TW201632022A - Wireless apparatus for high-efficiency (HE) communication with additional subcarriers - Google Patents

Abstract

Embodiments of an access point and method for high-efficiency WLAN (HEW) communication are generally described herein. In some embodiments, the access point may be configured to operate as a master station and may configure an HEW frame to include a legacy signal field (L-SIG), an HEW signal field (HEW SIG-A) following the L-SIG, and one or more HEW fields following the HEW SIG-A. The L-SIG may be configured for transmission using a legacy number of data subcarriers, a legacy number of pilot subcarriers and a number of additional reference subcarriers modulated with a known reference sequence. At least one symbol of the HEW SIG-A and the one or more HEW fields following the HEW SIG-A of the HEW frame may be configured for transmission using additional data subcarriers. The additional data subcarriers may correspond to the additional reference subcarriers of the L-SIG.

Description

Wireless device for high performance (HE) communication with additional subcarriers

Priority claim

The present application claims the benefit of priority to U.S. Patent Application Serial No. 14/338,137, filed on Jul. 22, 2014, which is hereby incorporated herein in No., dated November 19, 2013, serial number 61/973, 376, submitted on April 1, 2014, serial number 61/976,951, submitted on April 8, 2014, serial number 61/986, 256, Submitted on April 30, 2014, serial number 61/986, 250, submitted on April 30, 2014, serial number 61/991, 730, submitted on May 12, 2014, serial number 62/013, 869, 2014 Submitted on June 18, and serial number 62/024,801, filed July 15, 2014, each of which is incorporated herein in its entirety by reference.

Field of invention

Embodiments relate to wireless networks. Some embodiments relate to Wi-Fi networks and wireless local area networks (WLANs) operating in accordance with one of the IEEE 802.11 standards, such as the IEEE 802.11ac standard or the IEEE 802.11ax SIG (referred to as DensiFi). Some embodiments relate to high performance WLAN (HEW) communication.

Background of the invention

Wi-Fi communication has evolved towards increasing data rates (eg, from IEEE 802.11a/g to IEEE 802.11n to IEEE 802.11ac). The upcoming IEEE 802.11ax standard for high performance WLAN (HEW) is an evolutionary standard for this standard. Therefore, there is a general need in HEW for achieving an increase in data capacity without additional burden while maintaining compatibility with legacy systems. There is a general need in HEW for achieving increased data capacity while minimizing the burden.

According to an embodiment of the present invention, a wireless device is specifically proposed for operation as a high performance (HE) station (HE-STA), the device comprising: a memory; and a processing circuit Equipped with: decoding one of the HE data units, the legacy signal field (L-SIG), the L-SIG comprising four reference subcarriers, the four reference subcarriers comprising two edges at each edge of a 20 MHz channel a subcarrier; and decoding one HE signal field (HE-SIG-A) of the HE data unit, the HE-SIG-A including a total number of data subcarriers, including in the frequency corresponding to the L-SIG Four data subcarriers of the four reference subcarriers, the four data subcarriers comprising two subcarriers at each edge of the 20 MHz channel, wherein the four reference subcarriers of the L-SIG It is included in the L-SIG in addition to an old number of data subcarriers.

100‧‧‧HEW Network

102‧‧‧Main station

104‧‧‧HEW Station

106‧‧‧Old station

200‧‧‧Old frame

202‧‧‧Old Short Training Field (L-STF)

204‧‧‧Old Long Training Field (L-LTF)/L-LTF

206‧‧‧Old Signal Field (L-SIG)/L-SIG

208‧‧‧VHT signal field/VHT-SIG-A

209‧‧‧VHT-STF

210‧‧‧VHT-LTF

212‧‧‧VHT-SIG-B

216‧‧‧ data

400‧‧‧HEW frame

406‧‧ Old Signal Field (L-SIG)/L-SIG/Reference Subcarrier L-SIG

408‧‧‧HEW Signal Field (HEW SIG-A)/HEW SIG-A

408A‧‧‧First symbol (HEW SIG-A1)/HEW SIG-A1

408B‧‧‧Second symbol (HEW SIG-A2)

410‧‧‧HEW-STF

414‧‧‧HEW Scheduling Field (HEW-SCH)/HEW-SCH

416‧‧‧HEW data field/data field

601‧‧‧DC subcarrier

602‧‧‧Data Subcarrier/Old Data Subcarrier

604‧‧‧pilot subcarrier

605‧‧‧protective tone

606‧‧‧Reference subcarrier/old pilot subcarrier

700‧‧‧HEW device

702‧‧‧Physical Layer (PHY) Circuit/PHY

704‧‧‧Media Access Control Layer Circuit (MAC)/MAC

706‧‧‧Processing circuit

708‧‧‧ memory

800‧‧‧ procedures

802~808‧‧‧ operation

1 illustrates an HEW network in accordance with some embodiments; FIG. 2 illustrates an old frame; FIG. 3 is a table illustrating the number of subcarriers for various fields of a legacy frame; FIG. 4 illustrates an HEW frame in accordance with some embodiments. 5 is a table illustrating the number of subcarriers for various fields of an HEW frame in accordance with some embodiments; FIG. 6A illustrates subcarrier allocation for a legacy system; FIG. 6B illustrates subcarriers for HEW, in accordance with some embodiments. Assignment; FIG. 7 illustrates a HEW communication device in accordance with some embodiments; and FIG. 8 illustrates a procedure for HEW communication with increased information bits, in accordance with some embodiments.

Detailed description of the preferred embodiment

The description and drawings are to be considered as illustrative of the embodiments Other embodiments may incorporate structural changes, logic changes, electrical changes, process variations, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. The embodiments set forth in the scope of the claims are intended to cover all such equivalents.

FIG. 1 illustrates a HEW network in accordance with some embodiments. The HEW network 100 can include a primary station (STA) 102 and a plurality of HEW stations 104 (ie, HEW) Device) and a plurality of old stations 106 (legacy devices). The primary station 102 can be arranged to communicate with the HEW station 104 and the legacy station 106 in accordance with one or more of the IEEE 802.11 standards. In some embodiments, the primary station 102 can be arranged to communicate with the HEW station 104 in accordance with the IEEE 802.11ax standard for HEW. In some embodiments, the primary station 102 can be an access point (AP), although the scope of the embodiments in this aspect is not limited. Although HEW refers to high-performance WLAN, it can also refer to high-performance W-Fi.

According to an embodiment, the primary station 102 can include a physical layer (PHY) and medium access control layer (MAC) circuitry that can be arranged to compete for wireless media (eg, during a contention period) to receive mutual exclusion control duration HEW for the media Control cycle (ie, transmission opportunity (TXOP)). The primary station 102 can transmit the HEW primary synchronization transmission at the beginning of the HEW control period. During the HEW control period, the HEW station 104 can communicate with the primary station 102 in accordance with a non-contention based scheduling multiple access technique. This is different from conventional Wi-Fi communication, in which devices communicate according to contention-based communication technologies rather than non-contention multiple access technologies. The legacy station 106 avoids communication during the HEW control cycle. In some embodiments, the primary synchronous transmission may be referred to as HEW control and scheduled transmission.

According to an embodiment, the primary synchronization transmission may include a multi-device HEW preamble arranged to signal and identify data fields of the plurality of scheduled HEW stations 104. The primary station 102 can be further arranged to transmit (in the downlink direction) and/or receive (in the uplink direction) one or more of the data fields to/from the scheduled HEW station 104 during the HEW control period. In such embodiments, the primary station 102 may include training fields in the multi-device HEW preamble to allow scheduling of HEW stations. Each of 104 performs synchronization and initial channel estimation.

