An integrated circuit that identifies the PPDU format

Abstract

To efficiently identify the format of a PPDU after HE (post high efficiency).SOLUTION: The present disclosure provides a communication device, a communication method, and an integrated circuit for identifying the format of a PPDU. The communication device includes: a circuit for generating a physical layer protocol data unit (PPDU) including a first signal field, a second signal field, and a third signal field, in operation, where the second signal field is used to determine whether a physical layer (PHY) version of the generated PPDU is not older than a specific PHY version, and the third signal field is used to indicate a PHY version of the generated PPDU; and a transmitter for transmitting the generated PPDU, in operation.SELECTED DRAWING: Figure 4D

Description

[Technical Field]

[0001] The present disclosure relates to an integrated circuit that identifies the format of a Physical Layer Protocol Data Unit (PPDU), and more particularly, to an integrated circuit that efficiently identifies the format of a post-High Efficiency (HE) PPDU. [Background technology]

[0002] In the standardization of next-generation wireless local area networks (WLANs), a new wireless access technology that is backward compatible with IEEE802.11a / b / g / n / ac / ax technologies is being considered within the IEEE802.11 working group and is named Extremely High Throughput (EHT) WLAN.

[0003] EHT WLANs are expected to increase the maximum channel bandwidth from 160 MHz to 320 MHz in order to provide a significant increase in peak throughput and capacity over 802.11ax high-efficiency (HE) WLANs.

[0004] However, no study has been conducted on a communication device and a communication method for identifying the format of a PPDU in an EHT WLAN environment.

[0005] Therefore, there is a need for a communication device and a communication method that provides a feasible technical solution for identifying the format of a PPDU in an EHT WLAN environment. Furthermore, other desirable features and characteristics will become apparent from the following detailed description and the appended claims, taken in conjunction with the accompanying drawings and the background technology herein. Summary of the Invention [Problem to be solved by the invention]

[0006] Non-limiting exemplary embodiments of the present invention facilitate providing a communication device, a communication method, and an integrated circuit that efficiently identifies the format of a post High Efficiency (HE) PPDU. [Means for solving the problem]

[0007] According to one embodiment of the present disclosure, there is provided a communications device comprising: a circuit that, in operation, generates a physical layer protocol data unit (PPDU) including a first signal field, a second signal field, and a third signal field, wherein the second signal field is used to determine whether a physical layer (PHY) version of the generated PPDU is older than a specific PHY version, and the third signal field is used to indicate the PHY version of the generated PPDU; and a transmitter that, in operation, transmits the generated PPDU.

[0008] It should be noted that the general or specific embodiments may be implemented as a system, a method, an integrated circuit, a computer program, a storage medium, or any combination thereof.

[0009] Further benefits and advantages of the disclosed embodiments will become apparent from the specification and drawings. These benefits and / or advantages may be obtained individually by the various embodiments and features of the specification and drawings, and it is not necessary for all of these features to be present in order to obtain one or more of such benefits and / or advantages. [Brief explanation of the drawings]

[0010] Embodiments of the present disclosure will be better understood and readily apparent to those of ordinary skill in the art upon reading the following description, given by way of example only, and upon reference to the drawings in which: [Figure 1A]1 illustrates a schematic diagram of uplink and downlink single-user multiple-input multiple-output (MIMO) communication between an access point (AP) and a station (STA) in a MIMO wireless network. [Figure 1B] 1 illustrates a schematic diagram of downlink multi-user MIMO communication between an AP and multiple STAs in a MIMO wireless network. [Figure 1C] 1 shows diagrams of some existing 802.11 pre-EHT PPDU formats. [Figure 2] 1 illustrates the format of a PPDU after HE according to various embodiments. [Figure 3] 10 illustrates another format of a PPDU after HE according to various embodiments. [Figure 4A] 1 shows a partially boxed schematic diagram of a communication device (eg, an AP or a STA) according to various embodiments. [Figure 4B] 1 shows a flow diagram illustrating a communication method according to various embodiments. [Figure 4C] 1 shows a flow diagram illustrating a communication method according to various embodiments. [Figure 4D] 1 shows a flow diagram illustrating a communication method according to various embodiments. [Figure 5] 1 shows an illustration of an example of generating a Coarse Identification sub-field according to a first embodiment; [Figure 6] 10 shows an illustration of another example of generating a Coarse Identification sub-field according to the first embodiment; [Figure 7] 1 shows the format of a Fine Identification subfield according to the first embodiment. [Figure 8] 3 shows a flow diagram illustrating the generation of a Fine Identification subfield according to a first embodiment; [Figure 9]1 shows a flow diagram illustrating processing in a STA or AP according to a first embodiment; [Figure 10] 10 shows the format of a Format Identification field (FIF) according to the second embodiment. [Figure 11] 10 shows a flow diagram illustrating the generation of FIF symbols according to a second embodiment; [Figure 12] 1 shows a scrambler. [Figure 13] 10 shows another format of FIF according to the second embodiment. [Figure 14] 10 shows a flow diagram illustrating processing in a STA or AP according to a second embodiment; [Figure 15] 1 illustrates a configuration of a communication device (eg, an AP or a STA) according to various embodiments.

[0011] Those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some elements in the illustrations, block diagrams, or flow charts may be exaggerated relative to other elements to facilitate an accurate understanding of embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] Some embodiments of the present disclosure will now be described, by way of example only, with reference to the following figures in which like reference numbers and characters indicate similar or equivalent elements:

[0013] In the following paragraphs, certain exemplary embodiments are described in the context of an access point (AP) and a station (STA) for communications involving a post-HE PPDU.

[0014] In the context of IEEE 802.11 (Wi-Fi) technology, a station (also synonymously referred to as a STA) is a communication device capable of using the 802.11 protocol. Based on the definition in IEEE 802.11-2016, a STA can be any device that includes an IEEE 802.11-compliant medium access control (MAC) and physical layer (PHY) interface to the wireless medium (WM).

[0015] An STA may be, for example, a notebook, desktop personal computer (PC), personal digital assistant (PDA), access point, or Wi-Fi phone in a wireless local area network (WLAN) environment. An STA may be stationary or mobile. In a WLAN environment, the terms "STA," "wireless client," "user," "user device," and "node" are often used synonymously.

[0016] Similarly, an AP (also synonymously called a Wireless Access Point (WAP) in the context of IEEE 802.11 (Wi-Fi) technology) is a communications device that allows STAs in a WLAN to connect to a wired network. APs are typically connected (through the wired network) to a router as a standalone device, but APs can also be integrated with or used within a router.

