Extended range physical layer protocol data unit (PPDU)

Abstract

The invention provides an extended range physical layer protocol data unit. Methods, systems, and computer-readable media are disclosed for performing operations including: generating an Extended Range Physical Layer Protocol Data Unit (ER-PPDU) for transmission to a receiver, the ER-PPDU including an ultra high reliability Extended Range Long Training Field (UHR-ER LTF) and an ultra high reliability Extended Range Signal Field (UHR-ER SIG); and transmitting the ER-PPDU to the receiver, wherein at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated two or more times in a time domain or a frequency domain.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 525,636 filed on July 7, 2023 and U.S. Provisional Patent Application No. 63 / 547,477 filed on November 6, 2023, each of which is incorporated herein by reference in its entirety. Background Art

[0003] Many electronic devices communicate with each other using wireless local area networks (WLANs), such as those based on communication protocols for wireless local area networks (also known as "Wi-Fi") that conform to Institute of Electrical and Electronics Engineers (IEEE) standards (e.g., IEEE 802.11 standards). A WLAN typically includes an access point that provides one or more stations (STAs) with access to another network, such as the Internet. There are many generations of the IEEE 802.11 standard, including 802.11ax (Wi-Fi 6) and 802.11be (Wi-Fi 7).

[0004] IEEE 802.11 is a packet-based protocol. According to this protocol, a transmitter (e.g., an access point (AP)) encapsulates control information or user data into a protocol data unit (PDU) in a physical layer convergence protocol (PLCP). A PLCP PDU (PPDU) includes a preamble and a data field, among other fields. After generating the PPDU, the access point can transmit the PPDU to a station connected to the access point. Communication from an access point to a station is called a downlink, and communication from a station to an access point is called an uplink. Summary of the invention

[0005] This disclosure describes techniques for improving uplink link budget and reliability of uplink transmissions in Wi-Fi and other wireless communication networks.

[0006] In general, in a first aspect, a method includes: generating an extended range physical layer protocol data unit (ER-PPDU) for transmission to a receiver, the ER-PPDU including an ultra high reliability extended range long training field (UHR-ER-LTF) and an ultra high reliability extended range signal field (UHR-ER-SIG); and transmitting the ER-PPDU to the receiver, wherein at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated two or more times in the time domain or the frequency domain.

[0007] In a second aspect that can be combined with the first aspect, the ER-PPDU also includes a legacy short training field (L-STF), a legacy long training field (L-LTF), and one or more additional fields between the L-LTF and the UHR-ER-LTF, the one or more additional fields including at least one of a legacy signal field (L-SIG), a repeated legacy signal field (RL-SIG), a universal signal field (U-SIG), or an ultra-high reliability short training field (UHR-STF).

[0008] In a third aspect combinable with the first aspect or the second aspect, at least one of the L-STF or the L-LTF is power-boosted by 3 dB or more.

[0009] In a fourth aspect which may be combined with any one of the first to third aspects, the at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of an orthogonal frequency division multiplexing (OFDM) symbol.

[0010] In a fifth aspect which can be combined with any one of the first to fourth aspects, the at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of the OFDM symbol using every four subcarriers of the OFDM symbol.

[0011] In a sixth aspect which can be combined with any one of the first to fifth aspects, the OFDM symbol length including a guard interval is 16 microseconds.

[0012] In a seventh aspect that can be combined with any one of the first to sixth aspects, the ER-PPDU includes 52 frequency-tuned resource units and a channel bandwidth of 20 MHz, and at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of the OFDM symbol using every four subcarriers from subcarrier index -104 to subcarrier index 104.

[0013] In an eighth aspect which may be combined with any one of the first to seventh aspects, the at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated four times in the time domain or the frequency domain.

[0014] In a ninth aspect which may be combined with any one of the first to eighth aspects, the operation of the method includes obtaining data to be sent to the receiver, wherein the ER-PPDU further includes a data field including at least a portion of the data to be sent to the receiver.

[0015] In a tenth aspect which may be combined with any one of the first to ninth aspects, the data field is repeated two or more times in the time domain or the frequency domain.

[0016] In an eleventh aspect which may be combined with any one of the first to tenth aspects, the data field is modulated over the entire length of the OFDM symbol using every four subcarriers of the OFDM symbol.

[0017] In a twelfth aspect that can be combined with any one of the first to eleventh aspects, the operation of the method includes performing a center frequency offset (CFO) correction before sending the ER-PPDU to the receiver, wherein the residual CFO after performing the CFO correction is less than or equal to 15 kHz.

[0018] In a thirteenth aspect that may be combined with any one of the first to twelfth aspects, the operations of the method are performed by a non-access point station (non-AP STA).

[0019] In a fourteenth aspect that may be combined with any one of the first to thirteenth aspects, the operations of the method include: receiving an indication of a maximum size of the ER-PPDU from the receiver; and generating the ER-PPDU according to the maximum size.

[0020] In general, in a fifteenth aspect, a method includes: receiving an extended range physical layer protocol data unit (ER-PPDU) from a transmitter, the ER-PPDU including an ultra high reliability extended range long training field (UHR-ER-LTF) and an ultra high reliability extended range signal field (UHR-ER-SIG), wherein at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated two or more times in the time domain or the frequency domain; and processing the ER-PPDU to obtain information included in at least one of the UHR-ER-LTF or the UHR-ER-SIG.

[0021] In the sixteenth aspect that can be combined with the fifteenth aspect, the ER-PPDU also includes a legacy short training field (L-STF), a legacy long training field (L-LTF), and one or more additional fields between the L-LTF and the UHR-ER-LTF, the one or more additional fields including at least one of a legacy signal field (L-SIG), a repeated legacy signal field (RL-SIG), a universal signal field (U-SIG), or an ultra-high reliability short training field (UHR-STF), and the operation of the method also includes: processing the PPDU to obtain information included in the L-STF, the L-LTF, or at least one of the one or more additional fields.

[0022] In the seventeenth aspect combinable with the fifteenth aspect or the sixteenth aspect, at least one of the L-STF and the L-LTF is power-boosted by 3 dB or more.

[0023] In the eighteenth aspect that can be combined with any one of the fifteenth to seventeenth aspects, at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of an orthogonal frequency division multiplexing (OFDM) symbol using every four subcarriers of the OFDM symbol.

[0024] In the nineteenth aspect that can be combined with any one of the fifteenth to eighteenth aspects, the ER-PPDU includes 52 frequency-tuned resource units and a channel bandwidth of 20 MHz, and at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of the OFDM symbol using every four subcarriers from subcarrier index -104 to subcarrier index 104.

[0025] In the twentieth aspect which may be combined with any one of the fifteenth to nineteenth aspects, the at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated four times in the time domain or the frequency domain.

[0026] In the 21st aspect which can be combined with any one of the 15th to 20th aspects, the ER-PPDU includes a data field repeated two or more times in the time domain or the frequency domain, and the operation of the method also includes processing the ER-PPDU to obtain information included in the data field.

[0027] In a twenty-second aspect that may be combined with any one of the fifteenth to twenty-first aspects, the operation of the method includes performing a cross-correlation to detect a center frequency offset (CFO) of the ER-PPDU.

[0028] In the twenty-third aspect which can be combined with any one of the fifteenth to twenty-second aspects, a center frequency offset (CFO) of the ER-PPDU is corrected before transmission so that a residual CFO of the ER-PPDU is less than or equal to 15 kHz.

[0029] In the twenty-fourth aspect which may be combined with any one of the fifteenth to twenty-third aspects, the operations of the method are performed by an access point station (AP STA), and the transmitter is a non-access point station (non-AP STA).

[0030] Generally speaking, in aspect twenty-fifth, a method includes: sending a trigger request to a receiver, the trigger request indicating the size of data to be sent to the receiver; receiving a trigger from the receiver, the trigger indicating a duration for sending the data to the receiver, wherein the duration is determined based on the size of the data indicated in the trigger request; and generating a trigger-based physical layer protocol data unit (TB-PPDU) based in part on the duration, the TB-PPDU including the data to be sent to the receiver.

[0031] In a twenty-sixth aspect that may be combined with the twenty-fifth aspect, the operation of the method includes receiving a confirmation of the trigger request from the receiver, wherein the confirmation is received before receiving the trigger.

[0032] In the twenty-seventh aspect which may be combined with the twenty-fifth aspect or the twenty-sixth aspect, the operation of the method includes sending the TB-PPDU to the receiver.

[0033] In the twenty-eighth aspect which may be combined with any one of the twenty-fifth to twenty-seventh aspects, the TB-PPDU comprises a super-reliability TB-PPDU.

[0034] In aspect 29 which may be combined with any of aspects 25 to 28, the trigger request comprises an indication of one or more of a media access control (MAC) address, a site identifier, a queue size, access category information, or a packet type of the data to be sent.

[0035] In the thirtieth aspect which can be combined with any one of the twenty-fifth to twenty-ninth aspects, the trigger request is sent in response to the size of the data satisfying a threshold.

[0036] In the thirty-first aspect which may be combined with any one of the twenty-fifth to thirtieth aspects, the operation of the method is performed by a non-access point station (non-AP STA).