According to some embodiments, the HEW station 104 may be a Wi-Fi or IEEE 802.11 group of stations (STAs) that are further assembled for HEW operation (eg, according to IEEE 802.11ax). The HEW station 104 can be configured to communicate with the primary station 102 in accordance with a non-contention-based multiple access technique, such as scheduled orthogonal frequency division multiple access (OFDMA) technology, during the HEW control period, and can be configured to receive and Decode the HEW pre-multiple device HEW pre-text. The HEW station 104 can also be configured to decode the indicated data fields received by the primary station 102 during the HEW control period.

According to an embodiment, the primary station 102 can assemble an HEW frame to include a legacy signal field (L-SIG), a HEW signal field followed by an L-SIG (HEW SIG-A), and a HEW SIG-A 408 followed by One or more HEW fields. The L-SIG can be configured to transmit using the old number of data subcarriers, the old number of pilot subcarriers, and a certain number of additional reference subcarriers modulated by known reference sequences. At least one symbol of the HEW SIG-A and one or more HEW fields following the HEW SIG-A in the HEW frame may be combined to transmit using additional data subcarriers. The additional data subcarriers may correspond to additional reference subcarriers of the L-SIG. In such embodiments, the increased data capacity is achieved by increasing the number of signaling bits without increasing the packet burden. These embodiments are discussed in more detail below.

Figure 2 illustrates an old frame. The old frame 200 may include an old short training field (L-STF) 202, an old long training field (L-LTF) 204, a legacy signal field (L-SIG) 206, and a VHT signal field (VHT-SIG- A) 208, VHT-STF 209, VHT-LTF 210, VHT-SIG-B 212 and data 216. For the 20MHz channel, the L-SIG 206 and some fields following the L-SIG 206 (for example, VHT-SIG-A 208) can use the old number of data subcarriers (ie, 48) and the old ones. The number of pilot subcarriers (ie, four).

3 is a table illustrating the number of subcarriers used for various fields of a legacy frame. As shown in FIG. 3, for a 20 MHz channel, the L-SIG 206 and some fields following the L-SIG 206 (eg, VHT-SIG-A 208) may use the old number of data subcarriers (ie, 48) and the old number of pilot subcarriers (ie, 4) for a total of 52 subcarriers. For 40 MHz channels, L-SIG 206 and VHT-SIG-A 208 can utilize a total of 104 subcarriers, and for 80 MHz channels, L-SIG 206 and VHT-SIG-A 208 can utilize a total of 208 subcarriers, and for For the 160 MHz channel, the L-SIG 206 and VHT-SIG-A 208 can utilize a total of 416 subcarriers.

FIG. 4 illustrates an HEW frame in accordance with some embodiments. The HEW frame 400 may include an old short training field (L-STF) 202, an old long training field (L-LTF) 204, a legacy signal field (L-SIG) 406, and a HEW signal field (HEW SIG-A). 408, HEW-STF 409, HEW-LTF 210, HEW-SIG-B 212, HEW Scheduling Field (HEW-SCH) 414, and data 216. According to an embodiment, when an access point is grouped to operate as a primary station 102 for HEW communication, the access point can be combined with the HEW frame 400 to include the L-SIG 406, the HEW SIG followed by the L-SIG 406. -A 408 and HEW SIG-A 408 followed by one or more HEW fields. The L-SIG 406 can be configured to transmit using the old number of data subcarriers, the old number of pilot subcarriers, and a certain number of additional reference subcarriers modulated by known reference sequences. At least one symbol of the HEW SIG-A 408 and the HEW SIG-A 408 in the HEW frame 400 are followed by One or more HEW fields can be combined to transmit using additional data subcarriers. The additional data subcarriers may correspond to additional reference subcarriers of L-SIG 406. The increased data capacity is achieved by increasing the number of signaling bits in the HEW SIG-A 408 without increasing the packet burden.

FIG. 5 is a table illustrating the number of subcarriers for various fields of an HEW frame, in accordance with some embodiments. As shown in FIG. 5, for a 20 MHz channel, the L-SIG 406 can use an old number of data subcarriers (ie, 48), a number of reference subcarriers modulated by a known reference sequence (eg, Four) and the old number of pilot subcarriers (ie, four) for a total of 56 subcarriers. For a 20 MHz channel, the HEW SIG-A 408 can use the old number of data subcarriers (ie, 48), a number of reference subcarriers (eg, four) modulated by known reference sequences, and old There are a number of pilot subcarriers (ie, 4) for a total of 56 subcarriers. For 40MHz channels, L-SIG 406 and HEW SIG-A 408 can utilize a total of 114 subcarriers, and for 80MHz channels, L-SIG 406 and HEW SIG-A 408 can utilize a total of 242 subcarriers, and for 160MHz channels In this regard, L-SIG 406 and HEW SIG-A 408 may utilize, for example, a total of 484 subcarriers.

Figure 6A illustrates subcarrier allocation for a legacy system. The subcarrier allocation illustrated in FIG. 6A can be used for L-SIG 206 (FIG. 2) and VHT-SIG-A 208 (FIG. 2), and illustrates a total of 52 subcarriers (between position -26 and position +26).

FIG. 6B illustrates subcarrier allocation for HEW in accordance with some embodiments. The subcarrier allocation illustrated in FIG. 6B can be used for L-SIG 406 (FIG. 4), and one or more fields followed by L-SIG 406 include HEW SIG-A 408 (FIG. 4). And a total of 56 subcarriers are located (between position -28 and position +28). The subcarrier allocation illustrated in FIG. 6B may include an old number of data subcarriers 602, an old number of pilot subcarriers 604, and a number of additional reference subcarriers 606.

According to some embodiments, the L-SIG 406 can be configured to use the old number of data subcarriers 602, the old number of pilot subcarriers 604, and a certain number of additional reference subcarriers 606 that are modulated by known reference sequences. Transfer. At least one symbol of HEW SIG-A 408 and one or more HEW fields following HEW SIG-A 408 in HEW frame 400 may also be combined to transmit using additional data subcarriers 606. The additional data subcarriers correspond to the additional reference subcarriers 606 of the L-SIG 406.

According to some embodiments, the number of data subcarriers 602 may be forty-eight for a 20 MHz channel, and the number of pilot subcarriers 604 may be four, and additional sub-modules modulated by known reference sequences. The number of carriers 606 can be four, for a total of sixty-four subcarriers, including additional null subcarriers (eg, DC subcarrier 601 and guard band subcarriers). The number of data subcarriers of the HEW data field 416 followed by the HEW SIG-A 408 may be fifty two. In these embodiments, for the 20 MHz channel, the signals including the L-SIG 408 and L-SIG 408 followers are transmitted over a total of fifty-six subcarriers of the L-SIG 408. The number of data subcarriers in the HEW data field 416 can be fifty two (e.g., forty eight legacy data subcarriers and four additional data subcarriers). As illustrated in FIG. 6, L-SIG 406 may also include DC subcarrier 601 and guard tone 605. In such embodiments, L-SIG 406 may include OFDM symbols, which may be generated using a 64-point FFT. In some implementations In an example, HEW frame 400 can be transmitted via a wider bandwidth that can include multiple 20 MHz channels. In some embodiments, the bandwidth can be one of 20 MHz, 40 MHz, 80 MHz, or 160 MHz. In some embodiments, a 320 MHz bandwidth can be used.

