Patent Description:
The Institute of Electrical and Electronics Engineers (IEEE) sets standards for wireless communication technologies, including wireless local area network (WLAN) communication technologies. The IEEE <NUM> family of standards relate to WLANs and their quality of service (QoS), access point protocol, security enhancement, wireless management, etc..

There are different wireless network versions of IEEE <NUM>. The versions include <NUM>. 11a, <NUM> (Extended Rate Physical Layer (PHY), ERP), <NUM>. 11n (High Throughput, HT), <NUM>. 11ac (Very High Throughput, VHT), and <NUM>. 11ax (High Efficiency, HE). There are increasing demands on traffic caused by video streaming, cloud computing, Internet-Of-Things (IOT), big data, Augmented Reality / Virtual Reality (AR/VR), and other factors. New versions of WLAN are being developed to meet the requirements for high transmission data rates. For example, a recent Task Group called "TGbe" in IEEE <NUM> was formed to develop a next generation <NUM> WLAN standard, called IEEE <NUM>. 11be (also known as Extremely High Throughput, EHT). IEEE <NUM>. 11be has a target of maximum throughput of <NUM> Gigabits per second (Gbps) with carrier frequency operation between <NUM> and <NUM> GigaHertz (GHz) while ensuring backward compatibility and coexistence with legacy IEEE <NUM> compliant devices operating in the <NUM>, <NUM>, and <NUM> bands.

A wireless communication device is required to know which version of IEEE <NUM> is being used in a communication frame so as to properly interpret or respond to the communication frame. The device can also benefit from knowing what type of frame is being communicated. As well, the frame needs to be compatible with legacy versions along with current versions of IEEE <NUM>.

Accordingly, the object of the present invention is to provide devices, methods and computer readable media which can provide a solution for efficient, backward-compatible, low-error and robust detection of the particular WLAN PHY version of a communication to provide a communication format that indicates the type of frame being communicated. This object is solved by the attached independent claims and further embodiments and improvements of the invention are listed in the attached dependent claims. Hereinafter, up to the "brief description of the drawings", expressions like ". aspect according to the invention", "according to the invention", or "the present invention", relate to technical teaching of the broadest embodiment as claimed with the independent claims. Expressions like "implementation", "design", "optionally", "preferably", "scenario", "aspect" or similar relate to further embodiments as claimed, and expressions like "example", ". aspect according to an example", "the disclosure describes", or "the disclosure" describe technical teaching which relates to the understanding of the invention or its embodiments, which, however, is not claimed as such. Document <CIT> discloses reception of a list of Wireless LAN, WLAN, identifiers from a communication network.

For a more complete understanding of the present example embodiments, and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:.

Example embodiments relate to a control signal that enables automatic wireless LAN PHY version detection of a transmission, so that the wireless LAN PHY version can be used for interpreting the control signal and the transmission. In some example embodiments, the control signal is within a preamble of the transmission. The wireless LAN PHY version can be an IEEE <NUM> version, such as proposed IEEE <NUM>. The control signal is compatible with legacy systems and can indicate the legacy signaling information by way of a Legacy Signal (SIG) (L-SIG) field.

<FIG> provides an example schematic diagram of a wireless communication system <NUM> in which example embodiments may be implemented. The wireless communication system <NUM> includes an access point (AP, also known as an AP STA or a network coordinator) <NUM> and at least one station (STA, also known as non-AP STA) <NUM> in a wireless communication network, such as a wireless local area network (WLAN). The AP <NUM> is any entity that has STA functionality and provides access to the Internet or a distribution service for the associated STAs <NUM>. The STAs <NUM> may be mobile communication devices enabled for wireless communications, including but not limited to mobile phones, smart phones, laptops, tablet computers, machine-type communication devices, Internet of Things (IoT) devices, and wireless sensing and reporting devices. The AP <NUM> and the STAs <NUM> can each be configured to execute uplink (UL) and downlink (DL) transmissions in the WLAN.

In the WLAN, the AP <NUM> may provide access to the Internet or a distribution service for one or more STAs <NUM> that are wirelessly and communicatively associated with the AP <NUM>. The AP <NUM> can access the Internet or the distribution service by way of wired or wireless communication. Although only one single AP <NUM> is shown, this is only illustrative and is not intended to be limiting. In other examples, there may be more than one AP <NUM> within the wireless communication system <NUM>.

Referring to <FIG>, examples of the WLAN will be described in the context of wireless communications between a plurality of STAs <NUM> and an AP <NUM>. The wireless communication system <NUM> supports multi-user multiple input multiple output (MU-MIMO) transmissions, also known as a multiple access transmissions. The AP <NUM> and at least one of the STAs <NUM> may be configured for single user (SU) communications in other examples (not shown here). MU-MIMO based transmission, which can use multiple antennas, allows simultaneous channel access by the STAs <NUM> for effective use of frequency channels in the WLAN. The AP <NUM> can simultaneously transmit spatial-multiplexed data to the STAs <NUM>. Payload data can be simultaneously transmitted by the AP <NUM> to the STAs <NUM> using a plurality of respective spatial streams (stream <NUM>, <NUM>, <NUM> shown in <FIG>) in the DL direction, shown as DL MU transmissions <NUM>(<NUM>) to <NUM>(<NUM>) (generically referred to as DL MU transmission <NUM>). In the DL direction, payload data transmitted to each STA <NUM> may be different for each STA <NUM>. In the UL direction, payload data can be simultaneously transmitted to the AP <NUM> using a plurality of respective spatial streams (stream <NUM>, <NUM>, <NUM> shown in <FIG>), shown as UL MU transmissions <NUM>(<NUM>) to <NUM>(<NUM>) (generically referred to as UL MU transmission <NUM>). The DL MU transmissions <NUM> and the UL MU transmissions <NUM> are payload transmissions. The DL MU transmissions <NUM> and the UL MU transmissions <NUM> may use Orthogonal Frequency Division Multiple Access (OFDMA), with MU-MIMO or without MU-MIMO.

Reference is now made to <FIG>, which illustrates an OFDMA transmission scheme to multiplex communications with a plurality of STAs <NUM> over different frequencies (f) and times (t). The OFDMA is a multiple access scheme where different subsets of sub-carriers are allocated to different STAs <NUM>, allowing the AP <NUM> to have data communication with the different STAs <NUM> (e.g., STAs <NUM>(<NUM>) to <NUM>(<NUM>) as shown in <FIG>). The STAs <NUM> can have data transmission scheduled across both frequency (such as sub-carriers <NUM>(<NUM>) to <NUM>(n) (generically referred to as sub-carrier <NUM>) and time. As shown in <FIG>, transmission frequency channels are divided into smaller sub-channels with a predefined number of sub-carriers. A Resource Unit (RU) <NUM> includes a plurality of sub-carriers, typically with a minimum size of <NUM> sub-carriers <NUM>. The RU <NUM> has a maximum number of sub-carriers that can be used by one or more of the STAs <NUM>. The AP <NUM> can assign each STA <NUM> one or more RUs in order to perform a UL or DL transmission, or can assign multiple STAs <NUM> to a RU.

Reference is now made to <FIG> and <FIG>, wherein <FIG> illustrates a transmitter <NUM> and <FIG> illustrates a receiver <NUM>, in accordance with example embodiments. In example embodiments, the transmitter <NUM> is configured to encode the preamble and payload data of the PPDU, and then transmit the PPDU. The receiver <NUM> is configured to receive the PPDU, as applicable. In some examples, the receiver <NUM> first decodes part of the preamble of the received UL or DL PPDU in order to determine a wireless LAN PHY version of the PPDU, and then the receiver <NUM> is configured to interpret the preamble and the payload according to the determined wireless LAN PHY version. In some examples, the transmitter <NUM> and the receiver <NUM> are used to communicate trigger frames in order to solicit the UL PPDU.

The transmitter <NUM> is configured to transmit PPDU. In some examples, the transmitter <NUM> may be included within the AP <NUM> or the STA <NUM> to implement the DL or UL transmission, respectively. For example, in DL direction, the transmitter <NUM> may be included within the AP <NUM> to transmit PPDU containing a preamble and respective payload data to STAs <NUM> on their respective sub-carriers in one or more RUs. In UL direction, the transmitter <NUM> may be included within an associated STA <NUM> to transmit preamble and payload data of the STA <NUM> on its respective sub-carriers in one or more RUs.