[0037] Generally speaking, in aspect thirty-second, a method includes: receiving a trigger request from a transmitter, the trigger request indicating the size of data to be sent by the transmitter; determining the duration of a trigger-based physical protocol data unit (TB-PPDU) based on the size of the data; and sending a trigger to the transmitter, the trigger indicating the duration of the TB-PPDU.

[0038] In a thirty-second aspect which may be combined with the thirty-first aspect, the operation of the method comprises sending a confirmation of the trigger request to the transmitter, wherein the confirmation is sent before sending the trigger.

[0039] In the thirty-third aspect which may be combined with the thirty-first aspect or the thirty-second aspect, the operation of the method includes receiving the TB-PPDU including the data, the TB-PPDU being generated based on the duration.

[0040] In the thirty-fourth aspect which can be combined with any one of the thirty-first to thirty-third aspects, the TB-PPDU is a super-reliability TB-PPDU.

[0041] In the thirty-fifth aspect which may be combined with any one of the thirty-first to thirty-fourth aspects, the operations of the method are performed by an access point (AP), and the transmitter is a non-access point station (non-AP STA).

[0042] In general, in a thirty-sixth aspect, a method includes receiving a non-high throughput physical protocol data unit (non-HT PPDU); and sending a control frame in response to the non-HT PPDU, the control frame including an ultra-high reliability extended range single user PPDU (UHR ER SU PPDU) format.

[0043] In a thirty-seventh aspect combinable with the thirty-sixth aspect, the non-HT PPDU includes a request to send (RTS), and the control frame including the UHR ER SU PPDU format includes a clear to send (CTS).

[0044] In the thirty-eighth aspect which can be combined with the thirty-sixth aspect or the thirty-seventh aspect, the control frame including the UHR ER SUPPDU format is transmitted in a repeated transmission mode over a bandwidth greater than or equal to 20 MHz.

[0045] In the thirty-ninth aspect which can be combined with any one of the thirty-sixth to thirty-eighth aspects, the control frame is transmitted using the UHR ER SU PPDU format according to an operation mode.

[0046] In the 40th aspect which can be combined with any one of the 36th to 39th aspects, the operating mode is negotiated based on an operating mode notification, a capability field, or a control response.

[0047] In the forty-first aspect which can be combined with any one of the thirty-sixth to fortieth aspects, the operation mode is set according to an indication in a Quality of Service Null (QoS-Null) frame.

[0048] In the 42nd aspect which can be combined with any one of the 36th to 41st aspects, the operating mode remains unchanged until a counter indication occurs in the QoS null frame.

[0049] In the forty-third aspect which may be combined with any one of the thirty-sixth to forty-second aspects, the operations of the method are performed by a non-access point station (non-AP STA).

[0050] In general, in a forty-fourth aspect, a method includes sending a non-high throughput physical protocol data unit (non-HT PPDU); and receiving a control frame in response to the non-HT PPDU, the control frame including an ultra-high reliability extended range single user PPDU (UHR ER SU PPDU) format.

[0051] In a forty-fifth aspect combinable with the forty-fourth aspect, the non-HT PPDU includes a request to send (RTS), and the control frame including the UHR ER SU PPDU format includes a clear to send (CTS).

[0052] In the forty-sixth aspect which can be combined with the forty-fourth aspect or the forty-fifth aspect, the control frame including the UHR ER SUPPDU format is received in a repetitive transmission mode over a bandwidth greater than or equal to 20 MHz.

[0053] In the 47th aspect which can be combined with any one of the 44th to 46th aspects, the control frame is received using the UHR ER SU PPDU format according to an operation mode.

[0054] In the 48th aspect which can be combined with any one of the 44th to 47th aspects, the operating mode is negotiated based on an operating mode notification, a capability field, or a control response.

[0055] In the 49th aspect which can be combined with any one of the 44th to 48th aspects, the operation mode is set according to an indication in a Quality of Service Null (QoS-Null) frame.

[0056] In the fiftieth aspect, which can be combined with any one of the forty-fourth to forty-ninth aspects, the operating mode remains unchanged until a counter indication occurs in the QoS empty frame.

[0057] In the fifty-first aspect which may be combined with any one of the forty-fourth to fiftieth aspects, the method is performed by an access point (AP).

[0058] In general, in aspect 52, a device comprises one or more processors and one or more storage devices storing instructions, which instructions can be executed by the one or more processors to cause the one or more processors to perform operations according to any of the preceding aspects.

[0059] Generally speaking, in the fifty-third aspect, a non-transitory computer storage medium stores instructions that can be executed by one or more processors to cause the one or more processors to perform operations according to any one of the first aspect to the fifty-first aspect.

[0060] Generally speaking, in the fifty-fourth aspect, at least one processor is configured to perform the operations according to any one of the first to fifty-first aspects.

[0061] Generally speaking, in aspect fifty-fifth, a system comprises one or more processors and one or more storage devices storing instructions, which instructions can be executed by the one or more processors to enable the one or more processors to perform operations according to any one of aspects one to fifty-first.

[0062] The details of one or more embodiments of these systems and methods are set forth in the following drawings and description. Other features, objects, and advantages of these systems and methods will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 A block diagram illustrating an example of an electronic device that conducts wireless communications according to some implementations is illustrated.

[0064] Figure 2A and Figure 2B Timing diagrams according to some specific implementations are illustrated.

[0065] Figure 3 Simulation results of packet detection according to some specific implementations are illustrated.

[0066] Figure 4 Simulation results of autocorrelation and cross-correlation based packet detection according to some specific implementations are illustrated.

[0067] FIG. 5A to FIG. 5H Simulation results for cross-correlation based packet detection according to some specific implementations are illustrated.

[0068] Figure 6 An example structure of an ultra high reliability extended range PPDU (UHR ER PPDU) according to some implementations is illustrated.

[0069] Figure 7 Example diagrams for generating a 1x format across an orthogonal frequency division multiplexing (OFDM) symbol according to some implementations are illustrated.

[0070] Figure 8 Simulation results for non-high-throughput PPDU and UHR ER PPDU according to some specific implementations are illustrated.

[0071] Fig.9A and Fig. 9B An example structure of a UHR ER PPDU including an extended range (ER) preamble according to some implementations is illustrated.

[0072] Fig. 10A and Fig. 10B An example structure of a UHR ER PPDU including a UHR preamble according to some implementations is illustrated.

[0073] Fig.11 An example structure of a UHR ERP PDU in which a legacy signal (L-SIG) field is omitted according to some implementations is illustrated.

[0074] Fig.12 An example structure of a UHRER PPDU in which a Repeat Legacy Signal (RL-SIG) field is omitted is illustrated according to some implementations.

[0075] Fig.13 An example structure of a UHR ERP PDU in which a Universal Signal (U-SIG) field is omitted according to some implementations is illustrated.

[0076] Fig.14A and Fig. 14B Examples of triggering procedures according to some specific implementations are illustrated.

[0077] Fig.15A and Fig. 15B Examples of enabling both enhanced distributed channel access (EDCA) and triggered-based uplink transmissions according to some implementations are illustrated.

[0078] Fig.16 Flowcharts illustrating example methods according to some implementations are shown.

[0079] Fig.17 Flowcharts illustrating example methods according to some implementations are shown.

[0080] Fig.18 Flowcharts illustrating example methods according to some implementations are shown.

[0081] Fig.19 Flowcharts illustrating example methods according to some implementations are shown.

[0082] Fig. 20 Flowcharts illustrating example methods according to some implementations are shown.

[0083] Fig.21 Flowcharts illustrating example methods according to some implementations are shown.

[0084] Fig. 22 A block diagram of an example electronic device is illustrated according to some implementations. DETAILED DESCRIPTION

[0085] In a Wi-Fi network, the transmit power of a non-access point station (non-AP STA) is about 10 decibels (dB) less than the transmit power of an access point station (AP STA). One reason for this difference is that government regulations impose different transmit power limits on APs and non-AP STAs. For example, the Federal Communications Commission (FCC) of the United States limits the transmit power of non-AP STAs operating in the 5.15 GHz to 5.25 GHz range to 24 dBm and 11 dBm per MHz, while allowing AP STAs operating in the same range to transmit at up to 30 dBm and 17 dBm per MHz. Another reason is the specific implementation differences between AP and non-AP STAs, such as AP STAs typically have better power amplifiers than non-AP STAs. Due to this transmit power difference, the transmission from a non-AP STA to an AP STA (also referred to herein as an "uplink transmission") may have a lower signal-to-noise ratio (SNR) relative to the transmission from an AP STA to a non-AP STA (also referred to herein as a "downlink transmission"). Therefore, the uplink link budget and reliability of uplink transmissions in a Wi-Fi network may be significantly lower than downlink transmissions, especially over extended range.

[0086] The present disclosure describes techniques for improving uplink link budget and reliability of uplink transmission in Wi-Fi and other wireless communication networks. According to one aspect of the present disclosure, an ultra-high reliability extended range physical layer protocol data unit (UHR ER PPDU) is described. In some examples, the UHR ER PPDU includes an ultra-high reliability extended range long training field (UHR-ER-LTF) and an ultra-high reliability extended range signal field (UHR-ER-SIG), which are modulated over the entire orthogonal frequency division multiplexing (OFDM) symbol length to improve the effective received power and SNR of the uplink transmission. In some examples, the described UHR ER PPDU includes an extended range preamble to enable the STA to decode the PPDU more efficiently. The present disclosure also provides techniques for center frequency offset (CFO) correction using cross-correlation to improve packet detection and overcome a 10dB transmit power difference. An improved trigger request process and an extension that can better control the control response frame format are also described. Note that while the present disclosure is described in the context of improving uplink communications, the techniques described herein may also be used to improve other communications, such as downlink communications or point-to-point communications where one device has lower capabilities or power than another device.

