Access point, terminal and communication method

Abstract

An access point includes: a control circuit that generates control information relating to a resource used for transmission of a second signal occurring during a transmission period of a first signal; and a transmission circuit that transmits the control information.

Description

Technical Field

[0001] The present disclosure relates to an access point, a terminal and a communication method. Background Art

[0002] The Institute of Electrical and Electronics Engineers (IEEE) is studying the IEEE 802.11be (hereinafter referred to as "11be") standard for the next generation wireless local area network (LAN), which is a successor standard equivalent to the IEEE 802.11ax (hereinafter referred to as "11ax") standard. For example, 11ax is also called "High Efficiency (HE)" and 11be is also called "Extreme High Throughput (EHT)". In addition, the required specifications related to the successor standard of 11be aimed at further reducing latency (Low latency) or improving throughput are also being studied (for example, refer to non-patent document 1). For example, the successor standard of 11be is also called "EHT enhancement (EHTplus)" or "enhanced 11be (beyond 11be)".

[0003] Prior art literature

[0004] Non-patent literature

[0005] Non-patent document 1: IEEE P802.11-22 / 0032r0, “Thoughts on Next Generation After802.11be”

[0006] Non-patent document 2: IEEE 802.11-21 / 1333r4, “CC36 CR for Trigger frame on Common Info field format”

[0007] Non-patent document 3: IEEE 802.11-21 / 0259r4, “Proposed Draft Specification for Trigger frame for EHT”

[0008] Non-patent document 4: IEEE P802.11ax / D8.0

[0009] Non-Patent Document 5: IEEE 802.11-21 / 1852r1, “Overlaid UL transmissions enabling low latency for emergency use cases” Summary of the invention

[0010] However, methods for controlling signal transmission in wireless communications such as wireless LANs have not yet been fully studied.

[0011] The non-limiting embodiments of the present disclosure contribute to providing an access point, a terminal, and a communication method that can improve the efficiency of transmission control in wireless communications.

[0012] An access point according to an embodiment of the present disclosure includes: a control circuit that generates control information related to resources used for transmission of a second signal that occurs during a transmission period of a first signal; and a transmission circuit that transmits the control information.

[0013] It should be noted that these general or specific aspects may be implemented by a system, an apparatus, a method, an integrated circuit, a computer program or a recording medium, or may be implemented by any combination of systems, apparatuses, methods, integrated circuits, computer programs and recording media.

[0014] According to an embodiment of the present disclosure, for example, the efficiency of transmission control in wireless communication can be improved.

[0015] More advantages and effects of an embodiment of the present disclosure will be explained through the description and drawings. These advantages and / or effects are provided by several embodiments, and the features described in the description and drawings, but not necessarily all of them need to be provided in order to obtain one or more of the same features. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a diagram showing an example of the format of an extremely high throughput trigger-based physical layer protocol data unit (EHT TB PPDU: Extreme High Throughput (EHT) Trigger-based (TB) Physical layer (PHY) Protocol Data Unit (PPDU)).

[0017] Figure 2 This is a diagram showing an example of a common information field (Common Info field).

[0018] Figure 3 This is a diagram showing an example of a user information field (User Info field).

[0019] Figure 4 This is a diagram showing an example of a special user information field (Special User Info field).

[0020] Figure 5 This is a diagram showing an example of a trigger type (Trigger type).

[0021] Figure 6 This is a diagram showing an example of data transmission.

[0022] Figure 7 This is a diagram showing an example of transmitting uplink data overlaying other data.

[0023] Figure 8 This is a diagram showing an example of pre-emption transmission.

[0024] Fig. 9 This is a block diagram showing a configuration example of a part of an access point (AP: Access Point).

[0025] Fig.10 This is a block diagram showing a configuration example of a part of a terminal (STA: Station).

[0026] Fig.11 This is a block diagram showing a structural example of an AP.

[0027] Fig.12 This is a block diagram showing a structural example of a terminal.

[0028] Fig.13 This is a diagram showing an example of a transmission condition based on the length (LENGTH).

[0029] Fig.14 This is a diagram showing an example of a transmission condition based on the transmission timing.

[0030] Fig.15 This is a diagram showing an example of the timing of preemptive transmission.

[0031] Fig.16 This is a diagram showing an example of a trigger dependent user information field (Trigger Dependent User info field).

[0032] Fig.17 This is a diagram showing an example format of a user information field.

[0033] Fig.18 This is a diagram showing an example format of a user information field.

[0034] Fig.19 This is a diagram showing an example format of a user information field.

[0035] Fig. 20 This is a diagram showing an example of preemptive transmission.

[0036] Fig.21 This is a diagram showing an example of preemptive transmission.

[0037] Fig. 22 This is a diagram showing an example of preemptive transmission.

[0038] Fig.23 This is a diagram showing an example of preemptive transmission.

[0039] Fig.24 This is a diagram showing an example of preemptive transmission.

[0040] Fig.25 This is a diagram showing an example of the format of an EHT multi-user PPDU (ETH MU PPDU: EHT multi-user (MU) PPDU).

[0041] Fig.26 This is a block diagram showing a structural example of an AP.

[0042] Fig. 27 This is a block diagram showing a structural example of a terminal.

[0043] Fig.28 This is a diagram showing an example format of a pre-emption indicator.

[0044] Fig.29 This is a diagram showing an example format of a preemption identifier.

[0045] Fig.30 This is a diagram showing an example format of a PPDU including a preemption identifier.

[0046] Fig.31 This is a diagram showing an example format of a PPDU including a preemption identifier. DETAILED DESCRIPTION

[0047] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings.

[0048] In HE, the introduction of uplink Orthogonal Frequency-Division Multiple Access (OFDMA) is specified. An access point (AP: Access Point. Or, also called "base station") sends a control signal (hereinafter referred to as "trigger frame") instructing the transmission of an uplink OFDMA signal to multiple terminals (STA: Station. Or, also called "non-AP STA") accommodated by the AP.

[0049] The terminal sends an uplink OFDMA signal based on the information indicated by the trigger frame. Figure 1 This is a diagram showing an example of the format of a trigger-based physical layer (PHY) protocol data unit (TB PPDU) used in an uplink OFDMA signal. Figure 1 In the OFDM, the legacy short training field (L-STF: Legacy Short Training Field) / legacy long training field (L-LTF: Legacy Long Training Field) / legacy signal (L-SIG: Legacy Signal) / repeated legacy signal (RL-SIG: Repeated Legacy Signal) / universal signal (U-SIG: Universal Signal) is an OFDM field that applies the same Fast Fourier Transform (FFT: Fast Fourier Transform) or Discrete Fourier Transform (DFT: Discrete Fourier Transform) (hereinafter referred to as "FFT / DFT") size as the legacy version (for example, IEEE802.11a or IEEE802.11n, etc.), and / or the same subcarrier spacing as the legacy version, and is also called "pre-EHT modulated field (pre-EHT modulated field)", "legacy preamble" or "legacy field". In addition, in Figure 1 In the present invention, the field after EHT-STF is an OFDM field that applies the FFT / DFT size specified in EHT and / or the subcarrier spacing specified in EHT, also known as the "EHT modulated field" or "non-legacy field".

[0050] In the EHT enhancement, a new TB PPDU format may be specified. The new TB PPDU format may also include a non-legacy STF (equivalent to Figure 1EHT-STF), non-old version LTF (equivalent to Figure 1 EHT-LTE).

[0051] In EHT, it is also agreed to reuse the HE trigger frame as a control signal for instructing a plurality of terminals to transmit uplink OFDMA signals (for example, refer to Non-Patent Document 2).

[0052] In the EHT enhancement, it is also possible to reuse the trigger frame as a control signal instructing multiple terminals to send uplink signals.

[0053] For example, in addition to a medium access control (MAC) header, the trigger frame also includes a general information field, a user information list (User Info List) and a special user information field (for example, refer to non-patent documents 2 and 3). In the general information field, for example, for multiple terminals performing OFDMA multiplexing, information common to the terminals is included. The user information list, for example, includes multiple user information fields. The user information field includes inherent information dedicated to the terminal. The special user information field includes general information sent to the terminal corresponding to EHT (for example, called "EHT terminal"). In addition, the special user information field may also include general information sent to the terminal corresponding to EHT enhancement (for example, called "EHT enhanced terminal").

[0054] Figure 2 This is a diagram showing an example of a Common Info field (EHT variant). Figure 3 This is a diagram showing an example of a user information field (User Info field, EHT variant). Figure 4 This is a diagram showing an example of a special user information field. Figure 2 , Figure 3 and Figure 4 The following shows a structural example that is currently being studied in EHT (for example, refer to non-patent documents 2 and 3).

[0055] When sending a trigger frame to an EHT terminal, a special user information field may also be set. For example, the special user information field is a field in which the user information field is set to a special AID (Association ID, such as AID=2007). The special user information field can notify information that is common between terminals, such as uplink bandwidth information sent to the EHT terminal. In EHT enhancement, similar to EHT, a special AID (for example, AID=2006) for the EHT enhanced terminal can be used, and information that is common between EHT enhanced terminals can be notified in the special user information field.

[0056] The trigger type subfield of the general information field includes information indicating the type of the trigger frame. The type of the trigger frame may be the type of the signal that the AP causes the terminal to send.

[0057] Figure 5 is a diagram showing an example of a trigger type. Figure 5 In HE, the correspondence between the value of the trigger type subfield and the type of trigger frame indicated by the value is shown in a table. Figure 5 The categories shown are used as trigger types (for example, refer to non-patent document 4). Figure 2 The TriggerDependent Common Info subfield shown contains common information that depends on the trigger type.

[0058] In the control of the trigger frame, for example, Figure 6 As shown in FIG. 1 , during the period when a certain terminal (e.g., STA 1) is sending an uplink signal (PPDU 1), other terminals (e.g., STA 2) cannot interrupt to send an uplink signal. In this case, for example, when a more urgent transmission data occurs, the other terminals will wait to send until the next transmission opportunity (e.g., during the next transmission opportunity (TXOP)), so the delay will increase. Therefore, for example, the following method is studied. Figure 7 As shown, the transmission of high-priority data (e.g., emergency data, e.g., PPDU 2) is made to overlap (e.g., transmit data (e.g., PPDU 2) in a frequency band that partially or completely overlaps with the uplink signal (PPDU 1)) the transmission of data (e.g., PPDU 1) to other terminals (e.g., refer to non-patent document 5).

[0059] There has not been sufficient research on a control method and a trigger frame format for transmitting data (eg, emergency data) in a blanket manner during a period when other terminals are transmitting signals.

[0060] In the non-limiting embodiment of the present disclosure, an example of a control method and a trigger frame format for overlaying data transmission during a period when other terminals are transmitting signals is described.

[0061] (Implementation Method 1)

[0062] In this embodiment, a structure of control information (for example, a trigger frame) for a certain terminal to transmit data (for example, emergency data) in a covering manner during a period in which another terminal is transmitting an uplink signal will be described.

[0063] Hereinafter, the action of a terminal transmitting data (for example, emergency data) while another terminal is transmitting a signal is referred to as "preemption".

[0064] For example, Figure 8 is a diagram showing an example of preemptive transmission. Figure 8 In the example shown, STA 1 is instructed by the trigger frame to send an uplink OFDM signal (TB PPDU). Figure 8 As shown, STA 1 transmits the uplink OFDM signal at a timing corresponding to the duration (e.g., UL length) of the uplink OFDM signal indicated by the trigger frame after the short interframe space (SIFS) after receiving the trigger frame. Figure 8 For example, STA 2 generates urgent data within the UL length interval. Figure 8 As shown, STA 2 sends a signal to the same AP as the AP that is the sending destination of STA 1, within a specific time (e.g., an interval of UL length) in the entire frequency band or a part of the frequency band of the TB PPDU sent by STA 1, in such a way that the transmitted signal (e.g., TB PPDU) covers the TB PPDU of STA 1.

