CN106664275A

CN106664275A - Physical layer frame format for WLAN

Info

Publication number: CN106664275A
Application number: CN201580010085.4A
Authority: CN
Inventors: 张鸿远; 徐明光; 孙亚崑
Original assignee: Mawier International Trade Co Ltd
Current assignee: Kaiwei International Co; Marvell International Ltd; Marvell Asia Pte Ltd
Priority date: 2014-01-07
Filing date: 2015-01-07
Publication date: 2017-05-10
Anticipated expiration: 2035-01-07
Also published as: JP2017510111A; CN106664275B; KR20160106123A; EP3092759A1; WO2015105875A1; JP6464494B2; KR102376949B1

Abstract

In a method for generating a physical layer (PHY) data unit for transmission via a communication channel, the PHY data unit conforming to a first communication protocol, a first communication device generates a PHY preamble for the PHY data unit, including: generating a signal field, including the signal field and a duplicate of the signal field in the PHY preamble, and formatting the PHY preamble such that a first portion of the PHY preamble is decodable by a second communication device that conforms to a second communication protocol, but does not conform to the first communication protocol, to determine a duration of the PHY data unit based on the first portion of the PHY preamble. The first communication device generates the PHY data unit to include the PHY preamble and a PHY payload.

Description

For the physical layer frame form of WLAN

Cross-Reference to Related Applications

The disclosure is the of entitled " the Range Extension Mode for WiFi " that submit on October 24th, 2014 The part continuation application of 14/523, No. 678 U.S. Patent application, it requires the entitled " Range submitted on October 25th, 2013 No. 61/895,591 U.S. Provisional Patent Application of Extension PHY ", the entitled " Range submitted on January 9th, 2014 No. 61/925,332 U.S. Provisional Patent Application of Extension PHY ", on March 10th, 2014 submit to it is entitled No. 61/950,727 U.S. Provisional Patent Application of " Range Extension PHY " and the topic submitted on May 2nd, 2014 For the rights and interests of the 61/987th, No. 778 U.S. Provisional Patent Application of " Range Extension PHY ", the entire disclosure It is incorporated herein by with entire content.

Additionally, the disclosure requires entitled " the Physical Layer Frame Format submitted on January 7th, 2014 No. 61/924,467 U.S. Provisional Patent Application of for WLAN ", the entitled " Physical submitted on July 29th, 2014 No. 62/030,426 U.S. Provisional Patent Application of Layer Frame Format for WLAN ", carry within 7th in August in 2014 No. 62/034,509 US provisional patent Shen of entitled " the Physical Layer Frame Format for WLAN " that hand over Please, the 62/045th of entitled " the Physical Layer Frame Format for WLAN " submitted to for 3rd in September in 2014, No. 363 U.S. Provisional Patent Applications, entitled " the Physical Layer Frame Format submitted to for 17th in September in 2014 No. 62/051,537 U.S. Provisional Patent Application of for WLAN " and the entitled " Physical submitted on December 8th, 2014 The rights and interests of the 62/089th, No. 032 U.S. Provisional Patent Application of Layer Frame Format for WLAN ", its entire disclosure Content is incorporated herein by with entire content.

Technical field

The disclosure relates generally to cordless communication network, and relates more particularly to promote and leaving in WLAN (legacy) physical layer (PHY) frame format of coexistence.

Background technology

When operation in infrastructure mode when, WLAN (WLAN) generally include access point (AP) and one or more Client stations.WLAN was developed rapidly in past ten years.Wlan standard (such as institute of electrical and electronic engineers (IEEE) 802.11a, 802.11b, 802.11g and 802.11n standard) research and development improve single user peak-data handling capacity.For example, IEEE 802.11b standards specify the single user peak throughput of 11 MBPSs (Mbps), IEEE 802.11a and 802.11g standards specify the single user peak throughput of 54Mbps, and IEEE 802.11n standards specify the single user peak of 600Mbps Value handling capacity, and IEEE 802.11ac standards specify the single user peak throughput in the range of Gigabits per second (Gbps).Not The standard come makes a promise to provide even more big handling capacity, the handling capacity in the range of such as tens Gbps.

The content of the invention

In embodiment, a kind of method is for generating physical layer (PHY) data cell for via the biography of communication channel Defeated, PHY data unit meets the first communication protocol.The method is included at the first communication equipment and generates for PHY data unit PHY it is leading, including：Generate signal field, by the duplication of signal field and signal field be included in PHY it is leading in, it is and right PHY is leading to be formatted so that PHY leading Part I is by meeting the second communication protocol but do not meet the first communication protocol The second communication equipment decodable code, to be based on the leading Part I of PHY determining the duration of PHY data unit.Should Method is additionally included at the first communication equipment and generates PHY data unit with including PHY is leading and PHY payload.

In various other embodiments, the method is also including or any in two or more in following characteristics Suitable combination.

Signal field is to leave signal field by the second communication equipment is decodable；Leave signal field and be included in PHY In leading Part I；And leave information of the signal field comprising the duration for indicating PHY data unit.

Generate that the PHY for PHY data unit is leading also to be included：Generation meets the other signal letters of the second communication protocol Section, and other signal field is included in the leading Part II of PHY.

PHY leading Part II is that the second communication equipment is un-decodable.

Generate that the PHY for PHY data unit is leading also to be included：The duplication of other signal field is included in before PHY In the Part II led.

Signal field is the first signal field；And generate that the PHY for PHY data unit is leading also to be included：Generate by The decodable secondary signal field of second communication equipment, wherein, secondary signal field include indicate PHY data unit it is lasting when Between information, including the secondary signal field in the leading Part I of PHY, and including in PHY leading Part II First signal field.

PHY leading Part II is that the second communication equipment is un-decodable.

PHY for PHY data unit leading is generated with the orthogonal frequency domain (OFDM) in PHY leading Part I Corresponding first protection interval is included between symbol；And the method is additionally included in generation PHY payload at the first communication equipment With between the OFDM symbol of PHY payload include corresponding second protection interval, wherein each second protection interval have than Each the first protection interval longer duration.

For PHY data unit PHY it is leading be generated between the OFDM symbol in PHY leading Part II wrap Containing corresponding second protection interval.

In another embodiment, the first communication equipment includes the Network Interface Unit with one or more integrated circuits, One or more integrated circuits are configured to：Generate the PHY for meeting physical layer (PHY) data cell of the first communication protocol It is leading, including：Generate signal field, by the duplication of the signal field of signal field sum be included in PHY it is leading in, and format PHY is leading so that PHY leading Part I by meet the second communication protocol but do not meet the first communication protocol second communication Equipment decodable code, to be based on the leading Part I of PHY determining the duration of PHY data unit.One or more collection It is additionally configured into circuit：PHY data unit is generated with leading and PHY payload comprising PHY.

In various other embodiments, the first communication equipment is also including in two or more in following characteristics Or any suitable combination.

Signal field is to leave signal field by the second communication equipment is decodable；One or more integrated circuits are configured For：Signal field will be left including in PHY leading Part I；And signal field is left comprising instruction PHY data unit Duration information.

One or more integrated circuits are configured to：Generation meets the other signal field of the second communication protocol, and Other signal field is included in the leading Part II of PHY.

PHY leading Part II is that the second communication equipment is un-decodable.

One or more integrated circuits are configured to：The duplication of other signal field is included in into PHY leading second In part.

Signal field is the first signal field；And one or more integrated circuits are configured to：Generate by the second communication The information of the decodable secondary signal field of equipment, wherein secondary signal field comprising the duration for indicating PHY data unit, Secondary signal field is included in the leading Part I of PHY, and the first signal field is included in into leading second of PHY In part.

PHY leading Part II is that the second communication equipment is un-decodable.

One or more integrated circuits are configured to：Generate leading with leading in PHY for the PHY of PHY data unit Corresponding first protection interval is included between orthogonal frequency domain (OFDM) symbol in Part I；And generate PHY payload with Between OFDM symbol in PHY payload include corresponding second protection interval, wherein each second protection interval have than Each the first protection interval longer duration.

One or more integrated circuits are configured to：Generate PHY leading with the Part II leading including PHY Corresponding second protection interval is included between OFDM symbol.

Description of the drawings

Fig. 1 is the block diagram of the example wireless local area network (WLAN) according to embodiment.

Fig. 2A and Fig. 2 B are the diagrams of prior art data unit format.

Fig. 3 is the diagram of another prior art data unit format.

Fig. 4 is the diagram of another prior art data unit format.

Fig. 5 is the diagram of another prior art data unit format.

Fig. 6 A are one group of diagrams for modulating the modulation that the symbol in prior art data cell is used.

Fig. 6 B are one group of diagrams of the modulation that the symbol in the modulation example data cell according to embodiment is used.

Fig. 7 A are the diagrams of OFDM (OFDM) data cell according to embodiment.

Fig. 7 B are the one of the modulation that the symbol in the data cell described in modulation Fig. 7 A according to embodiment is used Group diagram.

Fig. 8 is the block diagram of the OFDM symbol according to embodiment.

Fig. 9 A are the leading sample datas that data cell is used for according to the wherein conventional encoding scheme of diagram of embodiment The diagram of unit.

Fig. 9 B are the leading only a parts that data cell is used for according to the wherein conventional encoding scheme of diagram of embodiment Exemplary data cells diagram.

Figure 10 A are to illustrate the exemplary data cells that its medium pitch spacing is adjusted and block coded combination is used according to embodiment Diagram.

Figure 10 B are to illustrate the sample data that its medium pitch spacing is adjusted and block coded combination is used according to another embodiment The diagram of unit.

Figure 11 A are the diagrams of the diagram normal mode data cell according to embodiment.

Figure 11 B are the diagrams of the diagram scope mode of extension data cell according to embodiment.

Figure 12 A- Figure 12 B are showing for the two possible forms for illustrating long training field respectively according to two example embodiments Figure.

Figure 13 A are the diagrams of the non-legacy signal field of the normal mode data cell of pictorial image 11A according to embodiment.

Figure 13 B are the non-legacy signal fields of the scope mode of extension data cell of pictorial image 11B according to embodiment Diagram.

Figure 14 A are the block diagrams of the diagram scope mode of extension data cell according to embodiment.

Figure 14 B are that the scope mode of extension data cell of pictorial image 14A according to one embodiment leaves signal field Diagram.

Figure 14 C are that the leaving in quick Fu of signal field of Figure 14 B at receiving device is left according to the diagram of embodiment The diagram of leaf transformation (FFT) window.

Figure 15 is the block diagram of the form of the diagram non-legacy signal field according to embodiment.

Figure 16 is to be used to generate the example of normal mode data cell using conventional encoding scheme according to the diagram of embodiment The block diagram of PHY processing units.

Figure 17 A are for use range extended coding schemes generation scope mode of extension data cell according to embodiment The block diagram of example PHY processing unit.

Figure 17 B are the example PHY processing units for formation range mode of extension data cell according to another embodiment Block diagram.

Figure 18 A are for use range extended coding schemes generation scope mode of extension data sheet according to another embodiment The block diagram of the example PHY processing unit of unit.

Figure 18 B are the example PHY processing units for formation range mode of extension data cell according to another embodiment Block diagram.

Figure 19 A are the example PHY processing units for formation range mode of extension data cell according to another embodiment Block diagram.

Figure 19 B are the example PHY processing units for formation range mode of extension data cell according to another embodiment Block diagram.

Figure 20 A be according to embodiment illustrate scope mode of extension data cell it is leading in OFDM symbol repetition Diagram.

Figure 20 B be according to embodiment illustrate scope mode of extension data cell it is leading in OFDM symbol repetition Diagram.

Figure 20 C are the diagrams for illustrating the time domain iteration scheme for OFDM symbol according to one embodiment.

Figure 20 D are the diagrams for illustrating the iteration scheme for OFDM symbol according to another embodiment.

Figure 21 is the flow chart for generating the exemplary method of data cell according to embodiment.

Figure 22 A are the diagrams of the 20MHz total bandwidths of the repetition with scope growth data unit according to embodiment, wherein Scope growth data unit has 10MHz sub-bands.

Figure 22 B are the diagrams of the 40MHz total bandwidths of the repetition with scope growth data unit according to embodiment, wherein Scope growth data unit has 10MHz sub-bands.

Figure 22 C are the diagrams planned according to the example tone for 32-FFT patterns of embodiment.

Figure 23 is the leading exemplary data cells that data cell is used for according to the wherein scope mode of extension of embodiment Diagram.

Figure 24 is the example PHY processing unit for formation range mode of extension data cell according to another embodiment Block diagram.

Figure 25 A are the diagrams of the example 20MHz total bandwidth with 1/2 tone spacing according to embodiment.

Figure 25 B are the diagrams of the example 20MHz total bandwidth with 1/2 tone spacing according to embodiment.

Figure 26 A are the non-something lost for the scope mode of extension with the tone spacing of FFT sizes 64 and 1/2 according to embodiment The diagram for staying tone to plan.

Figure 26 B are for the non-of the scope mode of extension with the tone spacing of FFT sizes 128 and 1/2 according to embodiment Leave the diagram of tone planning.

Figure 26 C are for the non-of the scope mode of extension with the tone spacing of FFT sizes 256 and 1/2 according to embodiment Leave the diagram of tone planning.

Figure 27 is the flow chart for generating the exemplary method of data cell according to embodiment.

Figure 28 is the flow chart for generating the exemplary method of data cell according to another embodiment.

Figure 29 is to meet the first communication protocol compared with the leading part for meeting legacy protocol, according to embodiment The leading part of example PHY diagram.

Figure 30 is to meet the first communication compared with the leading part for meeting legacy protocol, according to another embodiment The diagram of the leading part of another example PHY of agreement.

Figure 31 is to meet the first communication compared with the leading part for meeting legacy protocol, according to another embodiment The diagram of the leading part of another example PHY of agreement.

Figure 32 is to meet the first communication compared with the leading part for meeting legacy protocol, according to another embodiment The diagram of the leading part of another example PHY of agreement.

Figure 33 is to meet the first communication compared with the leading part for meeting legacy protocol, according to another embodiment The diagram of the leading part of another example PHY of agreement.

Figure 34 is to meet the first communication compared with the leading part for meeting legacy protocol, according to another embodiment The diagram of the leading part of another example PHY of agreement.

Figure 35 is to meet the first communication compared with the leading part for meeting legacy protocol, according to another embodiment The diagram of the leading part of another example PHY of agreement.

Figure 36 is to meet the first communication according to another embodiment compared with the leading part for meeting legacy protocol The diagram of the leading part of another example PHY of agreement.

Figure 37 is to meet the first communication compared with the leading part for meeting legacy protocol, according to another embodiment The diagram of the leading part of another example PHY of agreement.

Figure 38 A-D are according to the leading automatic detection symbol for utilizing of the diagram of various embodiments and example PHY of Figure 37 The diagram of example.

Figure 39 is to meet the first communication compared with the leading part for meeting legacy protocol, according to another embodiment The diagram of the leading part of another example PHY of agreement.

Figure 40 A are showing according to the leading part of another example PHY for meeting the first communication protocol of another embodiment Figure.

Figure 40 B are showing according to the leading part of another example PHY for meeting the first communication protocol of another embodiment Figure.

Figure 41 is to meet the first communication protocol compared with the leading part for meeting legacy protocol according to embodiment Scope mode of extension the leading part of another example PHY diagram and meet the first communication protocol normal mode it is another The diagram of the leading part of one example PHY.

Figure 42 is to meet the first communication protocol compared with the leading part for meeting legacy protocol according to embodiment Scope mode of extension the leading part of another example PHY diagram and meet the first communication protocol normal mode it is another The diagram of the leading part of one example PHY.

Figure 43 is to meet the first communication protocol compared with the leading part for meeting legacy protocol according to embodiment Scope mode of extension the leading part of another example PHY diagram and meet the first communication protocol normal mode it is another The diagram of the leading part of one example PHY.

Specific embodiment

In the embodiments described below, Wireless Communication Equipment (access point (AP) of such as WLAN (WLAN)) To one or more client stations transmission data flows.AP is configured to be operated with client stations according at least the first communication protocol. First communication protocol is referred to herein as " high efficiency Wi-Fi ", " HEW " communication protocol or 802.11ax communication protocols sometimes. In certain embodiments, the different clients station near AP is configured to according to one or more other communication protocol operations, this A little communication protocol definitions with HEW communication protocol same frequency bands in but with the operation of generally relatively low data throughout.It is relatively low Data throughout communication protocol (for example, IEEE 802.11a, IEEE 802.11n and/or IEEE 802.11ac) herein In be referred to as " leaving " communication protocol.In at least some embodiments, legacy communication protocols are generally deployed in indoor communications channel In, and HEW communication protocols at least when be deployed for the signal to noise ratio of outdoor communication, the communication of spreading range or sending signal (SNR) communication in the region for reducing.

According to embodiment, the symbol sent by AP is generated according to scope extended coding scheme, and scope extension is compiled Code scheme provides the redundancy of the increase of the information bit of symbol or coding in symbol.Redundancy increased symbol by receiving from AP Symbol the possibility that is successfully decoded of equipment, especially in the region that SNR is reduced.Mitigate the redundancy required for SNR is reduced Amount generally depend on time delay channel spread (for example, for outdoor communication channel), interference symbol other signals and/or other Factor.In embodiment, HEW communication protocol definitions normal mode and scope mode of extension.In embodiment, normal mode is general Ground with by the communication channel for compared with short channel time delay spread (for example, indoor communications channel) or generally being characterized compared with high snr values together Use, and scope mode of extension typically with by relatively long channel delay spread (for example, outdoor communication channel) or by generally compared with The communication channel that low SNR value is characterized is used together.In embodiment, conventional encoding scheme is used in normal mode, and Scope extended coding scheme is used in scope mode of extension.

In embodiment, the data cell sent by AP includes leading and data division, wherein, it is leading at least in part Be used to for the various parameters of the transmission for data division to be signaled to receiving device.In various embodiments, data Unit it is leading be used to be signaled to the specific coding scheme utilized at least data division of data cell connect Receiving unit.In certain embodiments, use in normal mode with the leading form of identical in scope mode of extension.At one It is leading including being set to indicate that conventional encoding scheme or scope extended coding scheme be used for data in such embodiment The instruction of at least data division of unit.In certain embodiments, in addition to the data division of data cell, indicated conventional volume Code scheme or scope extended coding scheme are used for leading at least a portion of data cell.In embodiment, receiving device Based on data cell it is leading in instruction determining the specific coding scheme that will be utilized, and and then use specific coding scheme The appropriate remainder (for example, data division or a leading and data division part) of decoding data unit.

In another embodiment, use is leading leading by not in normal mode with use in scope mode of extension Format together.For example, to being formatted using leading in scope mode of extension so that receiving device can be automatically (for example, before decoding) detection data unit is corresponding with scope mode of extension.In embodiment, when receiving device is detected When data cell is corresponding with scope mode of extension, receiving device use range extended coding scheme is by the data portion of data cell Divide and the data division of leading at least some embodiments at least a portion and data cell is decoded.On the other hand, exist In embodiment, when receiving device detect data cell it is not corresponding with scope mode of extension when, receiving device assume data sheet Unit is corresponding with normal mode.Receiving device and then at least data division using conventional encoding scheme decoding data unit.

Additionally, at least some embodiments, to the leading of the data cell in normal mode and/or scope mode of extension It is formatted so that can determine with regard to data cell according to the client stations of legacy protocol rather than HEW communication protocol operations Some information (duration of such as data cell) and/or data cell do not meet legacy protocol.Additionally, in embodiment, The leading of data cell is formatted so that can determine that data cell meets HEW according to the client stations of HEW agreements operation Whether communication protocol and data cell format according to normal mode or scope mode of extension.Similarly, in embodiment, quilt It is configured to also send all data cells as described above according to the client stations of HEW communication protocol operations.

In at least some embodiments, for example, for being configured to be operated according to multiple different communication protocols and client stations AP and/or for the WLAN that plurality of client stations are operated according to multiple different communication protocols, it is all as described above The data cell of formatting be useful.Continue example above, be configured to according to HEW communication protocols (including normal mode With scope mode of extension) and the communication equipment of operation can determine that data-oriented unit is according to HEW both legacy communication protocols What communication protocol rather than legacy communication protocols were formatted, and also determine that data cell is unconventional according to scope mode of extension Schema formatting.Similarly, being configured to can according to the communication equipment of legacy communication protocols rather than HEW communication protocol operations Determine that data cell formats and/or determine the duration of data cell not according to legacy communication protocols.

Fig. 1 is that the block diagram .AP 14 of the example wireless local area network (WLAN) 10 according to embodiment includes being coupled to network interface 16 host-processor 15.Network interface 16 includes that medium access control (MAC) processing unit 18 and physical layer (PHY) process single Unit 20.PHY processing units 20 include multiple transceivers 21, and transceiver 21 is coupled to multiple antennas 24.Although scheming in FIG Show three transceivers 21 and three antennas 24, but in other embodiments, (for example, 1, AP 14 includes other suitable numbers 2nd, 4,5 etc.) transceiver 21 and antenna 24.In one embodiment, MAC processing units 18 and PHY processing units 20 are matched somebody with somebody It is set to and is operated according to the first communication protocol (for example, HEW communication protocols), at least the first mode including the first communication protocol and the Two modes.In certain embodiments, first mode is corresponding with scope mode of extension, its use range extended coding scheme (example Such as, block coding, step-by-step duplication or symbol are replicated), signal modulation scheme (for example, phase-shift keying (PSK) or quadrature amplitude modulation) or scope Both extended coding scheme and signal modulation scheme.With at which perform meet scope mode of extension PHY data unit into The second mode (for example, using the normal mode of conventional encoding scheme) of work(decoding compares, and scope mode of extension is configured to Increase scope and/or reduce signal to noise ratio (SNR).In various embodiments, compared with normal mode, scope mode of extension is reduced Transmitted data rates are successfully decoded with the SNR ratios for realizing having increased scope and/or reduction.In another embodiment, MAC Processing unit 18 and PHY processing units 20 are additionally configured to be grasped according to the second communication protocol (for example, IEEE 802.11ac standards) Make.In another embodiment, MAC processing units 18 and PHY processing units 20 be additionally configured as according to the second communication protocol, Third communication agreement and/or fourth communication agreement (for example, IEEE 802.11a standards and/or IEEE 802.11n standards) are grasped Make.