[0087] refer to Figure 1, a block diagram 100 of an example of an electronic device that performs wireless communication according to some specific implementations is shown. Notably, one or more electronic devices 110 (such as a smart phone, a laptop, a notebook computer, a tablet computer, or another such electronic device) and an access point 112 can wirelessly communicate in a WLAN using the IEEE 802.11 communication protocol. Thus, the electronic device 110 can be associated with the access point 112 or can have a connection with the access point. For example, the electronic device 110 and the access point 112 can perform wireless communication in the following situations: detect each other by scanning a wireless channel, send and receive beacons or beacon frames on the wireless channel, establish a connection (e.g., by sending a connection request), and / or send and receive packets or frames (packets or frames may include requests and / or additional information such as data as payload). It is noted that the access point 112 can provide access to a network such as the Internet via an Ethernet protocol and can be a physical access point or a virtual or "software" access point implemented on a computer or electronic device. In this specification, the electronic device 110 is sometimes referred to as a “receiving electronic device”, a “receiver station” or a “non-AP STA”, and the access point 112 is sometimes referred to as an “AP STA”.

[0088] Despite providing Figure 1 The environment shown is used as an example, but in alternative implementations, there may be different numbers and / or types of electronic devices. For example, some implementations may include more or fewer electronic devices. As another example, in some implementations, different electronic devices may send and / or receive packets or frames. In some implementations, multiple links may be used during communication between electronic devices 110.

[0089] As referenced below Fig.12 As further described, the electronic device 110 and the access point 112 may include subsystems such as a networking subsystem, a memory subsystem, and a processor subsystem. In addition, the electronic device 110 and the access point 112 may include a radio component 114 in the networking subsystem. More generally, the electronic device 110 and the access point 112 may include any electronic device with a networking subsystem (or may be included in any electronic device with a networking subsystem) that enables the electronic device 110 and the access point 112 to respectively communicate wirelessly with another electronic device. This may include sending beacons on a wireless channel to enable the electronic devices to make initial contact or detect each other, and then exchanging subsequent data / management frames (such as connection requests) to establish a connection, configure security options, send and receive packets or frames via the connection, etc.

[0090] like Figure 1As shown, wireless signals 116 are communicated by one or more radio components 114-1 and 114-2 in the electronic device 110-1 and the access point 112, respectively. For example, as previously mentioned, the electronic device 110-1 and the access point 112 may exchange packets or frames using the Wi-Fi communication protocol in the WLAN. In addition, the one or more radio components 114-1 may receive the wireless signals 116 transmitted by the one or more radio components 114-2 via one or more links between the electronic device 110-1 and the access point 112. Alternatively, the one or more radio components 114-1 may transmit the wireless signals 116 received by the one or more radio components 114-2.

[0091] In some implementations, the wireless signals 116 are communicated by one or more radio components 114 in the electronic device 110 and the access point 112, respectively. For example, the one or more radio components 114-1 and 114-3 can receive the wireless signals 116 sent by the one or more radio components 114-2 via one or more links between the electronic devices 110-1 and 110-2 and the access point 112.

[0092] In some implementations, the access point 112 may group the electronic devices 110 into a target site set. The concept of a target site set comes from downlink multi-user transmission, where the access point 112 may use orthogonal frequency division multiple access (OFDMA) or multi-user (MU) multiple input multiple output (MU-MIMO) to transmit to multiple sites simultaneously in one PPDU. Here, the target site set is a set of sites that can be served by the access point 112 at the same time. The sites in the set do not need to share the same PHY parameters, such as MCS, number of streams, etc.

[0093] In some implementations, the access point 112 may use multi-user (MU) technology (such as MU multiple-input multiple-output (MU-MIMO)) to communicate with multiple electronic devices 110 simultaneously. In some examples, the access point 112 communicates with the electronic devices 110 using frequency reuse, so that the access point 112 allocates a portion of the total bandwidth to each of these electronic devices. For example, in order to communicate with four electronic devices simultaneously on an 80 megahertz (MHz) bandwidth, the access point 112 sends a MU-PPDU on the 80 MHz bandwidth. The MU-PPDU includes a sub-PPDU for each of the four electronic devices, where each sub-PPDU (or sub-channel) is allocated 20 MHz. The access point 112 may use the MU-PPDU to communicate with devices in the same target set, devices in different target sets, or a combination of both.

[0094] In some specific implementations, the access point 112 and one or more electronic devices may be compatible with the IEEE 802.11 standard (e.g., IEEE 802.11ax) including trigger-based channel access. In 802.11ax, orthogonal frequency division multiple access (OFDMA) is used to enable simultaneous communication between the access point 112 and multiple electronic devices. OFDMA divides the available physical spectrum into multiple orthogonal subchannels or resource units (RUs) that can be allocated to different electronic devices (users). According to the standard, the access point 112 coordinates multi-user OFDMA by broadcasting a trigger frame, which also allocates RUs to each participating electronic device. Each electronic device responds to the trigger frame by sending a PPDU to the access point 112 using the allocated RU. The trigger frame may also include power control information. The access point 112 may indicate when all electronic devices 110 start and stop transmitting. It should be noted that the access point 112 and the electronic device 110 may communicate with one or more traditional electronic devices that are not compatible with the IEEE 802.11 standard (i.e., do not use multi-user triggered channel access).

[0095] In some embodiments, processing a packet or frame in one of the electronic devices 110, the access point 112, or a combination of both includes: receiving a wireless signal 116 that encodes the packet or frame; decoding / extracting the packet or frame from the received wireless signal 116 to obtain the packet or frame; and processing the packet or frame to determine information contained in the packet or frame (such as data in a payload).

[0096] As discussed above, due to, for example, government regulations and specific implementation differences, the transmit power of a non-AP STA is approximately 10 dB less than the transmit power of an AP STA. This 10 dB transmit power difference can also be considered as a 7 dB link budget difference because an AP STA typically has more antennas than a non-AP STA (e.g., an AP STA has four antennas, while a non-AP STA has two antennas). Therefore, in order to improve the reliability of transmission in the uplink direction (e.g., from a non-AP STA to an AP STA or another non-AP STA), it is necessary to improve the transmit power of the non-AP STA by, for example, 10 dB or otherwise reduce the 7 dB link budget difference. In other words, a PPDU design is needed whose SNR in the uplink direction is, for example, 10 dB lower than in the downlink direction (e.g., from an AP STA to a non-AP STA).

[0097] In general, when receiving a PPDU, a Wi-Fi receiver performs packet detection (e.g., mainly based on the legacy short training field (L-STF)), center frequency offset (CFO) estimation and correction (e.g., coarse tuning using L-STF and fine tuning using the legacy long training field (L-LTF)), channel estimation, demodulation, and decoding. Therefore, in low SNR areas (e.g., uplink), using a longer sequence than L-STF can help improve packet detection and coarse CFO correction.

[0098] However, if Figure 2A As shown, each STA needs to check whether the channel is idle during aSlotTime (by performing idle channel assessment in aCCATime), which is 9μs for a 20MHz interval. Taking this into account, packet detection should be completed within L-STF, which is less than 8μs, as shown in Figure 2B Therefore, it is not possible to use sequences longer than L-STF within the Wi-Fi framework, as doing so would disrupt the legacy CCA process by forcing the receiver to wait longer than the slot time to determine whether it has received a new PPDU.

[0099] According to one aspect of the present disclosure, it is considered whether there is a better sequence than L-STF that can be used, or whether L-STF can be used under different assumptions. For the purpose of discussion and not limitation, it can be assumed that a non-AP STA has two antennas and an AP STA has four antennas.

[0100] Generally speaking, the MCS0 (beacon) sensitivity of a non-AP STA is at least 3dB worse than the Pmiss (packet detection) of a non-high throughput (non-HT) PPDU. Figure 3 As shown and summarized in the following table. Therefore, in order to overcome the above 10 dB transmit power difference, the packet detection performance should be improved by at least 6.7 dB (eg, 10 dB to 3.3 dB).

[0101] Required SNR data 3.5dB PD 0.2dB Difference 3.3dB

[0102] Typically, WLAN receivers use autocorrelation for packet detection due to CFO. However, autocorrelation is limited in ultra-low SNR regions. Therefore, according to one aspect of the present disclosure, cross-correlation is used to improve packet detection. In order to use a cross-correlation-based algorithm, the amount of phase difference within the sequence used for correlation should be small. If the STA can correct the CFO before sending, the receiver does not need to correct the CFO before processing other fields. For a triggered (TB) PPDU, the requirement for the 10% point of the complementary cumulative distribution function (CCDF) of the CFO error in the additive Gaussian-Gaussian white noise (AWGN) at a received signal strength indicator (RSSI) of -60dBm in 20MHz is 350Hz for a high-efficiency (HE) TB PPDU and 2kHz for a non-HT PPDU or non-HT repeated transmission. In some examples, the CFO requirement for transmissions other than the TB PPDU is + / -20ppm. If it is assumed that the beacon requires 3dB SNR on the downlink, a residual CFO of 15kHz can be achieved at 1%, or a residual CFO of 8.4kHz can be achieved at 10%. Therefore, according to one aspect of the present disclosure, it is proposed to impose strict CFO requirements (e.g., a residual CFO error less than or equal to 15kHz) before sending the extended range PPDU described herein.