[0017] As mentioned above, a STA in a WLAN can function as an AP at other times, and vice versa. This is because a communication device in the context of IEEE 802.11 (Wi-Fi) technology can include both STA and AP hardware elements. In this way, the communication device can switch between STA mode and AP mode based on the conditions and / or requirements of the actual WLAN.

[0018] In a MIMO wireless network, "multiple" refers to multiple antennas used simultaneously for transmission over a wireless channel and multiple antennas used simultaneously for reception. In this regard, "multiple-input" refers to multiple transmitter antennas that input wireless signals into a channel, and "multiple-output" refers to multiple receiver antennas that receive wireless signals from the channel into a receiver. For example, in an N×M MIMO network system, N is the number of transmitter antennas and M is the number of receiver antennas, and N may or may not be equal to M. For purposes of brevity, this disclosure will not further discuss the number of transmitter antennas and the number of receiver antennas.

[0019] In a MIMO wireless network, single-user and multi-user communication can be provided for communication between communication devices such as APs and STAs.

[0020] 1A illustrates a schematic diagram of single-user (SU) MIMO communication 100 between an AP 102 and a STA 104 in a MIMO wireless network. As illustrated, the MIMO wireless network may include one or more STAs (e.g., STA 104, STA 106, etc.). In SU MIMO communication 100, the AP 102 transmits multiple spatial streams using multiple antennas (e.g., four antennas as illustrated in FIG. 1A), with all spatial streams directed to a single communication device (i.e., STA 104). For simplicity, the multiple spatial streams directed to STA 104 are illustrated as a combined data transmission arrow 108 directed to STA 104.

[0021] SU-MIMO communication 100 can be configured for bidirectional transmission. As shown in FIG. 1A, in SU-MIMO communication 100, STA 104 can transmit multiple spatial streams using multiple antennas (e.g., two antennas as shown in FIG. 1A), with all spatial streams directed to AP 102. For simplicity, the multiple spatial streams directed to AP 102 are shown as a combined data transmission arrow 110 directed to AP 102.

[0022] Thus, the SU-MIMO communication 100 depicted in FIG. 1A enables both uplink single-user transmissions and downlink single-user transmissions in a MIMO wireless network.

[0023] FIG. 1B illustrates a schematic diagram of downlink multi-user (MU) MIMO communication 120 between an AP 122 and multiple STAs 124, 126, 128 in a MIMO wireless network.

[0024] The MIMO wireless network may include one or more STAs (e.g., STA 124, STA 126, STA 128, etc.). In downlink MU-MIMO communication 120, AP 122 uses multiple antennas via spatial mapping or precoding techniques to simultaneously transmit multiple streams to STAs 124, 126, and 128 within the network. For example, two spatial streams may be directed to STA 126, another spatial stream may be directed to STA 124, and yet another spatial stream may be directed to STA 128. For simplicity, the two spatial streams directed to STA 126 are shown as a combined data transmission arrow 132, the spatial stream directed to STA 124 is shown as data transmission arrow 130, and the spatial stream directed to STA 128 is shown as data transmission arrow 134.

[0025] Due to the packet / PPDU (Physical Layer Protocol Data Unit) based transmission and distributed MAC scheme in 802.11 WLAN, there is no time scheduling (e.g., periodic allocation of time slots for data transmission as in TDMA (Time Division Multiple Access)). Scheduling of frequency and spatial resources is performed on a packet basis. In other words, resource allocation information is PPDU-based.

[0026] 802.11n (WiFi 4) technology actually uses HT (High Throughput) mixed format PPDUs for uplink or downlink single-user transmission. With 40 MHz channel bandwidth and SU-MIMO transmission support, 802.11n technology can provide higher system throughput than 802.11a / b / g technology. Note that 802.11a / b / g technology uses non-HT PPDUs for uplink or downlink single-user communication.

[0027] 802.11ac (WiFi 5) technology uses VHT (Very High Throughput) PPDU for single-user transmission on the uplink or downlink and multi-user transmission on the downlink (e.g., full-bandwidth MU-MIMO transmission). With support for 160 MHz channel bandwidth and MU-MIMO transmission, 802.11ac technology can provide much higher system throughput than 802.11n technology.

[0028] 802.11ax (WiFi 6) technology has three main types of HE PPDUs: HE SU PPDU, HE MU PPDU, and HE TB (Trigger-Based) PPDU. HE SU PPDUs are used for single-user transmissions on the uplink or downlink. HE MU PPDUs are primarily used for downlink multi-user transmissions, such as OFDMA (Orthogonal Frequency Division Multiple Access) transmissions, including MU-MIMO transmissions on a single resource unit (RU) and full-bandwidth MU-MIMO transmissions. HE TB PPDUs are used for uplink multi-user transmissions, such as OFDMA transmissions, including MU-MIMO transmissions on a single resource unit (RU) and full-bandwidth MU-MIMO transmissions. Support for OFDMA allows 802.11ax technology to improve system throughput in high-density AP and / or STA scenarios compared to 802.11ac technology.

[0029] Similar to 802.11ax (WiFi 6) technology, there are three main types of EHT PPDUs: EHT SU PPDU, EHT MU PPDU, and EHT TB PPDU. The EHT SU PPDU is used for single-user transmissions on the uplink or downlink. The EHT MU PPDU is primarily used for downlink multi-user transmissions, such as OFDMA transmissions, including single-RU MU-MIMO and full-bandwidth MU-MIMO. The EHT TB PPDU is used for uplink multi-user transmissions, such as OFDMA transmissions, including single-RU MU-MIMO and full-bandwidth MU-MIMO. Because of its support for 320 MHz channel bandwidth, 16 spatial streams, and multi-band operation, EHT technology can significantly increase system throughput compared to 802.11ax technology.

[0030] FIG. 1C shows a diagram 150 of several existing 802.11 pre-EHT PPDU formats. A pre-EHT PPDU refers to an HE PPDU, a VHT PPDU, an HT PPDU, or a non-HT PPDU. Various fields can be BPSK (Binary Phase Shift Keying) modulated, as indicated by horizontal lines 152 in the respective fields. Various fields can be QBPSK (Quadrature Binary Phase Shift Keying) modulated, as indicated by vertical lines 154 in the respective fields. Various PPDUs include an L-SIG (non-HT SIGNAL field) (as indicated by column 156 in FIG. 1C). The RATE field of the L-SIG in an HT mixed format PPDU, a VHT PPDU, or an HE PPDU is set to "1101" for a rate of 6 Mbps. The LENGTH field of the L-SIG in an HT mixed format PPDU 158 or a VHT PPDU 162 is set to a value divisible by 3. The LENGTH field of the L-SIG in an HE PPDU 164, 168 is set to a value not divisible by 3. The value of the L-SIG LENGTH field, when divided by 3, has a remainder of 1 for an HE MU PPDU 164 and a remainder of 2 otherwise. To distinguish an HE SU PPDU from an HE TB PPDU 168, the value of the Format field in the HE-SIG-A (High Efficiency SIGNAL A field) is used. Note that HE PPDUs 164 and 168 have an RL-SIG (repeated non-HT SIGNAL field) after the L-SIG, VHT PPDU 162 has a VHT-SIG-A (Very High Throughput SIGNAL A field) after the L-SIG, and non-HT PPDUs have a SERVICE field in the Data field after the L-SIG.

