RU indicated by the second user information field is included in said one or more adjacent RA-RUs, said RU is excluded from the potentially eligible RAs -RU. 4. The communication device according to claim 1, wherein the coding type and the modulation and coding scheme (MCS) are configured separately for the first set of adjacent RA-RUs that are allocated by the first user information field and the second set of adjacent RA-RUs that are allocated through the second user information field. 5. The communication device according to claim 1, wherein the first value is set to the first subfield of the terminal ID for a terminal that is associated with said communication device, and the second value is set to the second subfield of the terminal ID for another terminal that is not associated with said communication device, where the second value is different from the first value. 6. The communication device according to claim 1, wherein the restriction condition regarding the terminal that transmits the random access signal is associated with each of the first value and the second value. 7. The communication device according to claim 1, wherein the restriction information is set in the first user information field, the restriction information indicating a restriction regarding transmission of the uplink signal. 8. The communication device of claim 7, wherein said limitation applies to a terminal to which said one or more adjacent RA-RUs are indicated by using the first user information field. 9. The communication device according to claim 1, wherein the restriction information is set in a common information field for carrying control information common to a plurality of terminals, the restriction information indicating a restriction regarding transmission of an uplink signal. 10. Method of communication, containing the steps in which: a start frame is received comprising a first user information field and a second user information field, the first user information field comprising a first terminal ID subfield and a first resource block (RU) allocation subfield, and the second user information field comprising a second terminal ID subfield and a second RU allocation subfield , wherein the value not to be used for the terminal ID is set to the first subfield of the random access terminal ID, the first RU assignment subfield indicates the starting RU of one or more adjacent random access RUs (RA-RU), and the first user information field further contains the first an RA-RU count subfield indicating the first number of RUs in said one or more adjacent RA-RUs; and transmitting the uplink signal using at least one of said one or more adjacent RA-RUs.

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