According to some embodiments, when the HEW frame 400 includes a legacy long training field (L-LTF) 404 prior to the L-SIG 406, the access point can be configured to factor the L-SIG 406 by a factor of 56/52. Full subcarrier power allocation scaling (eg, increase). In some alternative embodiments, the hardware processing circuitry can be configured to scale (eg, reduce) the full subcarrier power allocation of L-LTF 404 by a factor of 52/56. In such embodiments, the full subcarrier power allocation of the scale L-LTF 204 or L-SIG 406 can help maintain the same overall power level of these fields to reduce any effects on the decoding performance of legacy devices.

In some embodiments, for a 20 MHz channel, the pilot subcarrier 604 is located at positions -21, -7, 7, 21 relative to the DC subcarrier 601, and the additional reference subcarrier 606 is located relative to the DC subcarrier. The location of 601 is -28, -27, 27, 28. In these embodiments, the additional data subcarriers 606 used by one or more HEW fields followed by HEW SIG-A 408 and HEW SIG-A 408 may also be located at positions -28 relative to DC subcarrier 601. , -27, 27, 28 places.

In some embodiments, the known reference sequence modulated on the additional reference subcarrier 606 of the L-SIG 406 may be used by the receiving HEW station 104 (FIG. 1) for channel estimation to allow the receiving HEW station 104 to demodulate and The additional data subcarriers of the HEW SIG-A 408 and the additional data subcarriers of one or more HEW fields followed by the HEW SIG-A 408 are decoded. In these embodiments, The HEW frame 400 can also be assembled to include an old short training field (L-STF) 202 and an old long training field (L-LTF) 204 prior to the L-SIG 406. L-STF 202 and L-LTF 204 can be conventional old training fields. According to an embodiment, the channel estimate for the subcarriers in FIG. 6A may be determined by L-LTF 204 (ie, all subcarriers except for additional reference subcarriers 606 in FIG. 6B), and the channels for additional subcarriers 606 The estimate may be determined by the additional reference subcarrier 606 of the L-SIG 406.

In some embodiments, the access points may be configured to scale (ie, increase) the full subcarrier power allocation of L-SIG 406 by a factor of B/A, where A is the old number of data subcarriers 602 The old number of pilot subcarriers 604 is added, and B is the number of old number of pilot subcarriers 604 of data subcarrier 602 plus the number of additional subcarriers 606.

In some embodiments, the pilot subcarrier 604 of the L-SIG 408 and the additional reference subcarrier 606 carry information previously known to the receiver (eg, a known reference sequence. In some embodiments, the L-SIG 408 Pilot subcarrier 604 and additional reference subcarrier 606 may have the same modulation (eg, BPSK +1 or BPSK-1), while in other embodiments, pilot subcarrier 604 of L-SIG 408 and additional references Subcarriers 606 may have different modulations (eg, pilot subcarrier 604 may have BPSK +1 and additional reference subcarrier 606 may have BPSK-1).

In some embodiments, one or more HEW fields following HEW SIG-A 408 in HEW frame 400 may include HEW data field 416 and HEW scheduling field prior to data field 416 (HEW-SCH) ) 414. The HEW-SCH 414 can include scheduling information for one or more HEW stations 104, The HEW stations 104 are scheduled to communicate with the access point 102 during the data field 416 in accordance with scheduled orthogonal frequency division multiple access (OFDMA) techniques. In such embodiments, HEW-SCH 414 and data field 416 may utilize additional data subcarriers 606 for data capacity increase. For example, the number of data subcarriers can be increased from 48 to 52. In some embodiments, scheduled OFDMA techniques may include uplink or downlink communications, and may also include uplink or downlink partition multiple access (SDMA) usage, although in this aspect embodiments The scope is not limited.

In some embodiments, HEW SIG-A 408 includes at least a first symbol (HEW SIG-A1) 408A and a second symbol (HEW SIG-A2) 408B. In these embodiments, the information bits carried by the HEW SIG-A1 408A may be mapped to the legacy data subcarrier 602, and the pilot subcarriers of the HEW SIG-A1 408A may be mapped to the legacy pilot subcarrier 604. The additional reference subcarriers 606 of the HEW SIG-A1 408A may be modulated using known reference sequences, and the information bits carried by the HEW SIG-A2 408B may be mapped to the data subcarrier 602 and the additional reference subcarrier 606. The pilot subcarriers of HEW SIG-A2 408B may be mapped to legacy pilot subcarriers 604. In these embodiments HEW SIG-A2 408B may have an additional four subcarriers for data distribution (eg, up to 52 data subcarriers for a 20 MHz channel). In such embodiments, a separate encoder/decoder may be used for HEW SIG-A1 408A and HEW SIG-A2 408B, unlike conventional joint encoders/decoders. In such embodiments, the additional reference subcarriers of HEW SIG-A1 408A may be utilized in the same manner, with an additional four reference subcarriers 606 being used for L-SIG 406 (eg, for channel estimation) to Provides more stability in low SNR conditions Channel estimation because the receiver can be configured to average the reference subcarriers of L-SIG 406 and HEW SIG-A1 408.

In some embodiments, HEW SIG-A 408 may include additional symbols such as HEW SIG-A3 and HEW SIG-A4 and the like. In such embodiments, the additional symbols of HEW SIG-A 408 may be similarly combined into HEW SIG-A2 408B using additional subcarriers for data allocation. In such embodiments, the additional symbols of HEW SIG-A 408 and the number of additional symbols that may be used may depend on the amount of information to be carried.

In some embodiments, when the access point 102 operates as a primary station, the access points can be configured to compete for wireless media during the contention period to receive control over the media for the duration of the HEW control period and during the HEW control period. HEW, wherein during the HEW control period, the primary station has a mutually exclusive use of wireless media for communicating with the scheduled HEW station 104 in accordance with a non-contention based multiple access technique. In some embodiments, the non-contention multiple access based technology may be scheduled OFDMA technology and may include uplink or downlink communications, and may also include the use of uplink or downlink SDMA, although in this state The scope of the examples is not limited. In such embodiments, the access point 102 can transmit multiplexed downlink data to each of the plurality of scheduled HEW stations during the HEW control period, or receive multiple schedules during the HEW control period. The uplink data of the multiplex transmission of the HEW station. The downlink data from each of the schedule stations 104 may correspond to one link and include one or more streams. The uplink data from each of the scheduling stations may correspond to one link and include one or more streams. Downlink data and uplink data may be time multiplexed, frequency multiplexed, and/or spatially multiplexed lost. In such embodiments, the access point 102 can include the number of LTFs in the LTF portion 410 of the HEW preamble, and can include a HEW Scheduling Field (HEW-SCH) 414 followed by an LTF portion. In such embodiments, the access point 102 can be grouped with HEW frames to include legacy preambles prior to the HEW preamble. In such embodiments, HEW-SCH 414 can be configured to identify one or more of: modulation parameters for each link, coding type for each link, whether each link is a single User (SU) link or multi-user (MU) link; and the number of streams for each link. Each data field 416 can be associated with a single user (SU) link or a multi-user (MU) link, and each link can be configured to provide multiple data streams. In some embodiments, the primary station can provide an indication of the number of LTFs included in the LTF portion of the HEW preamble. In some embodiments, the selection of the number of LTFs to be included in the HEW preamble may be based on the maximum number of streams to be transmitted on a single link, although the scope of the embodiments is not limited in this aspect.

According to an embodiment, the communication station 104 assembled for HEW communication can be configured to receive the HEW frame 400. The HEW frame 400 includes at least the L-SIG 406, the HEW SIG-A 408 followed by the L-SIG 406, and HEW SIG-A 408 followed by one or more HEW fields. In such embodiments, HEW station 104 can be configured to decode data subcarrier 602 of L-SIG 406 to determine length and rate information, and to calculate channel estimates for additional reference subcarriers 606 of L-SIG 406 from known reference sequences. The value is used, and the channel estimate is used to decode at least one symbol of HEW SIG-A 408 with additional data subcarriers of one or more HEW fields following HEW SIG-A 408.