WLAN 10 includes multiple client stations 25.Although four client stations 25 are illustrated in FIG, in various scenes In embodiment, WLAN 10 includes the client stations 25 of other suitable numbers (for example, 1,2,3,5,6 etc.).In client stations 25 At least one (for example, client stations 25-1) is configured to according at least to the first communication protocol operations.In certain embodiments, client Stand and at least one of 25 be not adapted to according to the first communication protocol operations, but be configured as according to the second communication protocol, At least one of third communication agreement and/or fourth communication agreement (referred to herein as " leaving client stations ") are operated.

Client stations 25-1 includes being coupled to the host-processor 26 of network interface 27.It is single that network interface 27 includes that MAC is processed First 28 and PHY processing units 29.PHY processing units 29 include multiple transceivers 30, and transceiver 30 is coupled to multiple antennas 34.Although illustrating three transceivers 30 and three antennas 34, in other embodiments, client stations 25-1 bags in FIG Include the transceiver 30 and antenna 34 of other suitable numbers (for example, 1,2,4,5 etc.).

According to embodiment, client stations 25-4 is to leave client stations, i.e. client stations 25-4 is not supported according to the first communication protocol Receive and fully decode the data cell sent by AP 14 or another client stations 25.Similarly, according to embodiment, leave Client stations 25-4 does not support to send data cell according to the first communication protocol.On the other hand, leave client stations 25-4 and support basis Second communication protocol, third communication agreement and/or fourth communication agreement are received, fully decode and send data cell.

In embodiment, one or both of client stations 25-2 and 25-3 have and the same or similar knots of client stations 25-1 Structure.In embodiment, client stations 25-4 has the structure similar with client stations 25-1.In these embodiments, with client stations 25- 1 same or similar structurized client stations 25 have the transceiver and antenna of identical or different number.For example, according to enforcement Example, client stations 25-2 only has two transceivers and two antenna (not shown).

In various embodiments, the PHY processing units 20 of AP 14 are configurable to generate and meet the first communication protocol and have There is the data cell of form described herein.(one or more) transceiver 21 is configured to via (one or more) antenna 24 send generated data cell.Similarly, (one or more) transceiver 21 is configured to via (one or more) day The receiving data unit of line 24.According to various embodiments, the PHY processing units 20 of AP 14 are configured to process and meet the first communication Agreement and the received data unit with the form being described below and the such data cell of determination meet First communication protocol.

In various embodiments, the PHY processing units 29 of client device 25-1 are configurable to generate and meet the first communication Agreement and with the data cell of form described herein.(one or more) transceiver 30 is configured to via (one Or multiple) the generated data cell of the transmission of antenna 34.Similarly, (one or more) transceiver 30 is configured to via (one It is individual or multiple) the receiving data unit of antenna 34.According to various embodiments, the PHY processing units 29 of client device 25-1 are matched somebody with somebody It is set to process and meets the first communication protocol and the received data unit with the form being described below and really Fixed such data cell meets the first communication protocol.

Fig. 2A is to be configured to be modulated to leaving client stations via OFDM (OFDM) according to the AP 14 of embodiment The diagram of the prior art OFDM data unit 200 that 25-4 sends.In embodiment, leave client stations 25-4 be additionally configured to by Data cell 200 is sent to AP 14.Data cell 200 meets IEEE 802.11a standards and occupies 20 megahertzs (MHz) frequency Band.Data cell 200 includes having to be left short training field (L-STF) 202 and (is commonly used to interblock interference, initial synchronisation With automatic growth control etc.) and leave long training field (L-LTF) 204 (being commonly used to channel estimation and fine synchronization) It is leading.Data cell 200 also includes leaving letter with regard to some physical layer (PHY) parameters of data cell 200 for carrying Number field (L-SIG) 206, such as sends modulation type and code rate that data cell is used.Data cell 200 is also Including data division 208.Fig. 2 B are (without low-density checksum coding) diagrams of sample data part 208, if its Then include service field, the physical layer service data (PSDU) of Jing scramblers, tail bits and filling bit if needs. Data cell 200 be designed to a spatial flow in single-input single-output (SISO) channel configuration or space-time stream it On transmission.

Fig. 3 is to be configured to be modulated to leaving client stations via orthogonal frequency domain multiplexing (OFDM) according to the AP 14 of embodiment The diagram of the prior art OFDM data unit 300 that 25-4 sends.In embodiment, leave client stations 25-4 be additionally configured to by Data cell 300 is sent to AP 14.Data cell 300 meets IEEE 802.11n standards, occupies 20MHz frequency bands and set Count for mixed mode situation, i.e. when WLAN includes meeting the one of IEEE 802.11a standards rather than IEEE 802.11n standards During individual or multiple client stations.Data cell 300 include it is leading, there is L-STF 302, L-LTF 304, L-SIG 306, height to gulp down for it The amount of telling signal field (HT-SIG) 308, high-throughput short training field (HT-STF) 310 and M data high-throughput length training Field (HT-LTF) 312, wherein, M is general by transmission data cell 300 institute in multiple-input and multiple-output (MIMO) channel configuration Integer determined by the number of the spatial flow for using.Especially, according to IEEE 802.11n standards, if data cell 300 makes Two spaces streaming is used, then data cell 300 includes two HT-LTF 312；If data cell 300 uses three or four Individual space streaming, then data cell 300 include four HT-LTF 312.The certain number of instruction quilt of the spatial flow for being utilized In being included in HT-SIG fields 308.Data cell 300 also includes data division 314.

Fig. 4 is to be configured to be modulated to leaving client stations via orthogonal frequency domain multiplexing (OFDM) according to the AP 14 of embodiment The diagram of the prior art OFDM data unit 400 that 25-4 sends.In embodiment, leave client stations 25-4 be additionally configured to by Data cell 400 is sent to AP 14.Data cell 400 meets IEEE 802.11n standards, occupies 20MHz frequency bands and set Count for " patterns of green area " situation, i.e. when WLAN does not include meeting any client stations of IEEE 802.11a standards and only wrapping Include the client stations for meeting IEEE 802.11n standards.Data cell 400 include it is leading, it has high-throughput patterns of green area short training The 402, first high-throughput long training field of section of practising handwriting (HT-GF-STF) (HT-LTF1) 404, HT-SIG 406 and M data HT-LTF 408, wherein, M is typically to be used with the transmission data cell 400 in multiple-input and multiple-output (MIMO) channel configuration Spatial flow the corresponding integer of number.Data cell 400 also includes data division 410.

Fig. 5 is to be configured to be modulated to leaving client stations via orthogonal frequency domain multiplexing (OFDM) according to the AP 14 of embodiment The diagram of the prior art OFDM data unit 500 that 25-4 sends.In embodiment, leave client stations 25-4 be additionally configured to by Data cell 500 is sent to AP 14.Data cell 500 meets IEEE 802.11ac standards and is designed to " mixing word Section " situation.Data cell 500 occupies 20MHz bandwidth.In other embodiment or scene, the data similar with data cell 500 Unit occupies different bandwidth, such as 40MHz, 80MHz or 160MHz bandwidth.Data cell 500 include it is leading, it has L- STF 502, L-LTF 504, L-SIG 506, including the first very high throughput signal field (VHT-SIGA1) 508-1 and The two first very high throughput signal field (VHT- of two very high throughput signal field (VHT-SIGA2) 508-2 SIGA) 508, very high-throughput short training field (VHT-LTF) 510, M individual very (its of high-throughput long training field 512 In, M is integer) and the second unusual high throughput signal field (VHT-SIG-B) 514.Data cell 500 also includes data portion Divide 516.

Fig. 6 A are illustrated such as L-SIG, HT-SIG1 of the data cell 300 of Fig. 3 by defined in IEEE 802.11n standards With one group of diagram of the modulation of HT-SIG2 fields.L-SIG fields are modulated according to binary phase shift keying (BPSK), and HT-SIG1 (Q-BPSK) modulation according to BPSK but on normal axis with HT-SIG2 fields.In other words, compared with the modulation of L-SIG fields Compared with the modulation of HT-SIG1 and HT-SIG2 fields is rotated by 90 °.

Fig. 6 B are illustrated such as L-SIG, VHT- of the data cell 500 of Fig. 5 by defined in IEEE 802.11ac standards One group of diagram of the modulation of SIGA1 and VHT-SIGA2 fields.Unlike the HT-SIG1 fields in Fig. 6 A, VHT-SIGA1 field roots Modulate according to BPSK, it is identical with the modulation of L-SIG fields.On the other hand, compared with the modulation of L-SIG fields, VHT-SIGA2 words Section is rotated by 90 °.

Fig. 7 A are to be configured to be modulated to client stations 25-1 via orthogonal frequency domain multiplexing (OFDM) according to the AP 14 of embodiment The diagram of the OFDM data unit 700 of transmission.In embodiment, client stations 25-1 is additionally configured to send data cell 700 To AP 14.Data cell 700 meets the first communication protocol and occupies 20MHz bandwidth.In other embodiments, with data sheet The similar data cells for meeting the first communication protocol of unit 700 can take up other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.Data cell 700 is suitable to " mixed mode " situation, That is, when WLAN 10 includes meeting the client stations (for example, leaving client stations 25-4) of legacy communication protocols rather than the first communication protocol When.In certain embodiments, data cell 700 is also using in other cases.

In embodiment, data cell 700 includes leading 701, and it has L-STF 702, L-LTF 704, L-SIG 706th, including the two of HEW signal fields (HEW-SIGA1) 708-1 and the 2nd HEW signal fields (HEW-SIGA2) 708-2 An individual HEW signal fields (HEW-SIGA) 708, HEW short training fields (HEW-STF) 710, M HEW long training field (HEW-LTF) 712 (wherein, M is integer) and the 3rd HEW signal fields (HEW-SIGB) 714.L-STF 702、L-LTF 704th, each in L-SIG 706, HEW-SIGA 708, HEW-STF 710, M HEW-LTF 712 and HEW-SIGB 714 Including one or more OFDM symbols of integer number.For example, in embodiment, HEW-SIGA 708 includes two OFDM symbols Number, wherein, HEW-SIGA 708-1 fields include the first OFDM symbol, and HEW-SIGA2 includes the second OFDM symbol.Another In one embodiment, for example, leading 701 include the 3rd HEW signal fields (HEW-SIGA3, not shown) and HEW-SIGA 708 Including three OFDM symbols, wherein, HEW-SIGA 708-1 include the first OFDM symbol, and HEW-SIGA2 is accorded with including the 2nd OFDM Number, and HEW-SIGA3 includes the 3rd OFDM symbol.In at least some example, HEW-SIGA 708 is referred to as single HEW signals Field (HEW-SIGA) 708.In certain embodiments, data cell 700 also includes data division 716.In other embodiments, The omitted data part 716 of data cell 700.

In the embodiment of Fig. 7 A, data cell 700 includes L-STF 702, L-LTF 704, L-SIG 706, HEW- One in each in SIGA1 708.OFDM data unit similar with data cell 700 wherein is occupied except 20MHz It is sub to the 20MHz of the corresponding number of whole bandwidth of data cell in embodiment in the other embodiment of outer aggregate bandwidth Repeat each in L-STF 702, L-LTF 704, L-SIG 706, HEW-SIGA1 708 on frequency band.For example, in embodiment In, OFDM data unit occupies 80MHz bandwidth, and therefore includes L-STF 702, L-LTF 704, L-SIG in embodiment 706th, four in each in HEW-SIGA1 708.In certain embodiments, the tune of different 20MHz sub-band signals The different angle of system rotation.For example, in one embodiment, the first sub-band rotates 0 degree, and the second sub-band is rotated by 90 °, the Three sub-bands rotate 180 degree, and the 4th sub-band rotates 270 degree.In other embodiments, using different suitable rotations Turn.In at least some embodiments, the out of phase of 20MHz sub-band signals causes the OFDM symbol in data cell 700 The papr (PAPR) of reduction.In embodiment, if the data cell for meeting the first communication protocol is to occupy tired The OFDM data unit of product bandwidth (20MHz, 40MHz, 80MHz, 160MHz, 320MHz, 640MHz etc.), HEW-STF, HEW-LTF, HEW-SIGB and HEW data division occupies corresponding whole bandwidth of data cell.

Fig. 7 B are the L-SIG 706 of pictorial image 7A according to embodiment, the tune of HEW-SIGA1 708-1 and HEW-SIGA2 One group of diagram of system.In this embodiment, L-SIG 706, HEW-SIGA1 708-1 and HEW-SIGA2 708-2 fields have With the modulation identical modulation of the corresponding field as described in IEEE 802.11ac standards definition and Fig. 6 B.Therefore, with L-SIG fields modulate in the same manner HEW-SIGA1.On the other hand, compared with the modulation of L-SIG fields, the rotation of HEW-SIGA2 fields It turn 90 degrees.In some embodiments with the 3rd HEW-SIGA3 fields, identically with L-SIG fields and HEW-SIGA1 fields Modulation HEW-SIGA2, and compared with L-SIG fields, HEW-SIGA1 fields and HEW-SIGA2 fields, HEW-SIGA3 fields It is rotated by 90 °.

In embodiment, because the L-SIG 706 of data cell 700, HEW-SIGA 708-1 and HEW-SIGA 708-2 Field modulation with meet corresponding in the data cell (for example, the data cell 500 of Fig. 5) of IEEE 802.11ac standards The modulation of field is corresponding, so being configured to according to IEEE 802.11a standards and/or IEEE 802.11n standard operations Leave client stations to it will be assumed at least some embodiments, data cell 700 meets IEEE 802.11ac standards and by accordingly Ground processes data cell 700.For example, the client stations of IEEE 802.11a standards are met by the leading of Identification Data unit 700 Leave IEEE 802.11a criteria sections and by holding according to duration setting data unit indicated in L-SIG 706 Continuous time (or data cell duration).For example, according to embodiment, leaving client stations 25-4 will be based in L-SIG field 706 Indicated speed and length (for example, in units of byte number), calculate the duration for data cell.In embodiment In, the speed and length in L-SIG fields 706 is set so that be configured to the visitor according to legacy communication protocols operation Family station will be calculated packet corresponding with the actual duration of data cell 700 or at least approximate and held based on speed and length Continuous time (T).For example, in one embodiment, speed be set to indicate it is minimum by defined in IEEE 802.11a standards Speed (that is, 6Mbps), and length is set to calculated value so that when the packet calculated using minimum speed limit is continued Between at least approximate data unit 700 the actual duration.

In embodiment, when when leaving client stations receiving data unit 700 of IEEE 802.11a standards is met, will for example The duration for data cell 700 is calculated using the speed field and length field of L-SIG fields 706, and is being implemented The end of the packet duration until being calculated will be waited in example before clear channel assessment (CCA) (CCA) is performed.Therefore, at this In embodiment, prevent communication media from being accessed by client stations are left at least for the duration of data cell 700.In embodiment In, leaving client stations will continue decoding data unit 700, but by the error checking (example at the ending for making data cell 700 Such as, using Frame Check Sequence (FCS)) failure.

Similarly, in embodiment, receive when the client stations of leaving according to IEEE 802.11n standard operations are configured to During data cell 700, by speed and length indicated in the L-SIG 706 based on data cell 700, data cell is calculated 700 packet duration (T).Leaving client stations will detect the modulation of HEW signal fields (HEW-SIGA1) 708-1 (BPSK) and it will be assumed that data cell 700 is the Legacy Data unit for meeting IEEE 802.11a.In embodiment, visitor is left Family station will continue decoding data unit 700, but will make the error checking at the ending of data cell (for example, using frame check Sequence (FCS)) failure.In any case, according to IEEE 802.11n standards, in embodiment, leaving client stations will hold The end of the packet duration (T) until being calculated is waited before row clear channel assessment (CCA) (CCA).Therefore, in embodiment, To prevent communication media from being accessed by client stations are left for the duration of data cell 700.

In embodiment, when being configured to leaving according to IEEE 802.11ac standards rather than the first communication protocol operations During client stations receiving data unit 700, speed and length indicated in the L-SIG 706 based on data cell 700 are calculated The packet duration (T) of data cell 700.However, in embodiment, leaving client stations and will not be able to based on data cell 700 modulation and detection data unit 700 does not meet IEEE 802.11ac standards.In certain embodiments, data cell 700 One or more HEW signal fields (for example, HEW-SIGA1 and/or HEW-SIGA2) it is formatted with intentionally cause leave Client stations detect mistake in decoding data unit 700 and therefore stop decoding (or " discarding ") data cell 700.For example, In embodiment, the HEW-SIGA 708 of data cell 700 is formatted with when SIGA fields are according to IEEE 802.11ac standards When being decoded by legacy devices, intentionally cause mistake.And, according to IEEE 802.11ac standards, in embodiment, when in solution When detecting mistake in code VHT-SIGA fields, client stations will abandon data cell 700 and perform clear channel assessment (CCA) (CCA) institute that the indicated speed in the L-SIG 706 for example based on data cell 700 of wait and length are computed before The end of the packet duration (T) of calculating.Therefore, in embodiment, will prevent from leading to for the duration of data cell 700 Letter medium is accessed by client stations are left.

Fig. 8 is the diagram of the OFDM symbol 800 according to embodiment.In embodiment, the data cell 700 of Fig. 7 is including all Such as the OFDM symbol of OFDM symbol 800.OFDM symbol 800 includes protection interval (GI) part 802 and message part 804.In reality In applying example, protection interval includes the Cyclic Prefix of the ending for repeating OFDM symbol.In embodiment, protection interval part The orthogonality of the 802 OFDM tones (tone) for being employed to ensure that receiving device (for example, client stations 25-1) place and minimize or Elimination is attributed to the intersymbol interference of the multipath transmisstion in communication channel, and OFDM symbol 800 sets via the communication channel from transmission Standby (for example, AP 14) is sent to receiving device.In embodiment, based on the communication channel between the equipment of transmission and receiving device In expectation worst case channel time delay spread, select the length of protection interval part 802.For example, in embodiment, and it is directed to Generally compared compared with short protection interval by the indoor communications channel characterized compared with short channel time delay spread is selected, for usual Selected compared with long protection interval by the outdoor communication channel characterized compared with long channel time delay spread.In embodiment, based on The tone spacing that generation message part 804 is utilized is (for example, between the sub-carrier frequencies of the full width of data cell Away from), select the length of protection interval part 802.For example, with the shorter guarantor for wider tone spacing (for example, 64 tones) Shield spacing compares, and selects compared with long protection interval for narrower tone spacing (for example, 256 tones).

According to embodiment, depending on the transmission mode for being utilized, protection interval part 802 and short protection interval, normal guarantor Shield interval or long protection interval are corresponding.In embodiment, short protection interval or normal protection interval are used for indoor communications letter Between road, the communication channel with the diffusion of relatively short channel delay or the communication channel with appropriate high SNR ratios, and long protection Every being used for outdoor communication channel, the communication channel with relatively long time delay spread or there is no the communication of appropriate high SNR ratios Channel.In embodiment, when HEW data cells are sent in normal mode, normal protection interval or short protection interval by with In some or all OFDM symbols of HEW data cells (for example, HEW data cells 700), and when in scope mode of extension When sending HEW data cells, long protection interval is used at least some OFDM symbol of HEW data cells.

In embodiment, short protection interval (SGI) has the length of 0.4 μ s, and normal protection interval is 0.8 μ s, and long Protection interval (LGI) has the length of 1.2 μ s or 1.8 μ s.In embodiment, message part 804 has the length of 3.2 μ s. In other embodiment, message part 804 has the increase corresponding with tone spacing that message part 804 utilized has been generated Length.For example, message part 804 has 3.2 μ s' of the normal mode for the first tone spacing using 64 tones Second length of the first length and the 6.4 μ s with the second tone spacing for 128 tones, wherein, with the first tone Spacing compares with the first length, the integral multiple of the second tone spacing and the second length thereof increase by 2.In embodiment, information The residue length of part 804 is filled with the copy of received time-domain signal, and (for example, message part 804 is comprising being received Time-domain signal two copies).In other embodiments, using for SGI, NGI, LGI and/or message part 804 its The length that he is adapted to.In certain embodiments, SGI has the length of the 50% of the length of NGI, and NGI has as LGI's The length of the 50% of length.In other embodiments, SGI has the length of 75% or less of the length of NGI, and NGI has Have LGI length 75% or less length.In other embodiments, SGI has the length of 50% or less of the length of NGI Degree, and NGI have LGI length 50% or less length.

In other embodiments, the OFDM modulation with the tone spacing for reducing is using in the model planned using same tone Enclose in mode of extension that (for example, indicator is to the pre- of data tones, pilot tones and/or protection tone assignment which OFDM tone Determine index sequence).For example, for 20MHz bandwidth OFDM data units normal mode using causing 64 OFDM tone (examples Such as, index -32 to+31) 64 point discrete Fouriers in leaf transformation (DFT), scope mode of extension using cause in same band 128 The 128 point DFT for 20MHz OFDM data units of individual OFDM tones (for example, index -64 to+63).In this case, Tone spacing compared with the normal mode OFDM symbol when being planned using same tone, in scope mode of extension OFDM symbol Reduced (1/2) with the factor 2.As another example, for 20MHz bandwidth OFDM data units normal mode using causing 64 Leaf transformation (DFT) in 64 point discrete Fouriers of OFDM tones, scope mode of extension is using causing being directed to for 256 OFDM tones 256 point DFT of 20MHz OFDM data units.In this case, compared with normal mode OFDM symbol, scope expanded mode Tone spacing in formula OFDM symbol is reduced (1/4) with the factor 4.In such embodiments, held using the long GI of such as 1.6 μ s The continuous time.However, in embodiment, duration of the message part of scope mode of extension OFDM symbol increase (for example, from 3.2 μ s of μ s to 6.4), and GI section durations are identical with the percentage holding of total OFDM symbol duration.Therefore, exist In this case, at least some embodiments, it is to avoid be attributed to the loss in efficiency of longer GI symbols.In various embodiments In, as used herein term " long protection interval " covers the duration of the increase of protection interval and is effectively increased protection The OFDM tone spacing of the reduction of the duration at interval.