[0065] Will Figure 8 The sending action of STA 2 in is called "preemption (or, preemptive sending)".

[0066] The data controlled in the preemption (for example, urgent data) may be, for example, data whose time until being discarded is below a threshold, data whose allowed delay is below a threshold, or data that occurs only within an interval corresponding to the length indicated by the trigger frame.

[0067] In addition, for example, the following action can also be regarded as preemptive transmission, that is, after receiving the trigger frame, the terminal sends the urgent data occurring within the length indicated by the trigger frame.

[0068] In addition, although Figure 8 The example cites the transmission of the uplink, but the action of the AP sending data (for example, urgent downlink signal data) sent to other terminals during the period of sending the downlink signal within the length of the downlink signal can also be regarded as preemption.

[0069] [Structure of wireless communication system]

[0070] The wireless communication system of this embodiment may include, for example, Fig. 9 The AP100 and Fig.10The terminal (STA) 200 shown in the figure. In the wireless communication system, at least one of the AP 100 and the terminal 200 may also exist in two or more. The AP 100 may, for example, send control information (for example, a trigger frame) indicating preemption control to the terminal 200. The terminal 200 may, for example, receive the trigger frame and send preemption data (for example, emergency data) to the AP 100 based on the information indicated by the received trigger frame.

[0071] It should be noted that the terminal 200 may be, for example, an EHT terminal or an EHT enhanced terminal.

[0072] In addition, the AP 100 receives, for example, preemption data from each terminal 200. Next, the AP 100 separates, for example, a signal of a resource allocated to each terminal 200 from the received signal, and performs reception processing.

[0073] In addition, the AP 100 may be, for example, an AP that supports EHT or EHT enhancement. For example, in the case of communicating with an EHT enhanced terminal, the AP 100 as the communication object may support EHT enhancement. In addition, the AP 100 may have backward compatibility. For example, in addition to being able to communicate with an EHT enhanced terminal, an AP 100 that supports EHT enhancement may also communicate with a HE terminal and an EHT terminal using a trigger frame.

[0074] Fig. 9 FIG. 1 is a block diagram showing a configuration example of a portion of the AP 100 according to an embodiment of the present disclosure. Fig. 9 In the AP 100 shown, a control unit (e.g., corresponding to a control circuit) generates control information related to resources used for transmission of a second signal (e.g., preemptive transmission) during transmission of a first signal (e.g., non-preemptive transmission). A transmission unit (e.g., corresponding to a transmission circuit) transmits the control information.

[0075] Fig.10 2 is a block diagram showing a configuration example of a portion of a terminal 200 according to an embodiment of the present disclosure. Fig.10 In the terminal 200 shown, the receiving unit (e.g., corresponding to the receiving circuit) receives control information, which is control information related to resources used for transmission (preemptive transmission) of the second signal occurring during the transmission (e.g., non-preemptive transmission) of the first signal. The control unit (e.g., corresponding to the control circuit) controls the transmission (e.g., UL transmission) or reception (e.g., DL reception) of the second signal based on the control information.

[0076] [Structural example of AP100]

[0077] Fig.11It is a block diagram showing a configuration example of AP100. Fig.11 The AP 100 shown may include, for example, a scheduling unit 101 , a trigger frame generating unit 102 , a transmission signal generating unit 103 , a wireless transceiver unit 104 , and a reception signal demodulation / decoding unit 105 .

[0078] For example, the scheduling unit 101 and the trigger frame generation unit 102 may be included in an access control unit (eg, a MAC processing unit).

[0079] in addition, Fig.11 At least one of the scheduling unit 101, the trigger frame generating unit 102, the transmission signal generating unit 103 and the reception signal demodulation / decoding unit 105 shown in the figure may be included in Fig. 9 In addition, Fig.11 The wireless transceiver unit 104 shown may be included in Fig. 9 The sending part is shown.

[0080] The scheduling unit 101 can, for example, schedule the terminal 200. For example, the scheduling unit 101 allocates uplink resources to the terminal 200 that does not perform preemptive transmission but performs existing (or, usual) TB-PPDU transmission (for example, non-preemptive transmission), determines information for identifying the terminal 200 (for example, terminal ID), wireless resource information of each terminal 200 (allocated frequency band, modulation and coding scheme (MCS: Modulation and Coding Scheme), transmission power, etc.), and outputs the determined information to the trigger frame generation unit 102.

[0081] In addition, the scheduling unit 101 allocates preemptive uplink resources in at least a part of the resources allocated to the terminal 200 performing non-preemptive transmission, for example, and outputs wireless resource information (allocated frequency band, etc.) for preemptive control to the trigger frame generation unit 102 .

[0082] It should be noted that resources different from the allocated resources of the terminal 200 performing non-preemptive transmission (e.g., resources dedicated to preemption) may also be used as allocated resources for preemption. By using resources dedicated to preemption, interference between the terminal 200 performing non-preemptive transmission and the terminal 200 performing preemptive transmission can be reduced.

[0083] The trigger frame generation unit 102 generates a trigger frame including a general information field, a user information field, and a special user information field based on, for example, the terminal ID, the wireless resource information of each terminal 200, and the control information related to preemption input from the scheduling unit 101. The trigger frame generation unit 102 outputs the generated trigger frame to the transmission signal generation unit 103.

[0084] It should be noted that the trigger frame including the control information related to the preemption may also include the preemption transmission condition described later. The format of the trigger frame including the control information related to the preemption and an example of the transmission condition will be described later.

[0085] The transmission signal generation unit 103 performs error correction coding and modulation processing on the transmission data signal including the trigger frame input from the trigger frame generation unit 102 , for example, and outputs the modulated data signal to the wireless transmission / reception unit 104 .

[0086] It should be noted that when the modulated data signal is an orthogonal frequency division multiplexing (OFDM) signal, AP100 (for example, the transmitting signal generating unit 103) can map the modulated signal to a specified frequency resource, perform inverse fast Fourier transform (IFFT: Inverse Fast Fourier Transform) or inverse Fourier transform (IDFT: Inverse Discrete Fourier Transform) (hereinafter referred to as "IFFT / IDFT") processing to convert it into a time waveform, and add a cyclic prefix (CP: Cyclic Prefix) to form an OFDM signal.

[0087] The wireless transceiver 104 performs wireless transmission processing such as D / A (Digital / Analog) conversion and up-conversion to a carrier frequency on the modulated signal input from the transmission signal generator 103, and transmits the signal after the wireless transmission processing to the terminal 200 via the antenna. In addition, the wireless transceiver 104 receives a signal transmitted from the terminal 200 via the antenna, performs wireless reception processing such as down-conversion to a baseband frequency and A / D (Analog / Digital) conversion on the received signal, and outputs the signal after the wireless reception processing to the reception signal demodulation / decoding unit 105.

[0088] The received signal demodulation / decoding unit 105 performs demodulation and decoding processing on the signal input from the wireless transceiver unit 104, and obtains the data sent from the terminal 200. For example, the received signal demodulation / decoding unit 105 can output information (for example, ACK) indicating whether the obtained data has been correctly decoded to the scheduling unit 101. It should be noted that when the signal input to the received signal demodulation / decoding unit 105 is an OFDM signal, the AP 100 (for example, the received signal demodulation / decoding unit 105) can perform CP removal processing and FFT / DFT processing.

[0089] [Configuration Example of Terminal 200]

[0090] Fig.12 It is a block diagram showing a configuration example of the terminal 200. Fig.12 The terminal 200 shown may include, for example, a wireless transceiver unit 201 , a received signal demodulation / decoding unit 202 , a trigger frame determination unit 203 , a preemptive transmission control unit 204 , and a transmission signal generation unit 205 .

[0091] For example, at least one of the trigger frame determination unit 203 and the preemptive transmission control unit 204 may be included in an access control unit (eg, a MAC processing unit).

[0092] in addition, Fig.12 At least one of the received signal demodulation / decoding unit 202, the trigger frame determination unit 203, the preemptive transmission control unit 204, and the transmission signal generation unit 205 shown in the figure may be included in, for example, Fig.10 In addition, Fig.12 The wireless transceiver unit 201 shown may be included in Fig.10 The receiving portion shown.

[0093] The wireless transceiver 201 receives a received signal using, for example, an antenna, performs wireless reception processing such as down-conversion and A / D conversion on the received signal, and outputs the signal after the wireless reception processing to the received signal demodulation / decoding unit 202. In addition, the wireless transceiver 201 performs wireless transmission processing such as up-conversion and D / A conversion on the signal input from the transmission signal generation unit 205, and transmits the signal after the wireless transmission processing from the antenna.

[0094] The received signal demodulation / decoding unit 202 performs demodulation processing and decoding processing on the received data input from the wireless transceiver unit 201, and outputs the decoded signal as a received data signal. In addition, the received signal demodulation / decoding unit 202 outputs control information related to the trigger frame in the received data signal to the trigger frame determination unit 203, for example. It should be noted that when the signal input to the received signal demodulation / decoding unit 202 is an OFDM signal, the terminal 200 (for example, the received signal demodulation / decoding unit 202) can perform CP removal processing and FFT / DFT processing, for example.

[0095] The trigger frame determination unit 203 extracts information from the general information field, the user information field, and the special user information field contained in the trigger frame, decodes the terminal-specific information including the wireless resource information (for example, including the allocated frequency band, MCS, transmission power, etc.), and outputs it to the transmission signal generation unit 205. In addition, the trigger frame determination unit 203 decodes the control information related to the preemption in the information contained in the trigger frame, and outputs it to the preemption transmission control unit 204.

[0096] The preemption transmission control unit 204 controls the preemption transmission, for example, based on the preemption-related control information input from the trigger frame determination unit 203. For example, the preemption transmission control unit 204 can control the transmission of data (for example, urgent data) within the duration (for example, length) notified by the trigger frame based on the preemption resource information in the preemption-related control information.

[0097] In addition, for example, when the trigger frame includes a preemptive transmission condition (for example, information related to the transmission condition such as a transmittable traffic identifier (TID), length, and transmission timing), the preemptive transmission control unit 204 can control the preemptive transmission according to the transmission condition. It should be noted that an example of the preemptive transmission condition will be described later.

[0098] The preemptive transmission control unit 204 outputs information for preempting data transmission to the transmission signal generation unit 205, for example.

[0099] The transmission signal generating unit 205 generates a signal for uplink transmission (e.g., TB PPDU) based on the control information (e.g., length, MCS, etc.) input from the trigger frame determination unit 203. In addition, the transmission signal generating unit 205 generates a signal for preemptive transmission (e.g., TB PPDU or multi-user (MU: Multi-user) PPDU) based on the information input from the preemptive transmission control unit 204. The transmission signal generating unit 205 performs error correction coding and modulation processing on the generated transmission signal, and outputs the modulated data signal to the wireless transceiver unit 201. It should be noted that when the modulated signal is an OFDM signal, the terminal 200 (e.g., the transmission signal generating unit 205) can perform IFFT / IDFT processing after mapping the modulated signal to the frequency resources, and add a CP, thereby forming an OFDM signal.

[0100] [Operation Example of AP 100 and Terminal 200]

[0101] Next, an operation example of the AP 100 and the terminal 200 according to the present embodiment will be described.

[0102] AP 100 generates control information related to resources used for preemption transmission (e.g., resource units (RU)) and transmits it to terminal 200. Terminal 200 receives control information related to resources used for preemption transmission and controls transmission of preemption signals (e.g., emergency data).

[0103] For example, the AP 100 uses a trigger frame to instruct the multiple terminals 200 to provide control information related to preemption.

[0104] The following describes methods of instructing preemptive transmission (transmission instruction method 1 and transmission instruction method 2).

[0105] [Send instruction method 1]

[0106] In the transmission indication method 1, the control information related to the resources used for preempting the transmission may be included in the user information field of the trigger frame.