In some embodiments, the HEW station 104 can be further configured to avoid The additional reference subcarrier 606 of the L-SIG 406 is not decoded. These additional reference subcarriers 606 of L-SIG 406 are suitable for determining channel estimates and not carrying any data.

In some embodiments, the HEW station 104 can be configured to decode the HEW SIG-A 408 using channel estimates determined from legacy training fields (eg, L-LTF 204) and additional reference subcarriers L-SIG 406. Data subcarrier. The data subcarriers of the HEW SIG-A 408 correspond to the data subcarriers of the L-SIG 406, and the additional data subcarriers correspond to the additional reference subcarriers 606 of the L-SIG 406. In these embodiments, all (eg, 52) data subcarriers of HEW-SIG A 408 (additional data subcarriers (corresponding to additional reference subcarriers 606 of L-SIG 406) and legacy data subcarriers ( Data subcarriers 602)) corresponding to L-SIG 406 can be demodulated and decoded together. For example, a 64-point FFT can be used. Conventionally, legacy signal fields do not utilize additional reference subcarriers 606.

In some embodiments, the HEW station 104 can further be configured to determine whether the received frame is an HEW frame 400 or an old frame, based on whether the value in the length field of the L-SIG is divisible by three, or A phase rotation based on BPSK modulation applied to the first and second symbols of the subsequent signal field.

In some embodiments, HEW station 104 may utilize additional reference subcarriers 606 of HEW SIG-A1 408A and additional reference subcarriers 606 of L-SIG 406 for channel estimation (eg, using combining or averaging techniques) . In such embodiments, HEW station 104 may decode HEW SIG-A2 408B based on channel estimates obtained from L-LTF 204, L-SIG 406, and HEW SIG-A1 408A, although in this aspect the embodiment Unrestricted scope system.

According to some embodiments, the primary station 102 can be arranged to select a number of long training fields (LTFs) to be included in the HEW preamble of the HEW frame. The HEW frame can include multiple links for transmitting multiple data streams. The primary station 102 can also sequentially transmit a selected number of LTFs as part of the multi-device HEW preamble and sequentially transmit a plurality of data fields to each of the plurality of scheduled HEW stations 104. The data field can be part of the HEW frame. Each data field may correspond to one of the links and may include one or more data streams. In some embodiments, the data field may be referred to as a packet. The primary station 102 can also be arranged to receive packets from the HEW station 104 in the uplink direction during the HEW control period.

In some embodiments, the primary station 102 can be arranged to assemble a multi-device HEW preamble to include a HEW Control Signal Field (HEW-SCH) to identify and signal each of the data fields of the HEW frame. In such embodiments, a single HEW preamble is included in the HEW frame, which is different from the prior art that is included for each link.

In such embodiments, the HEW primary synchronization transmission that may be transmitted at the beginning of the HEW control period may include a multi-device HEW preamble. The data field of the HEW frame may be transmitted by the primary station 102 during the HEW control period, in the downlink direction, after the multi-device HEW preamble, and/or by the primary station 102 in the uplink direction.

In some embodiments, the links of the HEW frames (eg, data fields) can be grouped to have the same bandwidth, and the bandwidth can be one of: 20 MHz, 40 MHz, or 80 MHz connected bandwidth or 80+80 MHz ( 160MHz) Unconnected bandwidth. In some embodiments, a 320 MHz connected bandwidth can be used. In some embodiments, a bandwidth of 1 MHz, 1.25 MHz, 2.5 MHz, 5 MHz, and/or 10 MHz can also be used. In these embodiments, each link of the HEW frame can be configured to transmit a large amount of spatial streams.

Embodiments disclosed herein increase the number of information bits carried in OFDM symbols that can be transmitted after the Wi-Fi preamble (IEEE 802.11a/g) portion (L-SIG). Because HEW is an evolutionary standard of previous standards and needs to coexist with legacy systems, HEW-specific transmissions can be started in the old format. The old-style portion of the foregoing may include L-STF 202, L-LTF 204, and L-SIG 206 (see FIG. 2) to allow legacy devices to detect HEW transmissions with appropriate delays. After decoding the L-SIG 206, if the HEW device can identify each transmission as an HEW packet or a legacy packet, the remaining packets can be transmitted in a HEW specific format. However, any signal field after the L-SIG can be limited to the channel estimate obtained from the L-LTF until a new HEW-LTF is transmitted. This limitation is the case with previous version standards, namely IEEE 802.11n/ac. As depicted in FIG. 2, in IEEE 802.11ac, VHT-SIG-A is followed by L-SIG, and as identified in the table of FIG. 3, the number of subcarriers matches the L-SIG. The OFDMA symbols transmitted after the VHT-LTF have a larger number of data subcarriers because the receiver has channel estimates for a larger number of subcarriers only after processing the VHT-LTF.

Due to this limitation, the number of information bits carried in the VHT-SIG-A 208 is limited to the number of information bits carried in the L-SIG because it has the same number of data subcarriers and uses the same modulation order and code. rate. Embodiments disclosed herein are provided for use, for example, in HEW SIG-A 408 The increase in the number of waves (for example, to 20, 40, 80, and 160 MHz, respectively, to 56, 112, 224, and 448 subcarriers). This increase in the number of subcarriers can be directly translated into an increase in the number of information bits. OFDMA is known to be a promising technology for HEW and OFDMA may require additional information to be signaled and thus will carry more bits at HEW SIG-A 408, such embodiments allow for more efficient OFDMA bit allocation. It should be noted that carrying more information bits in the HEW SIG-A 408 is extremely valuable, because in other cases, another complete symbol may be required in the foregoing, thereby increasing the overall contract burden. Because the focus on HEW is performance, organizations that increase the number of information bits without adding any additional burden are key to successful design and increase the chances of direct adoption in the standard.

According to an embodiment, additional reference subcarriers are introduced into the L-SIG 406 without affecting the performance of the legacy device 106 in detecting the L-SIG 406. Legacy device 106 is unaware of the existence of additional reference subcarriers and can decode L-SIG 406 as previously described. However, HEW device 104 can be configured to learn additional reference subcarriers and use it to obtain channel estimates for its corresponding subcarriers, while decoding L-SIGs similar to legacy devices. These newly obtained channel estimates obtained via the use of reference subcarriers are used for HEW receivers for decoding subsequence OFDM symbols and in particular for decoding HEW SIG-A 408 with an increased number of subcarriers.

One of the goals of HEW is to adopt a method that improves the performance of Wi-Fi and especially the performance of dense deployment. Each new revision to the Wi-Fi standard utilizes additional signaling techniques, so subsequent correction systems can identify each transmission and classify it as one of the legacy system transmissions or from one of the new revision criteria. In Wi-Fi, in order to maintain legacy capabilities, the previous part of the packet has been added, and new fields with various modulation formats have been added so that new releases can be identified. According to an embodiment, the HEW device 104 is capable of identifying HEW packets from legacy packets. In such embodiments, the HEW frame 400 can be assembled to have the format shown in FIG. It should be noted that the precise number of fields, their order in time and duration do not change the primary concepts and such embodiments that can be applied to more general formats and other bandwidths.