[0031] According to various embodiments, a method and apparatus can be provided for efficiently identifying the format of a post-HE PPDU. A post-HE PPDU can refer to an EHT PPDU or a future PPDU that is backward compatible with the EHT PPDU and any pre-EHT PPDU. It should be understood that if the IEEE 802.11 working group uses a new name other than "EHT WLAN" for next-generation WLANs with extremely high throughput, the prefix "EHT" in the above fields may change accordingly.

[0032] According to various embodiments, two levels of PPDU format identification may be provided: Coarse PPDU format identification may be provided to identify whether a received PPDU is a post-HE PPDU; Fine PPDU format identification may be provided to double-check whether a received PPDU is a post-HE PPDU and, if so, identify its format; According to various embodiments, PPDU format identification may be provided to determine whether the physical layer (PHY) version of a generated PPDU is older than a specific PHY version and to indicate the PHY version of the generated PPDU.

[0033] 2 illustrates the format of a post-HE PPDU 200 according to various embodiments. In various embodiments, the post-HE PPDU is an EHT PPDU or a future PPDU that is backward compatible with the EHT PPDU and any pre-EHT PPDU. The post-HE PPDU 200 may include a non-High Throughput Short Training Field (L-STF) 202 and a non-High Throughput (non-HT) Long Training Field (L-LTF) 204. According to the present disclosure, the post-HE PPDU 200 may further include a non-High Throughput (non-HT) Signal Field (L-SIG) 206, a Format Identification Field (FIF) 208, a SIGNAL A Field (SIG-A) 210, and an additional field 212. The post-HE PPDU 200 may include an FIF 208 after the L-SIG 206, which may include one OFDM symbol having a duration of 4 μs including 48 data tones, 4 pilot tones, and 4 extension tones, and may be BPSK modulated. The FIF 208 may include information used for both coarse PPDU format identification and fine PPDU format identification.

[0034] The SIG-A field 210 and the further field 212 may vary according to the format of the PPDU and can be decoded based on the PPDU format detail identification.

[0035] Furthermore, the RATE field of L-SIG206 in PPDU200 after HE is set to "1101" for a rate of 6 Mbps, just like the HE PPDU, and the LENGTH field of L-SIG206 in PPDU200 after HE is set to a value that is not divisible by 3, which can also be used for further identification of the PPDU format.

[0036] Various embodiments can efficiently provide format identification for any post-HE PPDU. Additionally, one symbol (i.e., the FIF 208 symbol) is used by the post-HE PPDU 200 for PPDU format identification purposes, resulting in overhead comparable to that of a HE PPDU using one RL-SIG symbol.

[0037] 3 illustrates another format of a post-HE PPDU 300 according to various embodiments. The post-HE PPDU may be an EHT PPDU or a future PPDU that is backward compatible with the EHT PPDU and any pre-EHT PPDU. The post-HE PPDU 300 may include fields similar to or identical to those of the post-HE PPDU 200, including an L-STF 302, an L-LTF 304, a first signal field such as an L-SIG field, an FIF 308, and a SIG-A field 310. The FIF 308 may include a second signal field such as a Coarse Identification subfield 314 and a third signal field such as a Fine Identification subfield 316. The Coarse Identification subfield 314 can be used for coarse identification of the PPDU format (i.e., used to determine whether the PHY version of the PPDU 300 after HE is older than a specific PHY version (e.g., EHT PPDU)) and can be generated according to a predetermined subset of tones of the L-SIG symbol. The predetermined subset of tones can include N data tones (8≦N≦32, where N is an integer). Alternatively, the predetermined subset of tones can include N data tones, M pilot tones, and L extension tones (M=4 and N=4). The N data tones can be selected from the 48 data tones such that the N data tones are distributed as evenly as possible across the entire transmission bandwidth. The Fine Identification subfield 316 can be used for fine identification of the PPDU format (i.e., used to indicate the PHY version of the PPDU 400 after HE).

[0038] In particular, a third signal field (e.g., Fine Identification subfield 316) can be used to indicate the PHY version of the PPDU 300 after HE. In various embodiments, the Fine Identification subfield 316 can include version-independent bits with a defined number of bits and a static position within the field. The version-independent bits can include, for example, a PHY version identifier, an uplink / downlink flag, a basic service set (BSS) color, and a transmit opportunity (TXOP) duration. The PHY version identifier is used to identify the exact PHY version starting with 802.11be. Furthermore, the Fine Identification subfield 316 can include version-dependent bits following the version-independent bits. In one embodiment, the version-dependent bits following the version-independent bits have a variable number of bits depending on the PHY version. The version-dependent bits can include, for example, a PPDU format, a SU / MU flag, and a bandwidth (BW).

[0039] According to various embodiments, the FIF 308 is a repetition of the L-SIG field 306. In particular, the FIF 308 is mapped to tones, and each value of the FIF 308 in a portion of the tones is generated according to the corresponding value of the L-SIG field 306 in that portion of the tone. In one embodiment, each value of the FIF 308 in a portion of the tones is inverted from the corresponding value of the L-SIG field 306 in that portion of the tone. The tones may be data tones or data subcarriers. For example, the Coarse Identification subfield 314 may be generated using tone value inversion and tone mapping. Tone value inversion may invert the values ​​of a predetermined subset of tones in the L-SIG symbol. Tone mapping may map the inverted values ​​of a predetermined subset of tones in the L-SIG symbol to the same tones in the FIF symbol.

[0040] 4A illustrates a partially boxed schematic diagram of a communications device 400 according to various embodiments, which may be implemented as an AP or a STA according to various embodiments.