[0103] By reducing the CFO, longer sequences can be used for cross-correlation, thereby improving packet detection. For example, the amount of difference in the cross-correlation due to CFO is N 2 -|∑ k e j2πkct |s k | 2 | 2 , where N is the number of samples in the sequence, c is the residual CFO value, and t is time. Therefore, a residual CFO of 15kHz results in a change of 0.036 radians in 2.4μs, which is (0.9745+0.2243j)*signal. For the 15kHz residual CFO case, the value difference is 0.07dB. Note that for the 150kHz residual CFO case, the value difference is 2dB. Therefore, as long as the residual CFO value is not too large, the packet detection threshold still works. Figure 4 As shown, the L-STF power is increased by 3dB, cross-correlated and without CFO correction, and the residual CFO is 15kHz, which can achieve 8.5dB gain. Note that Figure 4 The autocorrelation based method shown uses a 0.8 μs correlation factor.

[0104] In some examples, cross-correlation based packet detection may be performed as follows. First, the sum of three correlation factors is determined. For example, the cross-correlation of a reference STF (e.g., length 48 or 2.4 μs) and three input signals (e.g., current, 48 delayed, 96 delayed) normalized by the signal strength of the input sequence may be determined, such as Figure 5A and Figure 5B Alternatively, a correlation factor can be used and the value saved, such as Figure 5C and Figure 5D In some examples, a flag may be set after detecting a first correlation factor above a certain value, which may then be confirmed after checking the delayed version. From here, the sum of the above 0.8 μs values ​​is determined to capture the energy in the different channel taps. This is for example Figure 5E and Fig. 5F (three related factors) and Figure 5G and Figure 5H (a correlation factor). Finally, whether a packet is detected is determined by checking whether the sum value exceeds the threshold value X times within 3.2 μs (64 samples) after the sum value exceeds the threshold value Y. For example, X may be 45 and Y may be 0.5.

[0105] According to one aspect of the present disclosure, an ultra high reliability extended range PPDU (UHR ER PPDU) format is disclosed. For example, such a format can improve SIG decoding performance and SNR, as described below. Figure 6 , shows an example UHR ER PPDU format. In this example, the UHR ER PPDU includes L-STF, L-LTF, TBD, UHR-ER-LTF, UHR-R-SIG, data, and PE fields. In some examples, the L-STF and L-LTF are power-boosted by 3dB. The fields between the L-LTF and the UHR-ER-LTF (in Figure 6 In some examples, the PE field may be omitted.

[0106] In order to improve the received power, the UHR-ER-LTF and / or UHR-ER-SIG fields may use the 1x format, but over the entire OFDM symbol length. Here, the 1x format refers to the duration of the symbol (e.g., OFDM symbol) containing the UHR-ER-LTF or UHR-ER-SIG. In some examples, the 1x format corresponds to a symbol duration of 3.2μs (obtained by 1 / 4 compression of a 12.8μs OFDM symbol), while the 2x format corresponds to a symbol duration of 6.4μs (obtained by 1 / 2 compression), and the 4x format corresponds to a symbol duration of 12.8μs (uncompressed). According to one aspect of the present disclosure, in order to increase the received power, the 1x format UHR-ER-LTF and / or UHR-ER-SIG (nominal 3.2μs) is modulated over the entire OFDM length (e.g., 12.8μs), such as by using every four subcarriers. Figure 7 An example diagram for generating such signals (eg, UHR-ER-LTF and / or UHR-ER-SIG) is shown in FIG.

[0107] In some examples, the UHR-ER-LTF and / or UHR-ER-SIG fields are repeated four times in the time domain, which will result in a 6dB power boost effect. These fields can use the same FFT size as the HE / EHT / UHR data field (e.g., 256 for 20MHz and 512 for 40MHz). The OFDM symbol length (e.g., duration) is 12.8μs plus a guard interval (e.g., 3.2μs), resulting in a total OFDM symbol length of 16μs. In some examples, there are non-zero values ​​in every four subcarriers. For bandwidths wider than 20MHz, all unpunctured 20MHz can be identical.

[0108] In some examples, for the UHR-ER-LTF and / or UHR-ER-SIG fields, 52 frequency-tuned resource units (RUs) in 20 MHz with 4x subcarrier positions of the non-HT PPDU are used. For the UHR-ER-LTF, the modulation may be the same or similar to the L-LTF in the non-HT DUP PPDU, except that the modulated subcarrier index is every 4th frequency tone. For the UHR-ER-SIG, the modulation and decoding (e.g., BPSK, BCC R=1 / 2) may be the same or similar to the L-SIG in the non-HT DUP PPDU, except that the modulated subcarrier index is every 4th frequency tone. In 20 MHz, the subcarrier indices [-26, -25, ..., 25, 26] may become [-104, -100, ..., 100, 104], respectively. In some examples, the pilot may be boosted by 3 dB.

[0109] In some examples, the HE / EHT / U-SIG frequency modulation plan is used for the UHR-ER-LTF and / or UHR-ER-SIG fields. For the UHR-ER-LTF, the modulation is the same or similar to the L-LTF in the HE / EHT PPDU, except that the modulated subcarrier index is every 4 frequency tones. For the UHR-ER-SIG, the modulation and decoding (e.g., BPSK, BCC R=1 / 2) are the same or similar to the modulation and decoding of the U-SIG, except that the modulated subcarrier index is every 4 frequency tones and on one symbol. In 20MHz, the subcarrier indices [-28, -27, ..., 27, 28] may become [-112, -108, ..., 108, 112] respectively. In some examples, the data field may use the same structure as the UHR-ER-LTF and / or UHR-ER-SIG fields.

[0110] As discussed above, to improve packet detection performance, power boosting of L-STF and L-LTF with CFO correction (e.g., boosting by 3 dB) may be used. In some examples, the L-STF and / or L-LTF fields of a PPDU (e.g., UHR ER PPDU) may be power boosted by more than 3 dB (e.g., 5 dB) to improve packet detection performance without CFO correction (although in some examples, CFO correction may be used with L-STF / L-LTF boosted by more than 3 dB). In general, power boosting fields (e.g., L-STF and L-LTF and other fields) refers to increasing the transmit power of these fields. The maximum power boost that may be applied in a specific implementation may vary due to transmit requirements (such as maximum transmit power level and transmit spectrum mask). If a 5 dB power boost can be applied to L-STF and L-LTF in a specific implementation, such a 5 dB boost may be applied to improve packet detection performance without CFO correction. On the other hand, if a power boost of, for example, 5 dB is not possible in a particular implementation, CFO correction may be performed with a lower (eg, 3 dB) power boost on L-STF and L-LTF to achieve the desired packet detection performance.

[0111] refer to Figure 8, simulation results for non-HT PPDU and the proposed UHR ER PPDU are shown. For non-HT PPDU, 4 transmitters (Tx) with cyclic delay diversity (CDD) and 2 receivers (Rx) with 200B (byte) data length and binary convolutional code (BCC) are used. For UHR ER PPDU, 2Tx (CDD) and 4Rx with 200B BCC are used. In this example, the residual CFO is 15kHz, the L-STF and L-LTF in the UHR ER PPDU are power-boosted by 3dB, and the UHR-ER-SIG and UHR-ER-DATA follow the traditional frequency modulation plan with 4x subcarrier positions (e.g., 1x format with a full 4x OFDM symbol duration). Since UHR-ER-LTF, UHR-ER-SIG, and UHR-ER-DATA are repeated 4 times in the time domain, they can be used for CFO correction. In this example, the CFO is estimated during the UHR-ER-LTF period, and the residual phase offset is compensated by the pilot. In addition, the data rate in this example is 1.5 Mbps (e.g., 6 Mbps / 4). Figure 8 As shown, the UHR ERP PDU described herein performs 10 dB better than the non-HT PPDU, thereby improving the uplink SNR and offsetting the link budget difference.

[0112] Generally speaking, in some cases, it may be beneficial to have a shorter UHR ERPPDU format, for example, to reduce latency and the chance of collision. For example, to help solve the hidden node problem, some networks (e.g., Wi-Fi networks) may use a transmit request and transmit clear (RTS / CTS) process. During this process, a transmitter (e.g., a non-AP STA) transmits an RTS to a receiver (e.g., an AP). In response, the receiver transmits a CTS to the transmitter, and the transmitter may then transmit a PPDU. In this case, the receiver (and other STAs within range) should not transmit before the end of the PPDU to avoid collisions, although collisions may still occur in some cases (such as when there are exposed nodes). Therefore, considering the potential trade-offs in compatibility and functionality, adopting a shorter PPDU format may be beneficial to reduce latency and further reduce the chance of collisions.