[0107] For example, the AP 100 may use the user information field of the trigger frame to notify the terminal 200 of the resources used for preemptive transmission (or whether the preemptive transmission can be performed). The terminal 200 may perform preemptive transmission in the preempted resources notified by the user information field of the trigger frame. For example, it may be assumed that the terminal 200 may send preemptive data (e.g., urgent data) at any timing within a period corresponding to the duration (e.g., length) indicated by the trigger frame.

[0108] In this way, by using the user information field of the trigger frame to notify the resources used for preemptive transmission (or whether preemptive transmission is possible), the terminal 200 can perform preemptive transmission, for example, reducing the transmission delay of urgent data.

[0109] The following example is described, that is, using Figure 3 The user information field (eg, AID12 subfield) of the trigger frame shown notifies information related to whether preemptive transmission is possible, such as notifying information related to resources that can be used for preemptive transmission.

[0110] <Resource Notification Example 1>

[0111] In resource notification example 1, the resources notified by the following user information field are set as resources that can be used for preemptive transmission, and the user information field is a user information field in which the AID12 subfield in the trigger frame is set to a value specified for preemption. For example, the AID of the user information field containing control information related to the resources used for preemptive transmission can be a value associated with preemptive transmission.

[0112] As an example, the value of the AID12 subfield specified for preemption may be set to a value not used in the existing standard (e.g., 2008). In this case, the terminal 200 may set the resources notified by the user information field in which the AID12 subfield is set to 2008 as resources that can be used for preemptive transmission.

[0113] For example, all terminals 200 may be allowed to preemptively transmit in the resources (RU) notified by the RU allocation subfield (Allocation subfield) of the user information field in which the AID12 subfield is set to 2008.

[0114] In addition, for example, when the user information field in which the AID12 subfield is set to 2008 does not exist in the trigger frame received by the terminal 200, the terminal 200 can determine that the preemptive transmission is not possible (the preemptive transmission is not allowed).

[0115] It should be noted that the notification method that can be used to preempt the transmission resources is not limited to the method using the RU allocation subfield. For example, it can also be a method of notifying multiple RUs using the RU allocation and RA-RU information subfields in the same way as the existing random access (UL OFDMA-based random access (UORA)) control.

[0116] In addition, for example, the following structure may be adopted, that is, based on the control of the OFDMA contention window (OCW) similarly to random access, a terminal 200 whose OBO (OFDM random access backoff) counter is 0 may perform preemptive transmission (or allow transmission), and a terminal 200 whose OBO counter is a value different from 0 may not perform preemptive transmission (or not allow transmission). When OCW is applied, a value for preemptive transmission (for example, a value dedicated to preemption) may be set as the value of OCWmin and OCWmax.

[0117] For example, by setting the OCWmax value for preemption transmission to be smaller than that for other transmissions, the OBO counter is more likely to become 0, thereby increasing the chance of terminal 200 sending preemption data, thereby allowing the preemption signal to be sent with a lower delay.

[0118] In addition, for example, by setting the OCWmax value for preemption transmission to be larger than that for other transmissions, the OBO counter is less likely to become 0, thereby suppressing the opportunity for terminal 200 to transmit preemption data, thereby reducing interference with other terminals.

[0119] It should be noted that the setting value of the AID12 subfield for indicating preemptive transmission is not limited to 2008, and may be other unused AIDs (for example, 2009).

[0120] Alternatively, the setting value of the AID12 subfield for indicating preemptive transmission is not limited to unused AIDs such as 2008, and a value (e.g., 2006) from 1 to 2007 used in the existing standard may be set (or selected). In this case, the AP 100 may not use the value for indicating preemptive transmission as the AID of other terminals, for example. That is, the AP 100 may not use the value for indicating preemptive transmission to indicate non-preemptive transmission.

[0121] In addition, the resource to be seized is not limited to one, and multiple resources to be seized may be notified. In the case of notifying multiple resources to be seized, for example, the setting value of the AID12 subfield for indicating the preemption transmission may be set for each of the multiple resources to be seized. For example, multiple AIDs (for example, 2008 and 2009) may be set for each of the multiple resources to be seized. The AID corresponding to the resource to be seized may be an unused value in the existing standard or a used value.

[0122] <Resource Notification Example 2>

[0123] In resource notification example 2, for example, a plurality of user information fields in a trigger frame may include information indicating whether the user information field is related to preemptive transmission.

[0124] As an example, the reserved subfield of the user information field of the trigger frame may be used to notify the terminal 200 whether the resource notified by the user information field is a preempted resource. For example, when the value of the reserved subfield is 0, the corresponding user information field may include information related to non-preempted resources, and when the value of the reserved subfield is 1, the corresponding user information field may include information related to preempted resources.

[0125] In addition, in resource notification example 2, for example, the AID of the user information field related to preemptive transmission may also be the value of the AID of one of the multiple terminals 200 that can perform preemptive transmission. For example, in the user information field, the AID12 subfield may be replaced with the "Starting AID subfield", which contains the front AID (starting AID) of the AIDs of the multiple terminals 200 that can perform preemptive transmission. For example, terminals 200 having AIDs in the range of starting AID to starting AID+X may be allowed to perform preemptive transmission in the RU notified by the RU allocation subfield of the user information field. For example, when the value of the reserved subfield of the user information field is 1, the AID notified by the AID12 subfield is 10, and X=5, terminals 200 in the range of AID=10 to 15 may perform preemptive transmission.

[0126] It should be noted that X may be a value specified in the specification, or may be notified to the terminal 200 by a control signal such as a trigger frame or a beacon. For example, the AP 100 may include the number of STAs that can perform preemptive transmission (equivalent to the value of X+1) in a control signal such as a trigger frame or a beacon and notify the terminal 200. In addition, the AP 100 may, for example, set X=2. Y -1, determines the STA number exponential value (for example, Y), includes it in the control signal and notifies the terminal 200. In addition, the AID12 subfield is not limited to including the starting AID, and may also include the AID of at least one terminal 200 among the multiple terminals 200 that are allowed to preempt the transmission (for example, the last AID, etc.), as long as it is a method that can determine the multiple terminals 200 that are allowed to preempt the transmission based on the value of the AID12 subfield.

[0127] Thus, in resource notification example 2, the reserved subfield and AID12 subfield of the user information field are used to notify multiple terminals 200 that are allowed to preempt transmission. In resource notification example 2, by notifying a specific terminal 200 of the preempted resources, resource conflicts between terminals 200 can be reduced compared to resource notification example 1 (for example, notifying all terminals 200).

[0128] In addition, in the resource notification example 2, similarly to the resource notification example 1, the same resource allocation or OCW as the random access can also be applied.

[0129] In addition, the subfield for notifying whether the resource is preempted (the subfield for notifying whether the resource is preempted) is not limited to the reserved subfield of the user information field, and may be other fields in the user information field.

[0130] <Resource Notification Example 3>

[0131] In resource notification example 3, similar to resource notification example 2, the multiple user information fields in the trigger frame may include information indicating whether the user information field is related to preempted transmission. For example, the reserved subfield of the user information field of the trigger frame may be used to notify the terminal 200 whether the resource notified by the user information field is a preempted resource. For example, when the value of the reserved subfield is 0, the corresponding user information field may include information related to non-preempted resources, and when the value of the reserved subfield is 1, the corresponding user information field may include information related to preempted resources.

[0132] In addition, in resource notification example 3, for example, the AID in the user information field related to preemptive transmission may also be the value of the AID of a terminal 200 that can perform preemptive transmission. For example, preemptive transmission may be permitted for a terminal 200 notified by the AID12 subfield of the user information field, and preemptive transmission may not be permitted for a terminal 200 notified by the AID12 subfield of the user information field.

[0133] It should be noted that the subfield for notifying whether the resource is preempted (the subfield for notifying whether the resource is preempted) is not limited to the reserved subfield of the user information field, but may be other fields in the user information field.

[0134] By setting (for example, limiting) the terminal 200 that is allowed to preemptively transmit to one terminal as in the resource notification example 3, resource conflicts among the terminals 200 can be reduced, for example, compared to the resource notification example 2 (or the resource notification example 1).

[0135] In addition, the following structure may be adopted, that is, the terminal 200 sends information related to whether it is possible to send data by preemption, such as information related to whether urgent data may occur in the near future, to the AP 100 in advance. The terminal 200 may also include the information related to whether it is possible to send data by preemption in, for example, a buffer status report (BSR) or a null data packet (NDP) Feedback Report Poll (NFRP) and send it. For example, the AP 100 may determine the terminal 200 that is allowed to preempt the transmission based on the information from the terminal 200. For example, the AP 100 can determine whether urgent data may occur on the terminal 200 side in the future, and therefore can efficiently allocate the AID to be preempted, thereby improving the efficiency of resource utilization.

[0136] The above describes an example of notification that can be used to preempt transmission resources.

[0137] As described above, in the preemptive transmission indication method 1, the AID12 subfield of the user information field is used to set (for example, limit) the terminal 200 that can perform preemptive transmission. Here, in the resource notification example 1 or the resource notification example 2, when there are multiple terminals 200 that perform preemptive transmission, the signals between the terminals may conflict. In addition, if a terminal 200 performs preemptive transmission, it is possible to interfere with the signal of the (non-preemptive) terminal that does not perform preemptive transmission.

[0138] Therefore, for example, the following method is described, which uses a trigger frame to notify terminal 200 of conditions (transmission conditions) related to whether terminal 200 is allowed to preempt transmission, thereby reducing the probability of signal conflicts between terminals 200 performing preemptive transmission, and also reducing interference to other terminals.

[0139] The following describes the preemptive transmission conditions 1 to 3.

[0140] It should be noted that at least part of the transmission conditions described below may not be notified to the terminal 200 by a trigger frame but may be specified in the specification, or may be notified to the terminal 200 by other control signals such as beacons. In addition, at least two of the transmission conditions 1 to 3 may be applied in combination.

[0141] <Delivery Condition 1>

[0142] In the transmission condition 1, whether the terminal 200 can perform preemptive transmission (or whether the preemptive transmission is restricted) is set by a traffic identifier (TID) indicating the traffic type.

[0143] For example, AP 100 may use a trigger frame to notify terminal 200 of TIDs (eg, TID thresholds) for which preemptive transmission is permitted. For example, preemptive transmission of data of TIDs greater than or equal to the TID specified by the trigger frame (eg, any one of 0 to 7) may be permitted.

[0144] Here, for example, the TID is related to the allowed delay amount, and it can be that the larger the value of the TID, the smaller the allowed delay amount (for example, a low delay can be required). Therefore, by specifying the TID by the trigger frame, the terminal 200 can preempt the data with high transmission delay requirements. According to the transmission condition based on the TID, it is not easy to preempt the data with low transmission delay requirements, which can reduce the conflict and interference of signals between the terminals 200, and efficiently send urgent data.

[0145] For example, when the trigger frame notifies TID=4 (threshold), terminal 200 can preemptively send data with TID=4 or above (e.g., TID=4, 5, 6, 7), but cannot preemptively send data with less than TID=4 (e.g., TID=0, 1, 2, 3).

[0146] It should be noted that whether or not to preempt transmission is not limited to the case where it is indicated based on the threshold value of TID, and for example, the value of TID may be indicated separately in the form of a bitmap. For example, in the case of a bitmap TIDbitmap={0, 0, 0, 0, 1, 1, 1, 1} corresponding to each value of TID (e.g., 8 values ​​of TID=0 to 7), the terminal 200 can preempt the transmission of data of TID=4, 5, 6, 7, but cannot preempt the transmission of data of TID=0, 1, 2, 3.