[0041] As shown in Figure 4A, the communications device 400 may include circuitry 414, at least one wireless transmitter 402, at least one wireless receiver 404, and multiple antennas 412 (for simplicity, only one antenna is depicted in Figure 4A for illustrative purposes). The circuitry 414 may include at least one controller 406, which is used in carrying out the tasks it is designed to perform with the assistance of software and hardware, including controlling communications with one or more other communications devices in a MIMO wireless network. The circuitry 414 may further include at least one transmit signal generator 408 and at least one receive signal processor 410. The at least one controller 406 can control the at least one transmit signal generator 408 to generate PPDUs (e.g., post-HE PPDUs) to be sent to one or more other communication devices through the at least one wireless transmitter 402, and can also control the at least one receive signal processor 410 to process PPDUs received from one or more other communication devices through the at least one wireless receiver 404 under the control of the controller 406. The at least one transmit signal generator 408 and the at least one receive signal processor 410 can be standalone modules of the communication device 400 that communicate with the at least one controller 406 for the functions described above, as shown in FIG. 4A . Alternatively, the at least one transmit signal generator 408 and the at least one receive signal processor 410 can be included in the at least one controller 406. It will be appreciated by those skilled in the art that the arrangement of these functional modules is flexible and can be changed according to actual needs and / or requirements. Data processing, storage, and other related control devices can be provided on an appropriate circuit board and / or chipset. In various embodiments, in operation, at least one wireless transmitter 402 , at least one wireless receiver 404 , and at least one antenna 412 may be controlled by at least one controller 406 .

[0042] For example, the communication device 400 may be an AP or a STA, and the circuit 414 (e.g., the transmit signal generator 408 of the circuit 414), in operation, generates a transmit signal, e.g., a physical layer protocol data unit (PPDU) including a legacy signal field and a non-legacy signal field, where the legacy signal field includes orthogonal frequency division multiplexing (OFDM) symbols. The wireless transmitter 402, in operation, may transmit the generated transmit signal (e.g., the PPDU). The non-legacy signal field may include OFDM symbols and may include information used for coarse PPDU format identification and detailed PPDU format identification. The coarse PPDU format identification may include identifying a post-HE (post-High Efficiency) PPDU, and the detailed PPDU format identification may include identifying the format of the post-HE PPDU.

[0043] The non-legacy signal field may include a first subfield used for coarse PPDU format identification and a second subfield used for fine PPDU format identification, the first subfield being formatted according to a subset of the tones of the symbols of the legacy signal field.

[0044] The second subfield may contain signaling to indicate the format of the PPDU after HE, and is mapped to tones of symbols in the non-legacy signal field that are different from the predetermined subset of tones.

[0045] The first subfield may include a subset of tones of symbols in the non-legacy signal field, where the values ​​of the subset of tones are inverted from the values ​​of corresponding tones of symbols in the legacy signal field. The subset of tones of symbols in the non-legacy signal field may be determined such that the subset of tones is distributed as evenly as possible across the entire transmission bandwidth. The subset of tones of symbols in the non-legacy signal field may be determined based on a predetermined number of least significant bits (LSBs) of the legacy signal field. The first subfield may include a signature sequence. A pattern of the subset of consecutive bits in the signature sequence may be different from a pattern of the corresponding subset of bits in a repeating non-HT signal field (RL-SIG) of the high efficiency PPDU (HE).

[0046] According to various embodiments, the transmit signal generator 408 of the circuit, in operation, can generate a post-HE PPDU that includes a legacy signal field followed by a non-legacy signal field, the legacy signal field including one OFDM symbol. The wireless transmitter 402, in operation, can transmit the generated PPDU. The non-legacy signal field includes one OFDM symbol and includes information used for both coarse PPDU format identification and fine PPDU format identification.

[0047] The non-legacy signal field may include a first subfield used for coarse PPDU format identification and a second subfield used for fine PPDU format identification, the first subfield being formatted according to a predetermined subset of tones of the symbols of the legacy signal field (e.g., according to the first embodiment).

[0048] The first sub-field may include a subset of predetermined tones of the symbols of the non-legacy signal field, the values ​​of the predetermined tones being inverted from the values ​​of the corresponding tones of the symbols of the legacy signal field.

[0049] The second subfield may contain signaling to indicate the format of the PPDU after HE, and is mapped to tones of symbols in the non-legacy signal field that are different from the predetermined subset of tones.

[0050] The non-legacy signal field may include a first subfield used for coarse PPDU format identification and a second subfield used for fine PPDU format identification, the first subfield including a signature sequence (e.g., according to the second embodiment).

[0051] The pattern of a subset of consecutive bits in the signature sequence may be different from the pattern of the corresponding subset of bits in the RL-SIG of the HE PPDU.

[0052] For example, the communication device 400 may be an AP or a STA, and the circuit 414 (e.g., the transmit signal generator 408 of the circuit 414) may, in operation, generate a transmit signal (e.g., a PPDU) including a first signal field, a second signal field, and a third signal field, where the second signal field is used to determine whether the physical layer (PHY) version of the generated PPDU is older than a specific PHY version, and the third signal field is used to indicate the PHY version of the generated PPDU. The wireless transmitter 402 may, in operation, transmit the generated transmit signal (e.g., a PPDU). In one embodiment, the PPDU of the specific PHY version is an EHT PPDU.

[0053] The third signal field can include version-independent bits having a fixed number of bits and a static position within the third signal field. In one embodiment, the generated PPDU includes version-dependent bits following the version-independent bits. In another embodiment, the version-dependent bits have a variable number of bits.

[0054] The second signal field may be a repetition of the first signal field. In one embodiment, the second signal field is mapped to a tone, and each value of the second signal field in a portion of the tone is generated according to the corresponding value of the first signal field in that portion of the tone. In another embodiment, each value of the second signal field in a portion of the tone may be the inverse of the corresponding value of the first signal field in that portion of the tone. In yet another embodiment, the tone is a data subcarrier.

[0055] In various embodiments, the second signal field and the third signal field can be encoded within one OFDM symbol, and the first signal field and the second signal field can be used to determine if the PHY version of the generated PPDU is older than a particular PHY version.

[0056] For example, the communication device 400 may be an AP or a STA, and the wireless receiver 404, in operation, may receive a transmission signal (e.g., a PPDU (Physical Layer Protocol Data Unit)) including a legacy signal field and a non-legacy signal field, where the legacy signal field includes an OFDM (Orthogonal Frequency Division Multiplexing) symbol. Furthermore, the circuit 414 (e.g., the receive signal processor 410 of the circuit 414), in operation, processes the received transmission signal. The non-legacy signal field may include an OFDM symbol and includes information used for coarse PPDU format identification and detailed PPDU format identification. The coarse PPDU format identification may include identifying a post-HE (post-High Efficiency) PPDU, and the detailed PPDU format identification may include identifying the format of the post-HE PPDU.

[0057] The non-legacy signal field may include a first subfield used for coarse PPDU format identification and a second subfield used for fine PPDU format identification, the first subfield being formatted according to a subset of the tones of the symbols of the legacy signal field.