As shown in <FIG>, the transmitter <NUM> includes a plurality of transmitting (Tx) paths <NUM>(<NUM>) to <NUM>(Z) (generically referred to as Tx path <NUM>) for a transmission that includes a preamble and payload data. When the transmitter <NUM> is in the AP <NUM>, for DL transmission, the AP <NUM> can generate Tx paths <NUM> for different respective STAs (e.g., STA <NUM> to STA Z).

One Tx path <NUM> for one STA <NUM> will now be described in detail. A series of bits are received by the symbol modulator <NUM> in the Tx path <NUM>. The symbol modulator <NUM> performs symbol modulation on the bits of the payload data to data symbols (also known as a constellation symbols). The data symbols can be represented as amplitude and phase, or cosine and sine coefficients, or other nomenclatures, as is understood in the art. Each data symbol may be referred to as a chip. The symbol modulation can be based on symbol modulation schemes such as amplitude-shift keying (ASK), phase-shift keying (PSK), binary PSK (BPSK), quadrature PSK (QPSK), quadrature amplitude modulation (QAM), or any other appropriate method of mapping series of data bits to a modulated symbol. The QAM constellations can be specified by cosine and sine coefficients in quadrature.

The tone mapping block <NUM> maps or assigns each data symbol to one or more of the sub-carriers, known as tone mapping. The data symbols are provided to the Inverse Fast Fourier Transform (IFFT) block <NUM> to transform the data symbols to the assigned sub-carriers in time domain. Other types of inverse Fourier transforms can be performed in other examples. The output from the IFFT block <NUM> are OFDMA waveforms in time domain, in parallel for each STA. The cyclic prefix generator <NUM> adds a cyclic prefix to the OFDMA waveforms. The parallel to serial converter (P/S) <NUM> converts the parallel OFDMA waveforms of multiple STAs into a serial digital signal. The serial digital signal is converted by a digital-to-analog converter <NUM> to an analog signal, which is transmitted via an antenna <NUM>. The transmission that is transmitted via the antenna <NUM> can include the preamble (which can have one or more coded/modulated fields as described in greater detail herein) and the coded/modulated data.

Reference is now made to <FIG>, which illustrates a receiver <NUM> for demodulating each received OFDMA signal in accordance with an example embodiment. In some examples, the receiver <NUM> may be included within each STA <NUM> to decode the received OFDMA signal from the DL transmission of the AP <NUM>. In some examples, the receiver <NUM> may be included within the AP <NUM> to decode received OFDMA signals from the UL transmission of the STAs <NUM>. As illustrated in <FIG>, the receiver <NUM> includes an antenna <NUM>, an analog-to digital converter (ADC) <NUM>, a cyclic prefix removal block <NUM>, a fast fourier transform (FFT) block <NUM>, and rea plurality of receiving (Rx) paths <NUM>(<NUM>) to <NUM>(Z) (generically referred to as Rx path <NUM>) on which data is received and the desired data is recovered. For DL transmission, only one receiving path corresponding to one STA <NUM> needs to be processed by the receiver <NUM> of the corresponding STA <NUM>. For UL transmission, all of the receiving paths, corresponding to all STAs <NUM>, can be processed by the receiver <NUM> of the AP <NUM>.

The antenna <NUM> of the receiver <NUM> receives analog signals from wireless communication frequency channels, such as from the transmitter <NUM> as shown in <FIG>. The ADC <NUM> converts each received analog signal into a digital signal. The cyclic prefix removal block <NUM> removes a cyclic prefix from the digital signal. The FFT block <NUM> then transforms the cyclic prefix removed digital signal in time domain into data symbols. The data symbols for each STA <NUM> from the FFT block <NUM> are processed on a respective one of the plurality of Rx paths. For clarity, one Rx path <NUM>(<NUM>) is indicated by a dashed box. One Rx path <NUM> will now be described in detail. Data symbols are provided to a channel equalizer <NUM> for equalization, which may help to reduce inter-symbol interference (ISI) and noise effects for better demodulation. The equalized data symbols from the channel equalizer <NUM> are input to the symbol demodulator <NUM>. The symbol demodulator <NUM> uses symbol demodulation to demodulate the data symbols into series of bits for the STA <NUM> to recover the data. The receiver <NUM> can receive and interpret the preamble of the received signals. When the preamble has one or more coded or modulated fields (as described in greater detail herein), the receiver <NUM> can be used to decode or demodulate the preamble.

In UL direction, a transmission including a preamble and payload data is transmitted from each associated STA <NUM> to the AP <NUM>, in response to the STA <NUM> receiving a trigger frame. The trigger frame can include resource allocation information of one or more RUs for the payload data of each associated STA <NUM>. In some examples, at least one of the fields of the trigger frame is coded by the transmitter <NUM>. After each STA <NUM> receives the trigger frame, the STA <NUM> (having the transmitter <NUM>) can transmit a PPDU containing a preamble and payload data of the STA <NUM> over one or more sub-carriers using the received resource allocation information, and modulate the data symbols over the one or more sub-carriers of the one or more RUs. The AP <NUM> (having the receiver <NUM>) can receive and interpret the transmission from the STAs, which include a preamble and OFDMA signals of the payload data. When the preamble has one or more coded fields (as described in greater detail herein), the receiver <NUM> can be used to decode the preamble.

Referring to <FIG>, in some examples the transmitter <NUM> includes a Cyclic Shifter <NUM>, which can be used to perform cyclic shifting, in time domain, on at least part of the preamble or the data payload. The cyclic shifting can be performed after the IFFT block <NUM> and prior to the Cyclic Prefix Generator <NUM>. Similarly, the receiver <NUM> can include a Cyclic Shifter <NUM> for reversing, in time domain and prior to the FFT <NUM>, the cyclic shifting that was performed by the Cyclic Shifter <NUM> of the transmitter <NUM>. In other example embodiments, there is no Cyclic Shifter <NUM> or Cyclic Shifter <NUM>.

In some examples, shown in <FIG>, the transmitter <NUM> includes a coding block <NUM> for coding the data bits, to generate coded data bits that are then input to the symbol modulator <NUM>. Examples of the coding block <NUM> include block convolutional code (BCC) coding, repeat coding, interleaving, or scrambling. In some examples, shown in <FIG>, the receiver <NUM> includes a decoding block <NUM> for decoding any coded data bits after the symbol de-modulator block <NUM>, to generate the original data bits. The decoding block <NUM> can include BCC decoding, repeat decoding, deinterleaving, or descrambling. In other example embodiments, there is no coding block <NUM> or decoding block <NUM>.

Example embodiments relate to a control signal that enables automatic wireless LAN PHY version detection of a transmission, so that the wireless LAN PHY version can be used for interpreting signaling information of the transmission and decoding of the payload of the transmission. In some example embodiments, the control signal is within a preamble of the transmission. The wireless LAN PHY version can be an IEEE <NUM> version, such as proposed IEEE <NUM>. The control signal is compatible with legacy systems and can indicate the legacy signaling information by way of a Legacy Signal (SIG) (L-SIG) field.

Some examples of legacy signaling from earlier versions of IEEE <NUM> will now be described in greater detail. The legacy signaling can be included into the control signal (e.g., the preamble) of example embodiments, so as to be backwards compatible.

<FIG> illustrates an Orthogonal Frequency-Division Multiplexing (OFDM) Physical Layer Convergence Procedure (PLCP) Protocol Data Unit (PPDU) <NUM> according to IEEE <NUM>. Information specified in each field is in the frequency domain. In IEEE <NUM>. 11a/g, OFDM modulation is applied to the desired signal over the sub-carrier signals by taking a <NUM>-point IFFT over <NUM> bandwidth (sub-carrier spacing <NUM>) to generate one OFDM symbol in the time domain with a guard interval added as a cyclic prefix. The duration of each OFDM symbol is <NUM> microseconds (µs).

The PPDU <NUM> in <FIG> includes a Preamble <NUM> and a Data field <NUM>. The Data field <NUM> is the payload data. The Preamble <NUM> includes Short Training field (STF) <NUM>, Long Training field (LTF) <NUM>, and Signaling (SIG) field <NUM>, all of which are defined by the IEEE <NUM>. 11a PPDU format.