[0147] In addition, when indicating whether to send in the form of a bitmap, it is not limited to the structure of indicating the value of all TIDs, for example, it can also be a structure of indicating the value of a part of TIDs. For example, it can also be a structure as follows, that is, the TIDbitmap is set to 4 bits instead of 8 bits, indicating whether the data of TID=4, 5, 6, 7 can be preempted and sent. In this way, the number of bits of control information can be reduced.

[0148] In addition, the value indicating whether or not the transmission can be preempted is not limited to the TID, and may be other values. For example, information related to the allowed delay amount (e.g., access category (AC) or control information that adds an ID to each allowed delay amount) similar to the TID may be used to indicate (or notify) whether or not the transmission can be preempted.

[0149] In addition, the value (threshold) of TID that allows preemptive transmission is not limited to TID=4, but may be other values. In addition, the size of the bitmap TIDbitmap is not limited to 4 bits or 8 bits, but may be other values.

[0150] <Delivery Condition 2>

[0151] In sending condition 2, whether terminal 200 can perform preemptive sending (or, restrict preemptive sending) is set according to the duration of the signal sent in the preemption (or, signal length), that is, according to the duration of the preamble code (Preamble) and data (for example, the length of PPDU).

[0152] Fig.13 An example of notifying the length of the PPDU that can be preempted. For example, the AP 100 can set a field (preemption length field) in the trigger frame to notify the value related to the length of the signal that allows preemption. Fig.13 In the trigger frame, "length_TF (LENGTH_TF)" is equivalent to the UL length notified in the general information field of the trigger frame.

[0153] exist Fig.13 In the example shown, the duration of the PPDU that can be preempted is set (or limited) to 1 / 2, 1 / 4, 1 / 8, or 1 / 16 of the UL length. For example, the terminal 200 may send preempted data of a duration less than the duration corresponding to the value (one of 0 to 3) notified in the preemption length field, but may not send preempted data of a duration longer than the duration corresponding to the value notified in the preemption length field.

[0154] In this way, according to the transmission condition based on the duration of the preemption signal, an upper limit of the duration allowed for preemption transmission is set (for example, restricted), thereby reducing interference caused by the preemption transmission of terminal 200 to other terminals.

[0155] It should be noted that the preemption length of the notification is not limited to the Fig.13 The method of notifying the UL length (length_TF) in the general information field of the trigger frame shown may be a method based on a value indicating the transmission time in the same manner as the UL length.

[0156] Alternatively, the number of bits used to indicate the preemption length may be reduced by reducing the time range (or candidate) that can indicate the preemption length. Fig.13 Some (eg, two) of the four candidates for the preemption length shown can reduce the number of bits used for notification to 1. It should be noted that the notified duration may be a shorter duration, a longer duration, or any duration.

[0157] In addition, the value of the UL length notified by the common information field is not limited to the case where the length field of the L-SIG included in the preamble of the TB PPDU is set, and the value of the length indicated by the transmission condition 2 may be set.

[0158] In addition, the transmission condition 2 may be a structure that allows preemptive transmission within a time period that is within the notified preemption length.

[0159] <Delivery Condition 3>

[0160] In the transmission condition 3, whether or not the terminal 200 can perform preemptive transmission (or restricting preemptive transmission) is set according to the timing of transmitting a signal in preemption.

[0161] Fig.14 This is an example of notifying the timing of preemptive transmission. For example, the AP 100 may set a field (a Start transmission timing field) in the trigger frame to notify a value related to the timing at which preemptive transmission can be performed. Fig.14 In the trigger frame, "length_TF" is equivalent to the UL length notified in the general information field of the trigger frame. AP100 can also indicate the UL response signal to the trigger frame (for example, Figure 8 For example, AP100 may indicate a time domain A-PPDU (aggregated PPDU) as a TB PPDU, and set the preamble timing of each PPDU constituting the A-PPDU to a timing at which preemptive transmission can be performed.

[0162] exist Fig.14 In the example shown, the timing at which preemptive transmission can be performed is set (or limited) to segments of 1 / 2, 1 / 4, 1 / 8, and 1 / 16 of the UL length. For example, the terminal 200 can perform preemptive transmission at the transmission timing corresponding to the value (one of 0 to 3) notified in the start transmission timing field, and not send preemptive data at a timing different from the transmission timing corresponding to the value notified in the start transmission timing field.

[0163] Fig.15 FIG. 1 is a diagram showing an example of the timing at which preemptive transmission can be performed. Fig.15 As an example, the timing of a 1 / 2 segment of the UL length and the timing of a 1 / 4 segment of the UL length are shown. Fig.15 As shown, when the terminal 200 is notified of the timing of the 1 / 2 segment of the UL length, it can start preemptive transmission at the timing (one timing) in the middle of the UL length. Fig.15 As shown, when the terminal 200 is notified of the timing of the 1 / 4 segment of the UL length, it can start preemptive transmission at any one of the three timings within the time corresponding to the UL length.

[0164] In this way, in transmission condition 3, according to the transmission condition based on the transmission timing of preemption transmission, the length of the preemption signal in the UL length interval is limited in the same manner as in transmission condition 2, thereby reducing interference with other terminals.

[0165] In transmission condition 3, AP100 only needs to perform preemptive reception processing (preamble detection processing) at the start timing of preemptive transmission. That is, AP100 does not need to perform preemptive reception processing at a timing different from the start timing of preemptive transmission. This can reduce the processing amount of AP100.

[0166] In addition, when multiple AIDs (eg, multiple user information fields) are used to notify the preempted resources, AID-specific transmission timings may be set. Thus, for example, by staggering the transmission timings by AID, conflicts in preempted transmissions can be reduced.

[0167] The above describes the preemptive transmission conditions 1 to 3.

[0168] Next, Figure 3 The user information field of the trigger frame shown or Figure 4 An example of a format in which information related to the above-mentioned preemptive transmission condition is notified in the special user information field shown in FIG.

[0169] For example, the fields described later in the user information field may not necessarily be used for preemptive transmission. Thus, by replacing all or part of the following fields with fields indicating information related to transmission conditions (e.g., a TID threshold, a preemption length, or a field for starting transmission timing), it is possible to suppress an increase in control information overhead and notify transmission conditions.

[0170] <Field Example 1>

[0171] The transmission condition may be notified in the field of the user information field indicating the MCS of the data to be transmitted uplink. Figure 3 The transmission condition is notified in the "UL EHT-MCS subfield" of the user information field shown.

[0172] For example, it is assumed that the urgency of preemptive transmission is high, and therefore, it is assumed that transmission using a low MCS is performed in order to perform transmission without error. Thus, for example, by fixedly setting the MCS in preemptive transmission (for example, setting it to the lowest MCS), the MCS may not be notified in the UL EHT-MCS subfield (for example, there is no need to notify the MCS). Thus, by replacing the UL EHT-MCS subfield with a field indicating information related to the transmission condition, it is possible to suppress an increase in the overhead of the control information and to notify the transmission condition.

[0173] It should be noted that the MCS value (fixed value) of the preemptive transmission may be specified in the specification, or may be notified to the terminal 200 by other control information such as a beacon. In addition, the MCS value is not limited to the lowest MCS, and may be other values.

[0174] In addition, it is not limited to the case where all UL EHT-MCS subfields (for example, 4 bits) are replaced with fields for notifying transmission conditions. All UL EHT-MCS subfields may be used as fields where a portion of the bits of the field (for example, 2 bits (for example, MCS = one of 0, 1, 2, and 3)) are used to notify MCS, and the remaining bits (for example, 2 bits) notify the transmission conditions. It should be noted that the number of bits of a portion is not limited to 2 bits, and may be another number of bits.

[0175] It should be noted that the field name "UL EHT-MCS subfield" is an example and may be different. For example, in EHT enhancement, the UL EHT-MCS subfield may be changed to the name "UL EHT enhancement-MCS", so as long as it is a field for notifying MCS, the field name is not limited to this.

[0176] <Field Example 2>

[0177] The transmission condition can be notified in the field indicating the spatial stream (SS: Spatial stream) in the user information field. Figure 3 The transmission condition is notified in the "SS allocation / RA-RU information subfield" of the user information field shown.

[0178] For example, it is assumed that the urgency of preemptive transmission is high, and therefore, it is assumed that a single stream will be transmitted in order to transmit without error. Thus, for example, by fixedly setting the transmission stream in preemptive transmission (for example, setting it to 1), the number of streams may not be notified in the SS allocation subfield (for example, there is no need to notify the stream). Thus, by replacing the SS allocation subfield with a field indicating information related to the transmission condition, it is possible to suppress an increase in the overhead of the control information and to notify the transmission condition.

[0179] It should be noted that in the above-mentioned resource notification example 1 and resource notification example 2, when the RA-RU information subfield is used to notify the resource, since this field is used, the transmission condition may be notified using a field different from this field.

[0180] <Field Example 3>

[0181] The transmission condition may be notified in a field of the user information field indicating a value related to the transmission power of the uplink (or the reception power of the signal in the AP 100 (for example, an expected value or a target value)). Figure 3 The transmission condition is notified in the "UL target received power subfield" of the user information field shown.

[0182] For example, it is assumed that the urgency of preemptive transmission is high, and therefore, it is assumed that the transmission power is set to a high value (e.g., maximum power) in order to transmit without error. Thus, for example, by setting the applicable maximum power by the terminal 200 in preemptive transmission, the transmission power may not be notified in the UL target received power subfield (e.g., there is no need to notify the transmission power). Thus, by replacing the UL target received power subfield with a field indicating information related to the transmission condition, it is possible to suppress an increase in the overhead of the control information and notify the transmission condition.

[0183] It should be noted that the transmission power set in preemptive transmission is not limited to the maximum power.

[0184] <Field Example 4>

[0185] Can be Figure 4The transmission condition is notified in the "reserved subfield" of the special user information field shown. The reserved subfield is not used in the existing standard, and therefore, can also be used for other purposes (for example, for notifying the transmission condition).

[0186] <Field Example 5>

[0187] For example, when the trigger frame type is "basic", you can Fig.16 The trigger shown depends on the notification sending conditions in the user information field.

[0188] For example, the data size of the preempted transmission data (e.g., urgent data) is likely to be small, and therefore, the Aggregate MAC protocol data unit (A-MPDU) is likely not to be applied. Therefore, when the trigger frame type is "basic", the MPDU MU Spacing Factor subfield is not used, and therefore, it can also be replaced by a field indicating information related to the transmission condition.

[0189] In addition, for example, the possibility that the preempted transmission data is data of a single TID is high, so the possibility that the TID aggregation limit subfield is not applied is high. Therefore, when the trigger frame type is "basic", the TID aggregation limit subfield can also be replaced with a field indicating information related to the transmission condition.

[0190] In addition, for example, when notifying a transmittable TID as a transmission condition (eg, transmission condition 1), the preferred AC subfield may not be used. Therefore, in this case, the preferred AC subfield may be replaced with a field indicating information related to the transmission condition.

[0191] In addition, you can Fig.16 The trigger-dependent user information field indicates the sending condition in the "reserved subfield". The reserved subfield is not used in the existing standard, and therefore, can also be used for other purposes (for example, can be used to indicate the sending condition).

[0192] For example, you can use Fig.16 The trigger shown notifies the transmission condition using all or part of the above subfields of the user information field.

[0193] The above describes an example of a field indicating information related to the preemptive sending condition. It should be noted that the field indicating information related to the preemptive sending condition is not limited to the above example, and may also be other fields. For example, the field indicating information related to the preemptive sending condition may also be other fields that are not used in whole or in part in the preemptive sending.

[0194] Next, an example of a format in which all or part of the transmission conditions are transmitted using the above-mentioned fields will be described.

[0195] <Format Example 1>

[0196] exist Fig.17 In the format example shown, in the "UL EHT-MCS subfield" and "SS allocation / RA-RU information subfield" within the user information field of the trigger frame, sending condition 1 (for example, preemption TID), sending condition 2 (for example, preemption length) and sending condition 3 (preemption timing) are notified.