Fig. 9 A are to be used for the leading of data cell according to diagram wherein normal mode or the scope mode of extension of embodiment Exemplary data cells 900 diagram.Data cell 900 it is substantially identical with the data cell 700 of Fig. 7 A and including with Fig. 7 A The equally numbering of data cell 700 element.(for example, the HEW-SIGA1 708-1 of HEW-SIGA fields 708 of data cell 900 Or HEW-SIGA2 708-2) include that coding indicates (CI) 902. according to embodiment, CI indicate 902 be set to indicate it is following it One (i) there is the normal mode or (ii) of conventional encoding scheme to have the scope mode of extension of scope extended coding scheme.In reality In applying example, CI indicates that 902 include a bit, wherein, the first value of bit indicates normal mode, and the second value of bit refers to Mode of extension is enclosed in demonstration.In certain embodiments, CI is indicated in combination with modulation and encoding scheme (MCS) designator.Implementing In example, for example, normal mode is with to be defined as effective MCS value by legacy receiver equipment corresponding (for example, it then follows IEEE 802.11ac agreements), and scope mode of extension is relative with the MSC values for being defined as invalid (or not supporting) by legacy receiver equipment Answer (for example, not following IEEE 802.11ac agreements).In other embodiments, CI indicates that 902 have multiple bits, its instruction Multiple normal mode MCS values and multiple scope mode of extension MCS values.As illustrated in Fig. 9 A, in the illustrated embodiment, Conventional encoding scheme is used for leading all OFDM symbols of data cell 700, and normal as indicated by indicating 902 by CI Rule one of encoding scheme or scope extended coding scheme are used for the OFDM symbol of data division 716.

It is and normal for example wherein scope extended coding scheme is used in the embodiment of the OFDM symbol of data division 716 Rule data cell compares, PHY data unit be successfully decoded present scope and/or SNR generally yield improvement (that is, compared with It is successfully decoded at long scope and/or relatively low SNR).In certain embodiments, it is leading for what is generated using conventional encoding scheme Improved scope and/or SNR performances is not necessarily realized in 701 decoding.In such embodiments, be used for transmission data The through-put power of part 716 compares, and with the leading at least one of transmission that through-put power is lifted leading 701 are increased The decoding ranges for dividing.In certain embodiments, leading 701 part for being sent is lifted using through-put power to be included leaving field (such as L-STF 702, L-LTF 704 and L-SIG 708) and/or non-legacy field (such as HEW-STF and HEW-LTF). In various embodiments, it is 3dB, 6dB or other suitable values that through-put power is lifted.In certain embodiments, through-put power is carried Rise and be determined so that compared with " not boosted " data division 716 at same position, " boosted " leading 701 It is decodable with similar performance.In certain embodiments, the L-STF 702 of the length of increase, L-LTF 704 and/or L-SIG 706 lifted with through-put power is applied in combination.In other embodiments, through-put power is replaced to be lifted, using increased length L-STF 702, L-LTF 704 and/or L-SIG 706.

Fig. 9 B are leading one that data cell is used for according to the diagram wherein scope extended coding scheme of embodiment The diagram of the exemplary data cells 950 divided.Except data cell 950 includes the encoding scheme wherein by indicated by CI indicates 902 It is suitable to outside leading the 751 of the OFDM symbol of the OFDM symbol of leading 751 part and data division 716, data cell 950 It is substantially identical with the data cell 900 of Fig. 9 A.Especially, in the illustrated embodiment, normal encoding scheme is used for leading 701 Part I 751-1, and the normal volume in addition to the OFDM symbol of data division 716, as indicated by indicating 902 by CI Code one of scheme or scope extended coding scheme are used for the OFDM symbol of leading 751 Part II 751-2.Therefore, in institute In the embodiment of diagram, the encoding scheme by indicated by CI information 902 skips the OFDM symbol corresponding with HEW-STF 710 simultaneously And start to be applied with the OFDM symbol corresponding with HEW-LTF 712-1.In at least some embodiments, HEW- is skipped STF 710 allows the equipment enough time of receiving data unit 950 to exist to decode CI instructions 902 and suitably arrange receiver Receive the encoding scheme decoding OFDM symbol begun to use before such OFDM symbol by indicated by CI indicates 902.

Figure 10 A are adjusted and the ratio for scope extended coding scheme according to the diagram wherein OFDM tones spacing of embodiment The diagram of the exemplary data cells 1000 that special and/or symbol repeated combination is used.Data cell 1000 substantially with the data of Fig. 7 A Unit 900 is identical, except in data cell 1000, when CI indicates 902 instructions just in utilization scope extended coding scheme, making With with the tone spacing of reduction compared with the tone spacing of normal mode OFDM symbol of data cell 1000 is used for OFDM modulates to generate the OFDM symbol of data division 716.

Figure 10 B are to be adjusted according to the diagram wherein OFDM tones spacing of another embodiment and be directed to scope extended coding scheme Bit and/or the diagram of exemplary data cells 1050 that uses of symbol repeated combination.Data cell 1050 usually with Fig. 9 B Data cell 950 it is identical, except in data cell 1050, when CI indicate 902 indicate utilization scope extended coding scheme when, Using the tone spacing with the reduction compared with the tone spacing of the normal mode OFDM symbol of data cell 1050 is used for OFDM modulation generate Part II 751-2 OFDM symbol and data division 716 OFDM symbol.Shown in Figure 10 A Normal pitch spacing and protection interval and the sound of reduction 2 in embodiment, in the total bandwidth and Part I 751-1 of 20MHz Spacing, long protection interval and FFT sizes 64 is adjusted to be repeated twice across total bandwidth and be used together.In certain embodiments, work(is transmitted Rate is lifted and is applied to Part I 751-1.In other embodiments, other multiples such as 4x, 8x or other suitable values by with One or more in following：The tone spacing of reduction, increased protection interval, increased symbol duration cross over total The repetition of the increase of bandwidth.

In certain embodiments, be used for normal mode data cell it is leading compared with, different leading form quilts For scope mode of extension data cell.In such embodiments, the equipment of receiving data unit can be based on data cell Leading form, it is normal mode data cell or scope mode of extension data cell to automatically detect data cell.Figure 11A is the diagram of the diagram normal mode data cell 1100 according to embodiment.Normal mode data cell 1100 includes conventional Pattern leading 1101.Normal mode leading 1101 is substantially identical with leading the 701 of the data cell 700 of Fig. 7 A.In embodiment, Leading 1101 include HEW-SIGA fields 1108, and it includes HEW-SIGA1 fields 1108-1 and the two the first HEW-SIGA2 Field 1108-1.In embodiment, leading 1101 (for example, the HEW-SIGA1 1108-1 or HEW- of HEW-SIGA fields 1108 SIGA2 1108-2) include that CI indicates 1102.In embodiment, it is scope extended coding side that CI instructions 1102 are set to instruction Case or conventional encoding scheme are used for the OFDM symbol of the data division 716 of data cell 1100.In embodiment, CI is indicated 1102 include a bit, wherein, the first value of bit indicates conventional encoding scheme, and the second value indicating range of bit expands Exhibition encoding scheme.As will be explained in greater, in embodiment, the equipment of receiving data unit 1100 can be based on leading 1101 form and detect that leading 1101 is that normal mode is leading rather than mode of extension is leading.In embodiment, once detect Leading 1101 is that normal mode is leading, then receiving device indicates 1102 based on CI, it is determined that being scope extended coding scheme or often Rule encoding scheme is used for the OFDM symbol of data division 716 and correspondingly decoding data part 716.In some embodiments In, when CI indicates 1102 instructions by utilization scope extended coding scheme, with the normal mode for being used for data cell 1050 The tone spacing of OFDM symbol compares, and leading 1101 are generated (for example, such as using the modulation of the OFDM with less tone spacing HEW-LTF and HEW-SIGB) a part OFDM symbol and the OFDM symbol of data division 716.

Figure 11 B are the diagrams of the diagram scope mode of extension data cell 1150 according to embodiment.Scope mode of extension number Include scope mode of extension leading 1151 according to unit 1150.Before leading 1151 and data cell 1100 of data cell 1150 Lead 1101 differently formatted outer, data cell 1150 is substantially similar with the data cell 1100 of Figure 11 A.In embodiment, It is formatted to leading 1151 so that can determine that leading 1151 is scope according to the receiving device of HEW communication protocol operations Mode of extension is leading rather than normal mode is leading.In embodiment, scope mode of extension leading 1151 include L-STF 702, L-LTF 704 and L-SIG 706 and one or more HEW signal fields (HEW-SIGA) 1152.It is leading in embodiment 1150 also include following one or more secondary L-SIG 1154 of L-SIG fields 706.In certain embodiments, (one more It is individual) secondary L-SIG is followed by the 2nd L-LTF fields (L-LTF2) 1156.In other embodiments, leading 1151 (one is omitted Or multiple) L-SIG 1154 and/or L-LTF2 1156.In certain embodiments, leading 1151 also include HEW-STF 1158, One or more HEW signal fields (HEW-SIGB) 1162 of HEW-LTF fields 1160 and the 2nd.In other embodiments, it is leading 1151 omit HEW-STF 1158, (one or more) HEW-LTF 1160 and/or HEW-SIGB 1162.In embodiment, number Also include data division 716 (not shown in Figure 11 B) according to unit 1150.In certain embodiments, use and data field 716 Identical scope extended coding modulating scheme HEW signal fields (HEW-SIGA) 1152.

In embodiment, one or more symbols of HEW-SIGA 1152 are adjusted using such as QBPSK rather than BPSK System, with the automatic detection between the normal mode and scope mode of extension that allow the receiving device according to HEW communication protocol operations. In embodiment, for example, the two BPSK symbols and a Q-BPSK after the leading field including L-SIG 706 of normal mode Three BPSK symbols and a Q-BPSK in the case of symbol, after the leading field including L-SIG 706 of scope mode of extension Symbol.In embodiment, for example, the 4x of the MCS0 of 48 data tones in using with each 64-FFT (20MHz) is pressed When position is repeated.In certain embodiments, for example, in the case where automatic detection is by normal mode and the differentiation of scope mode of extension, Some bits are omitted from HEW-SIGA 1152, bit or other suitable ratios that such as indication signal bandwidth, MCS value are used It is special.

Wherein leading 1151 are included in one embodiment of one or more secondary L-SIG 1154, (one or more) The content of each in L-SIG 1154 is identical with the content of the L-SIG 706 of data cell 1150.In embodiment, receive The receiving device of data cell 1150 repeats to determine leading 1151 by (one or more) of detection L-SIG fields 706,1154 It is leading with scope mode of extension corresponding.And, in embodiment, the speed son field and Length subfield two of L-SIG 706 Person and (one or more) speed son field and (one or more) of corresponding (one or more) secondary L-SIG 1154 Length subfield is set to (for example, making a reservation for) value of fixation.In this case, in embodiment, once detect L-SIG (one or more) of field 706,1154 repeat, then the fixed value in the L-SIG fields that receiving device will repeat is used as additional Training information is improving channel estimation.However, in certain embodiments, at least Length subfield of L-SIG 706 and corresponding The Length subfield of at least (one or more) secondary L-SIG 1154 be not set to fixed value.For example, in embodiment, Length field is set on the contrary the value based on determined by the physical length of data cell 1150.In such embodiment In, receiving device decodes first L-SIG 706, and and then using the Length subfield detection L-SIG fields in L-SIG 706 706th, 1154 (one or more) repeat.In another embodiment, receiving device detects first L-SIG fields 706,1154 (one or more) repeat, and and then by detection multiple L-SIG fields 706,1154 combination with improve L-SIG fields 706, 1154 decoding reliability and/or using in multiple L-SIG fields 706,1154 redundancy improve channel estimation.

Wherein leading 1151 are included in the embodiment of L-LTF2 1156, use range extended coding schemes generation L- (one or more) OFDM symbol of LTF2 1156.Wherein leading 1151 are included in another embodiment of L-LTF2 11156, (one or more) OFDM symbol of L-LTF2 1156 is generated using conventional encoding scheme.If using in L-LTF 704 Double protection interval (DGI) is for the communication channel that wherein data cell 1150 advances to receiving device from transmission equipment It is sufficiently long, then using the OFDM symbol of conventional encoding scheme generation L-LTF2 1156, or alternatively, in embodiment, Leading 1151 omit L-LTF2 1156.

In another embodiment, leading 1151 (one or more) secondary L-SIG 1154 is omitted, but including L-LTF2 1156.In this embodiment, receiving device detects that leading 1151 is scope expanded mode by detecting the presence of L-LTF2 1156 Formula is leading.Figure 12 A-12B are two possibility of the LTF that L-LTF2 1156 is suitable for use as according to the diagram of two example embodiments The diagram of form.Be tuning firstly to Figure 12 A, in the first example embodiment, L-LTF2 1200 with the identical sides of L-LTF 704 Formula is formatted, i.e. such as defined by legacy communication protocols (for example, IEEE 802.11a/n/ac standards).Especially, exist In shown embodiment, L-LTF2 1200 includes the double protection of two repetitions 1204,1206 for being followed by long training sequence Interval (DGI) 1202.Turning now to Figure 12 B, in another example embodiment, L-LTF2 by with the differently forms of L-LTF 704 Change.Especially, in the illustrated embodiment, L-LTF2 1208 includes the first normal protection interval 1210, long training sequence First the second repetition 1216 for repeating the 1212, second normal protection interval 1214 and long training sequence.

Referring back to Figure 11 B, in embodiment, use range extended coding schemes generation (one or more) HEW-SIGA 1152.In embodiment, the number of HEW-SIGA 1152 and (one or more) HEW-SIGA of normal mode leading 1101 1108 number is identical.Similarly, in embodiment, the content of HEW-SIGA 1152 with (one of normal mode leading 1101 Or multiple) content of HEW-SIGA 1108 is identical.In other embodiments, the number and/or content of HEW-SIGA 1152 with The number of (one or more) HEW-SIGA 1108 of normal mode leading 1101 and/or content are different.In embodiment, connect The equipment for receiving data cell 1150 is leading with scope mode of extension corresponding based on detecting leading 1151, and use range extension is compiled (one or more) HEW-SIGA 1152 is decoded and suitably interpreted as defined in scope mode of extension by code scheme (one or more) HEW-SIGA 1152.

Leading 1151 omit in the embodiment of (one or more) L-SIG 1154 and/or L-LTF2 1156 wherein, connect Receiving unit is detected by the auto-correlation based on use range extended coding scheme and the HEW-SIGA fields of conventional encoding scheme HEW-SIGA fields in leading are that use range extended coding scheme or conventional encoding scheme are generated, determine it is leading be with Scope mode of extension leading 1151 or normal mode are leading 1101 corresponding.Figure 13 A-13B are respectively according to the normal of embodiment The HEW-SIGA 1108 of the scale formula leading 1101 and HEW-SIGA 1152 of scope mode of extension leading 1151.Illustrated In embodiment, the HEW-SIGA 1108 of normal mode leading 1101 includes a NGI 1302, a HEW-SIGA fields 1304th, the 2nd NGI 1306 and the 2nd HEW-SIGA fields 1308.On the other hand, the HEW- of scope mode of extension leading 1151 SIGA 1152 includes a LGI 1310, a HEW-SIGA fields 1312, the 2nd LGI 1314 and the 2nd HEW-SIGA fields 1312.In embodiment, receiving device performs HEW- using normal protection interval structure (illustrated structure in such as Figure 13 A) First auto-correlation of SIGA fields, second is performed from phase using long protection interval structure (illustrated structure in such as Figure 13 B) Close, and perform the comparison of autocorrelation result.In embodiment, if using long protection interval HEW-SIGA fields from phase Close and produce more larger result compared with the autocorrelative result of the HEW-SIGA fields using normal protection interval, then receive Equipment determines that leading leading with scope mode of extension 1151 is corresponding.On the other hand, in embodiment, if using normal protection The auto-correlation of the HEW-SIGA fields at interval produces the autocorrelative result phase with the HEW-SIGA fields using long protection interval The larger result of comparison, then receiving device determines that leading leading with normal mode 1101 is corresponding.

Figure 11 B are referred again to, in embodiment, is formatted to leading 1151 so that leave client stations and can determine The duration of data cell 1150 and/or data cell do not meet legacy communication protocols.Additionally, in embodiment, to leading 1151 are formatted so that can determine that data cell meets HEW communication protocols according to the client stations of HEW agreements operation.Example Such as, (such as (one or more) L-SIG 1154 of L-SIG 706 for immediately follows following leading 1151 are modulated using BPSK modulation And/or L-LTF2 1156 and/or (one or more) HEW-SIGA 1152) at least two OFDM symbols.In such case Under, in embodiment, leaving client stations will regard Legacy Data unit as data cell 1150, will be determined based on L-SIG 706 The duration of data cell and duration determined by being directed to suppress to access medium.And, it is leading in embodiment One or more of 1151 other OFDM symbols (one or more in such as (one or more) HEW-SIG 1152) are to make Modulated with Q-BPSK modulation, this permission meets HEW according to the client stations detection data unit 1150 of HEW communication protocol operations Communication protocol.

In certain embodiments, the beam forming and/or multiuser MIMO in HEW communication protocols allowed band mode of extension (MU-MIMO) transmit.In other embodiments, in HEW communication protocols allowed band mode of extension it is only single stream and/or it is only single Individual user's transmission.With continued reference to Figure 11 B, wherein leading 1151 include HEW-STF 1158 and (one or more) HEW-LTF In 1160 embodiment, AP 14 is started with HEW-STF 1158, using beam forming and/or multi-user transmission.In other words, In embodiment, the field of leading 1151 before HEW-STF 1158 is omnidirectional, and is intended in multi-user mode Received by the intended recipient of data cell 1150, and HEW-STF fields 1158 and follow the leading of HEW-STF fields 1158 Field and leading 1151 data division is followed by beam forming and/or including being intended to by the different expection of data cell 1150 The different piece that recipient receives.In embodiment, HEW-SIGB fields 1162 are included for the data sheet in MU-MIMO patterns The specific information of user of the intended recipient of unit 1150.Depending on embodiment, compiled using conventional encoding scheme or scope extension Code schemes generation HEW-SIGB fields 1162.Similarly, depending on embodiment, using conventional encoding scheme or scope extended coding Schemes generation HEW-STF 1158.In embodiment, the training sequence used on HEW-STF 1158 is in Legacy communications In agreement (such as in IEEE 802.11ac agreements) defined in sequence.

On the other hand, leading 1151 reality for omitting HEW-STF 1158 and (one or more) HEW-LTF 1160 wherein In applying example, beam forming and MUMIMO are not allowed in extended protection interval mode.In this embodiment, it is spaced in extended protection Only single user single-stream transmission is allowed in pattern.In embodiment, receiving device obtains single current channel and estimates based on L-LTF fields 704 Meter, and according to the channel estimation obtained based on L-LTF fields 704, the data division of data cell 1150 is demodulated.

In certain embodiments, receiver apparatus are restarted for receiving data part using HEW-STF fields 1158 716 automatic growth control (AGC) process.In embodiment, HEW-STF has and the VHT-STF identical duration (that is, 4 Microsecond).In other embodiments, HEW-STF has the duration longer than VHT-STF.In embodiment, HEW-STF tools Have and VHT-STF identical time domain periodics so that in a frequency domain, there is a non-zero tone every 4 tones and use With IEEE 802.11ac same tone spacing.In the other embodiment with 1/N tone spacing, HEW-STF is per 4*N sound Adjust and there is a non-zero tone.It is more than 20MHz (for example, 40MHz, 80MHz etc.) for the total bandwidth of data cell wherein Embodiment, HEW-STF using bandwidth VHT-STF wider with IEEE 802.11ac identicals (that is, for 40MHz, The duplication of the 20MHz VHT-STF of 80MHz, 160MHz etc.).

Figure 14 A are the block diagrams of the diagram scope mode of extension data cell 1400 according to embodiment.Data cell 1400 is wrapped Include scope mode of extension leading 1401.Except leading 1151 L-SIG 706 and secondary L-SIG 1154 is combined as in leading 1401 Single L-SIG fields 1406 outside, scope mode of extension leading 1401 substantially with leading 1151 class of the scope mode of extension of Figure 11 B Seemingly.Figure 14 B are the diagrams of the diagram L-SIG fields 1406 according to one embodiment.In the embodiment of Figure 14 B, L-SIG fields 1406 include double protection interval 1410, (it includes the interior of leading 1151 L-SIG fields 706 to a L-SIG fields 1412 Hold) and the 2nd L-SIG fields 1414 (it includes the content of leading 1151 secondary L-SIG2 fields 1154).In various embodiments In, L-SIG fields 1406 include being set to fixed value or being set to the Length subfield of variable value, as above for Figure 11 B What L-SIG fields 706,1154 were discussed.In various embodiments, in L-SIG fields 1406 redundancy (repetition) bit quilt Discussed for improved channel estimation, such as the L-SIG fields 706,1154 above for Figure 11 B.