The STF <NUM> is for signal detection, Automatic Gain Control (AGC), discovery selection, coarse frequency offset estimation, and timing synchronization. The STF <NUM> includes two OFDM symbols.

The LTF <NUM> is for more accurate timing synchronization, more accurate estimate of frequency offset, and frequency channel estimation. The LTF <NUM> includes two OFDM symbols.

The SIG field <NUM> is an indication of the length and transmission rate of the PHY service data unit (PSDU). The SIG field <NUM> is coded with code rate <NUM>/<NUM> block convolutional code (BCC) and is modulated using BPSK modulation. One OFDM symbol is used for transmission of the SIG field <NUM>.

<FIG> illustrates the SIG field <NUM> of the OFDM PPDU <NUM> of <FIG> according to IEEE <NUM>. As shown in <FIG>, the SIG field <NUM> includes total <NUM> bits, as follows (bit positions are denoted with "b").

Rate subfield <NUM> (b0-b3) represents transmission rate in the <NUM> bandwidth.

Reserved subfield <NUM> (b4) is reserved. It shall be set to <NUM> on transmit and ignored on receive.

Length subfield <NUM> (b5-b16) is a <NUM>-bit integer that indicates the PSDU length in octets.

Parity subfield <NUM> (b17) is a positive parity (even parity) bit for bits <NUM>-<NUM>.

Tail subfield <NUM> (b18-b23) refers to tail bits, set to all zeros, to terminate the state of the BCC and used for the SIG field <NUM> encoding.

<FIG> illustrates a method <NUM> of encoding the SIG field <NUM> of <FIG> according to IEEE <NUM>. The method <NUM> can be performed by the transmitter <NUM>. The SIG field <NUM> has <NUM> bits. At step <NUM>, the transmitter <NUM> encodes the SIG field <NUM> with code rate <NUM>/<NUM> block convolutional code (BCC), to a coded SIG of <NUM> bits. At step <NUM>, the symbol modulator <NUM> of the transmitter <NUM> modulates the coded SIG using BPSK modulation to <NUM> data sub-carriers. At step <NUM>, the tone mapping block <NUM> of the transmitter <NUM> performs tone mapping of the BPSK modulated SIG over <NUM> sub-carriers. At step <NUM>, the IFFT block <NUM> of the transmitter <NUM> then applies OFDM modulation over the <NUM> sub-carrier signals in accordance with the tone mapping, by taking a <NUM>-point IFFT, arriving at a SIG symbol.

The detection of the IEEE <NUM>. 11a/g PPDU <NUM> includes detecting transmitted signal strength in the Preamble <NUM> and a check on the single bit of the Parity subfield <NUM> in the SIG field <NUM>. The Rate subfield <NUM> in the SIG field <NUM> can be used differentiate between an IEEE <NUM> PPDU and an IEEE <NUM>.

Continuing through the IEEE <NUM> standard versions, other example indicators for automatic detection of wireless network type are defined by IEEE <NUM>. 11n (HT-mixed) and IEEE <NUM>. 11ac (VHT), not shown here.

For IEEE <NUM>. 11ax, <FIG> illustrates an OFDM High Efficiency (HE) PPDU <NUM> according to IEEE <NUM>. The prefix "L" indicates Legacy. The L-STF subfield <NUM> and L-LTF subfield <NUM> are the same as defined by IEEE <NUM>. 11a in the legacy OFDM PPDU <NUM> (<FIG>). The PPDU <NUM> also includes a L-SIG field <NUM>, a Repeated L-SIG field <NUM>, HE Signaling fields <NUM>, Data <NUM>, and Packet Extension (PE) <NUM>.

The L-SIG field <NUM> follows the same format as the SIG field <NUM> shown in <FIG>, the Rate subfield <NUM> is set to <NUM> Mb/s (i.e., bit positions b0b1b2b3 = "<NUM>" to represent <NUM> Mb/s); the Length subfield <NUM> is set to be a value which is not divisible by <NUM>; the Reserved subfield <NUM> is set to <NUM>; the Parity subfield <NUM> is set to even parity of bits <NUM>-<NUM> and the Tail subfield <NUM> is set to <NUM>.

The RL-SIG field <NUM> in the PPDU <NUM> is a repeat of the L-SIG field <NUM> and is used in IEEE <NUM>. 11ax to distinguish the HE PPDU <NUM> from a non-HT PPDU, HT PPDU and VHT PPDU.

In IEEE <NUM>. 11ax, automatic detection of the wireless LAN PHY version of the HE PPDU <NUM> is performed based on at least detection of repetition between L-SIG symbol carrying L-SIG field <NUM> and RL-SIG symbol carrying RL-SIG field <NUM> and decoding of Rate subfield <NUM> and Length subfield <NUM> information in L-SIG field <NUM>. The procedure for automatic detection of HE PPDU <NUM> for an HE receiver (e.g., using receiver <NUM>) is as follows:.

Having described some existing IEEE standards for automatic detection of the wireless LAN PHY version, example embodiments for automatic detection of a wireless LAN PHY version will now be described. Example embodiments include the generating of a control signal, such as the preamble or the trigger frame, for a transmission. In some examples, the preamble is an EHT preamble of proposed IEEE <NUM>. The automatic detection of wireless LAN PHY version type of the PPDU can be achieved with an identifier, which can be an identifier symbol, an identifier field or subfield, or other types of identifiers. The identifier symbol can be defined by the identifier field or subfield, or by the encoding or modulation performed on the identifier field or subfield to arrive at the identifier symbol. In some examples, an identifier symbol is generated from at least part of, but is not identical to, the L-SIG symbol. In other examples, an identifier field or subfield is separate from the L-SIG field and the RL-SIG field.

<FIG> illustrates an example of an OFDM PPDU <NUM> having auto-detectable wireless LAN PHY version indication, in accordance with an example embodiment. The PPDU <NUM> includes an identifier field which is different than the RL-SIG, denoted Partial Repeated Legacy Signal (SIG) (PRL-SIG) field <NUM>. The L-STF subfield <NUM> and L-LTF subfield <NUM> are the same as defined by IEEE <NUM>. 11a in the legacy OFDM PPDU <NUM> (<FIG>). The PPDU <NUM> can include a SIG field particular to signaling information of the indicated wireless LAN PHY version, such as EHT-SIG in this example. The EHT-SIG and the payload data are collectively referred to as EHT-SIG and Data <NUM>.

In IEEE <NUM>. 11ax, RL-SIG is a fully repeated version of L-SIG <NUM> including Rate (which is set to "<NUM>" to indicate a fixed code rate of <NUM> Mbps), Parity and Length which are used jointly for automatic detection IEEE <NUM>. The Length is also used for calculation of the number of OFDM symbols in the data transmission in the PPDU. <FIG> illustrates, instead of the RL-SIG field of IEEE <NUM>. 11ax, a different indicator denoted partial RL-SIG (PRL-SIG) field <NUM>.

In the example PPDU <NUM> of <FIG>, using the same definition as in IEEE <NUM>. 11ax, the Rate in the L-SIG is also set to "<NUM>" to indicate a fixed code rate of <NUM> Mbps. In IEEE <NUM>. 11ax, a single Parity bit in the SIG may be used for error detection, but can cause an error detection problem in lower signal-to-noise (SNR) conditions. The Rate subfield is set to a known value in the L-SIG in IEEE <NUM>. 11ax, and is known by the receiver <NUM> to be <NUM> Mbps once the wireless LAN PHY version is known.

In the PPDU <NUM>, at least Cyclic Redundancy Check (CRC) is used for the error detection. In the PRL-SIG field <NUM>, the CRC is at the same corresponding subfield location (bit positions) as the Rate subfield defined in L-SIG <NUM>. The bits in the remaining subfields defined in L-SIG <NUM> are repeated or partially repeated in the PRL-SIG field <NUM>. In some examples, some bits of the remaining subfields defined in L-SIG <NUM> are different in the PRL-SIG field <NUM>.