According to an embodiment, the OFDM structure of the L-SIG utilizes a 64-FFT with subcarrier allocation as shown in Figure 6A, where the pilots are located at positions (-21, -7, 7, 21). The pilot tones are specified after the encoder and interleaver. Some embodiments may extend the L-SIG to 56 subcarriers, which is similar to the subcarrier allocation as shown in Figure 6B. The newly designated reference subcarriers (-28, -27, 27, 28) illustrated in Figure 6B may be known to the HEW receiver and may be used for channel estimation, which will be used for subsequence OFDM symbols as depicted in Figure 4. HEW SIG-A. Similar to pilot tones, these reference subcarriers do not experience an encoder and an interleaver. The reference subcarrier is specified to have a certain polarity. Those skilled in the art can run a computer search program to find out the exact value. In general, values are selected for a combination of random and decisive choices of information bits in the L-SIG to provide an optimal peak-to-average power ratio (PAPR). A simple example of this can be an L-SIG extension similar to the extension of L-LTF to HT-LTF in Greenfield 11n format. The L-SIG with additional reference subcarriers can also utilize a 64-bit FFT.

Adding such new reference symbols to the L-SIG may have a negative impact on detecting the L-SIG by the legacy device 106 or the HEW device 104. Furthermore, since it can only be one of many symbols in the packet, it will Does not affect adjacent channel interference. However, attention should be placed on full-tone power calibration. With this extension, the full-tone power scaling of the L-LTF can be different from the full-tone power scaling of the L-SIG, which can affect the decoding performance of legacy devices. To make the full tone power levels the same, in some embodiments, the L-LTF symbol power can be reduced (e.g., by 52/56) depending on the number of subcarriers.

According to an embodiment, the HEW receiver continues to decode the L-SIG 406, which is identical to the legacy operation by deinterleaving and decoding 52 legacy subcarriers. Additionally, the HEW station 104 can then calculate channel estimates for the subcarriers (e.g., subcarriers at locations -28, -27, 27, 28) using the new reference subcarriers. If the received packet is identified as an HEW frame, then in decoding subsequent OFDM symbols, the HEW receiver will utilize positions -28, -27, 27, 28 in addition to the channel estimates obtained from the L-LTF. Channel estimation for subcarriers. The situation in which such extended channel estimates are made allows the HEW SIG-A to carry 56 data subcarrier allocations to date, as shown in Figure 6B. Assuming BPSK modulation and rate 1⁄2 write code (or QBPSK) for HEW SIG-A 408, this translates to an additional two information bits. The subcarriers at positions -28, -27, 27, and 28 are only used as examples, since the scope of the embodiments in this aspect is not limited.

In some other embodiments, the current L-LTF is a repetition of two long training sequences (LTS), and thus in a very low SNR scenario, the receiver can average the two LTSs to obtain a more reliable channel. estimate. To allow this same averaging in this recommendation for HEW, the explained subcarrier extension can also be applied to OFDM symbols directly followed by L-SIG. In a format such as the format shown in Figure 4, it will be the first OFDM symbol of HEW SIG-A1 408A. Therefore, in this example, the HEW SIG-A1 408A can Similar to VHT-SIG-A1 has 52 subcarriers. Both the L-SIG and SIG-A1 can use the new reference subcarriers (-28, -27, 27, 28) to calculate channel estimates. Subsequently, HEW SIG-A2 408B may have an additional four subcarriers for data distribution. In this case, HEW SIG-A1 and HEW SIG-A2 may have separate encoders/decoders, which are different from VHT-SIG-A1 and VHT-SIG-A2 with joint encoders/decoders.

Embodiments disclosed herein provide a method of increasing the number of subcarriers (e.g., increasing to 56) in a 20 MHz L-SIG. Because L-SIG is copied to support 40MHz bandwidth in 802.11n, and similar copying is supported in IEEE 802.11ac to support 80MHz and 160MHz, for 40, 80 and 160MHz, so L-SIG can be easily applied. Extension to 112, 224 and 448. The extended reference subcarriers may be used at the HEW receiver to obtain channel estimates in addition to the channel estimates obtained from the L-LTF. A channel estimate of 56 subcarriers is obtained compared to 52 subcarriers in IEEE 802.11n/11ac allowing 56 subcarriers to be utilized in subsequent OFDM symbols. Therefore, the four data subcarriers are added to the HEW SIG-A without additional burden. Because the focus on HEW is performance, organizations that increase the number of signaling bits without adding any additional burden are key to successful design and increase the chances of direct adoption in the standard.

FIG. 7 illustrates a HEW device in accordance with some embodiments. The HEW device 700 can be an HEW compliant device that can be arranged to communicate with one or more other HEW devices, such as the HEW station 104 (FIG. 1) or the primary station 102 (FIG. 1), and with legacy devices. HEW device 700 may be adapted to operate as primary station 102 (FIG. 1) or HEW station 104 (FIG. 1). According to an embodiment, the HEW device 700 In particular, hardware processing circuitry may be included, which may include a physical layer (PHY) circuit 702 and a medium access control layer circuit (MAC) 704. PHY 702 and MAC 704 may be HEW compliant layers and may also conform to one or more legacy IEEE 802.11 standards. The PHY 702 can be arranged to transmit HEW frames, such as HEW frames (Fig. 4). The HEW device 700 can also include other processing circuits 706 and memory 708 that are assembled to perform the various operations described herein.

According to some embodiments, the MAC 704 may be arranged to contend for the wireless medium during the contention period to receive a control over the media HEW control period and to group the HEW frames. The PHY 702 can be arranged to transmit the HEW frame as discussed above. The PHY 702 can also be arranged to receive HEW frames from the HEW station. The MAC 704 can also be arranged to transmit and receive operations via the PHY 702. PHY 702 may include circuitry for modulation/demodulation, upconversion/downconversion, filtering, amplification, and the like. In some embodiments, processing circuit 706 can include one or more processors. In some embodiments, two or more antennas may be coupled to a physical layer circuit that is arranged to transmit and receive signals, including transmitting HEW frames. Memory 708 can store information for use in assembly processing circuitry 706 for performing operations for assembling and transmitting HEW frames and performing the various operations described herein.

In some embodiments, HEW device 700 can be configured to communicate over a multi-carrier communication channel using OFDM communication signals. In some embodiments, HEW device 700 can be configured to receive signals in accordance with a particular communication standard, such as the Institute of Electrical and Electronics Engineers (IEEE) standards, including IEEE 802.11-2012, 802.11n-2009, and/or 802.11ac- 2013 standard, and/or recommended specifications for WLAN including the proposed HEW standard, although The scope of the invention in this aspect is not limited as it may also be suitable for transmitting and/or receiving communications in accordance with other technologies and standards. In some other embodiments, HEW device 700 can be configured to receive signals transmitted using one or more other modulation techniques, such as spread spectrum modulation (eg, direct sequence code division multiple access (DS-CDMA) And/or frequency hopping code division multiple access (FH-CDMA), time division multiplexing (TDM) modulation and/or frequency division multiplexing (FDM) modulation, although in this aspect the scope of the embodiment Unlimited.

In some embodiments, the HEW device 700 can be part of a portable wireless communication device, such as a personal digital assistant (PDA), a laptop or portable computer with wireless communication capabilities, a web tablet, a wireless telephone. Or smart phones, wireless headsets, pagers, instant messaging devices, digital cameras, access points, televisions, medical devices (eg heart rate monitors, blood pressure monitors, etc.) or other devices that can receive and/or transmit information wirelessly Device. In some embodiments, HEW device 700 can include one or more of the following: a keyboard, a display, a non-electric memory cartridge, a plurality of antennas, a graphics processor, an application processor, a speaker, and other mobile device components. The display can be an LCD screen including a touch screen.