In embodiment, the client stations of leaving of receiving data unit 1400 assume that L-SIG fields 1406 include normal protection Interval.As illustrated in Figure 14 C, in this embodiment, compared with actual L-SIG fields 1412, leave at client stations It is assumed that the FFT windows for L-SGI information be shifted by.It is desired in order to ensure such as leaving client stations in embodiment, Constellation point in FFT windows is corresponding with BPSK modulation, and therefore suitably decodes L-SIG words to allow to leave client stations Modulation phase shift relative to conventional BPSK modulation of 1412, L-SIG of section fields 1412.For example, in 20MHz OFDM symbols, such as The normal protection interval of fruit is 0.8 μ s, and double protection interval is 1.6 μ s, then the OFDM tone k's of L-SIG fields 1412 Modulation offsets with regard to the corresponding OFDM tones k of original L-SIG, such as can see from following：

Therefore, in embodiment, using reversion Q-BPSK rather than conventional BPSK modulation L-SIG fields 1412.Therefore, example Such as, in embodiment, the bit of value 1 is modulated onto on j, and the bit of value 0 is modulated onto on j, and this produces { j ,-j } modulation Rather than conventional { 1, -1 } BPSK modulation.In embodiment, because the reversion Q-BPSK of L-SIG fields 1412 is modulated, thus lose Stay client stations suitably to decode L--SIG fields 1412, and in embodiment, based on the fields of L-SIG 1412, determine number According to the duration of unit 1400.On the other hand, in embodiment, can be by detection according to the client stations of HEW agreements operation The repetition of L-SIG fields 1412 or the reversion Q-BPSK tune by detecting the L-SIG fields left in the FFT windows of client stations System, automatic detection leading 1401 is that scope mode of extension is leading.Alternatively, in other embodiments, according to the operation of HEW agreements Client stations use other detection method (modulation such as based on (one or more) HEW-SIGA fields 1152 as discussed above Or form) detect that leading 1401 is that scope mode of extension is leading.

With reference to Figure 11 A-11B and 14A, in certain embodiments, it is leading (for example, that long protection interval is used for normal mode It is leading 1101) and leading (for example, the leading 1151 or leading 1401) initial OFDM symbols of the two of scope mode of extension.For example, With reference to Figure 11 A-11B, in embodiment, L-STF fields 702, L-LTF fields 704 and L-SIG fields 706,1154 and HEW- SIGA fields 1152 are individually what is generated using long protection interval.Similarly, with reference to Figure 14 A, in embodiment, L-STF words Section 702, L-LTF fields 704, L-SIG fields 1406 and (one or more) HEW-SIGA 1152 are come using long protection interval Generate.In embodiment, receiving device can be based on HEW-SIGA fields 1152 modulation (for example, Q-BPSK) or based on The instruction being included in various embodiments in HEW-SIGA fields 1152, determines that leading is leading with normal mode or and scope Mode of extension is leading corresponding.And, similar with leading the 1151 of Figure 11 B, leading the 1401 of Figure 14 A includes or omits the 2nd L- LTF2 fields 1156, this depends on embodiment and/or scene.

Figure 15 is the block diagram of the form of the diagram HEW-SIGA fields 1500 according to embodiment.In certain embodiments, number HEW-SIGA fields 1500 are formatted as according to (one or more) HEW-SIGA fields of unit 1150 or data cell 1400. In certain embodiments, the formatted HEW-SIGA fields 1500 of (one or more) HEW-SIGA fields 1108.HEW-SIGA Field 1500 includes double protection interval 1502, the second weight of the first 1504 and HEW-SIGA fields of repetition of HEW-SIGA fields Multiple 1506.In the exemplary embodiment, DGI is 1.8 μ s, and it is 3.2 μ s that each of HEW-SIGA repeats.In embodiment, The bit of the repetition in HEW-SIGA fields 1500 is used for the reliability of the decoding for increasing HEW-SIGA fields 1500.Implementing In example, the form of HEW-SIGA fields 1500 is used for the leading HEW-SIGA words based on the form for using HEW-SIGA fields 1500 The auto-correlation of section and the conventional H EW-SIGA field format with use used in normal mode are (illustrated in such as Figure 13 A Form) leading HEW-SIGA fields auto-correlation between comparison, automatic detection scope mode of extension is leading.In some realities In applying example, HEW-SIGA fields 1500 are modulated using less redundancy compared with data division 716, because HEW-SIGA fields 1500 appended time domain repeats to provide being sufficiently improved for decoding performance.

Figure 16 is to be used to generate the example of normal mode data cell using conventional encoding scheme according to the diagram of embodiment The block diagram of PHY processing units.With reference to Fig. 1, in one embodiment, it is single that AP 14 and client stations 25-1 each includes that PHY is processed Unit, such as PHY processing units 1600.In various embodiments and/or scene, the formation range spreading number of PHY processing units 1600 According to unit, such as one of data cell of Fig. 9 A, 9B, 10A or 10B.PHY processing units 1600 include scrambler 1602, Its usual scramble information bit stream is reducing the appearance of one or zero long sequence.The information bit of 1606 pairs of scramblings of FEC encoder Encoded to generate encoded data bit.In one embodiment, FEC encoder 1606 includes Binary Convolutional Code (BCC) encoder.In another embodiment, FEC encoder 1606 includes being followed by the binary convolutional encoder of punch block. In another embodiment, FEC encoder 1606 includes low-density checksum (LDPC) encoder.Interleaver 1610 receives warp knit code Data bit and enter the Bit Interleave order of bit (that is, change) with the long sequence for preventing adjacent noise bit receive Decoder at device.It is relative that the interleaved sequence of bit is mapped to different subcarriers from OFDM symbol by constellation mapper 1614 The constellation point answered.More particularly, for each spatial flow, constellation mapper 1614 is by each bit of length log2 (M) Sequence translates to one of M constellation point.

The output resume of constellation mapper 1614 is operated by inverse discrete Fourier transform (IDFT) unit 1618, and it is by constellation Point block is converted to time-domain signal.Wherein PHY processing units 1600 operate to generate for via the number of multiple spatial stream transmissions According in the embodiment or situation of unit, cyclic shift insertion is removed and prevents unintentionally ripple by cyclic shift diversity (CSD) unit 1622 In the whole of one of the spatial flow of beam shaping.The output of CSD unit 1622 is provided to protection interval (GI) insertion and windows units 1626, it adds the annular expansion of OFDM symbol before OFDM symbol and smooths the edge of each symbol pair to increase frequency Spectrum decay.GI inserts and opens a window the output of unit 1626 and provides to simulation and radio frequency (RF) unit 1630, and it is converted a signal into Analog signal and up-convert the signals to for transmission RF frequency.

In various embodiments, minimum data rate modulation and encoding scheme of the scope mode of extension with normal mode (MCS) it is corresponding and by the redundancy of bit or be repeatedly introduced in the repetition of at least some field of data cell or symbol to enter One step reduces data rate.For example, in various embodiments and/or scene, scope mode of extension is according to described below one Individual or multiple scope extended coding schemes introduce redundancy into the data division of scope mode of extension data cell and/or non-legacy letter In the repetition of number field or symbol.As an example, according to embodiment, normal mode data sheet is generated according to conventional encoding scheme Unit.In various embodiments, conventional encoding scheme is the MCS, such as MCS0 (two selected from one group of modulation and encoding scheme (MCS) System phase shift keying (BPSK) modulates the code rate with 1/2) to MCS9 (quadrature amplitude modulation (QAM) and 5/6 coding speed Rate), and higher order MCS is corresponding with higher data rate.In one suchembodiment, use range extended coding Scheme (such as such as the modulation by defined in MCS0 and coding) and the repetition of increase bit, the block using further reduction data rate Coding or symbol repeat and formation range mode of extension data cell.

Figure 17 A are for use range extended coding schemes generation scope mode of extension data cell according to embodiment The block diagram of example PHY processing unit 1700.In certain embodiments, the formation range mode of extension data of PHY processing units 1700 The signal and/or data field of unit.With reference to Fig. 1, in one embodiment, AP 14 and client stations 25-1 each including PHY at Reason unit, such as PHY processing units 1700.

In addition to PHY processing units 1700 include the block encoder 1704 for being coupled to scrambler 1702, PHY processing units 1700 It is similar with the PHY processing units 1600 of Figure 16.In embodiment, 1704 plots of block encoder read incoming (scrambled ) information bit, some copies of each block (or each bit in block) are generated, according to scope extended coding scheme by gained Bit be interleaved and export interleaved bit for by (for example, the binary system convolutional encoding of FEC encoder 1706 Device) further encode.In general, according to embodiment, number of each block comprising information bit, it is via block encoder 1704 and the data tones of single OFDM symbol are filled after being encoded by FEC encoder 1706.As an example, in one embodiment In, block encoder 1704 generates two copies (2x repetitions) of each block of 12 information bits to generate OFDM to be comprised in 24 bits in symbol.Then 24 bits are encoded to generate modulation OFDM with 1/2 code rate by FEC encoder 1706 48 bits of 48 data tones (for example, being modulated using BPSK) of symbol.As another example, in another embodiment, Block encoder 1704 generates four copies (4x repetition) of each block of 6 information bits to generate 24 bits, its then with 1/2 code rate is encoded to generate 48 bits of 48 data tones of modulation OFDM symbol by FEC encoder 1706. Used as another example, in another embodiment, block encoder 1704 generates two copy (2x of each block of 13 information bits Repeat) to generate 26 bits, then it be encoded to modulate OFDM symbol with 1/2 code rate by FEC encoder 1706 52 data tones 52 bits of generation.In other embodiments, block encoder 1704 and FEC encoder 1706 are configured To generate the bit of 104,208 or any suitable numbers of the modulation of the data tones for OFDM symbol.

In certain embodiments, when generate such as by IEEE 802.11n standards be directed to 20MHz channels (that is, with 52 Individual data tones are per OFDM symbol) specified by MCS0 defined in data (or signal) field when, block encoder 1704 is applied 4x iteration schemes.In this case, according to embodiment, block encoder 1704 generates four of each block of 6 information bits Copy with generate 24 bits and and then two filling bits (that is, with predetermined value two bits) of addition with by specified number Purpose bit (that is, for 26 bits of 52 data tones) is supplied to BCC decoder, and it uses 1/2 code rate to compile Code 26 bits with generate for modulate 52 data tones 52 warp knit codes bit.

In one embodiment, block encoder 1704 utilizes " block level " iteration scheme, wherein, each n of continuous m repetition The block of individual bit.As an example, according to embodiment, if m be equal to 4 (4x repetitions), the formation sequence of block encoder 1704 [C, C, C, C], wherein, C is the block of n-bit.In another embodiment, block encoder 1704 utilizes " bit-level " iteration scheme, wherein, Repeat each input bit continuous m time.In this case, in embodiment, if m is equal to 4 (4x repetitions), block encoder 1704 formation sequences [b1 b1 b1 b1 b2 b2 b2 b2 b3 b3 b3 b3...], wherein, b1 is first in bit block Bit, b2 is second bit etc..In another embodiment, block encoder 1704 generate m numbers incoming bit copy simultaneously And the bit stream of gained is interweaved according to any suitable code.Alternatively, in another embodiment, block encoder 1704 is used and appointed What suitable code encodes incoming bit or incoming bit block, for example, the Hamming with 1/2,1/4 etc. code rate (Hamming) block code or any other block code with 1/2,1/4 etc. code rate (for example, (and 1,2) or (Isosorbide-5-Nitrae) block code, (12,24) block code or (6,24) block code, (13,26) block code etc.).

According to embodiment, with the coding by performed by block encoder 1704 and the coding by performed by FEC encoder 1706 The corresponding efficient coding speed of combination be two code rates product.For example, wherein block encoder 1704 is heavy using 4x Multiple (or 1/4 code rate) and FEC encoder 1706 are utilized in the embodiment of 1/2 code rate, the efficient coding of gained Speed is equal to 1/8.According to embodiment, as compared with the code rate that similar normal mode data cell is used is generated The result of the code rate of reduction, the data rate in scope mode of extension effectively with applied by block encoder 1704 The coefficient that the number of code rate is corresponding reduces (for example, 2 times, 4 times etc.).

According to some embodiments, block encoder 1704 utilizes and is used to generate the data division of control model data cell Block encoding scheme identical block encoding scheme for generate control model data cell signal field.For example, in embodiment In, the OFDM symbol of signal field and the OFDM symbol of data division each include 48 data tones, and in the embodiment In, for example, 2x iteration schemes are applied to block encoder 1704 block of 12 bits for signal field and data division.Another In one embodiment, using different block encoding schemes the data division and signal field of control model data cell are generated.For example, In embodiment, long range communication protocol is defined compared with the number of the data tones in data division per OFDM symbol, no With every OFDM symbol data tone of number.Therefore, in this embodiment, block encoder 1704 utilizes different block sizes, and And in certain embodiments, when operating to signal field, using be used for generate data division block size and coding staff The different encoding scheme of case.For example, according to one embodiment, if long range communication protocol specified signal field is every 48 data tones of every OFDM tones of 52 data tones of OFDM symbol and data division, then block encoder 1704 2x is repeated Scheme is applied to the block of 13 bits of signal field and 2x iteration schemes is applied to the block of 12 bits of data division.

According to embodiment, FEC encoder 1706 is encoded to the information bit that Jing blocks are encoded.In embodiment, inciting somebody to action BCC codings are consecutively carried out in the whole field (for example, whole data field, whole signal field etc.) for generating.Therefore, exist In the embodiment, the information bit corresponding with the field by generation be divided into specified size (for example, 6 bits, 12 bits, The bit of 13 bits or any other suitable number) block, each block is processed by block encoder 1704, and the data of gained Stream is provided to continuously encode the FEC encoder 1706 of incoming bit.

Similar with the interleaver 1610 of Figure 16, in various embodiments, interleaver 1710 changes the order of bit to carry For diversity gain and the successive bits in data flow are reduced in transmission channel by impaired chance.However, in some realities In applying example, block encoder 1704 provides enough diversity gains, and omits interleaver 1710.In certain embodiments, interweave Bit is supplied to constellation mapper 1614 for transmitting, as described above by device 1710 or FEC encoder 1706.

For example, in certain embodiments, the information bit in the data division of scope mode of extension data cell is filled (i.e., it is known that if the kilo byte of value is added to information bit) so that data cell occupies the OFDM symbol of integer number.With reference to figure 1, in certain embodiments, filling is realized in MAC processing units 18,28 and/or PHY processing units 20,29.At some so Embodiment in, according to short-range communication protocols (for example, IEEE 802.11a standards, IEEE 802.11n standards, IEEE 802.11ac standards etc.) provided in filling equation determine the number of filling bit.In general, these filling equatioies are related to And it is based partially on the number (NDBPS) and/or the number per symbolic coding data bit of every OFDM symbol data bit (NCBPS) number of filling bit, is calculated.According to embodiment, in scope mode of extension, in information bit by block encoder Before 1704 pieces of codings and BCC are encoded by FEC encoder 1706, the number (for example, 6 based on the information bit in OFDM symbol Individual bit, 12 bits, 13 bits etc.), determine the number of filling bit.Therefore, in scope mode of extension data cell Filling bit number substantially with the packing ratio of (or in corresponding short-range data unit) in corresponding conventional model data Special number is different.On the other hand, according to embodiment, in the number and normal mode data cell per character-coded bit The number of the every character-coded bit of (or in corresponding short-range data unit) is identical, for example, per OFDM24,48,52 etc. Deng coded-bit.

Figure 17 B are the example PHY processing units for formation range mode of extension data cell according to another embodiment 1750 block diagram.In certain embodiments, the signal of the formation range mode of extension data cell of PHY processing units 1750 and/or Data field.With reference to Fig. 1, in one embodiment, AP 14 and client stations 25-1 each includes PHY processing units, such as PHY Processing unit 1750.

In addition to FEC encoder 1706 is replaced by LDPC encoder 1756 in PHY processing units 1750, PHY processing units 1750 is similar with the PHY processing units 1700 of Figure 17 A.Therefore, in this embodiment, the output of block encoder 1704 is provided use Encode in the further block of LDPC encoder 1756.In embodiment, LDPC encoder 1756 is using the code rate with 1/2 Corresponding block coding or the block corresponding with another suitable code rate is encoded.In the illustrated embodiment, PHY process Unit 1750 omits interleaver 1710, is not required to because the adjacent bit in information flow is generally washed out by LDPC code itself Further to interweave.Additionally, in embodiment, by the LDPC tones unit 1760 that remaps further frequency point is provided Collection.According to embodiment, LDPC tones remap unit 1760 according to tone remap function pair coding information bit or The block of information bits of coding is resequenced.Usually, the function that remaps to tone is defined so that continuous coding Information bit or block of information bits be mapped on the discontinuous tone in OFDM symbol with promote during the transmission adversely Affect the data recovery at the receiver in the case of continuous OFDM tones.In certain embodiments, LDPC tone weights are omitted New mappings unit 1760.Fig. 7 A are referred again to, in various embodiments, some tail bits are commonly added to the every of data cell Individual field for FEC encoder 1706 appropriate operation, for example with guarantee to make BCC decoder encoded each field it After return to nought state.In one embodiment, for example, (for example, existed before data division is provided to FEC encoder 1706 After bit is processed by block encoder 1704), six tail bits are inserted at the ending of data division.

In certain embodiments, compared with the signal field form of normal mode data cell, scope mode of extension number There are different forms according to the signal field of unit.In some such embodiments, the signal with normal mode data cell Field compares, and the signal field of scope mode of extension data cell is shorter.For example, according to embodiment, only one is modulated and compiled Code scheme is used in scope mode of extension, and therefore is needed with regard to modulation and the less information for encoding (or without information) Transmit in scope mode of extension signal field.Similarly, in embodiment, compared with the maximum length of normal mode data cell Compared with, the maximum length of scope mode of extension data cell is shorter, and in this case, for scope mode of extension signal letters Less bit is needed for the Length subfield of section.As an example, in one embodiment, scope mode of extension signal field According to IEEE 802.11n standard formats, but omit some son field (for example, sub- words of low-density checksum (LDPC) Section, space-time block coding (STBC) son field etc.).Additionally or alternatively, in certain embodiments, with normal mode signal CRC (CRC) son field of field compares, and scope mode of extension signal field includes shorter CRC son fields (for example, less than 8 bits).In general, according to some embodiments, in scope mode of extension, omitting or changing some signals Field son field and/or add some fresh informations.

Figure 18 A are for use range extended coding schemes generation scope mode of extension data sheet according to another embodiment The block diagram of the example PHY processing unit 1800 of unit.In certain embodiments, the formation range mode of extension of PHY processing units 1800 The signal and/or data field of data cell.With reference to Fig. 1, in one embodiment, AP 14 and client stations 25-1 each include PHY processing units, such as PHY processing units 1800.

Except in addition to block encoder 1808 is positioned at after FEC encoder 1806 in PHY processing units 1800, PHY process is single Unit 1800 is similar with the PHY processing units 1700 of Figure 17 A.Therefore, in this embodiment, information bit is first by scrambler 1802 Scramble, encoded by FEC encoder 1806, and the bit of FEC codings is then replicated by block encoder 1808 or otherwise block is compiled Code.Such as in the example embodiment of PHY processing units 1700, in embodiment, to will generate whole field (for example, entirely Data division, whole signal field etc.) it is consecutively carried out the process of FEC encoder 1806.Therefore, in this embodiment, with The corresponding information bit of the field of generation is encoded first by FEC encoder 1806, and bit and then the division of BCC codings It is the block with specified size (for example, 6 bits, 12 bits, 13 bits or any other suitable number of bits).So Afterwards, each block is processed by block encoder 1808.As an example, in one embodiment, FEC encoder 1806 is using 1/2 Code rate coding is per the information bit of OFDM symbol 12 generating the bit of 24 BCC coding and carry the bit that BCC is encoded Supply block encoder 1808.In embodiment, block encoder 1808 generates each incoming piece two copy and according to scope Extended coding scheme by the Bit Interleave for being generated to generate OFDM symbol to be comprised in 48 bits.At one so Embodiment in, 48 bits are given birth to the Fast Fourier Transform (FFT) (FFT) using size 64 at IDFT processing units 1818 Into 48 data tones it is corresponding.Used as another example, in another embodiment, FEC encoder 1806 uses 1/2 coding Rate coding is per 6 information bits of OFDM symbol generating the bit of 12 BCC coding and be supplied to the bit that BCC is encoded Block encoder 1808.In embodiment, block encoder 1808 generates two copies of each input block and is extended according to scope Encoding scheme by the Bit Interleave for being generated to generate OFDM symbol to be comprised in 24 bits.It is real as one In applying example, 24 bits are relative with 24 data tones generated using the FFT of size 32 at IDFT processing units 1818 Should.

It is similar with the block encoder 1704 of Figure 17 A, depending on embodiment, by block encoder 1808 for formation range extension The scope extended coding scheme of the signal field of mode data unit is used for formation range mode of extension with by block encoder 1808 The scope extended coding scheme of the data division of data cell is identical or difference.In various embodiments, block encoder 1808 " block level " iteration scheme or " bit-level " iteration scheme are realized, as the block encoder 1704 above for Figure 17 A is discussed.Class As, in another embodiment, block encoder 1808 generates the copy of the m numbers of incoming bit and is incited somebody to action according to suitable code The bit stream of gained interweaves or otherwise encodes incoming bit or incoming bit block using any suitable code, for example, with 1/ 2nd, Hamming (Hamming) block code or any other block with 1/2,1/4 etc. code rate of 1/4 etc. code rate Code (for example, (1,2) or (Isosorbide-5-Nitrae) block code, (12,24) block code or (6,24) block code, (13,26) block code etc.).According to embodiment, The efficient coding speed of the data cell that PHY processing units 1800 are generated is the coding speed used by FEC encoder 1806 The product of the number (or code rate) of the repetition that rate and block encoder 1808 are used.

In embodiment, block encoder 1808 provides enough diversity gains so that the bit that need not be encoded enters one Step interweaves, thus omits interleaver 1810.An advantage for omitting interleaver 1810 is, in this case, even if one It is a little so in the case of, be not integer per the number of symbol data bit, it is also possible to generated using 4x or 6x iteration schemes and had The OFDM symbol of 52 data tones.For example, in one suchembodiment, the output of FEC encoder 1806 is divided into The block of 13 bits, and each block is repeated four times (or carrying out block coding with 1/4 speed) to generate OFDM to be comprised in symbol 52 bits in number.In this case, if FEC encoder 1806 utilizes 1/2 code rate, per symbol data ratio Special number is equal to 6.5.In the example embodiment repeated using 6x, FEC encoder 1806 is encoded using 1/2 code rate Information bit, and output is divided into the block of four bits.Block encoder 1808 repeats each four bit block six times and (or uses 1/ 6 code rate carries out block coding to each block) and add four filling bits to generate OFDM symbol to be comprised in 52 bits.