[0197] <Format Example 2>

[0198] exist Fig.18 In the format example shown, in the "UL EHT-MCS subfield" and "UL target receive power subfield" within the user information field of the trigger frame, sending condition 1 (e.g., preemption TID), sending condition 2 (e.g., preemption length) and sending condition 3 (e.g., preemption timing) are notified.

[0199] <Format Example 3>

[0200] exist Fig.19 In the format example shown, the transmission condition 1 (for example, preempting TID) is notified in the "UL EHT-MCS subfield" in the user information field of the trigger frame.

[0201] It should be explained that Fig.17 , Fig.18 and Fig.19 The format shown is an example, and at least one of the field for notifying the transmission condition, the correspondence between the transmission conditions 1 to 3 and the field, and the number of bits for notifying the transmission condition may also be different from the Fig.17 , Fig.18 and Fig.19 Different. In addition, at least one of the transmission conditions 1 to 3 may be applied, or multiple transmission conditions may be applied. In addition, a portion of the transmission conditions among the multiple transmission conditions may be notified to the terminal 200 by a trigger frame, and the remaining transmission conditions may be specified in the specification, or may be notified to the terminal 200 by other control information.

[0202] The above describes the preemptive transmission instruction method 1.

[0203] [Send instruction method 2]

[0204] In the transmission indication method 2, control information related to the resources used for preemptive transmission (for example, whether preemptive transmission is possible) may be included in the general information field of the trigger frame.

[0205] For example, the AP 100 may use the general information field of the trigger frame to notify the terminal 200 whether the preemptive transmission is possible. The terminal 200 may perform the preemptive transmission according to whether the preemptive transmission is possible notified by the general information field of the trigger frame.

[0206] For example, you can Figure 2 At least a portion of the "reserved subfield" (e.g., B22, B25, B53, B63) or the "EHT reserved subfield" (e.g., B56-B62) of the general information field shown is replaced with a "Pre-emption enable subfield".

[0207] For example, when 0 is set in the Preemption Enable subfield, it can be indicated that preemption transmission cannot be performed within the frequency band in which the trigger frame is transmitted and the time (for example, UL length) notified by the trigger frame. In addition, for example, when 1 is set in the Preemption Enable subfield, it can be indicated that the frequency band in which the trigger frame is transmitted and preemption transmission can be performed within the time notified by the trigger frame.

[0208] It should be noted that the format of the PPDU used for preemptive transmission can be TB-PPDU or MU PPDU.

[0209] In addition, the resource for sending the preemption data (eg, the location of the RU) may also be, for example, any RU within the frequency band in which the trigger frame is sent.

[0210] In addition, the setting values ​​of MCS, target reception power, etc. notified in the user information field may be arbitrary values, and the terminal 200 may freely determine the MCS and transmission power. It should be noted that the setting values ​​of MCS, target reception power, etc. are not limited to arbitrary values, and may be specified in the specification as fixed values, or may be notified to the terminal 200 by other control information such as a beacon.

[0211] Thus, in the preemptive transmission indication method 2, the general information field of the trigger frame is used to notify whether preemption is possible, thereby allowing the terminal 200 to perform preemptive transmission, for example, to reduce the transmission delay of urgent data.

[0212] It should be noted that the following structure may be used, that is, the AID (for example, AID=2008) in the AID12 subfield of the user information field, which is not used in the existing standard, is used to notify the MCS or target received power and other parameters used for preemptive transmission. In addition, the transmission instruction method 2 may also be a structure in which, similar to the transmission instruction method 1, the structure of notifying the preemptive transmission conditions in the user information field.

[0213] The above describes the method of preemptively sending an indication.

[0214] Thus, in this embodiment, AP100 uses a trigger frame to send control information to terminal 200, and the control information is control information related to the resources used for preemptive transmission (or whether preemptive transmission can be performed) occurring during the transmission period of the signal indicated by the trigger frame. Terminal 200 controls the transmission of the preemptive signal based on the control information contained in the trigger frame.

[0215] Thus, for example, the terminal 200 can transmit data (e.g., urgent data) in a covering manner during the period when other terminals are transmitting signals based on the control information indicated by the trigger frame. Thus, according to this embodiment, even in the case of preemptive transmission, the time delay can be reduced, thereby improving the efficiency of signal transmission control in wireless communication.

[0216] (Implementation Method 2)

[0217] For the uplink signal (e.g., TB-PPDU) sent due to the indication of the trigger frame, for example, even if resources below the 20MHz band are allocated, L-STF / L-LTF / L-SIG / RL-SIG / U-SIG (e.g., the signal of the pre-EHT modulation field) will still be sent in the 20MHz band.

[0218] Fig. 20 is a diagram showing an example of preemption. Fig. 20 As shown in FIG. 1 , when the resource allocated to the preemption is less than 20 MHz, the EHT-STF / LTF, data, and PE (Packet Extension) field signals (e.g., EHT modulation field signals) in the preempted signal are sent in the frequency band allocated to the preemption. Fig. 20 As shown, the signal of the L-STF / L-LTF / L-SIG / RL-SIG / U-SIG field in the preempted transmitted signal (eg, the signal of the pre-EHT modulation field) is transmitted in the 20 MHz frequency band.

[0219] In this case, Fig. 20Although the preempted EHT-STF / LTF, data, and PE field signals (e.g., the EHT modulation field signals) may interfere with the STA 2 signal, they will not interfere with the STA 1 signal. On the other hand, the preempted L-STF / L-LTF / L-SIG / RL-SIG / U-SIG (e.g., the pre-EHT modulation field signals) may interfere with the signals of both STA 1 and STA 2.

[0220] In this embodiment, the following description is given: Fig. 20 The PPDU format in preemptive transmission for suppressing interference (eg, a PPDU format dedicated to preemptive transmission) is shown.

[0221] The wireless communication system according to this embodiment may include AP 100 and terminal 200 similarly to Embodiment 1.

[0222] The structure of the AP 100 in this embodiment may be the same as that in the first embodiment.

[0223] The configuration of the terminal 200 of this embodiment may be the same as that of the embodiment 1. In the terminal 200 of this embodiment, for example, the operation of the transmission signal generation unit 205 may be different from that of the embodiment 1.

[0224] The transmission signal generation unit 205 generates a transmission signal (for example, TB-PPDU) for uplink transmission based on the control information (for example, length, MCS, etc.) input from the trigger frame determination unit 203, for example.

[0225] In addition, the transmission signal generation unit 205 generates a transmission signal (e.g., TB-PPDU or MU-PPDU) for preempting transmission, for example, based on the control information input from the preemption transmission control unit 204. In the case of preemption transmission, the transmission signal generation unit 205 generates a transmission signal based on a format for preemption (e.g., preempting TB-PPDU or preempting MU PPDU). It should be noted that an example of a format for preemption (e.g., referred to as a "preemption transmission format") will be described later.

[0226] The transmission signal generating unit 205 performs error correction coding and modulation processing on the generated transmission signal, and outputs the modulated data signal to the wireless transceiver unit 201. It should be noted that when the modulated signal is an OFDM signal, the terminal 200 (for example, the transmission signal generating unit 205) can perform IFFT / IDFT processing and add CP after mapping the modulated signal to the frequency resource, thereby forming an OFDM signal.

[0227] An example of the PPDU format for preemptive transmission is described below.

[0228] The format of the PPDU used for preemptive transmission may be different from the format of the existing PPDU (e.g., TB PPDU or MU PPDU, etc.). For example, the PPDU used for preemptive transmission may be a structure in which the portion from L-STF to EHT-LTF of the existing PPDU (e.g., the portion earlier than the data) is deleted, and a new LTF (e.g., "preemptive LTF") used for packet supplementation, level control, and channel estimation is added.

[0229] In addition, for example, Fig.21 As shown, the preemption LTF (or, preamble) may be allocated to the allocated resource (eg, RU) of the preemption signal indicated by the trigger frame and transmitted.

[0230] exist Fig.21 In the example shown, if the resource allocated for preemption is less than 20 MHz, the preempted LTF and data will be sent in the frequency band allocated for preemption. Fig.21 In the process, although the preempted sent signal (preempted LTF and data) may interfere with the signal of STA 2, it will not interfere with the signal of STA 1.

[0231] In this way, by applying the PPDU format for preemptive transmission, it is possible to suppress interference caused by preemptive transmission to a terminal transmitting other TB-PPDUs, or to suppress the stopping of transmission of other terminals due to preemptive transmission.

[0232] In addition, by introducing the preemption LTF, the preamble length can be shortened in the preemption transmission, thereby reducing the interference caused to the terminal sending other TB-PPDUs.

[0233] It should be noted that the structure of the preempted LTF may be a format including EHT-LTF and EHT-STF, or a format including EHT-LTF. In addition, when EHT-LTF is used as the preempted LTF, the number of symbols may be fixed to 1 symbol. Preempted transmission may support a single stream but not multiple streams, for example, and therefore, EHT-LTF may be fixed to 1 symbol.

[0234] (Implementation method 3)

[0235] For example, when the terminal is allowed to preemptively send, the AP prepares hardware for receiving the normal (or non-preemptive) TB-PPDU (for example, hardware for preamble detection and processing) and hardware for receiving the preemptively sent signal, and receives the normal TB-PPDU and the preemptively sent data, respectively. Therefore, the hardware scale of the AP may become larger.

[0236] In this embodiment, for example, a method of reducing the hardware scale of the AP by setting (or limiting) the timing of preemptive transmission will be described.

[0237] The wireless communication system according to this embodiment may include AP 100 and terminal 200 similarly to Embodiment 1.

[0238] The structure of the AP 100 in this embodiment may be the same as that in the first embodiment.

[0239] The configuration of the terminal 200 of this embodiment may be the same as that of Embodiment 1. In the terminal 200 of this embodiment, for example, the operation of the preemption transmission control unit 204 may be different from that of Embodiment 1.

[0240] The preemptive transmission control unit 204 controls transmission of preemptive transmission data (eg, urgent data) within the length of time notified by the trigger frame, based on preempted resource information included in the preemption-related information input from the trigger frame determination unit 203 .

[0241] In addition, for example, when the trigger frame includes the transmission conditions as described in Embodiment 1 (for example, transmittable TID, length, transmission timing, etc.), the preemptive transmission control unit 204 can control the preemptive transmission according to the transmission conditions.

[0242] In addition, the preemptive transmission control unit 204 sets (for example, limits) the timing of preemptive transmission. For example, the preemptive transmission control unit 204 may also set the transmission timing of the preemptive signal based on the transmission timing of the TB-PPDU indicated by the trigger frame. It should be noted that an example of a method for setting the timing of preemptive transmission will be described later.

[0243] The preemption transmission control unit 204 outputs information for transmitting the preemption data to the transmission signal generation unit 205 .

[0244] Next, an example of a method for setting the timing of preemptive transmission will be described. It should be noted that the following transmission timing setting methods may be combined.

[0245] <Setting method 1>

[0246] Fig. 22 This is a diagram showing an example of setting the timing of preemptive transmission in setting method 1.

[0247] like Fig. 22As shown, the preemption signal may be set to be transmitted at a timing later than the U-SIG symbol of the TB-PPDU (e.g., the normal TB-PPDU) indicated by the trigger frame (or, later than the pre-EHT modulation field), but cannot be transmitted at a timing before the U-SIG symbol. For example, the preemption signal may be set to be transmitted at a timing later than the EHT-related symbol (e.g., the EHT-STF symbol) of the TB-PPDU indicated by the trigger frame, but cannot be transmitted at a timing earlier than the EHT-related symbol.

[0248] Here, the FFT / DFT sizes are different between the pre-EHT modulation field and the EHT modulation field, and therefore, the AP 100 may have another hardware structure for performing FFT / DFT processing on the signals of each field.