The antenna of HEW device 700 may include one or more directional or omnidirectional antennas including, for example, dipole antennas, monopole antennas, block antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmission of RF signals. In some multiple input multiple output (MIMO) embodiments, the antennas can be effectively separated to take advantage of the spatial diversity and different channel characteristics that can occur between each of the antennas and the antennas of the transmitting stations.

Although the HEW device 700 is illustrated as having several separate functions Elements, but one or more of the functional elements may be combined and implemented by a combination of elements of the software, such as processing elements including a digital signal processor (DSP), and/or other hardware elements. For example, some components may include one or more microprocessors, DSPs, field programmable gate arrays (FPGAs), application specific collective circuits (ASICs), radio frequency collective circuits (RFICs), and at least for performing the functions described herein. A combination of various hardware and logic circuits. In some embodiments, the functional elements of HEW device 700 may involve operating one or more processes on one or more processing elements.

Embodiments can be implemented in one or a combination of hardware, firmware, and software. Embodiments can also be implemented as instructions stored on a computer readable storage device, which can be read and executed by at least one processor for performing the operations described herein. The computer readable storage device can include any non-transitory mechanism for storing information in a form readable by a machine (eg, a computer). For example, computer readable storage devices may include read only memory (ROM), random access memory (RAM), disk storage media, optical storage media, flash memory devices, and other storage devices and media. Some embodiments may include one or more processors and may be stored in an instruction stored on a computer readable storage device.

In some embodiments, the receiver of the HEW device can be arranged to receive a primary synchronization transmission during an initial portion of the HEW control period when the HEW device 700 is assembled to operate as the HEW station 104 (FIG. 1), the primary synchronization transmission including In a single multi-device HEW preamble, this single multi-device HEW preamble is arranged to signal and identify multiple data fields for multiple HEW stations 104 scheduled during the HEW control period. The receivers may also be grouped to receive one or more training fields (eg, the number of LTFs) received within the multi-device HEW preamble. To determine the initial channel estimate. The receiver may also be configured to receive the identified data field in the data field during the HEW control period and demodulate the data from the identified data field using the updated channel estimate.

In some embodiments, the primary station 102 can allocate resources to the scheduled HEW station 104 for use during the HEW control period based on criteria including one or more of the following: signal to noise ratio (SNR), configuration, throughput, The amount of data sent, the fairness criteria, and the quality of service requirements. The primary station 102 can determine whether the stations are the HEW station 104 or the legacy station 106 when combined with the primary station 102 via capability exchange. In some embodiments, the primary station 102 can notify the HEW station 104 that the control period will be used for communication in accordance with multiple access techniques. In some embodiments, the primary station 102 can use the control period in the presence of congestion and additionally communicate in accordance with conventional Wi-Fi technologies (eg, CSMA/CA). In some embodiments, the mapping of the control signals can be performed at the beginning of the transmission to list the devices that communicate during the control period, although the scope of the embodiments is not limited in this aspect.

FIG. 8 illustrates a procedure for HEW communication with increased information bits, in accordance with some embodiments. The process 800 can be performed by an access point that is configured to operate as a primary station, such as as a primary station 102 (FIG. 1) for HEW communication. In operation 802, the method may include assembling the HEW frame to include a legacy signal field (L-SIG), a HEW signal field followed by the L-SIG (HEW SIG-A), and a HEW SIG-A followed by Or multiple HEW fields. In operation 804, the method can include assembling the L-SIG 406 to use the old number of data subcarriers, the old number of pilot subcarriers, and a certain number of additional reference subcarriers modulated by a known reference sequence. transmission. In operation 806, the method can include assembling at least one symbol of the HEW SIG-A and the HEW frame One or more HEW fields followed by the HEW SIG-A to transmit using additional data subcarriers. The additional data subcarriers may correspond to additional reference subcarriers of the L-SIG. In operation 808, the method can include transmitting the assembled HEW frame. The frame can be transmitted during the HEW control period, and OFDMA communication can occur during the HEW control period.

In one example, the access points are grouped to operate as a primary station for high performance WLAN (HEW) communications. The access point includes a hardware processing circuit for assembling the HEW frame to include the legacy signal field (L-SIG), the HEW signal field (HEW SIG-A) followed by the L-SIG, and the HEW SIG-A. One or more HEW fields. In this example, the L-SIG is configured to transmit using the old number of data subcarriers, the old number of pilot subcarriers, and a certain number of additional reference subcarriers modulated by known reference sequences. In this example, at least one symbol of the HEW SIG-A and one or more HEW fields following the HEW SIG-A in the HEW frame are combined to transmit using additional data subcarriers, additional data subcarriers. An additional reference subcarrier corresponding to the L-SIG.

In another example, for a 20 MHz channel, the number of data subcarriers may be forty-eight, the number of pilot subcarriers may be four, and additional subcarriers modulated by known reference sequences. The number can be four, for a total of sixty-four subcarriers, including null subcarriers. In this example, the number of data subcarriers of the HEW data field followed by the HEW SIG-A is fifty-two.

In another example, the HEW frame further includes an old long training field (L-LTF) prior to the L-SIG. In this example, the hardware processing circuit It is configured to scale the full subcarrier power allocation of the L-SIG by a factor of 56/52.

In another example, for a 20 MHz channel, the pilot subcarriers are located at positions -21, -7, 7, 21 relative to the DC subcarriers, and the additional reference subcarriers are located relative to the DC subcarriers - 28, -27, 27, 28 places.

In another example, the known reference sequence modulated on the additional reference subcarriers of the L-SIG is used by the receiving HEW station for channel estimation to allow the receiving HEW station to demodulate and decode the additional HEW SIG-A. Data subcarriers and additional data subcarriers of one or more HEW fields followed by HEW SIG-A.

In another example, the hardware processing circuitry is configured to scale the full subcarrier power allocation of the L-SIG by a factor of B/A, where A is the old number of pilot subcarriers of the data subcarrier. There is a quantity, and B is the number of old quantity plus pilot subcarriers of the data subcarrier plus the number of additional subcarriers.

In another example, one or more HEW fields following the HEW SIG-A in the HEW frame include: HEW data fields; and HEW rows prior to scheduling information including one or more HEW stations The field field (HEW-SCH), which is scheduled to communicate with the access point during the data field according to the Scheduled Orthogonal Frequency Division Multiple Access (OFDMA) technique.

In another example, the HEW SIG-A includes at least a first symbol (HEW SIG-A1) and a second symbol (HEW SIG-A2). In this example, the information bits carried by the HEW SIG-A1 are mapped to the legacy data subcarriers, and the pilot subcarriers of the HEW SIG-A1 are mapped to the legacy pilot subcarriers. In this In the example, the additional reference subcarriers of HEW SIG-A1 are modulated by a known reference sequence. In this example, the information bits carried by the HEW SIG-A2 are mapped to the data subcarriers and the additional reference subcarriers. In this example, the pilot subcarriers of HEW SIG-A2 are mapped to legacy pilot subcarriers.

In another example, when the access point operates as a primary station, the access points can be configured to compete for wireless media during the contention period to receive control over the medium for the duration of the HEW control period; and during the HEW control period HEW, wherein during the HEW control period, the primary station has a mutually exclusive use of wireless media for communicating with the scheduled HEW station in accordance with a non-contention based multiple access technique.

In another example, when the access point operates as a primary station, the access point can be arranged to: transmit downlink data for each of the plurality of scheduled HEW stations transmitted during the HEW control period, from The downlink data of each scheduling station corresponds to one link and includes one or more streams; or uplink data received from multiple scheduled HEW stations for multiplex transmission in the HEW control period, from each The uplink data of a scheduled station corresponds to one link and includes one or more streams, and includes the number of LTFs in the LTF part of the HEW preamble; including the HEW scheduling field (HEW-SCH) Connected to the LTF section; and the HEW frame is assembled to include the old preamble prior to the HEW preamble.