Such as in the example of the PHY processing units 1700 of Figure 17 A as discussed above, if filling is by PHY processing units 1800 use, then the number (NDBPS) of the every symbol data bit for calculating for filling bit is the nonredundancy in OFDM symbol Actual number (6 bits for example, such as in example above, 12 bits, 13 bits or any other is suitable of data bit Close the bit of number).It is equal to using the number of the every character-coded bit (NCBPS) in calculating in filling bit and is actually wrapped The number of the bit being contained in OFDM symbol (for example, is included in 24 bits, 48 bits, 52 bits in OFDM symbol Or any other suitable number of bit).

And, such as in the example of the PHY processing units 1700 of Figure 17, some tail bits are usually plugged into data sheet For the appropriate operation of FEC encoder 1806 in each field of unit, for example with guarantee to make BCC decoder encoding it is every Nought state is returned to after individual field.In one embodiment, for example, before data division is provided to FEC encoder 1806 (that is, after the process for performing block encoder 1704), six tail bits are inserted at the ending of data division.It is similar Ground, according to embodiment, in the case of signal field, before signal field is provided to FEC encoder 1806, by tail bits At the ending of insertion signal field.Wherein block encoder 1808 using 4x iteration schemes (or with the another of 1/4 code rate One block code) example embodiment in, FEC encoder 1806 using 1/2 code rate, and signal field include 24 information 24 signal field bits are carried out BCC and are encoded to generate the bit of 48 BCC codings by bit (including tail bits), these Then bit is divided into four blocks of respective 12 bit for further being encoded by block encoder 1808.Therefore, in the embodiment In, signal field is sent by four OFDM symbols, and each includes 6 information bits of signal field.

In addition, in certain embodiments, PHY processing units 1800 are according to IEEE 802.11n standards or IEEE The MCS0 of defined in 802.11ac standards, generates the OFDM symbol with 52 data tones, and block encoder 1808 is sharp Use 4x iteration schemes.In some such embodiments, extra padding is employed to ensure that the institute in OFDM symbol to be comprised in The data flow of the coding for obtaining includes 52 bits.In one suchembodiment, in bit via block encoder 1808 at After reason, filling bit is added to the information bit of coding.

In the embodiment of Figure 18 A, PHY processing units 1800 also include that papr (PAPR) reduces unit 1809.In embodiment, PAPR reduces unit 1809 and makes the bit reversal in the block of some or all repetitions to reduce or eliminate The generation of the same bits sequence at different frequency position in OFDM symbol, so as to reduce the peak-to-average power of output signal Than.In general, bit reversal is related to by the bit value of zero bit value change to one and by one bit value change to zero Bit value.According to embodiment, PAPR reduces unit 1809 and realizes bit reversal using xor operation.For example, encoding ratio is being utilized In the embodiment that the 4x of special block repeats, if being represented as C and such as including the block of the coded-bit in OFDM symbol Fruit C'=C XOR 1 (that is, the block C of the bit with upset), then according to some embodiments, PAPR reduces the defeated of unit 1809 The possible bit sequence of some of source is [C C'C'C'], [C'C'C'C], [C C'C C'], [C C C C'] etc.. Generally speaking, it is possible to use any combinations of the block of the bit with upset and the block with unturned bit.In some realities In applying example, PAPR units 1809 are omitted.

Figure 18 B are the example PHY processing units for formation range mode of extension data cell according to another embodiment 1850 block diagram.In certain embodiments, the signal of the formation range mode of extension data cell of PHY processing units 1850 and/or Data field.With reference to Fig. 1, in one embodiment, AP 14 and client stations 25-1 each includes PHY processing units, such as PHY Processing unit 1850.

In addition to FEC encoder 1806 is replaced by LDPC encoder 1856 in PHY processing units 1850, PHY processing units 1850 is similar with the PHY processing units 1800 of Figure 18.Therefore, in this embodiment, information bit is first by LDPC encoder 1856 codings, and the bit of LDPC codings is then replicated by block encoder 1808 or otherwise block is encoded.In embodiment, LDPC encoder 1856 is encoded or corresponding with another suitable code rate using the corresponding block of the code rate with 1/2 Block is encoded.In the illustrated embodiment, PHY processing units 1850 omit interleaver 1810, because the adjacent ratio in information flow It is special generally by LDPC code itself be washed out thus according to embodiment, it is not necessary to further intertexture.Additionally, in embodiment, Further frequency diversity is provided by the LDPC tones unit 1860 that remaps.According to embodiment, LDPC tones remap Unit 1860 is resequenced according to the remap block of information bits of function pair coded information bits or coding of tone.It is logical Often, the function that remaps to tone is defined so that the information bit or block of information bits of continuous coding is mapped to OFDM Promoting to negatively affect reception in the case of continuous OFDM tones during the transmission on discontinuous tone in symbol Data recovery at device.In certain embodiments, omit LDPC tones to remap unit 1860.

Figure 19 A are the example PHY processing units for formation range mode of extension data cell according to another embodiment 1900 block diagram.In certain embodiments, the signal of the formation range mode of extension data cell of PHY processing units 1900 and/or Data field.With reference to Fig. 1, in one embodiment, AP 14 and client stations 25-1 each includes PHY processing units, such as PHY Processing unit 1900.

Except in addition to block encoder 1916 is positioned at after constellation mapper 1914 in PHY processing units 1900, PHY process is single Unit 1900 is similar with the PHY processing units 1800 of Figure 18 A.Therefore, in this embodiment, the information bit of BCC codings is Constellation symbol is mapped to after being processed by interleaver 1910, and constellation symbol and then replicated by block encoder 1916 or otherwise block Coding.According to embodiment, connect on by the whole field (for example, whole data field, whole signal field etc.) for generating The process of FEC encoder 1906 is performed continuously.In this embodiment, the information bit corresponding with the field for being generated first by FEC encoder 1806 is encoded, and then the bit of BCC codings is mapped to constellation symbol by constellation mapper 1914.Constellation is accorded with Number then be divided into specified size (for example, 6 symbols, 12 symbols, 13 symbols or any other suitable number of symbols Number) block and each block and then processed by block encoder 1916.As an example, in the embodiment repeated using 2x, constellation Mapper 1914 generates 24 constellation symbols, and block encoder 1916 generates two copies of 24 symbols to generate and OFDM 48 corresponding symbols of 48 data tones of symbol (for example, as specified in IEEE 802.11a standards).As Another example, in the embodiment repeated using 4x, constellation mapper 1914 generates 12 constellation symbols, and block encoder 1916 generate four copies of 12 constellation symbols to generate 48 symbols corresponding with the 48 of OFDM symbol data tones (for example, such as the defined in IEEE 802.11a standards).As another example, in the embodiment repeated using 2x, star Seat mapper 1914 generates 26 constellation symbols, and block encoder 1916 repeats 26 symbols and (that is, generates the two of 26 symbols Individual copy) (for example, such as marked in IEEE 802.11n with the 52 of OFDM symbol 52 corresponding symbols of data tones with generating Accurate or IEEE 802.11ac prescribed by standard).In general, in various embodiments and/or scene, block encoder 1916 Generate any suitable number of copy of the block of incoming constellation symbol and according to any suitable encoding scheme to being generated Symbol is interleaved.It is similar with the block encoder 1808 of the block encoder 1704 of Figure 17 A and Figure 18 A, depending on embodiment, by block Encoder 1916 is used for the scope extended coding of (one or more) signal field of formation range mode of extension data cell Scheme with by block encoder 1916 be used for formation range mode of extension data cell data division scope extended coding scheme Identical or difference.According to embodiment, the efficient coding speed of the data cell generated by PHY processing units 1900 is FEC The product of the number (or code rate) of the repetition that the code rate and block encoder 1916 that encoder 1906 is used is used.

According to embodiment, because in this case, redundancy is introduced after information bit has been mapped into constellation symbol, So compared with the OFDM data tone being included in normal mode data cell, being generated by PHY processing units 1900 Each OFDM symbol includes less Non-redundant data tone.Therefore, (such as scheme with the interleaver used in normal mode 16 interleaver 1610) or compare the interleaver used in corresponding short-range data unit is generated, interleaver 1910 It is designed to the tone less to every OFDM symbol to operate.For example, with per 12 Non-redundant data sounds of OFDM symbol In the embodiment of tune, interweaved using 6 columns (Ncol) and line number (Nrow) design of 2* every subcarrier bit numbers (Nbpscs) Device 1910.In with another example embodiment per 12 Non-redundant data tones of OFDM symbol, the columns and 3* using 4 The Nrow design interleavers 1910 of Nbpscs.In other embodiments, with the interleaver parameter used in normal mode not Other same interleaver parameters are used for interleaver 1910.Alternatively, in embodiment, block encoder 1916 provides enough dividing Diversity gain so that the further intertexture of the bit that need not be encoded, thus omit interleaver 1910.In this case, such as exist In example embodiment using the PHY processing units 1800 of Figure 18 A, even if in the case of some are such, per symbol data ratio Special number is not integer, it is also possible to the OFDM symbol with 52 data tones is generated using 4x or 6x iteration schemes.

Example such as in the PHY processing units 1800 of the PHY processing units or Figure 18 A of Figure 17 A as discussed above is implemented In example, if filling is used by PHY processing units 1900, the number (NDBPS) calculated for filling bit is OFDM symbol In Non-redundant data bit actual number (6 bits for example, such as in example above, 12 bits, 13 bits or Any other suitable number of bit).The number (NCBPS) of the every character-coded bit used in filling bit is calculated Equal to the number of the nonredundancy bit being included in OFDM symbol, its in this case with the star processed by block encoder 1916 The number (for example, 12 bits, 24 bits, 26 bits etc.) of the bit in the block of seat symbol is corresponding.

In certain embodiments, PHY processing units 1900 are according to IEEE 802.11n standards or IEEE 802.11ac standards The MCS0 of middle defined, generates the OFDM symbol with 52 data tones, and block encoder 1916 utilizes 4x iteration schemes. In some such embodiments, extra padding is employed to ensure that the data of the coding of the gained in OFDM symbol to be comprised in Stream includes 52 bits.In one suchembodiment, after bit is processed via block encoder 1808, filling bit It is added to the information bit of coding.

In the embodiment of Figure 19, PHY processing units 1900 include that papr (PAPR) reduces unit 1917. In embodiment, papr unit 1917 is by some data tones in the data tones for repeating constellation modulation Addition phase offset.For example, in one embodiment, the phase offset of addition is 180 degree.180 degree phase offset and bit Symbol upset is corresponding, and the data tones of phase offset are realized in its modulation.In another embodiment, PAPR reductions unit 1917 adds Plus the phase offset (for example, 90 degree phase offsets or any other suitable phase offset) different from 180 degree.As an example, In the embodiment repeated using 4x, if the block of 12 constellation symbols in OFDM symbol to be comprised in is represented as C simultaneously And if performing single piece of repetition, then the sequence of gained is [C C C C].In certain embodiments, PAPR reduces unit 1917 For some block created symbols upset (that is ,-C) in the block of repetition or 90 degree of phase offsets (that is, j*C).As some In embodiment, the sequence of gained is such as [C-C-C-C], [- C-C-C-C], [C-C C-C], [C C C-C], [C J*C, j*C, j*C] or C ,-C, j*C and-j*C any other combination.In general, in various embodiments and/or scene, Any suitable phase offset can be introduced in the block of any repetition.In certain embodiments, omitting PAPR reduces unit 1809。

In certain embodiments, PHY processing units 1900 are according to IEEE 802.11n standards or IEEE 802.11ac standards The MCS0 of middle defined, generates the OFDM symbol with 52 data tones, and block coding 1916 utilizes 4x iteration schemes. In some such embodiments, extra pilots tone is inserted with the data tones and pilot tones in the OFDM symbol for guaranteeing gained Number be equal to 56, such as the defined in short-range communication protocols.As an example, in embodiment, with 1/2 code rate Six information bits are carried out with BCC codings, and 12 bit maps of gained to 12 constellation symbols (BPSK).12 constellations 12 data tones of symbol-modulated, then it be repeated four times, and generates 48 data tones.Such as the institute in IEEE 802.11n standards Regulation, add four pilot tones, and add 4 extra pilots tones to generate 56 data and pilot tones.

Figure 19 B are the example PHY processing units for formation range mode of extension data cell according to another embodiment 1950 block diagram.In certain embodiments, the signal of the formation range mode of extension data cell of PHY processing units 1950 and/or Data field.With reference to Fig. 1, in one embodiment, AP 14 and client stations 25-1 each includes PHY processing units, such as PHY Processing unit 1950.

In addition to FEC encoder 1906 is replaced by LDPC encoder 1956 in PHY processing units 1950, PHY processing units 1950 is similar with the PHY processing units 1900 of Figure 19.Therefore, in this embodiment, the information bit of LDPC codings is reflected by constellation Emitter 1914 is mapped to constellation symbol and constellation symbol is then replicated by block encoder 1916 or otherwise block is encoded.In embodiment In, LDPC encoder 1956 is using the corresponding block coding or relative with another suitable code rate of the code rate with 1/2 The block coding answered.In the illustrated embodiment, PHY processing units 1950 omit interleaver 1910, because the phase in information flow Adjacent bit generally by LDPC codes itself be washed out thus according to embodiment, it is not necessary to it is further to interweave.Additionally, implementing In example, by the LDPC tones unit 1960 that remaps further frequency diversity is provided.According to embodiment, LDPC tones are again Map unit 1960 is arranged again according to the remap information bit or the block of information bits of coding of function pair coding of tone Sequence.Generally, the function that remaps to tone is defined so that the information bit or block of information bits of continuous coding is mapped to In the case of continuous OFDM tones being negatively affected during the transmission on discontinuous tone in OFDM symbol with promotion Data recovery at receiver.In certain embodiments, omit LDPC tones to remap unit 1960.

In with regard to Figure 17-19 embodiments described above, scope mode of extension by repeat frequency domain in bit and/ Or constellation symbol introduces redundancy.Alternatively, in certain embodiments, scope extended coding scheme includes the model for performing in the time domain The OFDM symbol of the signal and/or data field that enclose mode of extension data cell repeats.For example, Figure 20 A are according to embodiment Illustrate scope mode of extension data cell it is leading in HT-SIG1 and HT-SIG2 fields each OFDM symbol 2x repeat. Similarly, Figure 20 B be according to embodiment illustrate scope mode of extension data cell it is leading in L-SIG fields each The 2x of OFDM symbol repeats.Figure 20 C are in the data division illustrated for control model data cell according to one embodiment OFDM symbol time domain iteration scheme diagram.Figure 20 D are according with for the OFDM in data division according to another embodiment Number iteration scheme diagram.As indicated, in the embodiment of Figure 20 C, continuously output OFDM symbol repeats, and in Figure 20 D Embodiment in, OFDM symbol repeat be interweave.In general, in various embodiments and/or scene, being adapted to according to any Interleaving scheme, intertexture OFDM symbol repeat be.

Figure 21 is the flow chart for generating the exemplary method 2100 of data cell according to embodiment.With reference to Fig. 1, in reality In applying example, by the implementation method 2100 of network interface 16.For example, in one suchembodiment, PHY processing units 20 are matched somebody with somebody It is set to implementation method 2100.According to another embodiment, MAC processes 18 at least a portion for being also arranged to implementation method 2100. With continued reference to Fig. 1, in another embodiment, by network interface 27 (for example, PHY processing units 29 and/or MAC processing units 28) implementation method 2100.In other embodiments, by other suitable network interface implementation methods 2100.

At block 2102, according to block code, the information bit to being comprised in data cell is encoded.For example, In one embodiment, encoded using the 1704 as described above pieces of levels of block encoder or bit-level iteration scheme with regard to Figure 17 Information bit.At block 2104, information bit is encoded using FEC encoder, such as the FEC encoder of Figure 17 A The LDPC encoder 1756 of 1706 or Figure 17 B.At block 2106, information bit is mapped to constellation symbol.It is raw at block 2108 Into the multiple OFDM symbols including constellation point.At block 2110, generation includes the data cell of OFDM symbol.

In one embodiment, as illustrated in figure 21, information bit encodes (block first by block encoder 2102), and block coding bit then using FEC encoder encode (block 2104), such as retouched above with regard to Figure 17 A State.In another embodiment, the order of block 2102 and 2104 is to exchange.Therefore, in this embodiment, first to information ratio Spy carries out FEC codings, and the bit that FEC is encoded is encoded according to block encoding scheme, such as with regard to Figure 18 A above Described.In another embodiment, block 2102 is positioned at after block 2106.In this embodiment, to information at block 2104 Bit carries out FEC codings, at block 2106 by FEC encode bit map to constellation symbol, and and then at block 2102 root It is such as described above with regard to Figure 19 A according to block coding or iteration scheme encoding constellation symbol.

In various embodiments, scope extended coding scheme uses Fast Fourier Transform (FFT) (FFT) technology for reducing size, The constellation symbol of the reduction number that its output repeats in total bandwidth is with improvement threshold and/or SNR performances.For example, implementing In example, constellation mapper is mapped to bit sequence and 32 subcarrier (for example, 32-FFT moulds with 24 data tones Formula) corresponding multiple constellation symbols.32 subcarriers are corresponding with the 10MHz sub-bands of total 20MHz bandwidth.In this example, Total bandwidth across 20MHz repeats constellation symbol to provide the redundancy of constellation symbol.In various embodiments, size is reduced FFT technique be applied in combination with regard to Figure 17-19 step-by-step duplications as described above and/or symbol reproduction technology.

Some enforcements of additional bandwidth available (40MHz, 80MHz, 160MHz, 320MHz, 640MHz etc.) wherein In example, across each 10MHz sub-band of total bandwidth 32 subcarriers are repeated.For example, in another embodiment, 32-FFT patterns with The 5MHz sub-bands of total 20MHz bandwidth are corresponding.In this embodiment, across total 20MHz bandwidth (that is, in each 5MHz sub-band In) multiple constellations are repeated into 4x.Therefore, receiving device by multiple constellation combinations improving the decoding reliability of constellation.At some In embodiment, the modulation of different 5MHz or 10MHz sub-band signals rotates different angles.For example, in one embodiment, First sub-band rotates 0 degree, and the second sub-band is rotated by 90 °, the 3rd sub-band rotation 180 degree, and the 4th sub-band rotates 270 degree.In other embodiments, using different suitable rotations.In at least some embodiments, 20MHz sub-band signals Out of phase cause reduce data cell in OFDM symbol papr (PAPR).

Figure 22 A are that the 20MHz that the 2x of the scope growth data unit with 10MHz sub-bands according to embodiment repeats is total The diagram of bandwidth.As shown in FIG. 22 A, each sub-band of 10MHz correspondingly rotates r1 and r2.Figure 22 B are according to embodiment The scope growth data unit with 10MHz sub-bands 4x repeat 40MHz total bandwidths diagram.As shown in Figure 22 B, Each subband width of 10MHz correspondingly rotates r1, r2, r3 and r4.Figure 22 C are relative with 10MHz sub-bands according to embodiment The diagram of the example tone planning 2230 of the 32-FFT patterns answered.Tone planning 2230 includes 32 total tones, and it has 24 Data tones, 2 pilot tones at the place of index+7 and -7,1 direct current tone and 5 protection tones, as shown in Figure 22.At it Used in reduce size FFT technique embodiment in, the planning of corresponding tone is used for HEW-LTF fields (when it is present). Wherein using the size FFT technique for reducing but in the non-existent other embodiment of HEW-LTF fields, L-LTF fields are changed 704 respective index to plan to modified tone comprising ± 1 additional symbol for pilot tones.For example, implementing In example, tone -29, -27 ,+27 and+29 is added to the tone planning for L-LTF fields.In another embodiment, from 20MHz L-LTF tones planning in tone -2, -1,1 and 2 in bandwidth removes ± 1 symbol.It is similar change be suitable to 40MHz, 80MHz, The total bandwidth of 160MHz etc..

Figure 23 is data cell is used for according to the wherein scope mode of extension of embodiment leading 2301 sample data The diagram of unit 2300.In certain embodiments, leading 2301 both normal mode and scope mode of extension are indicated.Such In embodiment, using the other method for distinguishing normal mode and scope mode of extension, such as with regard to the institute above of Fig. 9,10 and 11 Those of description.

In addition to leading the 2301 of data cell 2300 are formatted differently with leading the 1151 of data cell 1101, data sheet Unit 2301 is substantially similar with the data cell 1150 of Figure 11 B and including the element equally numbered with it.In embodiment, to front Lead 2301 to be formatted so that can determine that leading 2301 is scope extension according to the receiving device of HEW communication protocol operations Pattern is leading rather than normal mode is leading.In embodiment, compared with data cell 1151, leading 2301 are included correspondingly Replace modified long training field M-LTF 2304 and modified signal field M-SIG of L-LTF 704 and L-SIG 706 2306.In embodiment, leading 2301 include L-STF 702, are followed by and train sequence as the modified long of M-LTF 2304 The double protection interval of two repetitions of row, normal protection interval and modified signal field M-SIG.In some embodiments In, leading 2301 also include one or more HEW signal fields (HEW-SIGA) 1152.In embodiment, leading 2301 Also include following one or more secondary M-SIG1154 of L-SIG fields 2306.In certain embodiments, (one or more) Secondary L-SIG is followed by the 2nd L-LTF fields (L-LTF2) 1156.In other embodiments, (one more for leading 2301 omission It is individual) L-SIG 1154 and/or L-LTF2 1156.In certain embodiments, leading 2301 also include HEW-STF 1158, Or multiple HEW signal fields (HEW-SIGB) 1162 of HEW-LTF fields 1160 and the 2nd.In other embodiments, leading 2301 Omit HEW-STF 1158, (one or more) HEW-LTF 1160 and/or HEW-SIGB 1162.In embodiment, data sheet Unit 2300 also includes data division 716 (not shown in fig 23).In certain embodiments, using identical with data field 716 Scope extended coding modulating scheme HEW signal fields (HEW-SIGA) 1152.