In an example embodiment, automatic detection of the PPDU <NUM> of <FIG> is conducted based on a CRC check, or in other examples, a combination of the CRC check plus a Parity check. In some examples, the PRL-SIG field <NUM> of <FIG> is modulated by the symbol modulator <NUM> using BPSK modulation. Automatic detection can further be conducted by recognition of the PRL-SIG field <NUM> as being modulated using BPSK modulation.

<FIG> illustrates an example embodiment of the PRL-SIG field <NUM>, introduced in <FIG> as PRL-SIG field <NUM>. The PRL-SIG field <NUM> is an identifier field for automatic detection of the wireless LAN PHY version. In the PRL-SIG field <NUM> of <FIG>, the subfields include the CRC subfield <NUM>, Reserved (R) subfield <NUM>, Length subfield <NUM>, Parity (P) subfield <NUM>, and Tail subfield <NUM>. In this example embodiment of the PRL-SIG field <NUM>, the <NUM> CRC bits and <NUM> Tail bits can be coded together using a code rate <NUM>/<NUM> BCC encoder, which is the same type of BCC encoder as used for L-SIG <NUM>. The CRC in the CRC subfield <NUM> protects the Rate (i.e., bit positions b0-b3) and Length (i.e., b5-b16) in the L-SIG <NUM>.

<FIG> illustrates an example method <NUM> of encoding the PRL-SIG field <NUM> of <FIG>. In an example embodiment, the method <NUM> can be performed by the transmitter <NUM> (<FIG>). At step <NUM>, the transmitter <NUM> performs segment parsing of the PRL-SIG field <NUM> to a first group of bits and a second group of bits. The first group of bits is the CRC subfield <NUM> and Tail subfield <NUM>, and the second group of bits is the Reserved (R) subfield <NUM>, Length subfield <NUM>, and Parity (P) subfield <NUM>. At step <NUM>, the transmitter <NUM> encodes the CRC and Tail using a code rate <NUM>/<NUM> BCC encoder. At step <NUM>, the transmitter <NUM> duplicates the coded Reserved, Length, and Parity bits generated in L-SIG. At step <NUM>, the transmitter <NUM> constructs together the coded bits from the first group of bits and the second group of bits and sends the constructed coded bits to the symbol modulator <NUM> (<FIG>) for BPSK modulation.

<FIG> illustrates an example method <NUM> of detection of the PRL-SIG field <NUM> from the signal generated by the method <NUM> of <FIG>. At the receiver <NUM>, a signal (PPDU) in time domain is received and the FFT block <NUM> of the receiver <NUM> performs Fast Fourier Transform to recover coded bits of the PRL-SIG field <NUM>. At step <NUM>, the receiver <NUM> detects the repetition of Reserved (R) subfield <NUM>, Length subfield <NUM>, and Parity (P) subfield <NUM> from the PRL-SIG field <NUM>, by comparing with the corresponding coded bits in L-SIG. At step <NUM>, the receiver <NUM> performs segment parsing of the received coded PRL-SIG to a first group of bits and a second group of bits. The first group of bits is the coded CRC subfield <NUM> and Tail subfield <NUM> and the second group of bits is the coded Reserved subfield <NUM>, Length subfield <NUM>, and Parity subfield <NUM>. At step <NUM>, the receiver <NUM> performs code rate <NUM>/<NUM> BCC decoding on the first group of bits to generate the decoded bits of the CRC. At step <NUM>, the receiver <NUM> combines the second group of bits with coded L-SIG subfields Rate, Reserved, Length, Parity, and Tail, the combination of which at step <NUM> is decoded using code rate <NUM>/<NUM> BCC decoding to generate the decoded bits of Rate, Length and Parity.

In an example, the receiver <NUM> can conduct a CRC check, using the decoded bits of CRC, onto the protected Rate and Length subfields (decoded from the L-SIG and the PRL-SIG). If the CRC check passes, the receiver determines the PPDU to be a specified wireless LAN PHY version, such as IEEE <NUM>. In other examples, the check is a combination of a CRC check, and a Parity check with the L-SIG.

<FIG> illustrates another example method <NUM> of encoding the PRL-SIG field <NUM> of <FIG>. The format of the PRL-SIG field <NUM> in this example is the same as shown in <FIG>. However, in the method <NUM> of <FIG>, the encoding for the CRC is different than in <FIG>. In the method <NUM>, the CRC bits are coded by coding block <NUM> with a code rate <NUM>/<NUM> tail biting BCC encoder. The tail biting BCC encoder does not use the tail bits of the Tail subfield <NUM> (<FIG>). The CRC protects the Rate (i.e., bit positions b0-b3) and Length (i.e., b5-b16) of the L-SIG.

In the method <NUM> of <FIG>, at step <NUM> the transmitter <NUM> performs segment parsing of the PRL-SIG field <NUM> to a first group of bits and a second group of bits. The first group of bits is the CRC subfield <NUM>, and the second group of bits is the Reserved subfield <NUM>, Length subfield <NUM>, Parity subfield <NUM>, and Tail subfield <NUM>. At step <NUM>, the transmitter <NUM> encodes the CRC with the tail biting BCC encoder, which does not use the Tail bits. At step <NUM>, the transmitter <NUM> duplicates the coded Reserved, Length, Parity, and Tail generated in L-SIG. At step <NUM>, the transmitter <NUM> constructs together the coded bits from the first group of bits and the second group of bits and sends the constructed <NUM> coded bits to the symbol modulator <NUM> (<FIG>) for BPSK modulation.

<FIG> illustrates an example method <NUM> of detecting the coded PRL-SIG field <NUM> from the signal generated by the method <NUM> of <FIG>. Generally, the receiver <NUM> can perform detection of the CRC in the PRL-SIG field <NUM> and the Length and Parity in both the L-SIG and PRL-SIG. At the receiver <NUM>, a signal (PPDU) in time domain is received and the FFT block <NUM> of the receiver <NUM> performs Fast Fourier Transform to recover coded bits of the PRL-SIG field <NUM>. At step <NUM>, the receiver <NUM> detects the repetition of Reserved, Length, Parity and Tail in the coded bits of the PRL-SIG field <NUM>. At step <NUM>, the receiver <NUM> performs segment parsing of the received coded PRL-SIG field <NUM> to a first group of bits and a second group of bits. The first group of bits is the coded CRC subfield <NUM> and a second group of bits is the coded Reserved, Length, Parity and Tail. At step <NUM>, the receiver <NUM> performs code rate <NUM>/<NUM> tail biting BCC decoding on the first group of bits to generate the decoded bits of the CRC. At step <NUM>, the receiver <NUM> combines the second group of bits with coded L-SIG subfields Rate, Reserved, Length, Parity, and Tail, the combination of which at step <NUM> is decoded using code rate <NUM>/<NUM> BCC decoding to generate the decoded bits of Rate, Length and Parity.

In an example, the receiver <NUM> can conduct a CRC check onto the protected Rate and Length subfields (from the L-SIG and/or the PRL-SIG). If the CRC check passes, the receiver <NUM> determines the PPDU to be a specified wireless LAN PHY version, such as IEEE <NUM>. In other examples, the check is a combination of the CRC check, and a Parity check with the L-SIG.

<FIG> illustrates a second example embodiment of the PRL-SIG field <NUM>, introduced in <FIG> as PRL-SIG field <NUM>, and includes the Cyclic Redundancy Check (CRC). The PRL-SIG field <NUM> is an identifier field for automatic detection of the wireless LAN PHY version. In this example, the subfields in the PRL-SIG field <NUM> include a <NUM>-bit CRC subfield <NUM> which protects the Length subfield, i.e., bit positions b5-b16 in L-SIG. The PRL-SIG field <NUM> also includes a CRC Repeat subfield <NUM>. In the CRC Repeat subfield <NUM>, the CRC bits from CRC subfield <NUM> repeat twice and the repeated CRC bits are located in bit positions b18-b23. The CRC protects the Rate subfield (i.e., b0-b3) and Length subfield (i.e., b5-b16) in L-SIG. In other examples, rather than repeating twice, the CRC bits in CRC Repeat subfield <NUM> repeat once or repeat more than twice.