[0249] At this time, if Fig. 22 As shown, by preempting transmission at a later timing than the U-SIG symbol of the normal TB-PPDU, AP100 can make the hardware used for receiving and processing (signal detection, FFT / DFT, etc.) for the L-STF to U-SIG of the pre-EHT modulation field signal common between the TB-PPDU and the preempted PPDU in the receiver structure. Fig. 22 In the example shown, AP100 starts receiving L-STF to U-SIG of preemptive PPDU at least after receiving L-STF to U-SIG of TB-PPDU. Thus, AP100 can perform receiving processing of both TB-PPDU and preemptive PPDU using hardware for general receiving processing for pre-EHT modulation fields, for example.

[0250] Therefore, according to setting method 1, the hardware scale of the AP 100 can be reduced.

[0251] It should be noted that whether or not to apply the setting (or restriction) of the timing of preemptive transmission may be controlled based on the capability information of the AP 100 .

[0252] As an example, the capability information of AP 100 may include a flag indicating whether to set (or restrict) the timing of preemptive transmission after the U-SIG symbol of the TB-PPDU. For example, when the flag is 0 (for example, when there is no restriction), the terminal 200 can preempt transmission before the U-SIG symbol or after the U-SIG symbol. In addition, when the flag is 1 (for example, when there is a restriction), the terminal 200 cannot preempt transmission before the U-SIG symbol, but can preempt transmission after the U-SIG symbol.

[0253] It should be noted that the timing of preempting transmission is not limited to the method based on the timing of the U-SIG codeword (or, EHT-STF codeword). For example, it may also be a structure in which the timing of preempting transmission is set (or limited) based on the timing later than the U-SIG codeword (for example, the timing after EHT-LTF) based on the processing structure of the hardware of AP100.

[0254] <Setting method 2>

[0255] Fig.23 This is a diagram showing an example of setting the timing of preemptive transmission in setting method 2.

[0256] In setting method 2, if Fig.23 As shown, the timing of the preemption transmission can be set (or limited) in a manner that the symbol timing of the EHT modulation field (or the boundary of the OFDM symbol) is consistent between the preemption transmission and the transmission of the TB-PPDU. For example, the preemption signal can be sent in accordance with the symbol timing of the TB-PPDU indicated by the trigger frame.

[0257] As a result, AP100 can receive and process the codewords of the EHT modulation field of the TB-PPDU and the codewords of the preempted EHT modulation field together. Therefore, for the EHT modulation field, the received FFT / DFT processing can be made common, thereby reducing the hardware scale of AP100.

[0258] It should be noted that whether or not to apply the setting (or restriction) of the timing of preemptive transmission may be controlled based on the capability information of the AP 100 .

[0259] As an example, the capability information of the AP 100 may include a flag indicating whether to coordinate the symbol timing of the EHT modulation field of the preempted transmission with the symbol timing of the EHT modulation field of the TB PPDU (for example, whether to restrict the preempted transmission timing). For example, when the flag is 0 (for example, when not restricted), the terminal 200 can perform preemptive transmission without relying on the symbol timing of the TB-PPDU. In addition, for example, when the flag is 1 (for example, when restricted), the terminal 200 can perform preemptive transmission in coordination with the symbol timing of the EHT modulation field of the TB PPDU.

[0260] The above describes an example of setting the timing of preemptive transmission.

[0261] It should be noted that, although the preempted PPDU format is described in this embodiment as being the same format as the TB-PPDU, the preempted PPDU format is not limited thereto. For example, the preempted PPDU format may also be the preempted format described in Embodiment 2. According to the preempted format, the AP 100 may not perform the reception process of the pre-EHT modulation field in the preempted reception process. Thus, in the AP 100, hardware for receiving the pre-EHT modulation field may not be required in the preempted reception process.

[0262] (Variations of Embodiments 1 to 3)

[0263] (1) It is also possible that some of the trigger types notified by the general information field of the trigger frame do not allow preemptive transmission, while other trigger types allow preemptive transmission.

[0264] For example, ACK, RTS or clear to send (CTS) controlled by trigger types such as multi-user block ack request (MU-BAR), multi-user request to send (MU-RTS), and group cast with retries (GCR)-MU-BAR are important information for wireless control. Therefore, a trigger frame with a trigger type such as MU-BAR, MU-RTS or GCR-MU-BAR may not allow preemptive transmission. For example, a trigger frame with a trigger type different from MU-BAR, MU-RTS and GCR-MU-BAR may also allow preemptive transmission.

[0265] (2) Alternatively, the capability information of AP100 (for example, the capability of allowing the power notified by the target RSSI (Received Signal Strength Indicator) to exceed X dB) may be notified to the terminal 200, and the terminal 200 may decide whether to perform preemptive transmission and the power of the preemptive transmission based on the capability information.

[0266] X may be specified in the specification, or may be notified to the terminal 200 by control information such as a beacon.

[0267] For example, when the difference in received power between the received power of the preemption signal and the received power of the signal of the non-preemption TB-PPDU is large (for example, when the difference is greater than a threshold), the AP100 may not be able to correctly receive the signal depending on the capability of the AP100. Therefore, the preemption transmission may also be controlled based on the power variation calculated from the target received power according to the capability of the AP100. Thus, it is possible to suppress the situation where the AP100 cannot correctly decode the preemption signal due to the influence of the received power difference between the preemption and non-preemption.

[0268] (3) A non-preemptive TB-PPDU may not be sent in the resources allocated for preemption. The terminal 200 that sends the non-preemptive TB-PPDU can distinguish (or determine) the resources to be sent for preemption by, for example, decoding another user information field different from the user information field corresponding to the terminal 200 (for example, the user information field of AID=2008 in the case of resource notification example 1).

[0269] Therefore, the terminal 200 may not send data (e.g., non-preemptive TB-PPDU) in resources where preemption may occur. Thus, the interference caused by the non-preemptive TB-PPDU to the preemptive PPDU can be eliminated, thereby improving the reception quality of the preemptive signal.

[0270] In addition, for example, information related to whether the terminal 200 sending the non-preemptive TB-PPDU can send data in the preempted resources can also be notified to the terminal 200 by the trigger frame or beacon (for example, 0: can send, 1: cannot send).

[0271] (4) It is also possible to send non-preemptive transmission to the terminal 200 (for example, Figure 8 STA 1), and terminal 200 that performs preemptive transmission (for example, Figure 8 STA 2) allocates different resources (for example, RU or stream, etc.), and uses user multiplexing method (ULOFDMA or UL MU-MIMO, etc.) to multiplex the signals between the terminal 200 performing preemptive transmission and the terminal 200 performing non-preemptive transmission.

[0272] In this case, control that allows delay of start timing of preemptive transmission or cancellation of preemptive transmission may be applied to terminal 200 that performs preemptive transmission. Resources can be made orthogonal or quasi-orthogonal between preemptive transmission and non-preemptive transmission, thereby reducing interference.

[0273] In addition, when the user multiplexing method is used, different stream numbers may be respectively allocated to the terminal 200 performing non-preemptive transmission and the terminal 200 performing preemptive transmission in the trigger frame. For example, different stream numbers may be allocated to the terminal 200 performing non-preemptive transmission and the terminal 200 performing preemptive transmission in the SS allocation subfield of the user information field. The terminal 200 performing preemptive transmission and the terminal 200 performing non-preemptive transmission may also determine the LTF length (for example, the number of symbols of the EHT-LTF) based on the total number of spatial streams including the allocation for the terminal 200 performing non-preemptive transmission and the allocation for the terminal 200 performing preemptive transmission.

[0274] In addition, when the user multiplexing method is used to multiplex the terminal 200 that performs preemptive transmission and the terminal 200 that performs non-preemptive transmission, the terminal 200 that performs preemptive transmission, for example, can also send the preamble of the TB PPDU and put aside the transmission of the data field when receiving the trigger frame containing the allocation specifying the preemption. The transmission of the preamble of the TB PPDU can be performed at the same timing as the non-preemptive transmission, or a certain delay can be allowed compared with the case of non-preemptive transmission. For example, the AP100 can also use the EHT-LTF to perform channel estimation for the terminal 200 that may receive the preamble part (for example, not receive the data part) and perform preemptive transmission. The terminal 200 that performs preemptive transmission can also start sending the data field when preemptive transmission data occurs. As a result, with respect to the preamble, resources can be made orthogonal or quasi-orthogonal between the terminal 200 that performs preemptive transmission and the terminal 200 that performs non-preemptive transmission, thereby reducing interference.

[0275] It should be noted that, for example, the terminal 200 may retransmit all or part of the preamble before transmitting the data field. By retransmitting the preamble, the AP 100 can detect the timing of the data field.

[0276] (Implementation 4)

[0277] In Embodiments 1 to 3, a preemption control method related to an uplink signal (eg, an uplink OFDM signal) controlled by a trigger frame is described. In this embodiment, a preemption control method related to a downlink signal (eg, a downlink OFDM signal) is described.

[0278] Fig.24 FIG. 1 is a diagram showing an example of preemptive transmission in a downlink. Fig.24 In the example shown, the AP has preempted downlink data (e.g., emergency data) during the transmission of downlink data (e.g., MU PPDU) to STA 1. In this case, Fig.24As shown, the AP can overwrite the downlink PPDU sent to STA 1 by sending the preemption data sent to a different STA (for example, STA 2). Fig.24 In the example shown, the AP may preemptively transmit in a portion of the transmission frequency band of the downlink PPDU of STA 1.

[0279] exist Fig.24 In the present invention, STA 1 uses all data received within the length of the downlink PPDU sent to STA 1 (for example, including the preempted data) for reception processing (for example, decoding processing) without realizing that the AP is performing a preemptive transmission (for example, a portion of the transmission signal sent to STA 1 is not sent), so the reception performance may be degraded.

[0280] In this embodiment, for example, the AP can notify the terminal that preemption has occurred in the downlink (for example, a portion of the non-preemptive transmitted signal is not transmitted). Thus, the terminal can improve reception performance by not applying the signal of the preempted interval to the decoding process.

[0281] Fig.25 is a diagram showing an example of a format of a downlink OFDM signal (e.g., EHT MU PPDU). Figure 1 ) is that there is an EHT-SIG field, which contains control information (e.g., resource allocation information, etc.) of a signal transmitted in a downlink.

[0282] [Structure of wireless communication system]

[0283] The wireless communication system of this embodiment may include, for example, Fig.26 The AP300 and Fig. 27 The terminal (STA) 400 shown. In the wireless communication system, at least one of the AP300 and the terminal 400 may also exist more than two. The AP300 may, for example, send preemptive data (e.g., emergency data) to the terminal 400. The AP100 may, for example, be an AP supporting EHT or EHT enhancement. For example, in the case of communicating with an EHT enhanced terminal, the AP100 as the communication object may support EHT enhancement.

[0284] In addition, the terminal 400 may be, for example, an EHT terminal or an EHT enhanced terminal. For example, the terminal 400 separates data addressed to each terminal 400 from a received signal based on resources allocated to each terminal 400, and performs reception processing.

[0285] In addition, the AP 300 may have backward compatibility. For example, the AP 300 supporting EHT enhancement may communicate with the HE terminal and the EHT terminal using a trigger frame in addition to communicating with the EHT enhanced terminal.

[0286] [Structural example of AP300]

[0287] Fig.26 This is a block diagram showing a configuration example of the AP300. Fig.26 The AP 300 shown may include, for example, a preemption transmission control unit 301 , a scheduling unit 302 , a preemption identifier generating unit 303 , a transmission signal generating unit 304 , a wireless transceiver unit 305 , and a received signal demodulation / decoding unit 306 .

[0288] For example, the preemptive transmission control unit 301 and the scheduling unit 302 may be included in an access control unit (eg, a MAC processing unit).