[0058] The second subfield may include signaling for indicating the format of the PPDU after HE, and is mapped to tones of the symbols of the non-legacy signal field that are different from the predetermined subset of tones. The first subfield may include a subset of tones of the symbols of the non-legacy signal field, where the tone values ​​of the subset of tones are inverted from the values ​​of the corresponding tones of the symbols of the legacy signal field. The subset of tones of the symbols of the non-legacy signal field may be determined such that the subset of tones is distributed as evenly as possible across the entire transmission bandwidth. The subset of tones of the symbols of the non-legacy signal field may be determined based on a predetermined number of least significant bits (LSBs) of the legacy signal field.

[0059] According to various embodiments, the first subfield may include a signature sequence, wherein the pattern of a subset of consecutive bits in the signature sequence may be different from the pattern of a corresponding subset of bits in a repeating non-HT signal field (RL-SIG) of the high efficiency (HE) PPDU.

[0060] 4B shows a flow diagram 430 illustrating a communication method according to various embodiments. At 432, a transmission signal (e.g., a physical layer protocol data unit (PPDU)) may be generated. The transmission signal may include a legacy signal field and a non-legacy signal field. The legacy signal field may include orthogonal frequency division multiplexing (OFDM) symbols. At 434, the generated transmission signal (e.g., a PPDU) may be transmitted. The non-legacy signal field may include OFDM symbols and may include information used for coarse PPDU format identification and detailed PPDU format identification. The coarse PPDU format identification may include identifying a post-High Efficiency (HE) PPDU. The detailed PPDU format identification may include identifying the format of the post-HE PPDU.

[0061] 4C shows a flow diagram 460 illustrating a communication method according to various embodiments. At 462, a transmission signal (e.g., a PPDU (Physical Layer Protocol Data Unit)) can be received. The transmission signal can include a legacy signal field and a non-legacy signal field. The legacy signal field can include an OFDM (Orthogonal Frequency Division Multiplexing) symbol. At 464, the received transmission signal can be processed. The non-legacy signal field can include an OFDM symbol and can include information used for coarse PPDU format identification and detailed PPDU format identification. The coarse PPDU format identification can include identifying a post-HE (post-High Efficiency) PPDU, and the detailed PPDU format identification can include identifying the format of the post-HE PPDU.

[0062] 4D shows a flow diagram 470 illustrating a communication method according to various embodiments. At 472, a transmission signal (e.g., a PPDU) can be generated. The PPDU includes a first signal field, a second signal field, and a third signal field, where the second signal field is used to determine whether the PHY version of the generated PPDU is older than a particular PHY version, and the third signal field is used to indicate the PHY version of the generated PPDU. The second signal field and the third signal field can be encoded in one OFDM symbol. At 474, the generated PPDU can be transmitted.

[0063] FIG. 5 shows an example diagram 500 of generating the Coarse Identification subfield 314 according to the first embodiment. The tones of the L-SIG symbol 502 and the tones of the FIF symbol 504 are shown. Data tones for fine identification are shown by dotted lines 508. Data tones for coarse identification are shown by thin solid lines 510. Pilot and extension tones for coarse identification are shown by thick solid lines 512. Tone value inversion 506 is applied only to the data tones for coarse identification and the pilot and extension tones. In the example shown in FIG. 5, the predetermined subset of tones includes N=24 data tones (for coarse identification), M=4 pilot tones, and L=4 extension tones. A total of 32 tones are provided for coarse identification, and the tone indices of the Coarse Identification subfield are {±28, ±27, ±26, ±24, ±22, ±21, ±19, ±17, ±15, ±13, ±11, ±9, ±7, ±6, ±4, ±2}. As can be seen from FIG. 5 , the subset of tones of the FIF symbol 504 used for coarse identification is determined so that they are distributed as evenly as possible across the entire transmission bandwidth. In such an embodiment, the Coarse Identification subfield can be generated according to the corresponding L-SIG symbol 502 in the subset of tones that includes data tones for PPDU format coarse identification. The Coarse Identification subfield is used to determine whether the PHY version of the PPDU is older than a specific PHY version (e.g., EHT PPDU). In another embodiment, the L-SIG symbol 502 and the Coarse Identification subfield can be used to determine if the PHY version of the PPDU is older than a particular PHY version.

[0064] FIG. 6 shows another example diagram 600 of generating the Coarse Identification subfield 314 according to the first embodiment. The tones of the L-SIG symbol 608 and the tones of the FIF symbol 610 are shown. Data tones for fine identification are shown by dotted lines 614. Data tones for coarse identification are shown by thin solid lines 616. Pilot and extension tones are shown by thick solid lines 618. In the example shown in FIG. 6, the predetermined subset of tones includes N=10 data tones corresponding to the five least significant bits (LSBs) 602 of the L-SIG field. The five LSBs 602 of the L-SIG are fixed to "11010" because the RATE field of the L-SIG field is set to "1101" for a rate of 6 Mbps and the Reserved field of the L-SIG field is set to "0." After rate 1 / 2 BCC (binary convolutional code) encoding, these bits correspond to 1110101110 (bit sequence 604 in FIG. 6). Thus, after interleaving and BPSK modulation 606, the theoretical value of a given subset of tones in an L-SIG symbol is "+1 +1 +1 -1 +1 -1 +1 +1 +1 -1" (as shown in L-SIG symbol 608). Therefore, the values ​​of a given subset of tones in an FIF symbol 610 can be compared with the theoretical values ​​of the same tones in an L-SIG symbol (in other words, with values ​​based on a predetermined number of LSBs of the L-SIG field) instead of the actual values ​​of the same tones in the L-SIG symbol. Tone value inversion 612 is applied only to data tones for coarse identification. A total of 10 tones are provided for coarse identification, and the tone indices of the Coarse Identification subfield are {-25, -22, -18, -15, -12, -9, -5, -2, +2, +5}. Similarly, in such an embodiment, the Coarse Identification subfield can be generated according to the corresponding L-SIG symbol 608 in the subset of tones that includes the data tones for PPDU format coarse identification, derived from the L-SIG field LSB 602.The Coarse Identification subfield can be used to determine if the PHY version of the PPDU is older than a particular PHY version. In one embodiment, the L-SIG symbol 608 and the Coarse Identification subfield can be used to determine if the PHY version of the PPDU is older than a particular PHY version.