<FIG> illustrates an example method <NUM> of encoding the PRL-SIG field <NUM> of <FIG>. In an example embodiment, the method <NUM> can be performed by the transmitter <NUM> (<FIG>). At step <NUM>, the transmitter <NUM> performs segment parsing of the PRL-SIG field <NUM> to a first group of bits and a second group of bits. The first group is the CRC subfield <NUM> and CRC Repeat subfield <NUM>, and the second group of bits is the Rate subfield (<NUM> bit at b3), Reserved subfield, Length subfield, and Parity subfield. At step <NUM>, the transmitter <NUM> encodes the first group of bits containing the CRC using 2x repetition coding. At step <NUM>, the transmitter <NUM> duplicates the coded Rate (<NUM> bit), Reserved, Length, and Parity generated in L-SIG bits. At step <NUM>, the transmitter <NUM> constructs together the coded bits from the first group of bits and the second group of bits and sends the constructed <NUM> coded bits to the symbol modulator <NUM> (<FIG>) for BPSK modulation.

<FIG> illustrates an example method <NUM> of receiving and detecting the coded PRL-SIG field <NUM> from the signal generated by the method <NUM> of <FIG>. The receiver <NUM> can perform detection of the CRC in the PRL-SIG field <NUM>, and perform detection of the Length and Parity in both L-SIG and PRL-SIG.

At the receiver <NUM>, a signal (PPDU) in time domain is received and the FFT block <NUM> of the receiver <NUM> performs Fast Fourier Transform to recover coded bits of the PRL-SIG field <NUM>. At step <NUM>, the receiver <NUM> detects repetition of the Reserved, Length, and Parity in the coded bits of the PRL-SIG field <NUM>. At step <NUM>, the receiver <NUM> performs segment parsing of the received coded PRL-SIG field <NUM> to a first group of bits and a second group of bits. The first group of bits is the repetition coded CRC (which were originally coded from the CRC subfield <NUM> and CRC Repeat subfield <NUM> of the PRL-SIG <NUM>). The second group of bits is the coded Rate (<NUM> bit) subfield, Reserved subfield, Length subfield, Parity subfield, which were originally coded from the PRL-SIG <NUM>. At step <NUM>, the receiver <NUM> performs repetition decoding on the first group of bits to generate the decoded bits of the CRC. At step <NUM>, the receiver <NUM> combines the second group of bits with coded L-SIG subfields Rate, Reserved, Length, Parity, and Tail, the combination of which at step <NUM> is decoded using code rate <NUM>/<NUM> BCC decoding to generate the decoded bits of Rate, Length and Parity.

After detection and decoding of CRC, Rate, Length, and Parity subfields as shown in <FIG>, <FIG> and <FIG>, the receiver <NUM> can conduct a CRC check (or combination of CRC check and Parity check) onto the protected Rate and Length subfields (from PRL-SIG and L-SIG). If the CRC check (or combination of CRC check and Parity check) passes, the receiver determines the PPDU to be a specified wireless LAN PHY version, such as IEEE <NUM>. Otherwise, the receiver <NUM> can further detect whether the PPDU is an IEEE <NUM>. 11ax PPDU, or other PPDU types.

<FIG> illustrates another example embodiment of the PRL-SIG field <NUM>, introduced in <FIG> as PRL-SIG field <NUM>, in which the PRL-SIG field <NUM> has a Flag subfield <NUM>. The PRL-SIG field <NUM> is an identifier field for automatic detection of the wireless LAN PHY version. The PRL-SIG field <NUM> includes a Reserved subfield <NUM>, a Length subfield <NUM>, a Parity subfield <NUM>, and a Tail subfield <NUM>. As defined in IEEE <NUM>. 11ax and proposed IEEE <NUM>. 11be, the Rate in the L-SIG is set to "<NUM>" to indicate a fixed rate of <NUM> Mbps. An example embodiment of the PPDU <NUM> includes the partial RL-SIG (PRL-SIG) field <NUM> which is subsequent to the L-SIG. Because the Rate subfield of the L-SIG is set to a known value in the L-SIG, the Rate does not need to be verified by the receiver <NUM>. Therefore, in the PRL-SIG field <NUM>, the Rate subfield defined in L-SIG can be (at least partially) different than the PRL-SIG field <NUM>, with a Flag subfield <NUM> at the same corresponding subfield location (corresponding bit positions). The remaining bits in the remaining subfields defined in L-SIG can be repeated in the PRL-SIG field <NUM> in an example. The Flag <NUM> is set to a predefined value which is different from "<NUM>" to indicate the specified wireless LAN PHY version of the PPDU, such as IEEE <NUM>. 11be or future amendments. Various different flags can each represent a different wireless LAN PHY version in some examples.

The PRL-SIG field <NUM> of <FIG> includes a Flag subfield <NUM> of <NUM> bits and Tail subfield <NUM> of <NUM> bits. For encoding of the PRL-SIG field <NUM> of <FIG>, the Flag subfield <NUM> and the Tail subfield <NUM> are coded together by the coding block <NUM> using a code rate <NUM>/<NUM> BCC encoder (e.g., the same type of BCC encoder as used for L-SIG). The generation of the coded PRL-SIG <NUM> from <FIG> is similar to the method <NUM> of generating the coded PRL-SIG as illustrated in <FIG>, by replacing "CRC" with "Flag".

At the receiver <NUM>, detection and interpreting Flag subfield <NUM> in the PRL-SIG field <NUM> and the Length and Parity in both L-SIG field and PRL-SIG field <NUM> are similar to the method <NUM> of detecting and interpreting of the coded PRL-SIG as shown in <FIG>, by replacing "CRC" with "Flag".

Another example format of the PRL-SIG will now be described, not shown. The format of the PRL-SIG in this example is the same as the PRL-SIG <NUM> as shown in <FIG>. In the example PRL-SIG, the encoding for the Flag is different than the PRL-SIG field <NUM>. The bits of the Flag subfield <NUM> are coded with a code rate <NUM>/<NUM> tail biting BCC encoder. A tail biting convolutional code does not require tail bits for termination. Generation of the coded PRL-SIG is similar to the method <NUM> for generation of the coded PRL-SIG <NUM> as illustrated in <FIG>, by replacing "CRC" with "Flag". At the receiver <NUM>, detection and interpreting of Flag in the example PRL-SIG and the Length and Parity in both L-SIG and PRL-SIG are similar to the method <NUM> of receiving and interpreting the PRL-SIG <NUM> as illustrated in <FIG>, by replacing "CRC" with "Flag".

<FIG> illustrates another example embodiment of the PRL-SIG field <NUM>, introduced in <FIG> as PRL-SIG field <NUM>. The PRL-SIG field <NUM> is an identifier field for automatic detection of the wireless LAN PHY version. The PRL-SIG field <NUM> includes a Flag subfield <NUM>, Repeated Rate subfield <NUM>, Reserved subfield <NUM>, Length subfield <NUM>, Parity subfield <NUM>, and Flag Repeat subfield <NUM>. The subfields in the PRL-SIG field <NUM> include a <NUM>-bit Flag subfield <NUM>, which is repeated twice and the repeated bits are located into the Flag Repeat subfield <NUM> (bit positions b18-b23) of the PRL-SIG field <NUM>. In other examples, the Flag subfield <NUM> is repeated once, or more than twice, in the Flag Repeat subfield <NUM>.

The method of generation of coded PRL-SIG <NUM> from <FIG> is similar to the method <NUM> of generating the coded PRL-SIG <NUM> as illustrated in <FIG>, by replacing "CRC" with "Flag".

At the receiver <NUM>, detection and interpreting of Flag subfield <NUM> in PRL-SIG field <NUM> and the Length and Parity in both L-SIG and PRL-SIG field <NUM> are similar to the method <NUM> of receiving and interpreting as shown in <FIG>, by replacing "CRC" with "Flag".

After detection and decoding of Flag, Rate, Length, and Parity subfields as stated above, similar to a HE receiver, the receiver <NUM> can check whether Rate, Length and Parity are valid by comparing to L-SIG as defined in IEEE <NUM>. If Rate, Length and Parity are valid, the receiver <NUM> further checks Flag. If Flag is valid, the receiver <NUM> determines the PPDU is a specified wireless LAN PHY version such as IEEE <NUM>. Otherwise the PPDU is the HE PPDU. If Rate, Length or Parity is not valid, the receiver <NUM> can detect other legacy PPDU types.