[0289] For example, when preemptive data (eg, urgent data) is detected to occur during the transmission period of downlink data, the preemptive transmission control unit 301 instructs the scheduling unit 302 to allocate resources for preemptive transmission (or indicates that preemptive transmission has occurred).

[0290] The scheduling unit 302 may perform scheduling for the terminal 400 , for example.

[0291] For example, the scheduling unit 302 allocates downlink resources to the terminal 400 that performs existing (or, normal) MU-PPDU transmission (for example, non-preemptive transmission) without preemptive transmission, determines information for identifying the terminal 400 (for example, terminal ID), wireless resource information (allocated frequency band, MCS, etc.) of each terminal 400, and outputs the determined information to the transmission signal generating unit 304. In addition, in this case, the scheduling unit 302 outputs information indicating that preemption does not occur at the current time point to the preemption identifier generating unit 303.

[0292] In addition, when the preemption transmission control unit 301 notifies that preemption has occurred (when allocation of preemption transmission resources is instructed), the scheduling unit 302 allocates preempted downlink resources, determines the terminal ID and preempted wireless resource information (allocated frequency band, etc.), and outputs the determined information to the transmission signal generating unit 304. In addition, in this case, the scheduling unit 302 outputs information indicating that preemption has occurred (for example, including frequency resources and time resources where preemption has occurred) to the preemption identifier generating unit 303.

[0293] The preemption identifier generation unit 303 generates control information (e.g., a preemption identifier) ​​for notifying the occurrence of preemption, based on information (e.g., including frequency resources and time resources where preemption occurs) input from the scheduling unit 302. The preemption identifier generation unit 303 outputs the generated information to the transmission signal generation unit 304. It should be noted that an example of processing in the preemption identifier generation unit 303 will be described later.

[0294] The transmission signal generating unit 304 performs error correction coding and modulation processing on the downlink control information, downlink data and the information input from the preemption identifier generating unit 303 based on the wireless resource information input from the scheduling unit 302 , and outputs the modulated data signal to the wireless transceiver unit 305 .

[0295] For example, at the timing of preemption, the transmission signal generation unit 304 may overwrite the preempted data with the non-preempted data in the frequency resources and time resources for preempted transmission input from the scheduling unit 302 .

[0296] It should be noted that when the modulated data signal is an OFDM signal, AP300 (for example, the transmission signal generating unit 304) can map the modulated signal to a specified frequency resource, perform IFFT / IDFT processing to convert it into a time waveform, and add a CP, thereby forming an OFDM signal.

[0297] The wireless transceiver 305 performs wireless transmission processing such as D / A conversion and up-conversion to a carrier frequency on the modulated signal input from the transmission signal generator 304, and transmits the signal after the wireless transmission processing to the terminal 400 via the antenna. In addition, the wireless transceiver 305 receives a signal transmitted from the terminal 400 via the antenna, performs wireless reception processing such as down-conversion to a baseband frequency and A / D conversion on the received signal, and outputs the signal after the wireless reception processing to the reception signal demodulation / decoding unit 306.

[0298] The received signal demodulation / decoding unit 306 performs demodulation and decoding processing on the signal input from the wireless transceiver unit 305, and obtains control information and data such as ACK sent from the terminal 400. For example, the received signal demodulation / decoding unit 306 can output control information such as ACK to the scheduling unit 302. It should be noted that when the signal input to the received signal demodulation / decoding unit 306 is an OFDM signal, the AP 300 (for example, the received signal demodulation / decoding unit 306) can perform CP removal processing and FFT / DFT processing.

[0299] [Configuration Example of Terminal 400]

[0300] Fig. 27 It is a block diagram showing a configuration example of the terminal 400 . Fig. 27The terminal 400 shown may include, for example, a wireless transceiver unit 401 , a preemption identifier demodulation / decoding unit 402 , a received signal demodulation unit 403 , a received signal decoding unit 404 , and a transmission signal generating unit 405 .

[0301] The wireless transceiver 401 receives the received signal using, for example, an antenna, performs wireless reception processing such as down-conversion and A / D conversion on the received signal, and outputs the signal after the wireless reception processing to the preemption identifier demodulation / decoding unit 402 and the received signal demodulation unit 403. In addition, the wireless transceiver 401 performs wireless transmission processing such as up-conversion and D / A conversion on the signal input from the transmission signal generation unit 405, and transmits the signal after the wireless transmission processing from the antenna.

[0302] The preemption identifier demodulation / decoding unit 402 demodulates and decodes data in a field including a preemption identifier of reception data input from the wireless transmission / reception unit 401 , for example, and outputs information related to preemption of transmission resources to the reception signal decoding unit 404 .

[0303] The received signal demodulation unit 403 performs demodulation processing on the received data input from the wireless transceiver unit 401, and outputs the demodulated signal to the received signal decoding unit 404. It should be noted that when the signal input to the received signal demodulation unit 403 is an OFDM signal, the terminal 400 (for example, the received signal demodulation unit 403) can perform CP removal processing and FFT / DFT processing, for example.

[0304] The received signal decoding unit 404, for example, based on the information related to the preempted transmission resource input from the preemption identifier demodulation / decoding unit 402, excludes data of resources (for example, preempted transmission resources) that do not transmit signals to the terminal 400 from the demodulated data sequence input from the received signal demodulation unit 403, and performs decoding processing on the data to extract the received data. In addition, the received signal decoding unit 404 outputs information indicating whether the data decoding is successful (for example, a decoding result) to the transmission signal generation unit 405, for example.

[0305] In addition, when performing a preemptive transmission to the terminal 400, the received signal decoding unit 404 extracts the preemptive signal from the demodulated data sequence input from the received signal demodulation unit 403 based on the resource information of the preemptive transmission, and decodes the data to extract the preemptive data.

[0306] The transmission signal generating unit 405 generates a transmission signal such as ACK based on the decoding result input from the received signal decoding unit 404. The transmission signal generating unit 405 performs error correction coding and modulation processing on the generated transmission signal, and outputs the modulated data signal to the wireless transceiver unit 401. It should be noted that when the modulated signal is an OFDM signal, the terminal 400 (for example, the transmission signal generating unit 405) can perform IFFT / IDFT processing and add CP after mapping the modulated signal to the frequency resource, thereby forming an OFDM signal.

[0307] [Example of generating a preemption identifier]

[0308] Next, an example of control information (for example, preemption identifier) ​​generated in the preemption identifier generation unit 303 will be described.

[0309] AP300, for example, uses control information (preemption identifier) ​​to notify terminal 400 that preemption has occurred (for example, part of the non-preemptively transmitted signal is not transmitted). Thus, terminal 400 can improve reception performance by, for example, not applying the signal of the preempted section to the non-preemptively transmitted decoding process.

[0310] An example of the format of the preemption identifier is shown below.

[0311] <Preemption Identifier Format Example 1>

[0312] In the preemption identifier format example 1, it is possible to notify whether preemption occurs in each OFDM symbol constituting the data part (or whether data is transmitted to the relevant terminal 400).

[0313] Fig.28 The format of the preemption identifier in the preemption identifier format example 1 is shown.

[0314] exist Fig.28 In the example of , a 1-bit preemption identifier may be set for each OFDM symbol #1 to #N. For example, when preemption occurs in each OFDM symbol (for example, when data is not sent to the terminal 400), the preemption identifier is set to 1, and when preemption does not occur (for example, when data is sent to the terminal 400), the preemption identifier is set to 0.

[0315] Thus, terminal 400 can determine whether preemption occurs in the data portion (or whether data addressed to terminal 400 is transmitted) for each OFDM symbol.

[0316] <Preemption Identifier Format Example 2>

[0317] In the preemption identifier format example 2, whether preemption occurs in each of a plurality of OFDM symbols (for example, a group) among the OFDM symbols constituting the data part (or whether data is transmitted to the relevant terminal 400) can be notified at once.

[0318] Fig.29 The format of the preemption identifier in the preemption identifier format example 2 is shown.

[0319] exist Fig.29 In the example of , a 1-bit preemption identifier may be set in units of two OFDM symbols among OFDM symbols #1 to #N. For example, when preemption occurs in one of the two OFDM symbols corresponding to 1 bit (for example, when data is not sent to the relevant terminal 400), the preemption identifier may be set to 1. In addition, for example, when preemption does not occur in both of the two OFDM symbols corresponding to 1 bit (for example, when data is sent to the terminal 400), the preemption identifier may be set to 0.

[0320] Therefore, compared with the preemption identifier format example 1, the preemption identifier format example 2 can reduce the number of bits of the control information.

[0321] The above describes an example of the format of the preemption identifier.

[0322] It should be noted that the format of the preemption identifier is not limited to these formats, and may be other formats. Fig.28 and Fig.29 In the example, the number of bits allocated as the preemption identifier is not limited to 1 bit, but may be 2 bits or more. In addition, the unit of the OFDM symbol corresponding to the preemption identifier is not limited to 1 symbol or 2 symbols, but may be 3 symbols or more. In addition, the format example 1 and the format example 2 may be applied in combination.

[0323] For example, the AP 300 may send a preemption identifier after the data portion of the downlink PPDU. For example, the terminal 400 may decode the preemption identifier after receiving the data portion, and determine (e.g., switch, change) the decoding process of the data portion according to the set value of the preemption identifier. For example, in format example 1, when the preemption identifier = 0, 0, 0, 0, 1, 1, 0, 0, 0, the terminal 400 may perform decoding processing on OFDM symbols #5 and #6 while reducing the likelihood of error correction.

[0324] An example of a format for notifying a preemption identifier in a downlink PPDU is described below.

[0325] <PPDU format example 1>

[0326] Fig.30It shows the format of PPDU in PPDU format example 1.

[0327] like Fig.30 As shown, a preemption identifier field (preemption indicator field) for notifying a preemption identifier may be set after the data part (data field) of a downlink PPDU (eg, MU PPDU).

[0328] For example, a fixed value (eg, BCC (Block Check Character), QPSK (Quadrature Phase Shift Keying), R=1 / 2) may also be applied as the coding / modulation scheme (eg, MCS) in the preemption identifier field.

[0329] In addition, for example, in the case of applying OFDMA, Fig.31 As shown, the preemption identifier sent to each terminal 400 may also be notified in each frequency band allocated to each terminal 400. For example, the duration of the preemption identifier may also be coordinated with the size of the preemption identifier sent to the terminal 400 with the longest duration among the terminals 400 multiplexed in OFDMA. For example, in order to adjust the size of the preemption identifier between the terminals 400, padding bits (for example, all 0s) may be added to adjust the size.

[0330] <PPDU format example 2>

[0331] The preemption identifier may be included in, for example, a PE (Packet Extension) field of a downlink PPDU. The AP 300 may send the preemption identifier in, for example, a PE field of a downlink PPDU.

[0332] In the existing standard, an arbitrary value can be set in the PE field. Therefore, by using the PE field to notify the preemption identifier, the overhead of the control information can be reduced.

[0333] The above describes an example of the PPDU format.

[0334] Thus, in this embodiment, AP300 sends a downlink PPDU containing control information (e.g., including whether preemptive transmission occurs) to terminal 400. The control information is control information related to resources used for preemptive transmission occurring during the transmission period of the downlink PPDU. Terminal 400 performs reception control of the preemptive signal based on the control information contained in the downlink PPDU.

[0335] Thus, for example, the terminal 400 can receive data (e.g., emergency data) generated during the period when the AP 300 sends a signal to other terminals based on the control information contained in the downlink PPDU. Thus, according to this embodiment, even in the case of preemptive transmission, the delay can be reduced, thereby improving the efficiency of signal transmission control in wireless communication.

[0336] In the above, each embodiment of the present disclosure has been described.

[0337] It should be noted that in the above-mentioned embodiments, the structure of the trigger frame, the structure of the general information field, the user information field and the special user information field in the trigger frame, and the structure of the uplink PPDU or the downlink PPDU are not limited to the above-mentioned examples. For example, it may be other structures after at least one of the addition of other fields and the deletion of part of the fields is performed, or it may be other structures after at least one of the addition of other subfields and the deletion of part of the subfields is performed in the above-mentioned fields.