[0065] 7 shows the format of a Fine Identification subfield 700 according to the first embodiment. The Fine Identification subfield 700 may include a Format field 702, a CRC (Cyclic Redundancy Check) field 704, and tail bits 706. The Format field 702 (which may include L bits) may indicate the format of the PPDU after HE (i.e., the PHY version of the PPDU after HE). For example, a value of 0 in the Format field may be used to indicate an EHT PPDU, and values ​​of 1 to 2 may be used to indicate an EHT PPDU. L Values ​​up to -1 may be reserved for future use. In another example, a value of 0 in the Format field may be used to indicate an EHT MU PPDU, a value of 1 in the Format field may be used to indicate an EHT SU PPDU or an EHT TB PPDU, and so on. L Values ​​up to -1 may be reserved for future use. The CRC field (which may contain 18-N / 2-L bits) may be calculated over the bits of the Format field. The tail bits 706 (which may contain 6 bits) may be set to all 0. For example, if N=24 and L=4, then the Format field 702 contains 4 bits, the CRC field 704 contains 2 bits, and the tail bits 706 contains 6 bits.

[0066] 8 shows a flow chart 800 illustrating generation of a Fine Identification subfield according to a first embodiment. In step 802, the (24-N / 2)-bit Fine Identification subfield may be coded with rate 1 / 2 BCC to generate 48-N coded bits. In step 804, the 48-N coded bits may be interleaved. In step 806, the 48-N interleaved bits may be BPSK modulated. In step 808, the 48-N BPSK symbols may be mapped to the remaining 48-N data tones.

[0067] The following describes a process for identifying the format of a PPDU using the FIF 308, particularly determining whether the PHY version of the PPDU is older than a particular PHY version. FIG. 9 shows a flow chart 900 illustrating processing at a STA or AP according to a first embodiment. A coarse identification of the PPDU format can be provided as indicated by the dotted box 902. A fine identification of the PPDU format can be provided as indicated by the dotted box 904. Processing can begin at 906. At 908, a tone value of the FIF symbol corresponding to the Coarse Identification subfield can be retrieved (e.g., by determining the tone as described with reference to FIG. 5, or by determining the tone according to a predetermined number of LSBs of the L-SIG as described with reference to FIG. 6). At 910, the retrieved tone value can be inverted. At 912, it can be determined whether the inverted value of the retrieved tone matches the value of the same tone of the L-SIG symbol. If it is determined that the inverted value of the retrieved tone matches the value of the same tone in the L-SIG symbol, processing may continue at 914. If it is determined that the inverted value of the retrieved tone does not match the value of the same tone in the L-SIG symbol, processing may continue at 926. At 914, the L-SIG symbol may be demodulated and decoded. At 916, it may be determined whether a parity check passes. If it is determined that the parity check passes, processing may continue at 918. If it is determined that the parity check does not pass, processing may continue at 926. At 918, it may be determined whether the RATE field of the L-SIG is set to "1101" for a rate of 6 Mbps. If it is determined that the RATE field of the L-SIG is set to "1101," processing may continue at 920. If it is determined that the RATE field of the L-SIG is not set to "1101," processing may continue at 926.At 920, it may be determined whether the value of the LENGTH field of the L-SIG is evenly divisible by three. If it is determined that the value of the LENGTH field of the L-SIG is not evenly divisible by three, processing may continue at 922. If it is determined that the value of the L-SIG is evenly divisible by three, processing may continue at 926. At 922, the tones of the FIF symbol corresponding to the Fine Identification subfield may be demodulated and decoded. At 924, it may be determined whether the CRC check passes. If it is determined that the CRC check passes, processing may continue at 928. If it is determined that the CRC check does not pass, processing may continue at 926. At 928, the format of the received PPDU may be identified based on the value of the Format field. At 926, processing may proceed to identifying the format of the PPDU before EHT. Processing may end at 930.

[0068] 10 shows the format of an FIF 1000 according to the second embodiment. The FIF 1000 can include a Signature Sequence subfield 1002, a Format subfield 1004, a CRC subfield 1006, and tail bits 1008. The Signature Sequence subfield 1002 can include N bits (8≦N≦16). The Format subfield 1004 can include L bits and can indicate the format of the PPDU after HE (1≦L≦5). For example, a value of 0 in the Format subfield can be used to indicate an EHT PPDU, and values ​​of 1 to 2 can be used to indicate an EHT PPDU. L Values ​​up to -1 may be reserved for future use. In another example, a value of 0 may be used to indicate an EHT MU PPDU, a value of 1 may be used to indicate an EHT SU PPDU or an EHT TB PPDU, and values ​​from 2 to 2 LValues ​​up to -1 may be reserved for future use. The CRC subfield 1006 may include 18-NL bits and may be calculated over the Signature Sequence bits and Format bits. The tail bits 1008 may include 6 bits and may be set to all 0. The Signature Sequence subfield 1002 and the CRC subfield 1006 may be used for coarse PPDU format identification, and the Format subfield 1004 may be used for fine PPDU format identification. For example, if N=8 and L=6, the Signature Sequence subfield 1002 may include 8 bits, the Format subfield 1004 may include 6 bits, the CRC subfield 1006 may include 4 bits, and the tail bits 1008 may include 6 bits.

[0069] FIG. 11 shows a flow chart 1100 illustrating the generation of FIF symbols according to a second embodiment. The FIF symbols can be generated in the same manner as the RL-SIG symbols of the HE PPDU. At 1102, the 24-bit FIF can be coded with rate 1 / 2 BCC to generate 48 coded bits. At 1104, the 48 coded bits can be interleaved. At 1106, the 48 interleaved bits can be BPSK modulated. At 1108, the 48 BPSK symbols can be mapped to 48 data tones. Therefore, the FIF symbols can be demodulated and decoded in the same manner as the RL-SIG symbols, resulting in a very low probability of falsely detecting the HE PPDU as a post-HE PPDU.

[0070] To reduce the probability of falsely detecting an HE PPDU as a post-HE PPDU, it is desirable for the bits of the signature sequence to have at least one bit that is different from the corresponding information bit of the RL-SIG (which is provided after the L-SIG in the HE PPDU and therefore may be in the same position as the FIF in various embodiments).

[0071] According to various embodiments, the signature sequence may include a pattern of a subset of consecutive bits in the signature sequence that is different from the pattern of the corresponding subset of bits in the RL-SIG.

[0072] As a first example, note that the third bit (B3) of the RL-SIG is fixed at "1" regardless of the rate. Thus, an 8-bit signature sequence could be "XXX0XXXX" (where X is either 0 or 1), and such a signature sequence would be different from the RL-SIG (because at least the third bit is different).