In various embodiments, M-LTF 2304 is multiplied by predetermined sequence (for example, polarization code) corresponding to L-LTF 704.Example Such as, using index i, i-th constellation symbol of L-LTF 704 be multiplied by i-th value of predetermined sequence (for example, ± 1) to obtain M- LTF 2304, as illustrated in equation 1：

M-LTF_i=C_i*L-LTF_i(equation 1)

Wherein, C is predetermined sequence.In certain embodiments, M-SIG 2306 is multiplied by pre- sequencing corresponding to L-SIG 706 Row, as shown in Equation 2：

M-SIG_i=C_i*L-SIG_i(equation 2)

In certain embodiments, the length (that is, the number of value) of predetermined sequence is equal to the number and IEEE of data tones The number sum of the pilot tones in 802.11ac agreements per 20MHz frequency bands, such as 52 values are (that is, for 48 data tones With 4 pilot tones).

In embodiment, predetermined sequence and modified long training sequence each have the number for being more than or equal to data tones The length of the number sum of mesh and pilot tones.Such as plan with regard to the tone of the 32-FFT pattern corresponding with 10MHz sub-bands 2230 and it is as described above, if HEW-STF and/or HEW-LTF fields be not present in scope extension it is leading in, receiver Depend on the L-LTF fields for the demodulation of follow-up field.In embodiment ,+1 or -1 symbol is inserted by the tone for losing Enter in L-LTF to correct the planning mismatch of the tone between 20MHz-LTF and 10MHz 32-FFT patterns (for example, for total 58 For individual tone, tone -29, -27 ,+27 and+29).

Figure 24 is the example PHY processing unit for formation range mode of extension data cell according to another embodiment 2400 block diagram.In certain embodiments, the signal of the formation range mode of extension data cell of PHY processing units 2400 and/or Training field.With reference to Fig. 1, in one embodiment, AP 14 and client stations 25-1 each includes PHY processing units, such as PHY Processing unit 2400.

In addition to being positioned at after constellation mapper 1614 in the medium pitch multiplier 2404 of PHY processing units 2400, PHY process Unit 2400 is similar with the PHY processing units 1700 of Figure 17 A.In certain embodiments, tone multiplier 2404 is generated and i) is directed to The modified constellation symbol and ii of the L-SIG fields (that is, M-SIG 2306) of scope mode of extension data cell) it is directed to scope The modified long training sequence of the L-LTF fields (that is, M-LTF 2304) of mode of extension data cell.

In certain embodiments, PHY processing units 2400 are configured at least through by predetermined sequence and the second communication protocols Second long training sequence of view is multiplied, and generates for the first leading long training sequence of scope mode of extension.In embodiment, example Such as, predetermined sequence is multiplied by L-LTF 704 to obtain M-LTF 2304 by tone multiplier 2404.In embodiment, expand in scope Replace L-LTF 704, tone multiplier 2404 that M-LTF 2304 is supplied into IDFT 1618 during exhibition pattern.

In embodiment, tone multiplier 2404 is received from constellation mapper 1614 and is directed to L-SIG to be comprised in 706 In data constellation symbol, and from pilot tones generator 2408 receive for pilot tones constellation symbol.Therefore, exist In embodiment, the M-SIG 2306 exported from tone multiplier 2404 is included for treating to be converted to time domain letter by IDFT 1618 Number data tones and pilot tones modified constellation symbol.

In certain embodiments, receiver apparatus for example use the channel estimation for being based on M-LTF 2304 to M-SIG 2306 Decoded.In this example, because L-LTF 704 and L-SIG 706 have been multiplied by predetermined sequence, legacy receiver sets It is standby to effectively remove the multiplication as channel estimation process or a part for autocorrelation process.In embodiment, receiving device leads to Cross be multiplied with predetermined sequence based on L-LTF fields and the auto-correlation that is not multiplied and detect it is having (for example, be multiplied by) predetermined sequence Still generate in the case of not being multiplied by predetermined sequence it is leading in LTF fields (for example, either M-LTF 2304 or L-LTF 704), determine that leading is that leading with scope mode of extension 2400 or normal mode are leading 1101 corresponding.In embodiment, connect Receiving unit performs first auto-correlation of LTF and L-LTF 704, performs second auto-correlation of LTF and M-LTF 2304 and performs The comparison of autocorrelation result.In embodiment, if the auto-correlation generation and oneself with regard to L-LTF 704 with regard to M-LTF 2304 Related result compares larger result, then receiving device determines that leading leading with scope mode of extension 2300 is corresponding.Separately On the one hand, in embodiment, if the auto-correlation of LTF and L-LTF 704 is produced and the autocorrelative knot with regard to M-LTF 2304 Fruit compares larger result, then receiving device determines that leading leading with normal mode 1101 is corresponding.In certain embodiments, Receiver apparatus perform the auto-correlation in frequency domain according to equation 3：

Wherein, y_iBe it is last receive and average L-LTF sequences, L_iBe transmitted belong to IEEE 802.11a/ The L-LTF sequences of n/ac or modified long training sequence M-LTF.For example, L_iIt is the C for scope mode of extension_i*L- LTF_iOr being the L-LTF for normal mode_i.In some scenes, the cross correlation of continuous tone generally removes channel Effect, and most probable transmission sequence is found in frequency matching filtering.In certain embodiments, receiver apparatus are used from M- The channel estimation of LTF carrys out the added field (that is, HEW-SIG and/or data field) of decoding data unit.In some scenes, The value of the predetermined sequence corresponding with pilot tones is entirely one, and this allows the Phase Tracking on pilot tones.

In certain embodiments, the OFDM modulation with the tone spacing for reducing is used together to subtract with formed objects FFT Data rate in few scope mode of extension.For example, it is fast using 64 points for the normal mode of 20MHz bandwidth OFDM data units Fast Fourier transformation (FFT), produces 64 OFDM tones；Scope mode of extension is produced using by the therefore 2 tone spacing for reducing 128 OFDM tones in same band.In this case, with the symbol increased using identical 64 point FFT, 2x continue when Between with 2x increase protection interval when normal mode OFDM symbol compare, the tone spacing in scope mode of extension OFDM symbol (1/2) is reduced with the factor 2, wherein, the then replicator in remaining bandwidth.As another example, for 20MHz bandwidth OFDM The normal mode of data cell converts (FFT) using 64 point quick Fouriers, 64 OFDM tones of generation；Scope mode of extension Using the tone spacing of 1/4 reduction for 20MHz OFDM data units, 256 MHz OFDM sounds in same band are produced Adjust.In this case, with normal mode OFDM during the protection interval increased in the symbol duration and 4x increased using 4x Symbol compares, and the tone spacing in scope mode of extension OFDM symbol is reduced (1/4) with the factor 4.In such embodiments, Using the long GI duration of such as 1.6 μ s.However, in embodiment, the message part of scope mode of extension OFDM symbol Duration increased (for example, from 3.2 μ s of μ s to 6.4), and GI section durations and total OFDM symbol duration Percentage keeps identical.Therefore, in this case, at least some embodiments, it is to avoid be attributed to longer GI symbols Loss in efficiency.In various embodiments, as used herein term " long protection interval " covers holding for the increase of protection interval The continuous time and be effectively increased protection interval duration and the OFDM tone spacing that reduces.In other embodiments, tone Spacing is reduced, and protection interval increases and symbol duration increases according to the factor of 6,8 or other suitable values.In some realities Change and block coding repetition symbol repeated combinations in applying example, in tone spacing, protection interval and symbol duration Use, as described above.

In certain embodiments, it is 20MHz for the resultant signal bandwidth of the data cell of scope mode of extension.For example, increase Plus signal bandwidth it is unlikely it is further increase scope or improve SNR performances.In certain embodiments, scope mode of extension quilt It is configured so that up to 512 points of FFT sizes.In such embodiments, if tone spacing for scope mode of extension with The factor 4 is reduced, then for the total bandwidth of 512FFT be 40MHz, therefore scope mode of extension is using reaching 40MHz signal bandwidths.

In other embodiments, (for example, scope mode of extension is arranged to up to maximum available signal bandwidth 160MHz).In various embodiments, for example, 1/2 tone spacing with for 10MHz frequency bands 64FFT, for 20MHz frequency bands 128FFT, the 256FFT for 40MHz frequency bands, the 512FFT for 80MHz frequency bands and the 1024FFT phases for 160MHz frequency bands Correspondence.In certain embodiments, the tone spacing of reduction combines less FFT sizes and uses.In various embodiments, it is shorter Protection interval is used together with the tone spacing for reducing, and for example, normal protection interval has the duration equal to OFDM symbol 25% duration, and short protection interval have equal to OFDM symbol 1/9 duration.

In certain embodiments, scope mode of extension uses less tone spacing (that is, 1/2,1/4 etc.).So Embodiment in, identical FFT sizes represent less bandwidth, and for example, 1/2 tone spacing is relative with the 64FFT on 10MHz frequency bands Should.In embodiment, the tone of identical FFT sizes is planned for scope mode of extension and normal mode are identicals, for example, model 64FFT in mode of extension is enclosed using planning with identical tone in the 64FFT of the 20MHz in IEEE 802.11ac.Figure 25A is the diagram of the example 20MHz total bandwidth with 1/2 tone spacing according to embodiment.In this case, for each The index of the original DC tones for leaving tone planning of 64FFT is now in the centre of 10MHz rather than in total 20MHz bandwidth Between, and for the original index for protecting tone be close to true DC tones.It is used for scope mode of extension data cell wherein In some embodiments of frequency band less than 20MHz, the planning of non-legacy tone includes the additional number at the index for original DC tones According to or pilot tones because index will not be Chong Die with " true DC tones " because minimum signal bandwidth be for scope extension The 20MHz of pattern or normal mode.In certain embodiments, non-legacy tone planning includes the edge for replacing leaving tone planning Place protects the additional data tone of tone to keep equal number of filling tone.

In other embodiments, when tone spacing is reduced, from direct current offset and carrier shift (CFO) impact with it is normal Scale formula is compared and become much larger.Figure 25 B are the diagrams of the example 20MHz total bandwidth with 1/2 tone spacing according to embodiment. In certain embodiments, with the identical FFT sizes in normal mode leave tone planning compared with, be close to for scope extension The direct current tone of the frequency band of the non-legacy tone planning of pattern defines additional zero tone.In various embodiments, additional zero tone Predetermined FFT sizes and/or tone spacing are only defined more than, for example, FFT sizes are big in the case of reducing 1/2 in tone spacing In or during equal to 128 or when FFT sizes are more than or equal to 256 in the case of reducing 1/4 in tone spacing.In some embodiments In, increase number protection tone be used for for scope mode of extension non-legacy tone plan, with for example maintain with normally The tone of leaving of pattern plans the absolute guard space (for example, absolute frequency space) compared at identical band edge.At this In the case of kind, the total number of data tones and pilot tones in the planning of non-legacy tone is planned less than tone is left.At some In example, identical absolute guard space promotes wave filter design.In certain embodiments, for example, wherein, for non-legacy tone The total number of the data tones of planning is not used in FFT sizes identical with normal mode, for the data of non-legacy tone planning The number of tone redefines the PHY parameters for FEC interleavers and/or LDPC tone mappers.

Figure 26 A are the non-something lost for the scope mode of extension with the tone spacing of FFT sizes 64 and 1/2 according to embodiment Stay the diagram of tone planning 2600.Non-legacy tone planning 2600 in, with for normal mode leave tone plan compared with, Contain supplementary protection tone (that is, protecting tone -28, -27 ,+27 ,+28).In certain embodiments, lead or 64FFT is utilized Or frequency-modulated audio tone data tones fill DC tones.Figure 26 B are for between the tone of FFT sizes 128 and 1/2 according to embodiment Away from scope mode of extension non-legacy tone planning 2601 diagram.It is conventional with being directed in non-legacy tone planning 2601 The tone planning of leaving of pattern compares, and contains additional protection tone (that is, protecting tone -58, -57 ,+57 ,+58) and attached Plus DC tones (that is, DC tones -2, -1,0,1,2).Figure 26 C are to be used for having the He of FFT sizes 256 according to the diagram of embodiment The diagram of the non-legacy tone planning 2602 of the scope mode of extension of 1/2 tone spacing.In non-legacy tone planning 2602, with Tone planning of leaving for normal mode is compared, including additional protection tone (that is, protect tone -122, -121 ,+121 ,+ 122) with additional DC tones (that is, DC tones -2, -1,0,1,2).In other embodiments, compared with normal mode, additional guarantor Shield tone and/or DC tones are added to the non-legacy tone planning for scope mode of extension.

Figure 27 is the flow chart for generating the exemplary method 2700 of data cell according to embodiment.With reference to Fig. 1, in reality In applying example, by the implementation method 2700 of network interface 16.For example, in one suchembodiment, PHY processing units 20 are matched somebody with somebody It is set to implementation method 2700.According to another embodiment, MAC processes 18 at least a portion for being also arranged to implementation method 2700. With continued reference to Fig. 1, in another embodiment, by network interface 27 (for example, PHY processing units 29 and/or MAC processing units 28) implementation method 2700.In other embodiments, by other suitable network interface implementation methods 2700.

At block 2702, the first OFDM symbol for data field is generated.In various embodiments, give birth at block 2702 Include according to the scope extended coding scheme or with normal mode corresponding corresponding with scope mode of extension into OFDM symbol One of conventional encoding scheme, generates the OFDM symbol of data division.In embodiment, scope extended coding scheme is included with regard to figure 10 scope extended coding schemes (for example, the tone spacing of reduction) as described above.In another embodiment, scope extension is compiled Code scheme is included with regard to Figure 17-20 scope extended coding schemes as described above (such as step-by-step repeats or symbol repeats). In another embodiment, scope extended coding scheme is included with regard to Figure 22 scope extended coding schemes as described above (for example, number Repeat according to unit).In another embodiment, scope extended coding scheme includes being retouched above with regard to Figure 10, Figure 17-20 and Figure 22 The suitable combination of the scope extended coding scheme stated.

In embodiment, accorded with according to OFDM of the scope extended coding schemes generation for the data division of PHY data unit Number include：(for example, FEC encoder 1706,1806 or 1906) multiple information bits are entered using forward error correction (FEC) encoder Row encodes to obtain the bit of multiple codings；The bit map of multiple codings is arrived using such as constellation mapper 1614 or 1914 Multiple constellation symbols；The OFDM symbol comprising multiple constellation symbols is generated using such as IDFT 1618 or 1818.In embodiment In, generating OFDM symbol also includes performing one below：I) encode multiple information bits according to block encoding scheme (for example, to use Block encoder 1704), ii) according to block encoding scheme (for example, using block encoder 1808) encode multiple codings bit or Iii) multiple constellation symbols are encoded according to block encoding scheme (for example, using block encoder 1916).In another embodiment, generate For the OFDM symbol of data field multiple constellation symbols being included in the first portions of bandwidth of channel width and will be many The copy of individual constellation symbol is included in the second portions of bandwidth of channel width, for example, such as described above with regard to Figure 22. In another embodiment, the copy of multiple constellation symbols is generated to offset including predetermined phase.

At block 2704, the leading of data cell is generated.It is leading to indicate in block that generation is generated at block 2704 At least data division of the data cell generated at 2702 be use range extended coding scheme or conventional encoding scheme and Generate.In various embodiments and/or scene, at block 1604 one of the following is generated：Leading 701 (Fig. 9 A, 10A), 751 (Fig. 9 B, 10B), 1101 (Figure 11 A), 1151 (Figure 11 B) or 1401 (Figure 14 A).In other embodiments, at block 2704 Generate other suitable leading.

In embodiment, generate leading so that with i) Part I, it indicates the duration of PHY data unit and ii) Part II, it indicates whether some OFDM symbols according to scope extended coding schemes generation at least data division.Another In embodiment, leading Part I is formatted so that leading Part I is by meeting the second communication protocol (example Such as, legacy communication protocols) but do not meet the receiver apparatus decodable code of the first communication protocol (for example, HEW communication protocols) with The duration of PHY data unit is determined based on leading Part I.

In embodiment, what is generated at block 2704 is leading including CI instruction collection, and it indicates that at least data division is to make Generated with scope extended coding scheme or normal encoding scheme.In embodiment, CI indicates to include a bit.Implementing In example, in addition to data division, indicate that indicated encoding scheme generates a leading part using by CI.In another embodiment In, leading it is formatted to what is generated at block 2704 so that receiving device can be automatically detected (for example, not to be had In the case of decoding) it is leading be leading with normal mode or leading with scope mode of extension corresponding.In embodiment, scope The leading detection of mode of extension notifies that at least data division is use range extended coding scheme and generates to receiving device signal 's.

In embodiment, the leading leading Part II for including the second OFDM symbol including generation is generated, it is used for i) According to the short training field and ii of the first communication protocol) at least one copy of short training field, and generate the 3rd OFDM symbols Number, it is used for i) according to the long training field and ii of the first communication protocol) at least one copy of long training field.In another reality In applying example, there is the OFDM symbol, the second OFDM symbol and the 3rd OFDM symbol for data division identical tone to plan, should Identical tone is planned different from the tone planning for leading Part I.

In another embodiment, block 2704 includes being generated according to the second communication protocol (for example, legacy communication protocols) and is directed to First signal field of PHY data unit and secondary signal field is generated as the copy of the first signal field to indicate data word At least some OFDM symbol of section is generated according to scope mode of extension.In another embodiment, the first signal field and Binary signal field indicates that the duration of PHY data unit is predetermined lasting time and secondary signal field is as supplementing instruction Section of practising handwriting can be used by the receiver apparatus for meeting the first communication protocol.In another embodiment, the first signal field and Binary signal field is to combine decodable by the receiver apparatus for meeting the first communication protocol, to increase the first signal field and The decoding reliability of binary signal field.

In embodiment, leading Part I includes i) leaving short training field, and it meets the second communication protocol, ii) Non-legacy long training field, and iii) signal field is left, it meets the second communication protocol, and leading Part II is not wrapped Include any training field.In this embodiment, planned for leaving Short Training using the tone of leaving for meeting the second communication protocol Field generates more than first constellation symbol, and more than second star is generated for non-legacy long training field using the planning of non-legacy tone Seat symbol；And include planning many constellation symbols of generated the 3rd using non-legacy tone for the OFDM symbol of data field Number.

In embodiment, the leading Part I that is directed to using normal protection interval and generate OFDM symbol using as symbol Close that leaving for the second communication protocol is leading, and OFDM symbol is generated for leading Part II using long protection interval. In another embodiment, the non-legacy signal field and non-legacy for leading Part II is generated using normal protection interval The OFDM symbol of short training field, and generated for leading second for non-legacy long training field using long protection interval Partial OFDM symbol.In another embodiment, signal letters is left for leading Part I using normal protection interval Duan Shengcheng OFDM symbols, and generate OFDM symbols for the non-legacy signal field of leading Part II using long protection interval Number.In embodiment, leading Part II be it is decodable by the receiver apparatus for meeting the first communication protocol, and second Leading long protection interval notifies that PHY data unit meets scope extension to the receiver apparatus signal for meeting the first communication protocol Pattern.In another embodiment, OFDM symbol is generated for leading Part II using long protection interval, it is used for i) non-something lost Stay signal field and ii) for non-legacy signal field the first OFDM symbol copy.In embodiment, for including following Each field in multiple fields of every leading Part II generates OFDM symbol：I) double protection interval, ii) pin The first OFDM symbol to field, and iii) as the first OFDM symbol copy the second OFDM symbol for field.

At block 2706, generation is included in the data division that is leading and being generated at block 2702 generated at block 2704 Data cell.In embodiment, PHY data unit is generated with comprising double protection interval according to the second communication protocol, it is double Protection interval is followed by the Part I of signal field and the Part II of signal field, the first signal field and secondary signal word Unprotected interval between section.

In certain embodiments, with compared with data field through-put power lifted come at least transmit leading Part I with Increase the decoding ranges of leading Part I.

In another embodiment, the OFDM symbols for data field are generated using the first tone spacing and long protection interval Number, and generate the OFDM for leading Part I using following item：I) the second tone spacing, itself and the first tone spacing Difference, and ii) GPF (General Protection False interval.In another embodiment, the second tone spacing of leading Part I is i) to meet Two communication protocols leave tone spacing, and ii) integral multiple of the first tone spacing of data field, and GPF (General Protection False is spaced Be meet the second communication protocol leave protection interval.In another embodiment, the OFDM for leading Part II is generated Symbol, including i) use leaves tone spacing and leaves at least the first OFDM symbol and the ii of protection interval) use the first tone At least second OFDM symbol of spacing and long protection interval.In another embodiment, generated for number using the first tone spacing According to the OFDM symbol of field, with the second of the multiple constellation symbols in the first portions of bandwidth including channel width and channel width The copy of the multiple constellation symbols in portions of bandwidth, and the first portions of bandwidth and the second portions of bandwidth have same band. In another embodiment, the OFDM symbol for being directed to data field is generated including the copy for generating multiple constellation symbols with comprising predetermined phase Position skew.

In embodiment, generation includes using the first tone spacing, long protection interval for the OFDM symbol of data field The OFDM symbol for data field is generated with the long symbol duration.In another embodiment, generate and be directed to leading first Partial OFDM symbol includes using the second tone spacing, GPF (General Protection False interval and proper symbol duration to generate for leading Part I OFDM symbol.In another embodiment, the second tone spacing of leading Part I is i) to leave tone Spacing and ii) data field the first tone spacing Integer n times, GPF (General Protection False interval is to leave protection interval, and long symbol Number duration is the Integer n times of ordinary symbol duration.