[0113] refer to Fig.9A and Fig. 9BAccording to one aspect of the present disclosure, an example format of a UHR ER PPDU is proposed. Generally speaking, it is expected that the receiver does not need the fields between the L-LTF and the UHR-ER-LTF. Therefore, it is proposed to use an ER preamble structure so that more STAs can decode the preamble and postpone it to the end of the PPDU. Such an ER preamble may include an L-SIG field, an RL-SIG field, a U-SIG field, and a UHR-STF field, such as Fig.9A In some examples, the UHR-STF field may be omitted, such as Fig. 9B In some examples, the PE field may be omitted.

[0114] Fig. 10A and Fig. 10B An additional example format of a UHR ER PPDU according to an aspect of the present disclosure is shown. As mentioned above, it is contemplated that the receiver does not require the fields between the L-LTF and the UHR-ER-LTF. Furthermore, in some examples, the ER preamble may be too long. Therefore, it is proposed to use a UHR PPDU preamble structure such as Fig. 10A In some examples, the UHR-STF field may be omitted, such as Fig. 10B In some examples, the PE field may be omitted.

[0115] Note that not all STAs in the basic service set may be able to decode this packet, which may be addressed by using the UHR ER PPDU to carry the RTS (or its variants) and the AP to carry the CTS (using non-HT / non-HT DUP).

[0116] Fig.11 , Fig.12 and Fig.13 A further example of a UHR ER PPDU format according to aspects of the present disclosure is illustrated. Fig.11, example UHR ER PPDU formats 1100a-1100i are shown, in which the L-SIG field (and RL-SIG field) are omitted. For example, such formats may be useful in situations where an unexpected STA does not need to detect the ER PPDU. In some examples, the UHR-STF field may be omitted in addition to the L-SIG field (and other fields), such as shown in formats 1100d-1100i. For example, such formats may be useful when beamforming is not applied. In some examples, the UHR-ER-LTF field may be omitted in addition to the L-SIG field (and other fields), such as shown in formats 1100g-1100i. For example, such formats may be useful when channel estimates from the L-LTF may be used for the UHR-ER-SIG and / or data fields. In some examples, such as when there is no data to be transmitted, the data field may be omitted in addition to the L-SIG field (and other fields), such as shown in formats 1100c, 1100f, and 1100i. In some examples, the PE field may be omitted in addition to the L-SIG field (and other fields), such as shown in formats 1100b-1100c, 1100e-1100f, and 1100h-1100i.

[0117] refer to Fig.12 , example UHR ER PPDU formats 1200a-1200i are shown, in which the RL-SIG field is omitted. For example, such formats may be useful in the case where an unexpected STA or a legacy STA treats the ER PPDU as a non-HT PPDU. In some examples, the UHR-STF field may be omitted in addition to the RL-SIG field (and other fields), such as shown in formats 1200d-1200i. For example, such formats may be useful when beamforming is not applied. In some examples, the UHR-ER-LTF field may be omitted in addition to the RL-SIG field (and other fields), such as shown in formats 1200g-1200i. For example, such formats may be useful when channel estimates from the L-LTF may be used for the UHR-ER-SIG and / or data fields. In some examples, such as when there is no data to be transmitted, the data field may be omitted in addition to the RL-SIG field (and other fields), such as shown in formats 1200c, 1200f, and 1200i. In some examples, the PE field may be omitted in addition to the RL-SIG field (and other fields), such as shown in formats 1200b-1200c, 1200e-1200f, and 1200h-1200i.

[0118] refer to Fig.13, example UHR ER PPDU formats 1300a-1300i are shown, in which the U-SIG field is omitted. For example, such formats may be useful in the case where a legacy STA treats the ER PPDU as a non-HT PPDU. In some examples, the UHR-STF field may be omitted in addition to the U-SIG field (and other fields), such as shown in formats 1300d-1300i. For example, such formats may be useful when beamforming is not applied. In some examples, the UHR-ER-LTF field may be omitted in addition to the U-SIG field (and other fields), such as shown in formats 1300g-1300i. For example, such formats may be useful when channel estimates from the L-LTF may be used for the UHR-ER-SIG and / or data fields. In some examples, such as when there is no data to be transmitted, the data field may be omitted in addition to the U-SIG field (and other fields), such as shown in formats 1300c, 1300f, and 1300i. In some examples, the PE field may be omitted in addition to the U-SIG field (and other fields), such as shown in formats 1300b-1300c, 1300e-1300f, and 1300h-1300i.

[0119] In some examples, according to one aspect of the present disclosure, the meaning of one or more fields or parameters of the SIG field in the UHR ER PPDU may be modified. For example, in some examples, the length field or parameter in the L-SIG field (or RL-SIG field) may be used to indicate the end of a transmit opportunity (TXOP) and / or the TXOP duration, rather than the PPDU end and / or the PPDU duration. In some examples, the PPDU type and compression mode fields in the U-SIG field may be used to notify that the PPDU is a UHRER PPDU. In this way, if the STA is expected to be able to decode the U-SIG field, the PPDU type and compression mode will confirm that it is a UHR ER PPDU format.

[0120] In some examples, according to one aspect of the present disclosure, the UHR-ER-SIG field may include one or more of the following fields or parameters to facilitate decoding of the ER PPDU. In some examples, the UHR-ER-SIG may include a length field, such as an L-SIG length field or a similar length field (e.g., the number of OFDM symbols), so that the intended STA knows the length of the PPDU. In some examples, the UHR-ER-SIG may indicate the modulation coding scheme (MCS) level of the data field (e.g., MSC0, MSC1, etc.). If only one MSC level is used, this parameter may be omitted. In some examples, the UHR-ER-SIG may include an indication of the coding (e.g., binary convolutional code (BCC) or low-density parity check code (LDPC)). If only one type of code is used (e.g., one of BCC or LDPC), this parameter may be omitted. In some examples, the UHR-ER-SIG may include LDPC additional symbol segments, pre-FEC filling factor, and / or PE disambiguation fields or parameters. If these values ​​are fixed, these fields or parameters may be omitted, as described below. In some examples, the UHR-ER-SIG may include a BSS color field or parameter. In some examples, the UHR-ER-SIG may include a STA-ID. In some examples, the UHR-ER-SIG may include a CRC or parity bit. In some examples, for the ER PPDU, the pre-FEC padding factor and / or the LDPC extra symbol segment may be fixed. For example, for better decoding performance, the LDPC extra symbol may be set to 1 and the pre-FEC padding factor may be set to 3. In some examples, padding (e.g., a zero-length MPDU at the MAC layer) may be used to satisfy these fixed values.

[0121] In some examples, a low imposed error rate may make the ER PPDU longer than a traditional PPDU. To avoid this, according to one aspect of the present disclosure, a maximum size or length may be imposed on the ER PPDU. For example, such a limit may be imposed on an ER PPDU using enhanced distributed channel access (EDCA). In some examples, the number or other length of OFDM symbols specified in the ER-SIG field may limit the maximum ER-PPDU size. In some examples, the AP sets an ER-PPDU length limit for EDCA. For example, if the AP sets ERPPDULengthThreshold, a non-AP STA shall not use EDCA to transmit an ER-PPDU whose PPDU length is longer than ERPPDULengthThreshold. In some examples, this limit may be imposed only on data frames, while no limit (or different limits) may be imposed on control, action and / or management frames. When there is an unassociated STA, there is no STA-ID. In this case, until the AP obtains the STA-ID (e.g., after the association response frame is successfully delivered to the STA), the unassociated STA can then use the ER PPDU (e.g., for a probe request frame, an association request frame, etc.) without a maximum size limitation.

[0122] According to one aspect of the present disclosure, an improved triggering process is disclosed. Generally speaking, a non-AP STA may send a trigger request to an AP to request the AP to trigger the non-AP STA to send data. For example, if a packet in a queue of the non-AP STA is large enough that the non-AP STA cannot send the packet using an ER-PPDU whose length is less than a threshold (e.g., the maximum size threshold discussed above), the non-AP STA may send a trigger request 1400 to the AP, such as Fig.14A As shown. In some examples, the trigger request frame 1400 includes non-AP STA information (such as an address (e.g., a MAC address or a STA-ID)), packet information (such as a first packet (e.g., MPDU) size, a queue size, access category information, and / or a packet type (e.g., control, management, data frame), etc.). The trigger request frame 1400 may also include AP information, such as an address (e.g., a MAC address or a BSS color). Once the AP receives the request of the trigger frame 1400, the AP may trigger 1402 the non-AP STA to send in a subsequent TB-PPDU 1404, and grant a minimum duration of the TB-PPDU 1404 based on the information included in the request of the trigger frame 1400 (e.g., a first packet size, a queue size).

[0123] refer to Fig. 14BIn some examples, after receiving the trigger request 1410, the AP may first transmit an acknowledgment 1412 before triggering the non-AP STA to transmit (1414) in a subsequent TB-PPDU 1416. In doing so, the AP is given more time to determine a sufficient minimum duration (and allocate resources for) the TB-PPDU 1416 based on the size information included in the trigger request frame 1410.