Reference is now made to <FIG>, <FIG>. In <FIG>, in an example embodiment, the auto-detection of the wireless LAN PHY version of the PPDU can be provided by an Identifier <NUM>. <FIG> illustrate various example embodiments of an OFDM PPDU having the Identifier <NUM>, for indicating both the Physical Layer (PHY) version and the frame-type of the OFDM PPDU.

The Identifier <NUM> can be a field or a subfield of the PPDU, and is contained within the PHY header (preamble). The Identifier <NUM> has a PHY Version Identifier <NUM>. The PHY Version Identifier <NUM> can be used to indicate the wireless LAN PHY version, e.g. IEEE <NUM> version or an amendment version. This allows for extensibility of the auto-detection method for IEEE <NUM>. 11be and future versions or standards. The Identifier <NUM> also indicates the frame format type, referred to herein as a Frame Type Identifier <NUM>. The Frame Type Identifier <NUM> can identify frame types such as MU, SU, TB or ER SU PPDU. The Frame Type Identifier <NUM> can be used to identify any other possible frame type and future frame types.

In various examples, the Identifier <NUM> is greater than <NUM> bits, greater than <NUM> bits, equal to <NUM> bits, or equal to <NUM> bits. In an example, <NUM> to <NUM> bits are used for the PHY Version Identifier <NUM>, and <NUM> to <NUM> bits are used for the Frame Type Identifier <NUM> (totaling <NUM> bits in each case). <FIG> show example locations of the Identifier <NUM> in a PPDU.

The number of symbols for the Identifier <NUM> can be one symbol in an example, or more than one symbol in other examples. In an example embodiment, the Identifier <NUM> can be subsequent to the RL-SIG or L-SIG. In another example, the Identifier <NUM> can be within the SIG field particular to signaling information of the indicated wireless LAN PHY version, such as an EHT-SIG field as a subfield type.

<FIG> illustrates a first example embodiment of the OFDM PPDU <NUM>, wherein the Identifier <NUM> is a field that is separate from, and subsequent to, the L-SIG and RL-SIG. In some examples, the Identifier <NUM> is transmitted after the L-SIG and the RL-SIG.

<FIG> illustrates a second example embodiment of the OFDM PPDU <NUM>, wherein the Identifier <NUM> is a field that is subsequent to L-SIG, and there is no RL-SIG in this example OFDM PPDU <NUM>. In some examples, the Identifier <NUM> is transmitted after the L-SIG.

<FIG> illustrates a third example embodiment of the OFDM PPDU <NUM>, wherein the Identifier <NUM> is a subfield within a SIG field particular to signaling information of the indicated wireless LAN PHY version, such as EHT-SIG <NUM> in this example. In the OFDM PPDU <NUM>, the Identifier <NUM> is a subfield within EHT-SIG <NUM>, and EHT-SIG <NUM> is separate from, and subsequent to, L-SIG and RL-SIG. In some examples, the Identifier <NUM> subfield is transmitted after the L-SIG and the RL-SIG.

In the OFDM PPDU <NUM> of <FIG>, the Identifier <NUM> is a subfield within the EHT-SIG <NUM>, and EHT-SIG <NUM> is subsequent to L-SIG. There is no RL-SIG in the example PPDU <NUM> of <FIG>. In some examples, the Identifier <NUM> subfield is transmitted after the L-SIG.

As shown in <FIG>, in an example embodiment, the Identifier <NUM> includes the PHY Version <NUM> as a separate subfield (separate bits) from the Frame Type Identifier <NUM>. The Identifier <NUM> includes a first set of one or more bits that represent the PHY Version Identifier <NUM> of the transmission and a second set of one or more bits that represent the Frame Type Identifier <NUM> of the transmission. In another example, not shown here, the Identifier <NUM> includes at least some shared bits that represent both the wireless LAN PHY version of the transmission and the Frame Type Identifier <NUM> of the transmission. In other words, a predefined coding scheme, lookup table, specified policy, algorithm, etc., can be used to translate the bits of the Identifier <NUM> to each of the PHY Version Identifier <NUM> and the Frame Type Identifier <NUM>.

In an example, not shown here, the Identifier <NUM> can be within a trigger frame to solicit uplink transmission. In an example, not shown here, the Identifier <NUM> can be within a preamble of the uplink transmission, having a field or subfield position similar to any one of the OFDM PPDU <NUM>, <NUM>, <NUM>, <NUM>.

<FIG> illustrates an example embodiment of an OFDM PPDU <NUM> having auto-detectable wireless LAN PHY version indication using a different version of the RL-SIG, by way of an Interleaved RL-SIG (IRL-SIG) field <NUM>. The IRL-SIG field <NUM> is an identifier field for automatic detection the wireless LAN PHY version. The OFDM PPDU <NUM> includes the same L-STF, L-LTF and L-SIG fields that are defined by legacy standards. The OFDM PPDU <NUM> can include one or more SIG fields particular to signaling information of the indicated wireless LAN PHY version, such as EHT Signaling Fields <NUM> in this example. In the example OFDM PPDU <NUM>, a different version of the L-SIG in the coded bit level is the IRL-SIG field <NUM>, in which an interleaved version of the coded bits from the L-SIG is generated by re-arranging the order of bits from the L-SIG using a specified interleaver known by both the transmitter <NUM> and the receiver <NUM>. The IRL-SIG field <NUM> is subsequent to the L-SIG field in the OFDM PPDU <NUM>. In an example embodiment, the specified interleaver can be predetermined. In an example embodiment, the specified interleaver is particular to the wireless LAN PHY version (e.g. EHT <NUM>. 11be, or other version).

In the OFDM PPDU <NUM> of <FIG>, automatic detection of the specified wireless LAN PHY version of the PPDU, e.g. IEEE <NUM>. 11be PPDU, is conducted based on a check by comparing L-SIG with the recovery of L-SIG from the IRL-SIG field <NUM>. The IRL-SIG field <NUM> is represented in the data sub-carrier level. In IRL-SIG field <NUM>, the data sub-carriers are obtained by interleaving the data sub-carriers of L-SIG.

<FIG> illustrates an example method <NUM> of generating the IRL-SIG field <NUM> of the OFDM PPDU <NUM> of <FIG>. At step <NUM>, the transmitter <NUM> interleaves coded bits in L-SIG field with the specified interleaver to generate the IRL-SIG field <NUM>. At step <NUM> the coded bits of IRL-SIG field <NUM> are BPSK modulated using the symbol modulator <NUM>. At step <NUM>, the tone mapping block <NUM> of the transmitter <NUM> performs tone mapping of the BPSK modulated IRL-SIG. At step <NUM>, the IFFT block <NUM> of the transmitter <NUM> then applies OFDM modulation over the sub-carrier signals in accordance with the tone mapping, by performing an IFFT, arriving at an IRL-SIG symbol.

In an alternate example, step <NUM> is performed after step <NUM>. For example, the transmitter <NUM> first performs BPSK modulation on the IRL-SIG (which is the same as L-SIG at this point). Then, the transmitter <NUM> interleaves the BPSK modulated signals with a specified interleaver, prior to or as part of the tone mapping by the tone mapping block <NUM>.

<FIG> illustrates an example method <NUM> of receiving and detecting the IRL-SIG field <NUM> from the signal generated by the method <NUM> of <FIG>. At step <NUM>, at the receiver <NUM>, a signal (PPDU) in time domain is received and the FFT block <NUM> of the receiver <NUM> performs Fourier Transform to recover coded bits, and observes the first symbol after the L-SIG in the OFDM PPDU <NUM> (<FIG>). To determine whether the first symbol after the L-SIG is the IRL-SIG field <NUM>, at step <NUM>, the receiver <NUM> performs deinterleaving of the recovered bits of the first symbol after the L-SIG. At step <NUM>, the receiver <NUM> checks the recovered bits and compares the deinterleaved Rate, Reserved, Length, Parity and Tail recovered at step <NUM> with the L-SIG. If there is repetition detected in step <NUM> between the recovered bits from step <NUM> and the L-SIG, at step <NUM> the receiver <NUM> detects and concludes that the PPDU is a specified wireless LAN PHY version, e.g., IEEE <NUM>. 11be in this example. If the check at step <NUM> is not satisfied because the first symbol is found to be merely RL-SIG (non-interleaved), at step <NUM> a check is performed between the Rate, Reserved, Length, Parity and Tail of RL-SIG (which is the first symbol after L-SIG) and L-SIG. At step <NUM> if the check at step <NUM> is satisfied the receiver detects the received PPDU as being an HE PPDU (<NUM>. 11ax), or other checks are performed to determine whether the received PPDU is another wireless network type (which would be neither <NUM>. 11be nor <NUM>.