In another embodiment, the OFDM symbols of the data field for PHY data unit are generated according to scope mode of extension Number include：Data field is directed to using the non-legacy tone spacing and non-legacy tone plane-generating for not meeting the second communication protocol OFDM symbol；And generate it is leading including using the second tone spacing different from non-legacy tone spacing and with non-legacy sound Adjust and plan the different OFDM symbols that tone plane-generating is directed to leading Part I of leaving.In another embodiment, non-something lost Tone planning is stayed to include at least one protection of corresponding data tones of the close direct current tone for replacing leaving tone planning Tone.In embodiment, the planning of non-legacy tone includes replacing at least one of the corresponding protection tone for leaving tone planning Data tones so that non-legacy tone plans and leave that tone planning has equal number of data tones.In another embodiment In, the planning of non-legacy tone includes planning less data tones and using non-legacy tone spacing and non-something lost than leaving tone Stay tone plane-generating to include the number of the data tones based on the planning of non-legacy tone for the OFDM symbol of data field, make The information bit of OFDM symbol is directed to error correcting code coding.In embodiment, error correcting code is Binary Convolutional Code.In another enforcement In example, error correcting code is low density parity check code.

Figure 28 is the flow chart for generating the exemplary method 2800 of data cell according to embodiment.With reference to Fig. 1, in reality In applying example, by the implementation method 2800 of network interface 16.For example, in one suchembodiment, PHY processing units 20 are matched somebody with somebody It is set to implementation method 2800.According to another embodiment, MAC processes 18 at least a portion for being also arranged to implementation method 2800. With continued reference to Fig. 1, in another embodiment, by network interface 27 (for example, PHY processing units 29 and/or MAC processing units 28) implementation method 2800.In other embodiments, by other suitable network interface implementation methods 2800.

In embodiment, at block 2802, for PHY data unit to be comprised in leading the first field generate More than first OFDM (OFDM) symbol.In certain embodiments, each OFDM symbol in more than first OFDM symbol Number with least through predetermined sequence is multiplied the first obtained communication protocol with the second long training sequence of the second communication protocol The first long training sequence it is corresponding.In embodiment, at block 2804, coding is directed to more than first of the second leading field Information bit is generating more than first coded-bit.

In embodiment, at block 2806, more than first coded-bit is mapped to more than first constellation symbol.In embodiment In, at block 2808, more than first modified constellation symbols being generated, it includes for more than first constellation symbol being multiplied by pre- sequencing Row.In embodiment, at block 2810, generation includes more than second orthogonal frequency division multiplexing of more than first modified constellation symbol With (OFDM) symbol.In embodiment, at block 2812, leading more than first OFDM symbol including for the first field is generated It is leading with more than second OFDM symbol for the second field.At block 2814, PHY data unit is generated with including at least front Lead.

In certain embodiments, more than first information bit include indicating one of the duration of PHY data unit or The first set of multiple information bits, it is leading be formatted such that it is leading by meeting second communication protocol but do not meet institute State the receiver apparatus decodable code of the first communication protocol to determine the duration of PHY data unit based on leading.Implementing In example, i-th value of the first long training sequence is multiplied by predetermined sequence corresponding to i-th value corresponding with the second long training sequence I-th value, wherein i be index.

In embodiment, the length of the first long training sequence is accorded with more than or equal to the OFDM by the second communication protocol defined The number of the data tones in number and the number sum of pilot tones.In certain embodiments, more than first are generated individual modified Constellation symbol includes predetermined sequence is multiplied by the multiple pilot tones constellation symbols for the second communication protocol.In some embodiments In, the value of the predetermined sequence corresponding with multiple pilot tones constellation symbols has 1 value.In embodiment, predetermined sequence Value has+1 or -1 value.

In certain embodiments, generating more than first OFDM symbol includes generating more than first OFDM symbol so that be directed to Signal is notified i) the first communication protocols by the auto-correlation output of the first field generated by the receiver for meeting the first communication protocol The first mode or ii of view) the first communication protocol second mode, to enable the first mode or the second mould of receiver apparatus The automatic detection of formula.In embodiment, the first field includes the first long training sequence.In another embodiment, the first field bag Include the second long training sequence.

In embodiment, method 2800 also includes：More than the second information ratio to the data field for PHY data unit Spy is encoded to generate more than second coded-bit；By the bit map of more than second codings to more than second constellation symbol； Generating more than second modified constellation symbol includes for predetermined sequence being multiplied by more than second constellation symbol；Generation is included more than second 3rd many OFDM (OFDM) symbols of individual modified constellation symbol；And generation includes the 3rd many OFDM symbols Number data field, include generating PHY data unit with including at least leading and data field wherein generating PHY data unit.

Figure 29 is to meet HEW communication protocols compared with the leading part 2904 for meeting legacy protocol, according to embodiment The diagram of the leading part 2900 of example PHY of view.In embodiment, the Network Interface Unit 16 of AP 14 is configured to Jing Generated to client stations 25-1 and sent including PHY's leading 2900 from being modulated according to the orthogonal frequency domain of embodiment multiplexing (OFDM) Data cell.In embodiment, it is true that the Network Interface Unit 27 of client stations 25-1 is configured with technology discussed below Surely the first communication protocol is met comprising leading 2900 data cell.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to generate to AP and send include The data cell of PHY leading 2900.In embodiment, the Network Interface Unit 16 of AP 14 is configured with discussed below Technology to determine and meet the first communication protocol comprising leading 2900 data cell.

According to embodiment, meet the first communication protocol comprising the leading data cells 2900 of PHY and occupy 20MHz bands It is wide.In various other embodiments, meet the first communication protocol and comprising the leading data cell similar with leading 2900 Can take up other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other are suitable Bandwidth.Leading 2900 are suitable to " mixed mode " situation, i.e. when WLAN 10 includes meeting legacy communication protocols rather than the first communication During client stations (for example, the leaving client stations 25-4) of agreement.In certain embodiments, leading 2900 also utilize in other situations In.

Leading part 2900 includes L-LTF 204/304/504.In embodiment, L-LTF 204/304/504 includes double Protection interval 2908, a L-LTF OFDM symbols 2912 and the 2nd L-LTF OFDM symbols 2916.According to embodiment, front pilot 2900 are divided also to include L-SIG 206/306/506, it includes protection interval 2920 and L-SIG OFDM symbols 2924.According to enforcement Example, L-LTF 204/304/504 and L-SIG 206/306/506 is and leaves leading 2904 and (for example, meet IEEE 802.11a Standard, IEEE 802.11g standards, IEEE 802.11n standards and/or IEEE 802.11ac standards it is leading) corresponding A part for the Part I of leading the 2900 of part matching.Legacy devices can decode that L-SIG 206/306/506 and It is determined that the length of the PHY data unit comprising PHY leading 2900.For example, in embodiment, L-SIG 206/306/506 includes It is set to the length field of the value of the length for indicating the PHY data unit comprising PHY leading 2900.

Leading 2900 include secondary L-SIG fields 2928.In embodiment, L-SIG fields 2928 are L-SIG fields 206/ 306/506 duplication.In embodiment, it is configured to be configured to before detection according to the communication equipment of the first communication protocol operations Lead the repetition of the L-SIG fields 206/306/506 in 2900, and based on L-SIG fields 206/306/506 detected connect Receive, determine that leading 2900 meet the first communication protocol.In embodiment, once detect L-SIG fields 206/306/506, 2928 repetition, then in embodiment, the duplication in the L-SIG fields that receiving device will repeat is used as additional training information to change Enter channel estimation.In certain embodiments, receiving device decodes first L-SIG 206/306/506, and and then uses L-SIG The repetition of the value detection L-SIG fields 206/306/506,2928 of the Length subfield in 206/306/506.In another embodiment In, receiving device detects first the repetition of L-SIG fields 206/306/506,2928, and and then multiple L- for being detected of combination SIG fields 206/306/506,2928 are improving the decoding reliability of L-SIG fields 206/306/506,2928, and/or use Redundancy in multiple L-SIG fields 206/306/506,2928 is improving channel estimation.

In embodiment, leading 2900 also include HEW-SIG1 fields 2932, and it includes DGI 2936 and HEW-SIG1 words Section OFDM symbol 2940.Leading 2900 also include secondary HEW-SIG1 fields 2944.In embodiment, HEW-SIG1 fields 2944 It is the duplication of HEW-SIG1 fields 2932.In embodiment, meet the HEW- that the receiving device of the first communication protocol will repeat In SIG1 fields 2932,2944 duplication as additional training information to improve embodiment in channel estimation.In another enforcement In example, meet receiving device multiple HEW-SIG1 fields 2932,2944 for being detected of combination of the first communication protocol to improve The decoding reliability of HEW-SIG1 fields 2932,2944, and/or using the redundancy in multiple HEW-SIG1 fields 2932,2944 Information is improving channel estimation.

In embodiment, leading part 2900 is formatted so that according to the receiving device energy of the first communication protocol configuration Enough determinations include that leading 2900 data cell meets the first communication protocol.For example, in embodiment, LTF fields 204/304/ The 504 modified LTF fields 2304 for corresponding to Figure 23, and in embodiment, first leaves signal field 206/306/506 Modified corresponding to Figure 23 leaves signal field 2306.In this embodiment, receive comprising leading 2900 data cell Receiving device the first mutual of LTF204/304/504 can be performed by using the long training sequence of legacy communication protocols The modified long training sequence of pass and the first communication protocol used in embodiment as described by above for Figure 23 comes Second cross-correlation of execution LTF fields 204/304/504 carrys out detection data unit and meets the first communication protocol.

In embodiment, the leading part 3201 of data cell 3200 is also formatted in addition to enable Legacy communications equipment Enough determine that data cell 3200 does not meet legacy communication protocols.For example, in embodiment, a L-SIG fields 3202, the 2nd L- SIG fields 3204 and HEW-SIG1 fields 3208 are each modulated so that receiving device will be detected with Legacy Data cell BPSK modulation in OFDM symbol at the corresponding position of formula 3220.For example, in embodiment, once detect corresponding to BPSK modulation in the OFDM symbol of one L-SIG fields 3202, the 2nd L-SIG fields 3204 and HEW-SIG1 fields 3206, connects Receiving unit will stop processing data unit 3200, and will suppress to visit for the duration determined based on L-SIG fields 3204 Ask medium.

Figure 30 be compared with the leading part 2904 for meeting legacy protocol, according to another embodiment meet first lead to Believe the diagram of the leading part 3000 of example PHY of agreement.Leading 3000 is similar with leading the 2900 of Figure 29, and identical volume Number element do not discussed in detail.In embodiment, the Network Interface Unit 16 of AP 14 is configured It is via modulating the data cell that generates to client stations 25-1 and send including PHY leading 3000 according to the OFDM of embodiment. In embodiment, the Network Interface Unit 27 of client stations 25-1 is configured with technology discussed below and determines comprising leading 3000 data cell meets the first communication protocol.

In embodiment, the Network Interface Unit 27 of client stations 25-1 be additionally configured to generate to AP and send including The data cell of PHY leading 3000.In embodiment, the Network Interface Unit 16 of AP 14 is configured with discussed below Technology to determine and meet the first communication protocol comprising leading 3000 data cell.

According to embodiment, including the data cell of PHY leading 3000 meets the first communication protocol and occupies 20MHz bands It is wide.In various other embodiments, meet the first communication protocol and including the leading data cell similar with leading 3000 Can take up other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other are suitable Bandwidth.Leading 3000 are suitable to " mixed mode " situation, i.e. when WLAN 10 includes meeting legacy communication protocols rather than the first communication During client stations (for example, the leaving client stations 25-4) of agreement.In certain embodiments, leading 3000 also utilize in other situations In.

Secondary L-SIG 2928 is omitted unlike leading 2900, leading 3000.Additionally, unlike leading 2900, HEW-SIG1 3004 include GI 3008 rather than DGI.HEW-SIG1 3004 also includes HEW-SIG1 OFDM symbols 3012.In embodiment, HEW-SIG1 3016 is the duplication of HEW-SIG1 3004.Leading 3000 also include HEW-SIG2 3020, and it includes DGI 3024 With HEW-SIG2OFDM symbols 3028.

According to embodiment, L-LTF 204/304/504 and L-SIG 206/306/506 is and leaves leading 2904 (for example, Meet IEEE 802.11a standards, IEEE 802.11g standards, IEEE 802.11n standards and/or IEEE 802.11ac standards It is leading) corresponding Part I matching leading 3000 Part I a part.Legacy devices can decode that L-SIG 206/306/506 and determine comprising PHY leading 3000 PHY data unit length.For example, in embodiment, L-SIG The length field of 206/306/506 value for including the length for being set to the PHY data unit for indicating to include PHY leading 3000.

In embodiment, it is configured to be configured in detection leading 3000 according to the communication equipment of HEW agreements operation The repetition of HEW-SIG1 fields 3004,3016, and the repetition for being detected based on HEW-SIG1 fields 3004,3016, it is determined that Leading 3000 meet HEW communication protocols.

Repetition in embodiment, in the HEW-SIG1 fields 3004,3016 that the receiving device for meeting HEW agreements will be repeatedly As additional training information to improve embodiment in channel estimation.In another embodiment, the receiving device of HEW agreements is met Combination detected multiple 3004,3016 improving the decoding reliability of HEW-SIG1 fields 3004,3016, and/or using many Redundancy in individual HEW-SIG1 fields 3004,3016 is improving channel estimation.

Figure 31 be compared with the leading part 2904 for meeting legacy protocol, according to another embodiment meet first lead to Believe the diagram of the leading part 3100 of example PHY of agreement.Leading 3100 with leading the 2900 of Figure 29 and Figure 30 it is leading 3000 are similar to, and the element of identical numbering is not discussed in detail.

In embodiment, the Network Interface Unit 16 of AP 14 is configured to be modulated to visitor via the OFDM according to embodiment Family station 25-1 generates and sends the data cell including PHY leading 3100.In embodiment, the network interface of client stations 25-1 Equipment 27 is configured with technology determination discussed below includes that leading 3100 data cell meets the first communication protocol.

In embodiment, the Network Interface Unit 27 of client stations 25-1 be additionally configured to generate to AP and send including The data cell of PHY leading 3100.In embodiment, the Network Interface Unit 16 of AP 14 is configured with discussed below Technology determine include that leading 3100 data cell meets the first communication protocol.

According to embodiment, including the data cell of PHY leading 3100 meets the first communication protocol and occupies 20MHz bands It is wide.In various other embodiments, meet the first communication protocol and including the leading data cell similar with leading 3100 Can take up other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other are suitable Bandwidth.Leading 3100 are suitable to " mixed mode " situation, i.e. when WLAN 10 includes meeting legacy communication protocols rather than the first communication During client stations (for example, the leaving client stations 25-4) of agreement.In certain embodiments, leading 3100 also utilize in other situations In.

Unlike leading 2900, HEW-SIG1 3004 includes GI 3008 rather than DGI.HEW-SIG1 3004 also includes HEW-SIG1 OFDM symbols 3012.In embodiment, HEW-SIG1 3016 is the duplication of HEW-SIG1 3004.Leading 3100 Also include HEW-SIG2 3020, it includes DGI 3024 and HEW-SIG2OFDM symbols 3028.

Unlike leading 3000, leading 3100 including secondary L-SIG fields 2928.In embodiment, L-SIG fields 2928 are The duplication of L-SIG fields 206/306/506.

In embodiment, it is configured to be configured in detection leading 2900 according to the communication equipment of HEW agreements operation The repetition of L-SIG fields 206/306/506, and the repetition for being detected based on L-SIG fields 206/306/506, it is determined that before Lead 2900 and meet HEW communication protocols.In embodiment, once L-SIG fields 206/306/506,2928 are detected, in embodiment In, the duplication in the L-SIG fields that receiving device will repeat is used as additional training information to improve channel estimation.In some enforcements In example, receiving device decodes first L-SIG 206/306/506, and and then using the length in L-SIG 206/306/506 The repetition of the value detection L-SIG fields 206/306/506 of son field.In another embodiment, receiving device detects first L-SIG The repetition of field 206/306/506,2928, and and then multiple L-SIG fields 206/306/506,2928 for being detected of combination To improve the decoding reliability of L-SIG fields 206/306/506,2928, and/or using multiple L-SIG fields 206/306/ 506th, the redundancy in 2928 is improving channel estimation.

Figure 32 is that the Network Interface Unit 16 of the AP 14 according to embodiment is configured to be modulated to client stations via OFDM The diagram of a part for leading the 3200 of the OFDM data unit that 25-1 is generated and sent.In embodiment, client stations 25-1 Network Interface Unit 27 be configured with technology discussed below and determine that the data cell for including leading 3200 meets the One communication protocol.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to be sent to AP includes leading 3200 Data cell.In embodiment, the Network Interface Unit 16 of AP 14 is configured with technology determination discussed below to be included Leading 3200 data cell meets the first communication protocol.

Meet the first communication protocol comprising leading 3200 data cell and occupy 20MHz bandwidth.In various other realities In applying example, other are can take up with the leading data cell that meet first communication protocol similar with leading 3200 suitable Bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.Data cell 700 is fitted In " mixed mode " situation, i.e. when WLAN 10 includes meeting the client stations (example of legacy communication protocols rather than the first communication protocol Such as, client stations 25-4 is left) when.In certain embodiments, comprising leading 3200 data cell also using in other cases.

Leading 3200 include the leading part 3210 with the first long protection interval 3202, with Part I 3204-1 and The long training field 3204 of Part II 3204-2, the second long protection interval 3206, L-SIG fields 3206-1, the 2nd L- SIG fields 3206-2, the 3rd long protection interval 3202, a HEW signal fields HEW-SIG1 3208, the 4th long protection interval 3202 and the 2nd HEW signal fields HEW-SIG2 3210.In embodiment, L-SIG fields 3602-1 correspond to data sheet The L-SIG fields 706 of unit 700, and the 2nd L-SIG fields 3602-2 are the duplications of L-SIG fields 3062-1.Implementing In example, each long protection interval 3202 is long double guarantors as the twice at the GPF (General Protection False interval defined by legacy communication protocols Shield interval.For example, in embodiment, the normal protection interval defined by legacy communication protocols is 0.8 μ s, and double protection intervals are 1.6μs.In another embodiment, each in long protection interval 3202 has more than the routine defined by legacy communication protocols Another suitable value of protection interval.For example, in various embodiments, the GPF (General Protection False interval for being defined by legacy communication protocols is 0.8 μ s, long protection interval is 1.2 μ s, 2.4 μ s, 3.2 μ s or another suitable value more than 0.8 μ s.

With continued reference to Figure 32, it is illustrated that Legacy Data cell format 3220 is for reference.Meet the data sheet of form 3220 Unit includes double protection interval 3222, the long training fields 3224, first with Part I 3224-1 and Part II 3224-2 GPF (General Protection False interval 3225, L-SIG fields 3226, corresponding to signal field (for example, HT-SIG1 fields or VHT-SIG1 words Section) OFDM symbol 3228 or the data division depending on 3200 corresponding specific legacy protocols OFDM symbol, the 3rd normal Rule protection interval 3225 and the OFDM symbol 3230 corresponding to signal field (for example, HT-SIG fields or VHT-SIG2 fields) Or the OFDM symbol of the data division depending on the corresponding specific legacy protocol of form 3200.

In embodiment, the leading part 3201 of data cell 3200 is formatted so that being matched somebody with somebody according to the first communication protocol The receiving device put can determine that data cell 3200 corresponds to the first communication protocol.For example, in embodiment, L-LTF fields The 3204 modified LTF fields 2304 for corresponding to Figure 23, and in embodiment, first leaves signal field 3206 corresponds to The modified of Figure 23 leaves signal field 2306.In this embodiment, the receiving device of receiving data unit 3200 can lead to The first cross-correlation to perform long training field 3202 is crossed using the long training sequence of legacy communication protocols and in embodiment L-LTF fields 3202 are performed using the modified long training sequence of the first communication protocol as described by above for Figure 23 The second cross-correlation carry out detection data unit 3200 and meet the first communication protocol.Additionally or alternatively, in embodiment, connect Receive data cell 3200 receiving device can by detect leading part 3201 in the 2nd L-SIG fields 3205 presence come Detection data unit 3200 meets the first communication protocol.

In embodiment, leading 3200 leading part 3201 is also formatted in addition to enable legacy communication protocols true Surely include that leading 3200 data cell does not meet legacy communication protocols.For example, in embodiment, a L-SIG fields 3202, 2nd L-SIG fields 3204 and HEW-SIG1 fields 3208 each modulated so that receiving device will be detected with Legacy Data list BPSK modulation in OFDM symbol at the corresponding position of first form 3220.For example, in embodiment, once detect correspondence BPSK in the OFDM symbol of a L-SIG fields 3202, the 2nd L-SIG fields 3204 and HEW-SIG1 fields 3206 is adjusted System, then receiving device will stop processing data unit 3200, and will be directed to the duration determined based on L-SIG fields 3204 Suppress to access medium.As illustrated in Figure 32, in embodiment, due to the long protection interval before L-SIG fields 3210, Thus the L-SIG fields 3204 in time domain do not have and corresponding OFDM symbol L-SIG 3224 pairs left in leading 3220 Together.On the other hand, the 2nd L-SIG fields 3212 are alignd with the corresponding OFDM symbol 3228 left in leading 3220.Schemed It is similar with a L-SIG fields 3208 in the embodiment shown, HEW-SIG1 fields in the time domain with leave it is leading in it is corresponding OFDM symbol 3230 is non-alignment.

In embodiment, pre-rotation is carried out to the constellation point of L-SIG fields 3206-1 and HEW-SIG1 fields 3208, So that constellation point is counted as the skew used by the Legacy communications equipment of the corresponding OFDM symbol with legacy format 3220 FFT windows in BPSK.In embodiment, the constellation point quilt of L-SIG fields 3206-1 and HEW-SIG1 fields 3208 Rotation is with amount determined by the length of the long protection interval caused by the duration of long protection interval.For example, it is long wherein to protect In the long embodiment as the twice at the GPF (General Protection False interval defined by legacy communication protocols in shield interval, a L-SIG fields The constellation point of each in 3206-1 and HEW-SIG1 fields 3208 is rotated by 90 degrees, as above for Figure 14 B- Figure 14 C institutes Description.Therefore, in this embodiment, using reverse QBPSK (R-QBPSK) modulation to L-SIG fields 3206-1 and HEW-SIG1 fields 3208 are each modulated.