[0338] In addition, in the above-mentioned embodiment, although the format based on 11be is described as an example, the format of an embodiment of the present disclosure is not limited to the format of 11be. An embodiment of the present disclosure can also be applied to the next generation standard of IEEE 802.11p as an in-vehicle standard, namely IEEE 802.11bd (NGV (Next Generation V2X, next generation vehicle wireless communication technology)).

[0339] (Replenish)

[0340] The information indicating whether the terminal (for example, terminal 200 or terminal 400) supports the functions, actions or processing shown in the above-mentioned embodiments can also be sent (or notified) by the terminal to the AP (for example, AP100 or AP300) as the capability information or capability parameter of the terminal.

[0341] The capability information may also include the following information element (IE: Information Element), which alone indicates whether the terminal 200 supports at least one of the functions, actions, and processes shown in the above embodiments. Alternatively, the capability information may also include the following information element, which indicates whether the terminal supports a combination of two or more of the functions, actions, and processes shown in the above embodiments. An information element may also be simply referred to as an "element".

[0342] For example, the AP may determine (or, decide or assume) the functions, actions or processes supported (not supported) by the source terminal of the capability information based on the capability information received from the terminal. The AP may implement actions, processes or controls corresponding to the determination result based on the capability information. For example, the AP may control preemption based on the capability information received from the terminal.

[0343] It should be noted that the terminal does not support a part of the functions, actions or processes shown in the above embodiments, which can also be replaced by limiting such a part of the functions, actions or processes in the terminal. For example, information or requests related to such limitations can also be notified to the AP.

[0344] The information related to the capabilities or limitations of the terminal may be defined in the standard, for example, or may be implicitly notified to the AP by being associated with information known to the AP or information sent to the AP.

[0345] The present disclosure can be implemented by software, hardware or software in cooperation with hardware. Each functional block used in the description of the above-mentioned embodiments is partially or entirely implemented as an LSI (Large Scale Integration) as an integrated circuit, and each process described in the above-mentioned embodiments may also be partially or entirely controlled by an LSI or a combination of LSIs. LSI may be composed of individual chips, or may be composed of one chip in a manner that includes part or all of the functional blocks. LSI may also include input and output of data. LSI may also be referred to as "IC (Integrated Circuit)", "System LSI", "Super LSI", "Ultra LSI" depending on the degree of integration.

[0346] The method of integrated circuitization is not limited to LSI, and can also be implemented by a dedicated circuit, a general-purpose processor or a dedicated processor. In addition, an FPGA (Field Programmable Gate Array) that can be programmed after LSI manufacturing, or a reconfigurable processor (Reconfigurable Processor) that can reconfigure the connection or setting of the circuit block inside the LSI can also be used. The present disclosure can also be implemented as digital processing or analog processing.

[0347] Furthermore, if integrated circuit technology that replaces LSI emerges as semiconductor technology advances or other technologies are derived, it is of course possible to use this technology to achieve integration of functional blocks. There is also the possibility of applying biotechnology, etc.

[0348] The present disclosure can be implemented in all kinds of devices, equipment, and systems (collectively referred to as "communication devices") with communication functions. The communication device may also include a wireless transceiver and a processing / control circuit. The wireless transceiver may also include a receiving unit and a transmitting unit, or perform the functions of these parts. The wireless transceiver (transmitting unit, receiving unit) may also include an RF (Radio Frequency) module and one or more antennas. The RF module may also include an amplifier, an RF modulator / demodulator, or a device similar to these. Non-limiting examples of communication devices include: phones (mobile phones, smart phones, etc.), tablets, personal computers (PCs) (laptops, desktops, notebook computers, etc.), cameras (digital cameras, digital video cameras, etc.), digital players (digital audio / video players, etc.), wearable devices (wearable cameras, smart watches, tracking devices, etc.), game consoles, e-book readers, telehealth / telemedicine (telehealth / medical prescription) equipment, vehicles or transportation vehicles with communication functions (cars, airplanes, ships, etc.), and combinations of the above-mentioned various devices.

[0349] Communication devices are not limited to portable or mobile devices, but also include all kinds of devices, equipment, and systems that cannot be carried or fixed. For example, they include: smart home devices (home appliances, lighting equipment, smart meters or meters, control panels, etc.), vending machines, and all other "things" that can exist on the IoT (Internet of Things) network.

[0350] The communication includes data communication performed by a cellular system, a wireless LAN (Local Area Network) system, a communication satellite system, etc., and also includes data communication performed by a combination of these systems.

[0351] In addition, the communication device also includes devices such as controllers or sensors connected or linked to the communication device that performs the communication function described in the present invention. For example, it includes a controller or sensor that generates a control signal or data signal used by the communication device that performs the communication function of the communication device.

[0352] In addition, the communication device includes infrastructure equipment that communicates with the above-mentioned non-limiting various devices or controls the above-mentioned various devices, such as base stations, access points, and all other devices, equipment, and systems.

[0353] An access point according to an embodiment of the present disclosure includes: a control circuit that generates control information related to resources used for transmission of a second signal that occurs during a transmission period of a first signal; and a transmission circuit that transmits the control information.

[0354] In one embodiment of the present disclosure, the control information is included in a user information field of a trigger frame.

[0355] In one embodiment of the present disclosure, an association ID (AID) of the user information field containing the control information is a value associated with the transmission of the second signal.

[0356] In one embodiment of the present disclosure, in the trigger frame, the plurality of user information fields include information indicating whether the user information field is related to the transmission of the second signal.

[0357] In one embodiment of the present disclosure, an association ID (AID) of the user information field related to the transmission of the second signal is a value of an AID of at least one terminal that can transmit the second signal.

[0358] In one embodiment of the present disclosure, a condition related to whether to allow sending the second signal is specified and notified to the terminal by the trigger frame, or notified to the terminal by a signal different from the trigger frame.

[0359] In one embodiment of the present disclosure, the condition is based on at least one of a service category of the second signal, a duration of the second signal, and a transmission timing of the second signal.

[0360] In one embodiment of the present disclosure, the information related to the condition is included in at least one of the UL-EHT MCS subfield, the SS allocation subfield, the UL target received power subfield, the trigger dependent user information subfield and the reserved subfield of the special user information field of the trigger frame.

[0361] In one embodiment of the present disclosure, the control information is included in a general information field of a trigger frame.

[0362] In one embodiment of the present disclosure, a format of the second signal is different from a format of the first signal, and a preamble of the second signal is transmitted within an allocated resource of the second signal indicated by a trigger frame.

[0363] In one embodiment of the present disclosure, the sending timing of the second signal is set based on the sending timing of the first signal.

[0364] In one embodiment of the present disclosure, the second signal is transmitted at a timing after an extremely high throughput (EHT)-related symbol of the first signal.

[0365] In one embodiment of the present disclosure, the second signal is transmitted in synchronization with the symbol timing of the first signal.

[0366] In one embodiment of the present disclosure, the first signal and the second signal are downlink data, the control information is included in the first signal, and indicates that the second signal is generated during a transmission period of the first signal.

[0367] In one embodiment of the present disclosure, the field of the control information is set after the data field of the first signal.

[0368] In one embodiment of the present disclosure, the control information is included in a packet extension (PE) field of the first signal.

[0369] A terminal of one embodiment of the present disclosure includes: a receiving circuit that receives control information, which is control information related to resources used for sending a second signal that occurs during a period of sending a first signal; and a control circuit that controls the sending or receiving of the second signal based on the control information.

[0370] In a communication method according to an embodiment of the present disclosure, an access point performs the following processing: generates control information related to resources used for transmission of a second signal occurring during a transmission period of a first signal; and transmits the control information.

[0371] In a communication method of one embodiment of the present disclosure, a terminal performs the following processing: receiving control information, which is control information related to resources used for sending a second signal that occurs during a period of sending a first signal; and controlling the sending or receiving of the second signal based on the control information.

[0372] The disclosed contents of the specification, drawings, and abstract contained in the Japanese patent application No. 2022-096537 filed on June 15, 2022 are incorporated herein by reference in their entirety.

[0373] Industrial Applicability

[0374] One embodiment of the present disclosure is useful for a wireless communication system.

[0375] Description of Reference Numerals

[0376] 100, 300 AP

[0377] 101, 302 Dispatching Department

[0378] 102 Trigger frame generation unit

[0379] 103, 205, 304, 405 transmission signal generating unit

[0380] 104, 201, 305, 401 wireless transceiver

[0381] 105, 202, 306 received signal demodulation / decoding unit

[0382] 200, 400 terminals

[0383] 203 Trigger frame determination unit

[0384] 204, 301 Preemption Send Control Unit

[0385] 303 Preemption Identifier Generation Unit

[0386] 402 Preemption Identifier Demodulation / Decoding Unit

[0387] 403 Received signal demodulation unit

[0388] 404 Received signal decoding unit

Claims

1. An access point, characterized in that: include: A control circuit generates control information related to resources used for transmission of a second signal occurring during a transmission period of the first signal; as well as The sending circuit sends the control information.

2. The access point according to claim 1, wherein: The control information is included in the user information field of the trigger frame.

3. The access point according to claim 2, wherein: The association ID (AID) of the user information field including the control information is a value associated with the transmission of the second signal.

4. The access point according to claim 2, wherein: In the trigger frame, the plurality of user information fields include information indicating whether the user information field is related to the transmission of the second signal.

5. The access point according to claim 4, wherein: The AID of the user information field related to the transmission of the second signal is a value of the AID of at least one terminal that can transmit the second signal.

6. The access point of claim 2, wherein: A condition related to whether to allow the second signal to be sent is defined and notified to the terminal by the trigger frame, or notified to the terminal by a signal different from the trigger frame.

7. The access point according to claim 6, wherein: The condition is based on at least one of a traffic class of the second signal, a duration of the second signal, and a transmission timing of the second signal.

8. The access point according to claim 6, wherein: The information related to the condition is included in at least one of the uplink very high throughput modulation and coding scheme subfield of the user information field of the trigger frame, namely, the UL-EHT MCS subfield, the SS allocation subfield, the UL target received power subfield, the trigger dependent user information subfield, and the reserved subfield of the special user information field.

9. The access point of claim 1, wherein: The control information is included in the general information field of the trigger frame.

10. The access point of claim 1, wherein: The format of the second signal is different from the format of the first signal, The preamble of the second signal is transmitted within the allocated resources of the second signal indicated by the trigger frame.

11. The access point of claim 1, wherein: The transmission timing of the second signal is set based on the transmission timing of the first signal.

12. The access point of claim 11, wherein: The second signal is transmitted at a timing after a symbol of the first signal related to extremely high throughput (EHT).

13. The access point of claim 11, wherein: The second signal is transmitted in synchronization with the symbol timing of the first signal.

14. The access point of claim 1, wherein: The first signal and the second signal are downlink data, The control information is included in the first signal, and indicates that the second signal is generated during a transmission period of the first signal.

15. The access point of claim 14, wherein: The field for the control information is set after the data field of the first signal.

16. The access point of claim 14, wherein: The control information is included in the packet extension field, ie, the PE field, of the first signal.

17. A terminal, characterized in that: include: A receiving circuit receives control information related to resources used for transmission of a second signal occurring during a transmission period of the first signal; as well as The control circuit controls the sending or receiving of the second signal based on the control information.

18. A communication method, characterized in that: The access point performs the following processing: generating control information related to resources used for transmission of a second signal occurring during a transmission period of the first signal; and The control information is sent.

19. A communication method, characterized in that: The terminal performs the following processing: receiving control information related to resources used for transmission of a second signal occurring during a transmission period of the first signal; as well as Based on the control information, the sending or receiving of the second signal is controlled.

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