The alternate path <NUM> in <FIG> illustrates some instances where the HE PPDU (<NUM>. 11ax) is checked separately from, or in parallel with, the deinterleaving step <NUM>. At step <NUM>, the first symbol after L-SIG may be RL-SIG. At step <NUM>, the receiver <NUM> checks the recovered bits by comparing the Rate, Reserved, Length, Parity and Tail of the RL-SIG with the L-SIG. At step <NUM>, if the check is satisfied, the receiver detects the PPDU as being an HE PPDU (<NUM>.

Alternatively, the receiver <NUM> checks the deinterleaved subcarriers of the first received symbol after L-SIG by comparing with the subcarriers of L-SIG. If there is repetition between the deinterleaved subcarriers of the first symbol after the L-SIG and the subcarriers of the L-SIG, the receiver detects and concludes that the PPDU is a specified wireless LAN PHY version, e.g., IEEE <NUM>. 11be in this example. If the check is not satisfied, a second repetition check is performed between the subcarriers of the first symbol after the L-SIG and the subcarriers of the L-SIG. If the second repetition check between the subcarriers of the first symbol after the L-SIG and the subcarriers of the L-SIG is satisfied, the receiver detects and concludes that the received PPDU is an HE PPDU (<NUM> ax). If the second repetition check is not satisfied between the subcarriers of the first symbol after the L-SIG and the subcarriers of the L-SIG, other checks are performed to determine whether the received PPDU is another wireless network type (which would be neither <NUM>. 11be nor <NUM>.

In an example embodiment, multiple different specified interleavers can each respectively indicate a different wireless network version (PHY type) to generate the IRL-SIG. The IRL-SIG is an indication of one of a plurality of possible PHY types. In an example, the receiver <NUM> can be configured to perform blind selection of different possible interleavers of the received transmission until the L-SIG is matched with the recovered L-SIG from the detected IRL-SIG field <NUM>. In examples, the blind selection can be performed in a specified order or in random order.

<FIG> illustrates an example embodiment of an OFDM PPDU <NUM> having auto-detectable wireless LAN PHY version indication using a different version of the RL-SIG by way of a Scrambled RL-SIG (SRL-SIG) field <NUM>. The SRL-SIG field <NUM> is an identifier field for automatic detection of the wireless LAN PHY version. In the OFDM PPDU <NUM>, rather than interleaving as in <FIG>, the RL-SIG of a PPDU is modified by scrambling the L-SIG to generate a scrambled RL-SIG (SRL-SIG) field <NUM>. A scrambling sequence or scrambling function is used to generate the SRL-SIG field <NUM>. Referring to the OFDM PPDU <NUM> of <FIG>, for example, the SRL-SIG field <NUM> in this OFDM PPDU <NUM> instead of the IRL-SIG field <NUM> of the OFDM PPDU <NUM>.

The OFDM PPDU <NUM> can include one or more SIG fields particular to signaling information of the indicated wireless LAN PHY version, such as EHT Signaling Fields in this example. In an example embodiment, the specified scrambling sequence can be predetermined. In an example embodiment, the specified scrambling sequence is particular to the wireless LAN PHY version (e.g. EHT, or other version).

The generating and encoding of the OFDM PPDU <NUM> of <FIG> by the transmitter <NUM> can follow a similar method <NUM> as in <FIG>, with a scrambling step using the specified scrambling sequence (or scrambling function) performed instead of the interleaving step <NUM>. The receiving and interpreting of the OFDM PPDU <NUM> for auto-detection of the wireless LAN PHY version by the receiver <NUM> can follow a similar method <NUM> as in <FIG>, with a descrambling step using the specified scrambling sequence (or descrambling function) performed instead of the deinterleaving step <NUM>.

<FIG> illustrates an example of an OFDM PPDU <NUM> having auto-detectable wireless LAN PHY version indication using a modified RL-SIG, denoted as Cyclic Shifted RL-SIG (CS-RL-SIG) field <NUM>, in accordance with an example embodiment. The CS-RL-SIG field <NUM> is an identifier for automatic detection the wireless LAN PHY version. As shown in <FIG>, the OFDM PPDU <NUM> keeps the L-STF, L-LTF and L-SIG symbols unchanged. The RL-SIG symbol is the symbol after the L-SIG symbol. A modification of the RL-SIG signal in the time domain is performed, in which the RL-SIG signal in the time domain after the IFFT block <NUM> is cyclic shifted before adding cyclic prefix (CP) by the CP generator <NUM>. The cyclic shifting distance is known by both the transmitter <NUM> and the receiver <NUM>. At the coded bit level, the CS-RL-SIG <NUM> is a repeat of the L-SIG <NUM>.

The receiver <NUM> can perform autodetection of the PPDU <NUM> as being a specified wireless LAN PHY version, e.g., IEEE <NUM>. 11be, based a check of the repetition of a shifted version of CS-RL-SIG <NUM> compared with L-SIG <NUM>. In the OFDM PPDU <NUM>, the CS-RL-SIG <NUM> is a cyclic shifted repeat L-SIG signal <NUM> in the time domain. The CS-RL-SIG signal is obtained by cyclic shifting, in the time domain, a RL-SIG signal before adding cyclic prefix by cyclic prefix generator <NUM>.

<FIG> illustrates an example method <NUM> of generating and coding the CS-RL-SIG field <NUM> shown in <FIG>. The method <NUM> can be performed by the transmitter <NUM>. At step <NUM>, the coded bits of L-SIG <NUM> are BPSK modulated using the symbol modulator <NUM>. At step <NUM>, the tone mapping block <NUM> of the transmitter <NUM> tone maps the BPSK modulated L-SIG. At step <NUM>, the IFFT block <NUM> performs IFFT in accordance with the tone mapping, arriving at a RL-SIG symbol in time domain without cyclic prefix. At step <NUM>, the Cyclic Shifter <NUM> performs cyclic shifting at a specified cyclic shifting distance known by both the transmitter <NUM> and the receiver <NUM>, to generate a CS-RL-SIG symbol. At step <NUM>, the cyclic prefix generator <NUM> adds a cyclic prefix to the CS-RL-SIG symbol.

Detecting and decoding the coded CS-RL-SIG field is performed by the receiver <NUM> by, in time domain, removing the cyclic prefix by performing cyclic shifting to reverse the cyclic shifting from the method <NUM> of <FIG>. After FFT by the FFT block <NUM>, the recovered field from the coded CS-RL-SIG field <NUM> is compared with the L-SIG <NUM>, with a match being the indication of the specified wireless LAN PHY version, e.g., IEEE <NUM>. Otherwise, another wireless network version or legacy version may be detected. In an example, multiple different specified cyclic shifting distances can each respectively indicate a different wireless network version (PHY type) to generate the CS-RL-SIG.

<FIG> illustrates an example method <NUM> for enabling automatic wireless LAN PHY version detection within transmissions, in accordance with an example embodiment. At step <NUM>, the transmitter <NUM> generates a control signal for a transmission. In one example, the control signal includes i) a Legacy Signal (SIG) (L-SIG) symbol and ii) an identifier symbol which is generated from at least part of, but is not identical to, the L-SIG symbol, the identifier symbol indicates a wireless LAN PHY version of the transmission. In another example, the control signal includes a Legacy Signal (SIG) (L-SIG) field, a Repeated L-SIG (RL-SIG) field, and an identifier separate from the L-SIG field and the RL-SIG field, the identifier indicates i) a wireless LAN PHY version of the transmission and ii) a frame type of the transmission.