[0073] As a second example, note that bits 0 through 3 [B0:B3] in the RL-SIG are "1101" for a rate of 6 Mbps. Thus, an 8-bit signature sequence could be "0010XXXX" (where X is 0 or 1), and such a signature sequence would be different from the RL-SIG representing a rate of 6 Mbps (because at least bits [B0:B3] are different). This second example signature sequence may be more robust than the first example signature sequence (e.g., because of the larger number of different bits).

[0074] Note that in the third example, the fourth bit (B4) in the RL-SIG is a reserved bit and is currently fixed at 0. Thus, an 8-bit signature sequence could be "00101XXXX" (where X is 0 or 1), and such a signature sequence would differ from the RL-SIG (because at least bits [B0:B3] and B4 are different). This third example signature sequence may be even more robust than the second example signature sequence (e.g., because of the larger number of different bits).

[0075] To reduce the probability of falsely detecting a VHT PPDU as a post-HE PPDU, it is desirable for the bits of the signature sequence to have at least one bit that is different from the corresponding information bit of the VHT-SIG-A1 (which is provided after the L-SIG in the VHT PPDU and therefore may be in the same position as the FIF in various embodiments).

[0076] According to various embodiments, a signature sequence can be provided that includes a pattern of a first subset of consecutive bits that is different from the pattern of the corresponding subset of bits in the RL-SIG, and the pattern of a second subset of consecutive bits in the signature sequence can be different from the pattern of the corresponding subset of bits in the VHT-SIG-A1.

[0077] Note that [B0:B1] in the RL-SIG, representing a rate of 6 Mbps, is "11," and that in VHT-SIG-A1, B2 is a reserved bit and is currently fixed at "1." Furthermore, note that in VHT-SIG-A1, [B3:B7] is "X0000" or "X1111" for SU and "0XXXX" (where X is 0 or 1) for MU. Therefore, an exemplary 8-bit signature sequence can be "00010111."

[0078] According to various embodiments, it is desirable for the bits of the signature sequence to have at least one bit that is different from the corresponding information bit in the SERVICE field of the non-HT PPDU, so as to reduce the probability of falsely detecting the non-HT PPDU as a post-HE PPDU.

[0079] According to various embodiments, a signature sequence may be provided that includes a first subset of consecutive bits in the signature sequence that is different from the corresponding subset of bits in the RL-SIG. The pattern of a second subset of consecutive bits in the signature sequence is different from the corresponding subset of bits in the VHT-SIG-A1. The pattern of a third subset of consecutive bits in the signature sequence is different from the corresponding subset of bits in the SERVICE field. Therefore, it is possible to identify the format of a post-HE PPDU without checking the value of the LENGTH field, and thus, in a post-HE PPDU, an L-SIG whose LENGTH field value is divisible by 3 can be used for another purpose.

[0080] Note that [B0:B1] in the RL-SIG, representing a rate of 6 Mbps, are "11." Furthermore, note that in VHT-SIG-A1, B2 is a reserved bit and is currently fixed at "1." Furthermore, note that in VHT-SIG-A1, [B3:B6] are "X000" or "X111" for SU and "0XXX" (where X is 0 or 1) for MU. Furthermore, note that in the SERVICE field, B7 is a reserved bit and is currently fixed at "0," and this bit becomes "1" after being scrambled with the scrambler's initial state set to "0001011" (as described below with reference to FIG. 12). Thus, an exemplary 8-bit signature sequence may be "00010110."

[0081] Figure 12 shows a scrambler 1200. The first seven bits [B0:B6] 1202 of the SERVICE field are "0001011", which also serves as the initial state of the scrambler. Because the first reserved SERVICE bit (B7) of the SERVICE field is 0 at the data input 1206, the scrambled data output 1208 provides the value "1". Therefore, the first eight bits of the SERVICE field in a non-HT PPDU are "00010111" after scrambling.

[0082] According to another example, note that in the RL-SIG representing a rate of 6 Mbps, [B0:B1] are "11", in the VHT-SIG-A1, B2 is a reserved bit and is currently fixed to 1, in the VHT-SIG-A1, [B3:B6] are "X000" or "X111" for SU and "0XXX" (where X is 0 or 1) for MU, and in the SERVICE field, [B7:B11] are reserved SERVICE bits and are currently fixed to "00000", which become "10101" after being scrambled with the scrambler's initial state set to "0001011". Thus, an exemplary 12-bit signature sequence may be "000101101010".

[0083] 13 shows another example format of an FIF 1300 according to the second embodiment. The FIF 1300 may include a Signature Sequence subfield 1302, a Format subfield 1304, and tail bits 1308. For example, when N=12 and L=6, the Signature Sequence subfield 1302 may include 12 bits, the Format subfield 1304 may include 6 bits, and the tail bits 1308 may include 6 bits. Compared to the FIF 1000 shown in FIG. 10, the FIF 1300 does not include a CRC subfield. This is because the 12-bit Signature Sequence provides sufficient error detection capability.

[0084] The following describes a process for identifying the format of a PPDU using FIF 1300, and in particular, determining whether the PHY version of the PPDU is older than a particular PHY version. Figure 14 shows a flow diagram 1400 illustrating processing at a STA or AP according to a second embodiment. A coarse identification of the PPDU format may be provided as indicated by the dotted box 1402. A fine identification of the PPDU format may be provided as indicated by the dotted box 1404. Processing may begin at 1406. At 1408, the FIF symbols may be demodulated and decoded. At 1410, it may be determined whether the CRC check passes. If it is determined that the CRC check passes, processing may continue at 1412. If it is determined that the CRC check does not pass, processing may continue at 1422. At 1412, it may be determined whether the value of the Signature Sequence field matches a known signature sequence. If it is determined that the value of the Signature Sequence field matches the known signature sequence, processing may continue at 1414. If it is determined that the value of the Signature Sequence field does not match the known signature sequence, processing may continue at 1422. At 1414, the L-SIG symbols may be demodulated and decoded. At 1416, it may be determined whether a parity check passes. If it is determined that the parity check passes, processing may continue at 1418. If it is determined that the parity check does not pass, processing may continue at 1422. At 1418, it may be determined whether the RATE field of the L-SIG is set to "1101". If it is determined that the RATE field of the L-SIG is set to "1101", processing may continue at 1420. If it is determined that the RATE field of the L-SIG is not set to "1101", processing may continue at 1422.At 1420, it may be determined whether the value of the LENGTH field of the L-SIG is evenly divisible by 3. If it is determined that the value of the LENGTH field of the L-SIG is not evenly divisible by 3, processing may continue at 1424. If it is determined that the value of the LENGTH field of the L-SIG is evenly divisible by 3, processing may continue at 1422. At 1424, the format of the received PPDU may be identified based on the value of the Format field. At 1422, processing may proceed to identifying the format of the pre-EHT PPDU. Processing may end at 1426.