[0124] In some examples, according to one aspect of the present disclosure, both EDCA and triggered uplink transmissions may be enabled. Fig.15A , in a first mode (e.g., Mode 1) in which the AP is serving a single non-AP STA, the AP receives a trigger request 1500 from the non-AP STA and, in response, sends an acknowledgment 1502 with an indication that the non-AP STA should transmit without waiting for a trigger. In some examples, such an indication may be a mode indication (e.g., Mode 1). Based on the indication in the acknowledgment 1502, the non-AP STA knows to send a UHR ER PPDU 1504 without waiting for a trigger. In this case, a network allocation vector (NAV) protection may be used to indicate the duration of the UHR ER PPDU to other STAs (and to prevent collisions with other STAs that may be listening). Reference Fig. 15B , in a second mode (e.g., Mode 2) in which the AP is serving multiple non-AP STAs with trigger frames, the AP receives a trigger request 1510 from the non-AP STA and, in response, sends an acknowledgment 1512 with an indication that the non-AP STA should wait for a trigger message before sending. In some examples, such an indication may be a mode indication (e.g., Mode 2). Based on the indication in the acknowledgment 1512, the non-AP STA waits for a trigger 1514 from the AP before sending in a UHR-TB-PPDU 1516.

[0125] According to the IEEE 802.11ax ER SU PPDU rules, a control frame transmitted by a HE STA as a response to a HE SU PPDU or a non-HT PPDU that does not contain a trigger frame shall be carried in a non-HT PPDU, unless the most recent PPDU transmitted by the HE STA to the recipient of the control frame after association is a HE ER SU PPDU. In this case, the control frame shall be carried in the HEER SU PPDU. Similarly, a control frame transmitted by a HE STA as a response to a HE ER SU PPDU that does not contain a trigger frame shall be carried in a HE ER SU PPDU, unless the most recent PPDU transmitted by the HE STA to the recipient of the control frame after association is a HE ER SU PPDU. In this case, the control frame shall be carried in a non-HT PPDU. In addition, if the channel bandwidth of the PPDU containing the frame that triggered the response is greater than 20 MHz, the control response frame shall not be transmitted in the HE ER SU PPDU.

[0126] In view of the above rules, the format of the control response frame to the HE ER SU PPDU is restricted to any previous transmission of the HE ER SU PPDU. That is, if the responder STA has not transmitted any HE ER SU PPDU in the uplink before transmitting the control response, the responder STA cannot transmit the control response in the HE ER SU PPDU. On the other hand, if the format of the previous PPDU transmitted by the responder is not the HE ER SU PPDU, the format of the control response frame of the HE ER SU PPDU should be non-HT PPDU.

[0127] According to one aspect of the present disclosure, the rules of the HE ER SU PPDU control response frame are extended to allow a control response having a UHR ER SU PPDU format to be transmitted in response to a non-HT PPDU, a HE / EHT / UHR SU PPDU and / or a HE ER SU PPDU. Specifically, it is proposed to allow the transmission of a UHR ER SU PPDU in a repeated transmission mode in response to a non-HT PPDU, a HE / EHT / UHR SU PPDU and / or a HE ER SU PPDU when the bandwidth is greater than 20 MHz. In this way, a CTS may be transmitted using the UHR ER PPDU format in response to an RTS transmitted using a non-HT PPDU format (as well as other examples). For an unassociated STA, if the STA transmits a probe request or an association request using a UHR ER PPDU, the AP should expect a UHR ER PPDU format for a control response, for example, a control response frame for a probe response and an association response.

[0128] In some examples, the aforementioned capabilities may be included in an operational mode that can be enabled (and disabled) by negotiation between the AP and the STA. Such negotiation may be implemented, for example, using an operational mode notification (OMN) frame, through a capability field or other capability messaging, and / or through a control response, etc. If this mode is enabled, the STA may send a control response using a UHR-ER-SU-PPDU, regardless of the received PPDU format or a newer PPDU transmitted by the STA to the recipient of the control frame. In this example, the AP expects to receive a UHR-ER-SU-PPDU and sets the TXOP duration accordingly when it initiates a TXOP.

[0129] In some examples, a semi-static operating mode change may be used. For example, an indication in the QoS-NULL (or another frame) may be used to inform the AP that the UHR-ER-SU-PPDU format will be used as a control response. In some examples, a single bit is used to enable / disable the mode. For example, a 1 (or 0) may be used to enable the mode (e.g., the control response is a UHR-ER-SU-PPDU format), and a 0 (or 1) may be used to disable the mode (e.g., the control response is a non-HT PPDU format).

[0130] In some examples, a dynamic operation mode change may be used. For example, when the AP receives a first response as a UHR ER PPDU, the AP may assume that the remainder of the response will be in a UHR ER PPDU until the STA disables it using the semi-static operation mode change described above. When the AP receives an unsolicited PPDU in UHR ER format, the AP will assume that the remainder of the response will be in UHR ER format until the STA disables it using, for example, the semi-static operation mode change discussed above.

[0131] Fig.16 A flowchart of an example method 1600 according to some specific implementations is illustrated. For clarity of presentation, the following description generally describes the method 1600 in the context of other figures in this specification. For example, the method 1600 may be performed by Figure 1 The method 1600 may be performed by one or more electronic devices in the electronic device 110. It should be understood that the method 1600 may be performed by any suitable system, environment, software, hardware, or a combination of systems, environments, software, and hardware, as appropriate. In some specific implementations, the steps of the method 1600 may be executed in parallel, in combination, in a loop, or in any order.

[0132] The operations of the method 1600 include generating 1602 an extended range physical layer protocol data unit (ER-PPDU) for transmission to a receiver. The PPDU includes an ultra high reliability extended range long training field (UHR-ER LTF) and an ultra high reliability extended range signal field (UHR-ER SIG). After generating the ER-PPDU, the method 1600 includes transmitting 1604 the PPDU to the receiver, wherein at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated two or more times in the time domain or the frequency domain.

[0133] Fig.16 The example method 1600 shown may be modified or reconfigured to include additional, fewer, or different steps ( Fig.16 (not shown), these steps may be performed in the order shown or in a different order. In some examples, at least one of the UHR-ER-LTF or the UHR-ER-SIG uses a 1x format. In some examples, at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of the OFDM symbol using every four subcarriers of the OFDM symbol. In some examples, the ER-PPDU includes 52 frequency-tuned resource units and a channel bandwidth of 20 MHz, and at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of the OFDM symbol using every four subcarriers from subcarrier index -104 to subcarrier index 104 (or from subcarrier index -112 to 112 when the HE / EHT / U-SIG frequency-tuning plan is used). In some examples, at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated four times in the ER-PPDU in the time domain or the frequency domain. In some examples, the OFDM symbol length including the guard interval is 16 microseconds.

[0134] In some examples, the ER-PPDU includes an extended range preamble that includes a legacy short training field (L-STF), a legacy long training field (L-LTF), and one or more additional fields between the L-LTF and the UHR-ER-LTF, such as one or more of a legacy signal field (L-SIG), a repeated legacy signal field (RL-SIG), or a universal signal field (U-SIG). At least one of the L-STF and the L-LTF may be power-boosted by 3 dB or more (e.g., between 3 dB and 6 dB). In some examples, the PPDU also includes an ultra-high reliability short training field (UHR-STF).

[0135] In some examples, method 1600 includes obtaining data to send to a receiver, and the PPDU includes a data field that includes at least a portion of the data to send to the receiver. In some examples, the data field is repeated two or more times in the time domain or the frequency domain. In some examples, the data field is modulated over the entire OFDM symbol length using every four subcarriers of the OFDM symbol, and the data field is repeated four times in the ER-PPDU. In some examples, method 1600 includes performing a center frequency offset (CFO) correction before sending the PPDU to the receiver, wherein the residual CFO after performing the CFO correction is less than or equal to 15 kHz.

[0136] Fig.17 A flowchart of an example method 1700 according to some specific implementations is illustrated. For clarity of presentation, the following description generally describes the method 1700 in the context of other figures in this specification. For example, the method 1700 may be performed by Figure 1 The access point 112 of the embodiment of the present invention is executed. It should be understood that the method 1700 can be executed by any suitable system, environment, software, hardware or a combination of systems, environments, software and hardware as appropriate. In some specific implementations, the steps of the method 1700 can be executed in parallel, in combination, in a loop or in any order.

[0137] The operations of the method 1700 include receiving 1702 an extended range physical layer protocol data unit (ER-PPDU), the ER-PPDU including an ultra high reliability extended range long training field (UHR-ER LTF) and an ultra high reliability extended range signal field (UHR-ER SIG), wherein at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated two or more times in the time domain or the frequency domain. Upon receiving the ER-PPDU, the method 1700 includes processing 1704 the PPDU to obtain information included in at least one of the UHR-ER-LTF or the UHR-ER-SIG.

[0138] Fig.17 The example method 1700 shown may be modified or reconfigured to include additional, fewer, or different steps ( Fig.17(not shown), these steps may be performed in the order shown or in a different order. In some examples, at least one of the UHR-ER-LTF or the UHR-ER-SIG uses a 1x format. In some examples, at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of the OFDM symbol using every four subcarriers of the OFDM symbol. In some examples, the ER-PPDU includes 52 frequency-tuned resource units and a channel bandwidth of 20 MHz, and at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of the OFDM symbol using every four subcarriers from subcarrier index -104 to subcarrier index 104 (or from subcarrier index -112 to 112 when the HE / EHT / U-SIG frequency-tuning plan is used). In some examples, at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated four times in the ER-PPDU.