At step <NUM>, the transmitter <NUM> transmits the control signal. In some examples, at step <NUM> the transmitting of the control signal includes transmitting the identifier symbol after the L-SIG symbol. At step <NUM>, the receiver <NUM> receives the control signal. At step <NUM>, the receiver <NUM> detects the wireless LAN PHY version of the transmission from the control signal. At step <NUM>, the receiver <NUM> interprets the control signal according to the detected wireless LAN PHY version.

The described example embodiments of the control signal (preamble) for auto-detection of the wireless LAN PHY version can be applied to uplink transmission, not shown here. In an example, the control signal can be within a trigger frame to solicit uplink transmission. In an example, the control signal can be within a preamble of the uplink transmission.

<FIG> is a schematic diagram of an example wireless communication device <NUM>, in accordance with example embodiments. For example, the wireless communication device <NUM> may be the AP <NUM> or the STA <NUM>, and may include the transmitter <NUM> (<FIG>) or the receiver <NUM> (<FIG>). The wireless communication device <NUM> may be used for both Single User (SU) and multiple access communications within the wireless communication system <NUM>. Although <FIG> shows a single instance of each component, there may be multiple instances of each component in the wireless communication device <NUM> and the wireless communication device <NUM> could be implemented using parallel and distributed architecture. Some of the components in <FIG> are optional in some examples.

The wireless communication device <NUM> may include one or more processing devices <NUM>, such as a processor, a microprocessor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a dedicated logic circuitry, or combinations thereof. The wireless communication device <NUM> may also include one or more optional input/output (I/O) interface(s) <NUM>, which may enable interfacing with one or more optional input devices <NUM> and output devices <NUM>. The wireless communication device <NUM> may include one or more network interfaces <NUM> for wired or wireless communication with a network (e.g., an intranet, the Internet, a Peer-to-Peer (P2P) network, a Wide Area Network (WAN), a wireless WAN (WWAN), a Local Area Network (LAN), or a Radio Access Network (RAN)) or other node. Wireless networks may make use of wireless connections transmitted over an antenna <NUM>. The network interface(s) <NUM> may provide multiple access wireless communication via one or more transmitters or transmit antennas and one or more receivers or receive antennas, for example. In this example, one antenna <NUM> is shown, which may serve for multiple access transmission. However, in other examples there may be multiple antennas for transmitting and receiving. In some examples, an antenna array may be used. The wireless communication device <NUM> may also include one or more storage units <NUM>, which may include a mass storage unit such as a solid state drive, a hard disk drive, a magnetic disk drive or an optical disk drive.

The wireless communication device <NUM> may include one or more non-transitory memories <NUM> that can include physical memory <NUM>, which may include a volatile or non-volatile memory (e.g., a flash memory, a random access memory (RAM), or a read-only memory (ROM)). The memory <NUM> (as well as storage unit(s) <NUM>) may store instructions for execution by the processing device(s) <NUM>, such as to carry out processing such as those described in the present disclosure. The memory <NUM> may include other software instructions, such as for implementing an operating system (OS), and other applications/functions. In some examples, one or more data sets or modules may be provided by an external memory (e.g., an external drive in wired or wireless communication with the wireless communication device <NUM>) or may be provided by a transitory or non-transitory computer-readable medium. Examples of non-transitory computer readable media include a RAM, a ROM, an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a flash memory, a CD-ROM, or other portable memory storage.

In some examples, there may be a bus <NUM> providing communication among components of the wireless communication device <NUM>. The bus <NUM> may be any suitable bus architecture including, for example, a memory bus, a peripheral bus or a video bus. Optional input device(s) <NUM> (e.g., a keyboard, a mouse, a microphone, a touchscreen, or a keypad) and optional output device(s) <NUM> (e.g., a display, a speaker or a printer) are shown as external to the wireless communication device <NUM>, and connected to optional I/O interface(s) <NUM>. In other examples, one or more of the input device(s) <NUM> or the output device(s) <NUM> may be included as a component of the wireless communication device <NUM>.

The transmitter <NUM> and the receiver <NUM> may be included as one or more components of the wireless communication device <NUM>. For example, the transmitter <NUM> and the receiver <NUM> may be included as a single component for transmitting and receiving radio frequency (RF) analog signals. In other examples, the transmitter <NUM> and the receiver <NUM> may be included as two separate components for transmitting and receiving radio frequency (RF) analog signals respectively. The transmitter <NUM> may provide transmission of PPDUs and the receiver <NUM> may receive the PPDU.

When the wireless communication device <NUM> is the AP <NUM>, communication with selected or associated STAs <NUM> can be performed using the antenna <NUM>. The processing device <NUM> may carry out the steps and functions described herein. When the wireless communication device <NUM> is a STA <NUM>, communications with the AP <NUM> can be performed via the antenna <NUM>.

The wireless communication device <NUM> also includes a power supply block <NUM> to supply power to the wireless communication device <NUM>. In some examples, the power supply block <NUM> can include a battery. In some examples, the power supply block <NUM> includes a power adapter (e.g., AC/DC or DC/DC) for connection to an external power source and can be used for charging the battery.

In at least some examples, instructions that cause the processing device <NUM> to carry out methods in accordance with example embodiments are stored in storage unit(s) <NUM> or memory <NUM> of the wireless communication device <NUM>. In some examples, the processing device <NUM> may be one or more controllers, which may comprise a modulator or a processor. Example systems and methods described herein, in accordance with examples, can be implemented by the one or more controllers. The one or more controllers can comprise hardware, software, or a combination of hardware and software, depending on the particular component and function. In some examples, the one or more controllers can include analog or digital components, and can include one or more processors, one or more non-transitory storage mediums such as memory storing instructions executable by the one or more processors, one or more transceivers (or separate transmitters and receivers), one or more signal processors (analog or digital), and one or more analog circuit components.

Example embodiments can applied to MU communication, single user (SU) communication, trigger based (TB) communication, or extended range (ER) TB communication.

An example embodiment is a non-transitory computer-readable medium which stores instructions that when executed by a processing device causes the processing device to perform any of the described methods, processes or functions.

The example embodiments described above may be implemented by using hardware only or by using software and a necessary universal hardware platform. Based on such understandings, the technical solution of some example embodiments may be embodied in the form of a software product. The software product may be stored in a non-volatile or non-transitory storage medium, which can be a compact disk read-only memory (CD-ROM), Universal Serial Bus (USB) flash disk, or a removable hard disk. The software product includes a number of instructions that enable a computer device (personal computer, server, or network device) to execute the methods provided in the example embodiments. The software product may additionally include a number of instructions that enable a computer device to execute operations for configuring or programming a digital logic apparatus in accordance with example embodiments.

Example apparatuses and methods described herein, in accordance with example embodiments, can be implemented by one or more controllers. The controllers can comprise hardware, software, or a combination of hardware and software, depending on the particular application, component or function. In some example embodiments, the one or more controllers can include analog or digital components, and can include one or more processors, one or more non-transitory storage mediums such as memory storing instructions executable by the one or more processors, one or more transceivers (or separate transmitters and receivers), one or more signal processors (analog and/or digital), and/or one or more analog circuit components.

In the described methods or block diagrams, the boxes may represent events, steps, functions, processes, modules, messages, and/or state-based operations, etc. Although some of the above examples have been described as occurring in a particular order, it will be appreciated by persons skilled in the art that some of the steps or processes may be performed in a different order provided that the result of the changed order of any given step will not prevent or impair the occurrence of subsequent steps. Furthermore, some of the messages or steps described above may be removed or combined in other embodiments, and some of the messages or steps described above may be separated into a number of sub-messages or sub-steps in other embodiments. Even further, some or all of the steps may be repeated, as necessary. Elements described as methods or steps similarly apply to systems or subcomponents, and vice-versa. Reference to such words as "sending" or "receiving" could be interchanged depending on the perspective of the particular device.

Claim 1:
A method for enabling wireless local area network, WLAN, physical layer, PHY, version detection, performed by a wireless communication device (<NUM>), the method comprising:
generating (<NUM>) a control signal (<NUM>) for an uplink transmission, the control signal including:
a first identifier (<NUM>) indicating a WLAN PHY version of the transmission; and
transmitting (<NUM>) the control signal (<NUM>) in a trigger frame, wherein the first identifier (<NUM>) is an identifier field or identifier subfield of the trigger frame.