[0085] FIG. 15 illustrates a configuration of a communications device 1500 (e.g., an access point (AP) or a terminal (STA; station)) according to various embodiments. Similar to the schematic example of a communications device illustrated in FIG. 4A, the communications device 1500 in the schematic example of FIG. 15 includes at least one wireless transmitter 1530, at least one wireless receiver 1504, multiple antennas 1502 (only one antenna is depicted in FIG. 18 for simplicity), and circuitry 1532. The circuitry 1532 can include at least one controller 1514, which is used to perform the tasks it is designed to perform, including controlling communications using PPDUs after HE, with the assistance of software and hardware. The circuitry 1532 can further include a receive signal processor 1506 and a transmit signal generator 1522. The controller 1514 can control the receive signal processor 1506 and the transmit signal generator 1522.

[0086] The receive signal processor 1506 may include a control signal processor 1508 and a data signal processor 1512. The control signal processor 1508 may process the control signaling portion of the received signal (e.g., FIF, SIG-A) and may include a PPDU format detector 1510. The PPDU format detector 1510 may determine the format of the received PPDU. The data signal processor 1512 may process the data portion of the received signal.

[0087] The transmit signal generator 1522 may include a control signal generator 1524, a PPDU generator 1526, and a data generator 1528. The control signal generator 1524 may generate a control signaling portion (e.g., FIF, SIG-A). The PPDU generator 1526 may generate a PPDU (e.g., PPDU after HE). The data generator 1528 may generate a data portion of the transmit signal.

[0088] As described above, the embodiments of the present disclosure provide an advanced communication system, a communication method, and a communication device that enable efficient identification of the format of a post-HE (post High Efficiency) PPDU.

[0089] The present disclosure can be implemented by software, hardware, or software operating in conjunction with hardware. Each functional block used in the above-described embodiments can be implemented, in whole or in part, by an LSI such as an integrated circuit. Each process described in each embodiment can be controlled, in whole or in part, by the same LSI or a combination of LSIs. The LSI can be formed as an individual chip, or a single chip can be formed to include some or all of the functional blocks. The LSI can include a data input / output unit coupled to it. Depending on the level of integration, the LSI can also be referred to as an IC, system LSI, super LSI, or ultra LSI. However, the technology for implementing an integrated circuit is not limited to LSI, and can be implemented using dedicated circuits, general-purpose processors, or dedicated processors. Furthermore, FPGAs (field programmable gate arrays), which can be programmed after LSI fabrication, and reconfigurable processors, which can reconfigure the connections and settings of circuit cells arranged within the LSI, can also be used. The present disclosure can be implemented using digital or analog processing. If, as a result of advances in semiconductor technology or other derivative technologies, LSI is replaced by future integrated circuit technologies, these future integrated circuit technologies can be used to integrate functional blocks. Biotechnology can also be applied.

[0090] The present disclosure can be implemented by any kind of apparatus, device, or system having a communication capability (referred to as a communication apparatus).

[0091] A communication device can include a transceiver and processing / control circuitry. The transceiver can include and / or function as a receiver and a transmitter. The transceiver (as a transmitter and receiver) can include an RF (radio frequency) module that includes an amplifier, an RF modulator / demodulator, and one or more antennas.

[0092] Some non-limiting examples of such communications devices include telephones (e.g., mobile phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (digital audio / video players), wearable devices (e.g., wearable cameras, smart watches, tracking devices), game consoles, e-readers, telehealth / telemedicine devices, vehicles (e.g., automobiles, airplanes, ships) that provide communications capabilities, and various combinations thereof.

[0093] Communication devices are not limited to portable or mobile devices, but can also include any type of equipment, device, or system that is non-portable or fixed, such as smart home devices (e.g., appliances, lights, smart meters, control panels), vending machines, and any other "thing" in an "Internet of Things" (IoT) network.

[0094] Communication can include exchanging data, for example, through cellular systems, wireless LAN systems, satellite systems, etc., and various combinations thereof.

[0095] A communications device may include devices such as a controller or a sensor coupled to the communications device to perform the communications functions described in this disclosure. For example, a communications device may include a controller or a sensor that generates control or data signals used by the communications device to perform the communications functions of the communications device.

[0096] The communications apparatus may further include infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicate with or control apparatuses such as the apparatuses in the non-limiting examples above.

[0097] Although some features of various embodiments are described with reference to devices, corresponding features also apply to the methods of various embodiments, and vice versa.

[0098] It will be appreciated by those skilled in the art that numerous changes and / or modifications may be made to the present disclosure as set forth in the specific embodiments without departing from the spirit or scope of the disclosure as broadly described, and the embodiments herein are therefore to be considered in all respects as illustrative and not restrictive.

Claims

1. a first signal field, a second signal field, a third signal field including a version-independent field and a version-dependent field, and a future signal field defined in a very high throughput signal (EHT-SIG) field or a future physical layer protocol data unit (PPDU) newer than the very high throughput physical layer protocol data unit (EHT-PPDU); the second signal field indicates that the physical layer (PHY) version of the generated PPDU is not older than a defined PHY version, the version-independent field is located at a static position from the EHT-PPDU to the future PPDU, and includes a field having a defined number of version-independent bits including a PHY version identifier that identifies the PHY version of the generated PPDU from EHT or a future PHY version newer than EHT, the defined number being plural; the third signal field is modulated with binary phase shift keying (BPSK) and is consistent from the EHT-PPDU to the future PPDU; Generate a PPDU; Integrated circuit.

2. the version-dependent bits include a variable number of bits; 10. The integrated circuit of claim 1.

3. the second signal field is a repeat of the first signal field; 10. The integrated circuit of claim 1.

4. the second signal field is mapped to tones, and each value of the second signal field in a portion of the tone is generated according to a corresponding value of the first signal field in that portion of the tone.

10. The integrated circuit of claim 1.

5. the second signal field is mapped to tones, and each value of the second signal field in a portion of the tone is generated by inverting the corresponding value of the first signal field in that portion of the tone; 10. The integrated circuit of claim 1.

6. the tones are data subcarriers; 5. The integrated circuit of claim 4.

7. The PPDU of the defined PHY version is the EHT-PPDU.

10. The integrated circuit of claim 1.

8. the second signal field and the third signal field are encoded in one orthogonal frequency division multiplexing (OFDM) symbol.

10. The integrated circuit of claim 1.

9. the first signal field and the second signal field indicate that the PHY version of the generated PPDU is not older than the defined PHY version; 10. The integrated circuit of claim 1.

Images