In another example, the communication station is configured for high performance WLAN (HEW) communication, the station includes a hardware processing circuit that is configured to receive an HEW frame, the HEW frame including at least an old signal field (L) -SIG), HEW signal field (HEW SIG-A) followed by L-SIG and one followed by HEW SIG-A Or multiple HEW fields. In this example, the L-SIG uses the old number of data subcarriers, the old number of pilot subcarriers, and a certain number of additional reference subcarriers modulated by known reference sequences. In this example, at least one symbol of the HEW SIG-A and one or more HEW fields following the HEW SIG-A in the HEW frame are combined to transmit using additional data subcarriers, additional data subcarriers. An additional reference subcarrier corresponding to the L-SIG. In this example, the access point can decode the data subcarriers of the L-SIG to determine length and rate information, calculate channel estimates for additional reference subcarriers of the L-SIG from known reference sequences, and decode using channel estimates At least one symbol of the HEW SIG-A is an additional data subcarrier of one or more HEW fields followed by the HEW SIG-A.

In another example, the communication station can be further configured to avoid decoding additional reference subcarriers of the L-SIG.

In another example, the communication station is configured to decode the data subcarriers of the HEW SIG-A using channel estimates determined from the old training field, and the data subcarriers of the HEW SIG-A correspond to the data of the L-SIG. Carrier.

In another example, the communication station can be further configured to determine whether the received frame is an HEW frame or a legacy frame, based on whether the value in the length field of the L-SIG is divisible by three, or based on The phase rotation of the BPSK modulation of the first and second symbols of the subsequent signal field.

In another example, the HEW SIG-A includes at least a first symbol (HEW SIG-A1) and a second symbol (HEW SIG-A2). In this example, the information bits carried by the HEW SIG-A1 are mapped to the legacy data subcarriers, and the pilot subcarriers of the HEW SIG-A1 are mapped to the legacy pilot subcarriers. In this In the example, the additional reference subcarriers of HEW SIG-A1 are modulated by a known reference sequence. In this example, the information bits carried by the HEW SIG-A2 are mapped to the data subcarriers and the additional reference subcarriers. In this example, the pilot subcarriers of HEW SIG-A2 are mapped to legacy pilot subcarriers. In this example, the communication station is configured to utilize additional reference subcarriers of HEW SIG-A1 and additional reference subcarriers of the L-SIG for channel estimation; and based on self-L-LTF, L-SIG, and HEW SIG -A1 obtained channel estimate to decode HEW SIG-A2.

In another example, a method for high performance WLAN (HEW) communication includes: assembling an HEW frame to include a legacy signal field (L-SIG), and an HEW signal field followed by an L-SIG (HEW SIG- A) one or more HEW fields followed by HEW SIG-A; and wherein the L-SIG is configured to use the old number of data subcarriers, the old number of pilot subcarriers, and known references A certain number of additional reference subcarriers of the sequence modulation are transmitted, and wherein at least one symbol of the HEW SIG-A and one or more HEW fields following the HEW SIG-A in the HEW frame are combined to use an additional The data subcarriers are transmitted, and the additional data subcarriers correspond to additional reference subcarriers of the L-SIG.

In another example, for a 20 MHz channel, the number of data subcarriers is forty-eight, the number of pilot subcarriers is four, and the number of additional subcarriers modulated by a known reference sequence. There are four, a total of sixty-four subcarriers, including null subcarriers. In this example, the number of data subcarriers in the HEW data field followed by HEW SIG-A is fifty-two. One. In this example, for a 20 MHz channel, the pilot subcarriers are located at positions -21, -7, 7, 21 relative to the DC subcarriers, and the additional reference subcarriers are located at positions -28 relative to the DC subcarriers. , -27, 27, 28 places.

In another example, the known reference sequence modulated on the additional reference subcarriers of the L-SIG is used by the receiving HEW station for channel estimation to allow the receiving HEW station to demodulate and decode the additional HEW SIG-A. Data subcarriers and additional data subcarriers of one or more HEW fields followed by HEW SIG-A.

In another example, a non-transitory computer readable storage medium is provided that stores instructions for execution by one or more processors of an access point for operation for high performance WLAN (HEW) communication. In this example, the operation of the group access point is used to: assemble the HEW frame to include the legacy signal field (L-SIG), the HEW signal field (HEW SIG-A) followed by the L-SIG, and the HEW. One or more HEW fields followed by SIG-A. In this example, the L-SIG is configured to transmit using the old number of data subcarriers, the old number of pilot subcarriers, and a certain number of additional reference subcarriers modulated by known reference sequences. In this example, at least one symbol of the HEW SIG-A and one or more HEW fields following the HEW SIG-A in the HEW frame are combined to transmit using additional data subcarriers, additional data subcarriers. An additional reference subcarrier corresponding to the L-SIG.

In another example, the known reference sequence modulated on the additional reference subcarriers of the L-SIG is used by the receiving HEW station for channel estimation to allow the receiving HEW station to demodulate and decode the additional HEW SIG-A. Additional number of data subcarriers and one or more HEW fields followed by HEW SIG-A According to the subcarrier.

The Abstract is provided to comply with 37 C.F.R. Section 1.72(b), which requires the reader to determine an abstract of the nature and gist of the present disclosure. It should be understood that the abstract will not be used to limit or clarify the scope or meaning of the scope of the claims. The scope of the following patent application is hereby incorporated by reference in its entirety in its entirety in its entirety in its entirety herein

202‧‧‧Old Short Training Field (L-STF)

204‧‧‧Old Long Training Field (L-LTF)/L-LTF

400‧‧‧HEW frame

406‧‧ Old Signal Field (L-SIG)/L-SIG/Reference Subcarrier L-SIG

408‧‧‧HEW Signal Field (HEW SIG-A)/HEW SIG-A

408A‧‧‧First symbol (HEW SIG-A1)/HEW SIG-A1

408B‧‧‧Second symbol (HEW SIG-A2)

410‧‧‧HEW-STF

414‧‧‧HEW Scheduling Field (HEW-SCH)/HEW-SCH

416‧‧‧HEW data field/data field

Claims (22)