[0139] In some examples, the ER-PPDU includes a data field modulated over the entire length of an OFDM symbol using every four subcarriers of the OFDM symbol and repeated four times in the PPDU, and the method 1700 includes processing the ER-PPDU to obtain data from the transmitter. In some examples, the ER-PPDU includes an extended range preamble, the extended range preamble including a legacy short training field (L-STF), a legacy long training field (L-LTF), and one or more additional fields between the L-LTF and the UHR-ER-LTF, such as one or more of a legacy signal field (L-SIG), a repeated legacy signal field (RL-SIG), or a universal signal field (U-SIG), and the method 1700 includes processing the ER-PPDU to obtain information included in at least one of the L-STS, L-LTF, L-SIG, RL-SIG, or U-SIG. The L-STF and the L-LTF may be power boosted by 3 decibels or more. In some examples, the ER-PPDU includes an ultra high reliability short training field (UHR-STF), and method 1700 includes processing the PPDU to obtain information included in the UHR-STF.

[0140] In some examples, method 1700 includes performing cross-correlation to detect a center frequency offset (CFO) of the ER-PPDU. In some examples, the CFO of the ER-PPDU is corrected prior to transmission such that a residual CFO of the ER-PPDU is less than or equal to 15 kHz.

[0141] Fig.18 A flowchart of an example method 1800 according to some specific implementations is illustrated. For clarity of presentation, the following description generally describes the method 1800 in the context of other figures in this specification. For example, the method 1800 may be performed by Figure 1 The method 1800 may be performed by one or more electronic devices in the electronic device 110. It should be understood that the method 1800 may be performed by any suitable system, environment, software, hardware, or a combination of systems, environments, software, and hardware, as appropriate. In some specific implementations, the various steps of the method 1800 may be executed in parallel, in combination, in a loop, or in any order.

[0142] The operation of method 1800 includes sending a trigger request to a receiver (1802). The trigger request indicates a size of data to be sent to the receiver (e.g., a first packet size). In some examples, the trigger request indicates other information, such as address information of the transmitter and / or receiver (e.g., MAC address, STA-ID BSS color), queue size, access category information, and / or packet type (e.g., control, management, data frame), etc. In some examples, the trigger request is sent in response to the size of the data satisfying a threshold (e.g., a maximum size value that may be indicated by the receiver).

[0143] In response to the trigger request, a trigger is received 1804 from the receiver. The trigger indicates a duration for sending data to the receiver, the duration being determined based on the size of the data indicated in the trigger request. In some examples, a confirmation of the trigger request is received from the receiver before the trigger is received.

[0144] Based in part on the duration, a trigger-based physical layer protocol data unit (TB-PPDU) is generated 1806. The TB-PPDU includes data to be sent to the receiver. In some examples, the TB-PPDU is an ultra-high reliability TB-PPDU. After the TB-PPDU is generated, the TB-PPDU can be sent to the receiver.

[0145] Fig.19 A flowchart of an example method 1900 according to some specific implementations is illustrated. For clarity of presentation, the following description generally describes the method 1900 in the context of other figures in this specification. For example, the method 1900 may be performed by Figure 1 The method 1900 may be performed by one or more access points 112 of the system. It should be understood that the method 1900 may be performed by any suitable system, environment, software, hardware, or a combination of systems, environments, software, and hardware, as appropriate. In some specific implementations, the steps of the method 1900 may be executed in parallel, in combination, in a loop, or in any order.

[0146] The operation of method 1900 includes receiving a trigger request from a transmitter (1902). The trigger request indicates the size of data to be sent by the transmitter (e.g., a first packet size). In some examples, the trigger request indicates other information, such as address information of the transmitter and / or receiver (e.g., MAC address, STA-ID BSS color), queue size, access category information, and / or packet type (e.g., control, management, data frame), etc. In some examples, the trigger request is received in response to the transmitter determining that the size of the data meets a threshold (e.g., a maximum size value that may be indicated by the receiver).

[0147] Based on the size of the data, the duration of the TB-PPDU is determined 1904. Then, a trigger is sent 1906 to the transmitter. The trigger indicates the duration of the transmission of the TB-PPDU. In some examples, before sending the trigger, an acknowledgment of the trigger request is sent to the transmitter. In some examples, a TB-PPDU is received from the transmitter, and the TB-PPDU is generated in part based on the duration. In some examples, the TB-PPDU is an ultra-high reliability TB-PPDU.

[0148] Fig. 20 A flowchart of an example method 2000 according to some specific implementations is illustrated. For clarity of presentation, the following description generally describes the method 2000 in the context of other figures in this specification. For example, the method 2000 may be performed by Figure 1 The method 2000 may be performed by one or more electronic devices in the electronic device 110. It should be understood that the method 2000 may be performed by any suitable system, environment, software, hardware, or a combination of systems, environments, software, and hardware, as appropriate. In some specific implementations, the steps of the method 2000 may be executed in parallel, in combination, in a loop, or in any order.

[0149] The operations of the method 2000 include receiving 2002 a non-high throughput physical protocol data unit (non-HT PPDU). In response to the non-HT PPDU, a control frame is sent 2004 using an ultra-high reliability extended range single user PPDU (UHR ER SU PPDU) format. In some examples, the non-HT PPDU is a request to send (RTS) and the control frame using the UHR ER SU PPDU format is a clear to send (CTS). In some examples, the control frame using the UHR ER SU PPDU format is sent in a repetitive transmission mode over a bandwidth greater than or equal to 20 MHz.

[0150] In some examples, the control frame is sent using a UHR ER SU PPDU format according to the operating mode. In some examples, the operating mode is negotiated based on the operating mode notification, the capability field, or the control response. In some examples, the operating mode is set according to an indication in a Quality of Service Null (QoS-NULL) frame (or another frame). The operating mode may remain unchanged until a negative indication occurs in a QoS-NULL frame.

[0151] Fig.21 A flowchart of an example method 2100 according to some specific implementations is illustrated. For clarity of presentation, the following description generally describes the method 2100 in the context of other figures in this specification. For example, the method 2100 may be performed by Figure 1 The method 2100 may be performed by one or more access points 112 of the system. It should be understood that the method 2100 may be performed by any suitable system, environment, software, hardware, or a combination of systems, environments, software, and hardware, as appropriate. In some specific implementations, the steps of the method 2100 may be executed in parallel, in combination, in a loop, or in any order.

[0152] The operations of the method 2100 include sending 2102 a non-high throughput physical protocol data unit (non-HT PPDU). In response to the non-HT PPDU, receiving 2104 a control frame using a UHR ER SU PPDU format. In some examples, the non-HT PPDU is an RTS and the control frame using the UHR ER SU PPDU format is a CTS. In some examples, the control frame using the UHR ER SU PPDU format is received in a repetitive transmission mode over a bandwidth greater than or equal to 20 MHz.

[0153] In some examples, the control frame is received using a UHR ER SU PPDU format according to the operating mode. In some examples, the operating mode is negotiated based on the operating mode notification, the capability field, or the control response. In some examples, the operating mode is set according to an indication in a Quality of Service Null (QoS-NULL) frame (or another frame). The operating mode may remain unchanged until a negative indication occurs in a QoS-NULL frame.

[0154] Fig. 22 A block diagram of an electronic device 2200 according to some implementations is illustrated. The electronic device 2200 may be a cellular phone, a smart watch, an access point, a wireless speaker, an Internet of Things (IoT) device, etc. The electronic device 2200 includes hardware resources 2202, which include one or more processors (or processor cores) 2210, one or more memory / storage devices 2220, and one or more communication resources 2230, each of which may be communicatively coupled via a bus 2240.

[0155] The one or more processors 2210 include one or more devices configured to perform computing operations. For example, the one or more processors 2210 may include one or more microprocessors, application specific integrated circuits (ASICs), microcontrollers, graphics processing units (GPUs), programmable logic devices, and / or one or more digital signal processors (DSPs). The processor 2210 may include, for example, a processor 2212 and a processor 2214. The processor 2210 may be, for example, a central processing unit (CPU), a reduced instruction set computing (RISC) processor, a complex instruction set computing (CISC) processor, a graphics processing unit (GPU), a DSP such as a baseband processor, an ASIC, an FPGA, a radio frequency integrated circuit (RFIC), another processor (including those discussed herein), or any suitable combination thereof.

[0156] The memory / storage device 2220 may include a main memory, a disk storage device, or any suitable combination thereof. The memory / storage device 2220 may include, but is not limited to, any type of volatile or non-volatile memory, such as a dynamic random access memory (DRAM), a static random access memory (SRAM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a solid-state storage device, etc. In some specific implementations, the memory / storage device 2220 is coupled to one or more high-capacity mass storage devices (not shown). In some examples, the memory / storage device 2220 may be coupled to a disk drive or an optical drive, a solid-state drive, or another type of mass storage device. In these examples, the memory / storage device 2220 may be used by the electronic device 2200 as a fast access storage device for frequently used data, while the mass storage device is used to store less frequently used data.

[0157] The communication resources 2230 may include an interconnect or network interface component or other suitable device to communicate with one or more peripheral devices 2204 or one or more databases 2206 via the network 2208. For example, the communication resources 2230 may include a wired communication component (e.g., for coupling via USB), a cellular communication component, an NFC component, (or Low power consumption) components, components and other communication components.