A wireless device configured to operate as a high performance (HE) station (HE-STA), the device comprising: a memory; and processing circuitry configured to: decode one of the HE data units Old-style signal field (L-SIG), the L-SIG includes four reference sub-carriers, which include two sub-carriers at each edge of a 20 MHz channel; and decoding the HE data unit An HE signal field (HE-SIG-A), the HE-SIG-A comprising a total number of data subcarriers including four of the four reference subcarriers corresponding to the L-SIG in frequency Data subcarriers, the four data subcarriers comprising two subcarriers at each edge of the 20 MHz channel, wherein the four reference subcarriers of the L-SIG are in addition to an old number of data subcarriers It is included in the L-SIG. The device of claim 1, wherein the HE data unit further comprises an old long training field (L-LTF) preceding the L-SIG, the L-LTF including the old number of reference subcarriers, and wherein The processing circuitry is further configured to decode the L-LTF prior to decoding the L-SIG. The device of claim 2, wherein for the 20 MHz channel, the number of the reference subcarriers of the L-LTF is forty-eight, The total number of data subcarriers included in the L-SIG is forty-eight, and the total number of data subcarriers included in the HE-SIG-A is fifty-two. The device of claim 3, wherein for the 20 MHz channel: the L-LTF includes four pilot subcarriers for a total of fifty two subcarriers and the forty eight reference subcarriers, the L-SIG including Four pilot subcarriers of fifty-six subcarriers, the forty eight data subcarriers, and the four reference subcarriers, and the HE-SIG-A further includes four pilots for a total of fifty-six subcarriers Frequency subcarriers and the fifty-two data subcarriers. The device of claim 3, wherein the processing circuit is configured to: determine the first channel estimate for the subcarrier frequency using the forty-eight reference subcarriers of the L-LTF, and use the L-SIG The four reference subcarriers determine a second channel estimate for the subcarrier frequency; and use the first and second channel estimates to demodulate the fifty-two of the HE-SIG-A Data subcarriers. The device of claim 2, wherein the four reference subcarriers of the L-SIG are modulated with a known reference sequence. The device of claim 2, wherein the L-SIG comprises one of the symbols modulated by a known BPSK cluster and a write rate. The device of claim 2, wherein the HE data unit receives a downlink HE data unit from a primary station, wherein the processing circuit is configured to receive in response to the downlink HE data unit For generating an uplink HE data unit, the uplink HE data unit is configured to include an L-SIG including one of the four reference subcarriers and one of the data subcarriers including the total number of HE- SIG-A, the total number of data subcarriers includes the four data subcarriers in the frequency corresponding to the four reference subcarriers of the L-SIG, and wherein the downlink HE data unit is received The processing is coupled to trigger the processing circuit to generate the uplink HE data unit for transmission to the primary station within a transmission opportunity (TXOP) obtained by the primary station. The device of claim 2, wherein the HE STA system is configured to operate as a primary station, wherein the HE data unit is uplinked by the primary station in response to transmission of the downlink HE data unit a link HE data unit, the downlink HE data unit being configured to include an L-SIG including one of the four reference subcarriers and one of the data subcarriers including the total number HE-SIG-A, The total number of data subcarriers includes the four data subcarriers in the frequency corresponding to the four reference subcarriers of the L-SIG, wherein the uplink HE data unit is obtained by the primary station Received within a transmission opportunity (TXOP), and The transmission of the downlink HE data unit is configured to trigger transmission of the uplink HE data unit to the primary station within the TXOP. The device of claim 1, wherein the HE data unit is received on a plurality of 20 MHz channels, wherein the processing circuit is further configured to: decode the L-SIG of the HE data unit, the L-SIG includes for each Four reference subcarriers of a 20 MHz channel, the four reference subcarriers comprising two subcarriers at each edge of each 20 MHz channel; and the HE-SIG- decoding of the HE data unit for each 20 MHz channel A. The HE-SIG-A includes the total number of data subcarriers including four data subcarriers in the frequency corresponding to the four reference subcarriers of the L-SIG. The device of claim 1, wherein the HE data unit further comprises a repetition of the L-SIG directly after the L-SIG and before the HE-SIG-A. The device of claim 1, further comprising a transceiver circuit coupled to the processing circuit, the transceiver circuit to receive the HE data on the 20 MHz channel. The device of claim 12, further comprising one or more antennas coupled to the transceiver circuit. A non-transitory computer readable storage medium storing instructions for use by a wireless device configured to operate as a High Efficiency (HE) Station (HE-STA) Execution of processing circuitry of the apparatus for assembling the wireless apparatus to operate to: decode an old signal field (L-SIG) of an HE data unit, the L-SIG including a known reference The four subcarriers of the sequence modulation, the four subcarriers, except for an old number of data subcarriers, comprising two subcarriers at each edge of a 20 MHz channel; and decoding the HE data One of the units HE signal field (HE-SIG-A), the HE-SIG-A comprising a total number of data subcarriers comprising four of the four subcarriers corresponding to the L-SIG in frequency Data subcarriers, the four data subcarriers comprising two subcarriers at each edge of the 20 MHz channel. The non-transitory computer readable storage medium of claim 14, wherein the HE data unit further comprises an old long training field (L-LTF) prior to the L-SIG, the L-LTF including the old quantity The reference subcarriers, and wherein the processing circuitry is further configured to decode the L-LTF prior to decoding the L-SIG. The non-transitory computer readable storage medium of claim 15, wherein for the 20 MHz channel: the old number of reference subcarriers of the L-LTF is forty-eight, and is included in a data subcarrier in the L-SIG The total number is forty-eight, and The total number of data subcarriers included in the HE-SIG-A is fifty-two. A wireless device configured to operate as a high performance (HE) station (HE-STA), the device comprising: a memory; and processing circuitry to generate one of transmissions for use on a 20 MHz channel An HE data unit, the HE data unit comprising a plurality of fields, wherein the HE data unit is to be generated, the processing circuit is configured to: encode an old long training field (L-LTF) of the HE data unit, The L-LTF includes an old number of reference subcarriers; encodes an old signal field (L-SIG) of the HE data unit, the L-SIG is followed by the L-LTF, and the L-SIG contains four references. a subcarrier and an old number of data subcarriers, the four reference subcarriers comprising two subcarriers at each edge of the 20 MHz channel; encoding one HE signal field of the HE data unit (HE-SIG-A) The HE-SIG-A includes a total number of data subcarriers including four data subcarriers corresponding to the four reference subcarriers of the L-SIG in frequency; and for the 20 MHz channel The transmission of the L-SIG and the HE-SIG-A is coordinated with one of the sub-carrier power allocations of the L-SIG and the HE-SIG-A. The L-SIG has the same total power as the L-LTF and the HE-SIG-A and the L-LTF have the same total power. The device of claim 17, further comprising a transceiver circuit configured to transmit the HE data unit, the HE data unit including the L-LTF on the each of the plurality of 20 MHz channels, the L-SIG And the HE-SIG-A: wherein the L-LTF, the L-SIG, and the HE-SIG-A are each configured to be transmitted at the same total power. The device of claim 18, wherein the processing circuit is configured to: scale the L-SIG by a ratio of the old number of subcarriers of the L-LTF to a total number of subcarriers of the L-SIG The subcarrier power allocation of each of the subcarriers, and the HE of the total number of subcarriers of the L-LTF to a total number of subcarriers of the HE-SIG-A - Subcarrier power allocation for each of the subcarriers of SIG-A. The device of claim 18, wherein the HE data unit is configured to request a response by a plurality of HE STAs, the response to include an uplink in a TXOP on at least one of the plurality of 20 MHz channels Data unit transmission, the uplink data unit transmission comprising HE data units, the HE data unit comprising an L-SIG having the four reference subcarriers and a HE-SIG having the total number of data subcarriers A. The device of claim 20, wherein for each 20 MHz channel: the old number of reference subcarriers of the L-LTF is forty-eight, and the total number of data subcarriers included in the L-SIG is Forty-eight, and the total number of data subcarriers included in the HE-SIG-A is fifty-two. A wireless device configured to operate as a high performance (HE) station (HE-STA), the device comprising: a memory; and processing circuitry configured to: decode one of the data units for training a first signal field of the training field of the data unit, the first signal field includes four reference subcarriers and a plurality of data subcarriers, and the four reference subcarriers include Two subcarriers at each edge of a 20 MHz channel; and decoding a second signal field of the data unit, the second signal field comprising a total number of data subcarriers, including in frequency corresponding to the Four data subcarriers of the four reference subcarriers of the first signal field, wherein a channel estimation value of the four reference subcarriers based on the first signal field is used to decode the second signal field The four data subcarriers corresponding to the bits, and one of the channel estimates based on the reference subcarriers of the training field, are used to decode the data subcarriers of the first signal field and the second signal field Corresponding data subload .