[0158] The communication resources 2230 include one or more devices configured to couple to and communicate on a wired and / or wireless network (i.e., perform network operations), such as: a control logic component, one or more interface circuits, and a group of antennas (or antenna elements) in an adaptive array that can be selectively turned on and / or off by the control logic component to produce a variety of optional antenna patterns or "beam patterns." Alternatively, in place of the group of antennas, in some examples, the electronic device 2200 includes one or more nodes (e.g., pads or connectors) that can be coupled to the group of antennas. Thus, the electronic device 2200 may or may not include the group of antennas. For example, the communication resources 2230 may include a Bluetooth TM networking systems, cellular networking systems (such as 3G / 4G / 5G / 6G networks such as UMTS, LTE, etc.), universal serial bus (USB) networking systems, IEEE 802.11-based (such as networking system), an Ethernet networking system, and / or another networking system.

[0159] In some implementations, the communication resources 2230 include one or more radio components, such as a wake-up radio component for receiving wake-up frames and wake-up beacons, and a main radio component for sending and / or receiving frames or packets during normal operating mode. The wake-up radio component and the main radio component can be implemented separately (such as using discrete components or separate integrated circuits) or in a common integrated circuit.

[0160] The communication resources 2230 may include processors, controllers, radios / antennas, sockets / plugs, and / or other devices for coupling to, communicating on, and processing data and events for each supported networked system. Note that the mechanisms for coupling to, communicating on, and processing data and events on the networks of network systems are sometimes collectively referred to as the "network interfaces" of the network systems.

[0161] The instructions 2250 may include software, programs, applications, applet, applications, or other executable code for causing at least any one of the processors 2210 to perform any one or more of the methods discussed herein. The instructions 2250 may reside in whole or in part in at least one of the processor 2210 (e.g., in a cache memory of the processor), the memory / storage device 2220, or any suitable combination thereof. In some implementations, any portion of the instructions 2250 may be sent to the hardware resource 2202 from any combination of the peripheral device 2204 or the database 2206. Therefore, the memory of the processor 2210, the memory / storage device 2220, the peripheral device 2204, and the database 2206 are examples of computer-readable and machine-readable media.

[0162] Although the foregoing discussion uses the Wi-Fi communication protocol as an illustrative example, in other specific implementations, a variety of communication protocols may be used, and more generally, wireless communication technologies may be used. Therefore, the communication technology may be used in a variety of network interfaces. In addition, although some of the operations in the foregoing specific implementations are implemented in hardware or software, generally speaking, the operations in the foregoing specific implementations may be implemented in a variety of configurations and architectures. Thus, some or all of the operations in the foregoing specific implementations may be performed in hardware, in software, or in a combination of both hardware and software. For example, at least some of the operations in the communication technology may be implemented using instructions 2250, an operating system (such as a driver for an interface circuit in the communication resource 2230), or in firmware in an interface circuit in the communication resource 2230. Additionally or alternatively, at least some of the operations in the communication technology may be implemented in a physical layer (such as hardware in an interface circuit in the communication resource 2230). In some specific implementations, the communication technology is implemented at least in part in a MAC layer and / or a physical layer in an interface circuit in the communication resource 2230.

[0163] Although the foregoing embodiments illustrate the use of wireless signals in one or more frequency bands, in some implementations, electromagnetic signals in one or more different frequency bands are used to determine distance. For example, these signals may be communicated in one or more frequency bands, including: microwave bands, radar bands, 900 MHz, 2.4 GHz, 5 GHz, 6 GHz, 60 GHz, and / or frequency bands used by Citizens Broadband Radio Service, LTE, 5G, or any other communication system.

[0164] Although the electronic device 2200 is described using specific components, in some implementations, different components and / or subsystems may be present in the electronic device 2200. For example, the electronic device 2200 may include one or more additional processing subsystems, memory subsystems, networking subsystems, and / or display subsystems. Additionally, one or more of the subsystems may not be present in the electronic device 2200. In some implementations, the electronic device 2200 may include Fig. 22 In some implementations, the electronic device may include an analysis subsystem that performs at least some of the operations in the communication technology. Fig. 22 Separate subsystems are shown in FIG. 2 , but in some implementations, some or all of a given subsystem or component may be integrated into one or more of the other subsystems or components in electronic device 2200 .

[0165] For one or more embodiments, at least one of the components shown in one or more of the foregoing figures may be configured to perform one or more operations, techniques, processes, or methods described in the following example section. For example, the baseband circuit described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the following examples. For another example, the circuits associated with the UE, base station, network element, etc. described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples shown in the example section below.

[0166] Unless explicitly stated otherwise, any of the above examples may be combined with any other example (or combination of examples). The foregoing description of one or more specific implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of the embodiments to the precise form disclosed. In view of the above teachings, modifications and variations are possible or can be obtained from the practice of various embodiments.

[0167] Although the above embodiments have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to include all such variations and modifications.

[0168] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

Claims

1. A method, comprising: generating an extended range physical layer protocol data unit (ER-PPDU) for transmission to a receiver, the ER-PPDU comprising an ultra high reliability extended range long training field (UHR-ER-LTF) and an ultra high reliability extended range signal field (UHR-ER-SIG); and The ER-PPDU is sent to the receiver, wherein at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated two or more times in the time domain or the frequency domain.

2. The method of claim 1 , wherein the ER-PPDU further comprises a legacy short training field (L-STF), a legacy long training field (L-LTF), and one or more additional fields between the L-LTF and the UHR-ER-LTF, the one or more additional fields comprising at least one of a legacy signal field (L-SIG), a repeated legacy signal field (RL-SIG), a universal signal field (U-SIG), or an ultra-high reliability short training field (UHR-STF). 3 . The method of claim 2 , wherein at least one of the L-STF or the L-LTF is power-boosted by 3 dB or more. 4 . The method of claim 1 , wherein the at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over an entire length of an orthogonal frequency division multiplexing (OFDM) symbol. 5 . The method of claim 4 , wherein the at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over the entire length of the OFDM symbol using every four subcarriers of the OFDM symbol.

6. The method of claim 4, wherein the OFDM symbol length including a guard interval comprises 16 microseconds. 7 . The method of claim 1 , wherein the at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated four times in the time domain or the frequency domain.

8. The method according to claim 1, further comprising: obtaining data for transmission to said receiver, The ER-PPDU further includes a data field, wherein the data field includes at least a portion of the data to be transmitted to the receiver. 9 . The method according to claim 8 , wherein the data field is repeated two or more times in the time domain or the frequency domain.

10. The method of claim 8, wherein the data field is modulated over the entire length of an OFDM symbol using every four subcarriers of the OFDM symbol.

11. The method according to claim 1, further comprising: A center frequency offset (CFO) correction is performed before transmitting the ER-PPDU, wherein a residual CFO after performing the CFO correction is less than or equal to 15 kHz.

12. The method according to claim 1, wherein the method is performed by a non-access point station (non-AP STA).

13. The method according to claim 1, further comprising: receiving, from the receiver, an indication of a maximum size of the ER-PPDU; as well as The ER-PPDU is generated according to the maximum size.

14. A device, comprising: one or more processors; as well as One or more storage devices storing instructions executable by the one or more processors to cause the one or more processors to perform operations including: generating an extended range physical layer protocol data unit (ER-PPDU) for transmission to a receiver, the ER-PPDU comprising an ultra high reliability extended range long training field (UHR-ER-LTF) and an ultra high reliability extended range signal field (UHR-ER-SIG); and The ER-PPDU is sent to the receiver, wherein at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated two or more times in the time domain or the frequency domain.

15. A method comprising: receiving an extended range physical layer protocol data unit (ER-PPDU), the ER-PPDU comprising an ultra high reliability extended range long training field (UHR-ER-LTF) and an ultra high reliability extended range signal field (UHR-ER-SIG), wherein at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated two or more times in the time domain or the frequency domain; and The ER-PPDU is processed to obtain information included in at least one of the UHR-ER-LTF or the UHR-ER-SIG.

16. The method of claim 15, wherein the ER-PPDU further comprises a legacy short training field (L-STF), a legacy long training field (L-LTF), and one or more additional fields between the L-LTF and the UHR-ER-LTF, the one or more additional fields comprising at least one of a legacy signal field (L-SIG), a repeated legacy signal field (RL-SIG), a universal signal field (U-SIG), or an ultra-high reliability short training field (UHR-STF), the method further comprising: The PPDU is processed to obtain information included in at least one of the L-STF, the L-LTF, or the one or more additional fields. 17 . The method of claim 16 , wherein at least one of the L-STF and the L-LTF is power-boosted by 3 dB or more.

18. The method of claim 15, wherein the at least one of the UHR-ER-LTF or the UHR-ER-SIG is modulated over an entire length of an orthogonal frequency division multiplexing (OFDM) symbol using every four subcarriers of the OFDM symbol.

19. The method of claim 15, wherein the at least one of the UHR-ER-LTF or the UHR-ER-SIG is repeated four times in the time domain or the frequency domain.

20. The method of claim 15, wherein the ER-PPDU further includes a data field repeated two or more times in the time domain or the frequency domain, the method further comprising: The ER-PPDU is processed to obtain information included in the data field.

Images