In embodiment, the 2nd L-SIG fields 3206-2 and the corresponding OFDM symbol 3228 pairs in legacy format 3220 Together, and correspondingly, the 2nd L-SIG fields 3206-2 are modulated using BPSK modulation.In this embodiment, the 2nd L- The Cyclic Prefix of SIG fields 3206-2 does not match with the decline of L-SIG fields 3206-1 in embodiment.

Figure 33 is that the Network Interface Unit 16 of the AP 14 according to embodiment is configured to be modulated to client stations via OFDM The diagram of a part for leading the 3300 of the OFDM data unit that 25-1 sends.In embodiment, the network of client stations 25-1 connects Jaws equipment 27 is configured with technology determination discussed below includes that leading 3300 data cell meets the first communication protocols View.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to be sent comprising leading 3300 to AP Data cell.In embodiment, the Network Interface Unit 16 of AP 14 is configured with technology determination discussed below and includes Leading 3300 data cell meets the first communication protocol.

Meet the first communication protocol comprising leading 3300 data cell and occupy 20MHz bandwidth.In various other realities In applying example, meet the first communication protocol and with the leading data cell similar with leading 3300 can take up other be adapted to Bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.

Except second long protection interval 3202-2 is spaced 3302 by GPF (General Protection False in leading 3300 leading part 3301 Replace and omit outside the 2nd L-SIG fields 3206-2 from data cell 3300, leading 3300 and Fig. 2 leading 3200 class Seemingly.Additionally, compared with leading 3200 single HEW-SIG1 fields 3208, leading part 3301 includes a HEW-SIG1 words Section 3208-1 and the 2nd HEW-SIG1 fields 3208-2.In embodiment, the 2nd HEW-SIG1 fields 3208-2 are a HEW- The duplication of SIG1 fields 3208-1.

In embodiment, HEW-SIG1 fields 3208-2 of L-SIG fields 3206 and the 2nd each with legacy format 3220 in Its corresponding OFDM symbol alignment.On the other hand, HEW-SIG1 fields 3208-1 are not right with its of legacy format 3220 The OFDM symbol alignment answered.In embodiment, the constellation point of HEW-SIG fields 3208-1 is carried out pre-rotation (for example, with 90 degree) receiving device is caused by the BPSK modulation in the FFT windows for detecting corresponding to the skew of OFDM symbol 3228.Implementing In example, use BPSK modulation to be modulated the 2nd HEW-SIG1 fields 3208-2 and receiving device is detected leave lattice The BPSK modulation of the corresponding OFDM symbol 3330 in formula 3200.However, in this case, in embodiment, the 2nd HEW- The modulation of SIG1 fields 3208-2 (BPSK) is different with the modulation (for example, R-QBPSK) of HEW-SIG1 fields 3208-1.Cause This, the Cyclic Prefix of the 2nd HEW-SIG1 fields 3208-2 is simultaneously not exactly corresponding with HEW-SIG1 fields 3208-1 Decline matches.

Alternatively, in another embodiment, (for example, R- is modulated using with a HEW-SIG1 fields 3208-1 identical QBPSK) modulating the 2nd HEW-SIG1 fields 3208-2.In this embodiment, secondary signal field HEW-SIG1 field 3208- 2 Cyclic Prefix matches with the decline of the first signal field HEW-SIG1 fields 3208-1, and this causes non-legacy Can more accurately be detected comprising leading 3300 based on the repetition of the HEW-SIG1 fields detected in data cell 3300 Data cell corresponds to the first communication protocol.And, in this embodiment, legacy devices will detect corresponding OFDM symbol The modulation (for example, QPSK) of the skew in 3230, this may cause error detection data cell 3200 to meet IEEE-802-11ac The data cell of standard.However, legacy devices will be interpreted as VHT-SIG2 fields the 2nd HEW-SIG1 fields, and will make The crc check failure of VHT-SIG2 fields.In embodiment, according to IEEE 802.11ac standards, then legacy devices will abandon To suppress to visit for the duration indicated in L-SIG fields 3206 with leading 3300 data cell and in embodiment Ask medium.It is No. 13/856,277 U.S. Patent application (acting on behalf of institute's reel number the MP4709th) of the submission of on April 4th, 2013 In describe for guarantee legacy devices based on decoding the 2nd HEW-SIG1 fields 3208-2 detect crc error various methods, It is incorporated by reference into this with its entire content.

Figure 34 is that the Network Interface Unit 16 of the AP 14 according to embodiment is configured to be modulated to client stations via OFDM The diagram of a part for leading the 3400 of the OFDM data unit that 25-1 sends.In embodiment, the network of client stations 25-1 connects Jaws equipment 27 is configured with technology determination discussed below includes that leading 3400 data cell meets the first communication protocols View.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to be sent to AP includes leading 3400 Data cell.In embodiment, the Network Interface Unit 16 of AP 14 is configured with technology determination discussed below to be included Leading 3400 data cell meets the first communication protocol.

Meet the first communication protocol including leading 3400 data cell and occupy 20MHz bandwidth.In various other realities In applying example, meet the first communication protocol and with the leading data cell similar with leading 3400 can take up other be adapted to Bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.

In embodiment, except leading 3400 leading part 3401 is included between the OFDM symbol of leading part 3401 Long protection interval and including L-SIG fields 3206 duplication outside, leading 3400 is similar with leading the 3200 of Figure 32.This Outward, in the illustrated embodiment, unlike in leading 3200, the pre-rotation of the constellation point in leading 3400 OFDM symbol is not Align with the corresponding OFDM symbol in legacy format 3220.

Figure 35 is that the Network Interface Unit 16 of the AP 14 according to embodiment is configured to be multiplexed (OFDM) via orthogonal frequency domain Modulate the diagram of a leading part 3500 for the OFDM data unit sent to client stations 25-1.In embodiment, client stations The Network Interface Unit 27 of 25-1 is configured with technology discussed below and determines the data cell symbol for including leading 3500 Close the first communication protocol.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to be sent to AP includes leading 3500 Data cell.In embodiment, the Network Interface Unit 16 of AP 14 is configured with technology determination discussed below to be included Leading 3500 data cell meets the first communication protocol.

Meet the first communication protocol including leading 3500 data cell and occupy 20MHz bandwidth.In various other realities In applying example, meet the first communication protocol and with the leading data cell similar with leading 3500 can take up other be adapted to Bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.Except leading Outside second long protection interval 3302-2 is replaced using GPF (General Protection False interval 3502 in 3500, leading 3500 is leading with Figure 34 3400 is identical.In this case, in embodiment, L-SIG fields 3206 and its corresponding OFDM in legacy format 3220 Symbol (L-SIG fields 3226) aligns.

Figure 36 be compared with the leading part 2904 for meeting legacy protocol, according to another embodiment meet first lead to Believe the diagram of the leading part 3600 of example PHY of agreement.Leading 3600 is similar with leading the 2900 of Figure 29, and identical volume Number element do not discussed in detail.

In embodiment, the Network Interface Unit 16 of AP 14 is configured to be modulated to visitor via the OFDM according to embodiment Family station 25-1 generates and sends the data cell including PHY leading 3600.In embodiment, the network interface of client stations 25-1 Equipment 27 is configured with technology determination discussed below includes that leading 3600 data cell meets the first communication protocol.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to generate to AP and send include The data cell of PHY leading 3600.In embodiment, the Network Interface Unit 16 of AP 14 is configured with discussed below Technology to determine and meet the first communication protocol comprising leading 3600 data cell.

According to embodiment, including the leading data cells of PHY meet the first communication protocol and occupy 20MHz bandwidth. In various other embodiments, meet the first communication protocol and can account for including the leading data cell similar with leading 3600 According to other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth. Leading 3600 are suitable to " mixed mode " situation, i.e. when WLAN 10 includes meeting legacy communication protocols rather than the first communication protocol During client stations (for example, leaving client stations 25-4).In certain embodiments, leading 3600 also using in other cases.

In embodiment, due to the long protection interval 2936 before HEW-SIG1 OFDM symbols 2940, thus in time domain HEW-SIG fields 3604 do not align with corresponding OFDM symbol (V) the HT-SIG1 fields 3608 left in leading 2904.

In embodiment, the constellation point of HEW-SIG1 OFDM symbols 2940 is rotated to holding by long protection interval 2936 Measure determined by the length of the long protection interval 2936 that the continuous time causes.For example, wherein long protection interval with by Legacy communications In the equally long embodiment of twice at the GPF (General Protection False interval of protocol definition, the constellation point quilt of HEW-SIG1 OFDM symbols 2940 It is rotated by 90 °, as described by above for Figure 14 B- Figure 14 C.Therefore, in embodiment, using reverse QBPSK (R- QBPSK) modulation is modulated to HEW-SIG1 fields 3604.

Figure 37 is that the Network Interface Unit 16 of the AP 14 according to embodiment is configured to be multiplexed (OFDM) via orthogonal frequency domain Modulate the diagram of a leading part 3700 for the OFDM data unit for generating to client stations 25-1 and sending.In embodiment In, the Network Interface Unit 27 of client stations 25-1 is configured with technology discussed below and determines the number for including leading 3700 Meet the first communication protocol according to unit.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to generate to AP and send including front Lead 3700 data cell.In embodiment, the Network Interface Unit 16 of AP 14 is configured with technology discussed below It is determined that meeting the first communication protocol including leading 3700 data cell.

Meet the first communication protocol including leading 3700 data cell and occupy 20MHz bandwidth.In various other realities In applying example, meet the first communication protocol and including the leading data cell similar with leading 3700 can take up other be adapted to Bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.

Except leading 3700 the second (duplication) HEW-SIG1 fields 3208-2 of omission and including automatic detection OFDM symbol Outside 3706, leading 3700 is similar with leading the 3300 of Figure 33.In embodiment, receiving device can be based on and detect data sheet Automatic detection OFDM symbol 3706 in unit 3700 meets the first communication protocols to detect including leading 3700 data cell View.In the illustrated embodiment, automatic detection symbol 3706 immediately follows follows L-SIG fields 3206.In embodiment, automatically Detection symbols 3706 are alignd and at least with legacy format 3220 with its corresponding OFDM symbol in Legacy Data unit Corresponding OFDM symbol tone non-zero tone using BPSK modulation be modulated.In embodiment, long protection interval The 3710 HEW-SIG1 fields 3208 with leading 3700 are used together.In embodiment, leading 3700 HEW-SIG1 fields 3208 do not align with the corresponding OFDM symbol in legacy format 3220.Star in embodiment, to HEW-SIG1 fields 3208 Seat point carries out pre-rotation (for example, with 90 degree) and causes to leave receiving device to accord with the corresponding OFDM in using legacy format 3220 Number FFT windows detectings BPSK modulation.

Figure 38 A- Figure 38 D are the automatic detection OFDM symbols of the data in graph form unit 3700 according to several example embodiments 3706 diagram.Figure 38 A are tuning firstly to, in embodiment, automatic detection OFDM symbol 3706 includes being determined by legacy communication protocols Five repetitions of the L-LTF sequences of justice.In this embodiment, non-legacy receiving device can be used to be based on by reusing The L-STF fields that are included in the beginning of data cell 3700 and the Packet Detection Algorithms of the beginning of detection data unit 3700 Start, carry out detection data unit 3700 and meet the first communication protocol.Turning now to Figure 38 B, in embodiment, automatic detection OFDM Symbol 3706 includes being adapted to for longer compared with the L-STF sequences defined by legacy communication protocols (corresponding to more multi-OFDM tone) Predetermined sequence two repetitions.For example, in embodiment, predetermined sequence includes each the 20MHz frequency with data cell 3700 In band every an OFDM tone (for example, with the OFDM tones of the index in set [+/- 2 ,+/ 4, +/- 6 etc.]) correspondence Value.Turning now to Figure 38 C, in embodiment, automatic detection OFDM symbol 3706 includes the decline of L-SIG fields 3206 Five repetitions of (for example, last 0.8 μ s).Turning now to Figure 38 C, in embodiment, automatic detection OFDM symbol 3706 includes Two repetitions of the greater part (for example, 1.6 μ s) of L-SIG fields 3206, are followed by the greater part of L-SIG fields 3206 The suffix portion of the subdivision of (for example, 0.8 μ s).

In other embodiments, automatic detection OFDM symbol 3706 is included at receiving device can be used to automatically detect Meet any other suitable predetermined sequence of the first communication protocol comprising leading 3700 data cell.For example, in various realities In applying example, automatic detection OFDM symbol 3706 include predetermined Bark (Barker) code sequence, predetermined Gray code (Golay) sequence or Person any other suitable predetermined sequence.In embodiment, receiving device by detection automatic detection OFDM symbol 3706 with it is pre- The high correlation of sequencing row meets the first communication protocol detecting the data cell comprising leading 3700.

Figure 39 be compared with the leading part 2904 for meeting legacy protocol, according to another embodiment meet first lead to Believe the diagram of the leading part 3900 of example PHY of agreement.Leading 3900 is similar with leading the 2900 of Figure 29, and identical volume Number element do not discussed in detail for purposes of brevity.

In embodiment, the Network Interface Unit 16 of AP 14 is configured to be modulated to visitor via the OFDM according to embodiment Family station 25-1 generates and sends the data cell including PHY leading 3900.In embodiment, the network interface of client stations 25-1 Equipment 27 is configured with technology determination discussed below includes that leading 3900 data cell meets the first communication protocol.

In embodiment, the Network Interface Unit 27 of client stations 25-1 be additionally configured to generate to AP and send including The data cell of PHY leading 3900.In embodiment, the Network Interface Unit 16 of AP 14 is configured with discussed below Technology determine include that leading 3900 data cell meets the first communication protocol.

According to embodiment, including the leading data cells of PHY meet the first communication protocol and occupy 20MHz bandwidth. In various other embodiments, meet the first communication protocol and can account for including the leading data cell similar with leading 3900 According to other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth. Leading 3900 are suitable to " mixed mode " situation, i.e. when WLAN 10 includes meeting legacy communication protocols rather than the first communication protocol During client stations (for example, leaving client stations 25-4).In certain embodiments, leading 3900 also using in other cases.

According to embodiment, L-SIG 206/36/506, L-SIG 2928 and HEW-SIG1 2932 are adjusted using BPSK System, but HEW-SIG1 2944 is modulated using the BPSK (for example, Q-BPSK) for rotating.

Figure 40 A are according to the leading part 4000 of another example PHY for meeting the first communication protocol of another embodiment Diagram.

In embodiment, the Network Interface Unit 16 of AP 14 is configured to be modulated to visitor via the OFDM according to embodiment Family station 25-1 generates and sends the data cell including PHY leading 4000.In embodiment, the network interface of client stations 25-1 Equipment 27 is configured with technology determination discussed below includes that leading 4000 data cell meets the first communication protocol.

In embodiment, the Network Interface Unit 27 of client stations 25-1 be additionally configured to generate to AP and send including The data cell of PHY leading 4000.In embodiment, the Network Interface Unit 16 of AP 14 is configured with discussed below Technology determine include that leading 4000 data cell meets the first communication protocol.

According to embodiment, including the leading data cells of PHY meet the first communication protocol and occupy 20MHz bandwidth. In various other embodiments, meet the first communication protocol and can account for including the leading data cell similar with leading 4000 According to other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth. Leading 4000 are suitable to " mixed mode " situation, i.e. when WLAN 10 includes meeting legacy communication protocols rather than the first communication protocol During client stations (for example, leaving client stations 25-4).In certain embodiments, leading 4000 also using in other cases.

Leading part 4000 includes legacy part 4004, and it has a L-LTF OFDM symbols 4008, the 2nd L-LTF OFDM symbol 4012 and L-SIG OFDM symbols 4016.In embodiment, double guarantors were included before L-LTF OFDM symbols 4008 Shield interval (not shown), and include protection interval between L-LTF OFDM symbols 4012 and L-SIG OFDM symbols 4016. According to embodiment, legacy devices can decode that L-SIG 4016 and determine the length of the PHY data unit for including PHY leading 4000 Degree.For example, in embodiment, L-SIG 4016 includes being set to the length of the PHY data unit for indicating to include PHY leading 4000 Value length field.

In embodiment, L-LTF fields 4012 correspond to the modified LTF fields 2304 of Figure 23, and in embodiment In, L-SIG 4016 leaves signal field 2306 corresponding to the modified of Figure 23.In this embodiment, the first communication protocols are met The receiving device of view can perform first cross-correlation of L-LTF 4008 by using the long training sequence of legacy communication protocols And the modified long training sequence of the first communication protocol used in embodiment as described by above for Figure 23 and hold Second cross-correlation of row L-LTF fields 4012 meets the first communication protocol detecting the data cell including leading 4000.

PHY leading 4000 include one or more HEW-STF OFDM symbols 4020, HEW-LTF1 OFDM symbols 4024, HEW-SIGA OFDM symbols 4028, one or more HEW-LTF OFDM symbols 4032 and HEW-SIGB OFDM symbols 4036.In embodiment, DGI is included between L-SIG 4016 and HEW-STF 4020a.In embodiment, in HEW-STF Between OFDM symbol 4020b and HEW-LTF1 OFDM symbols 4024, in HEW-LTF1 OFDM symbols 4024 and HEW-SIGA Between OFDM symbol 4028, between HEW-SIGA OFDM symbols 4028 and one or more HEW-LTF OFDM symbols 4032 And including corresponding DGI between one or more OFDM symbols 4032 and HEW-SIGB OFDM symbols 4036.

Figure 40 B are according to the leading part 4050 of another example PHY for meeting the first communication protocol of another embodiment Diagram.Leading part 4050 is similar with leading part 4000, and the element of identical numbering is not carried out for purposes of brevity Discuss in detail.

In embodiment, the Network Interface Unit 16 of AP 14 is configured to be modulated to visitor via the OFDM according to embodiment Family station 25-1 generates and sends the data cell including PHY leading 4050.In embodiment, the network interface of client stations 25-1 Equipment 27 is configured with technology determination discussed below includes that leading 4050 data cell meets the first communication protocol.

In embodiment, the Network Interface Unit 27 of client stations 25-1 be additionally configured to generate to AP and send including The data cell of PHY leading 4050.In embodiment, the Network Interface Unit 16 of AP 14 is configured with discussed below Technology determine include that leading 4050 data cell meets the first communication protocol.

According to embodiment, including the data cell of PHY leading 4050 meets the first communication protocol and occupies 20MHz bands It is wide.In various other embodiments, meet the first communication protocol and including the leading data cell similar with leading 4050 Can take up other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other are suitable Bandwidth.Leading 4050 are suitable to " mixed mode " situation, i.e. when WLAN 10 includes meeting legacy communication protocols rather than the first communication During client stations (for example, the leaving client stations 25-4) of agreement.In certain embodiments, leading 4050 also utilize in other situations In.

According to embodiment, legacy devices can decode that L-SIG 4016 and determination includes the PHY data of PHY leading 4050 The length of unit.For example, in embodiment, L-SIG 4016 includes being set to the PHY data sheets for indicating to include PHY leading 4050 The length field of the value of the length of unit.

Leading 4050 also include one or more secondary L-SIG 4054.In embodiment, one or more secondary L-SIG 4054 is the duplication of L-SIG 4016.

In embodiment, L-LTF fields 4012 correspond to the modified LTF fields 2304 of Figure 23, and in embodiment In, L-SIG 4016 leaves signal field 2306 corresponding to the modified of Figure 23.In this embodiment, the first communication protocols are met The receiving device of view can perform first cross-correlation of L-LTF 4008 by using the long training sequence of legacy communication protocols And the modified long training sequence of the first communication protocol used in embodiment as described by above for Figure 23 and hold Second cross-correlation of row L-LTF fields 4012 meets the first communication protocol detecting the data cell including leading 4050.

Additionally or alternatively, in embodiment, reception includes that the receiving device of leading 4050 data cell can The presence of one or more the secondary L-SIG fields 4054 in by detecting leading part 4050 meets the come detection data unit One communication protocol.

In embodiment, DGI is included between L-SIG 4054b and HEW-STF 4020a.In embodiment, in HEW- Between STF OFDM symbols 4020b and HEW-LTF1 OFDM symbols 4024, in HEW-LTF1 OFDM symbols 4024 and HEW- Between SIGA OFDM symbols 4028, in HEW-SIGA OFDM symbols 4028 and one or more HEW-LTF OFDM symbols 4032 Between and between one or more OFDM symbols 4032 and HEW-SIGB OFDM symbols 4036 include corresponding DGI.

In certain embodiments, such as technique described above can be used to detect the number for meeting the first communication protocol According to unit and detection data unit corresponding to which pattern (by the first communication protocol definition) in multiple patterns.Example Such as, Figure 41 is to meet the first communication protocols compared with the leading part 2904 for meeting legacy protocol, according to another embodiment The diagram of the leading part 4100 of example PHY of view.Additionally, PHY leading 4100 also corresponds to the scope of the first communication protocol Mode of extension.Figure 41 also includes meeting compared with the leading part 2904 for meeting legacy protocol, according to another embodiment The diagram of the leading part 4104 of example PHY of one communication protocol.Additionally, PHY leading 4104 also corresponds to the first communication protocol Normal mode.

In embodiment, the Network Interface Unit 16 of AP 14 is configured to be modulated to visitor via the OFDM according to embodiment Family station 25-1 generates and sends the data cell including PHY leading 4100 or PHY leading 4104.In embodiment, client The Network Interface Unit 27 of 25-1 of standing is configured with technology discussed below and determines to include leading 4100 or leading 4104 data cell meets the first communication protocol.In embodiment, the Network Interface Unit 27 of client stations 25-1 is configured to Being determined using technology discussed below includes that leading 4100 data cell meets scope mode of extension and including leading 4104 data cell meets normal mode.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to that bag is generated and sent to AP 14 Include the data cell of PHY leading 4100 or PHY leading 4104.In embodiment, the Network Interface Unit 16 of AP 14 is configured It is to determine that the data cell for including PHY leading 4100 or PHY leading 4104 meets first and leads to using technology discussed below Letter agreement.In embodiment, the Network Interface Unit 16 of AP 14 be configured with technology discussed below determine include it is front The data cell for leading 4100 meets scope mode of extension and the data cell including leading 4104 meets normal mode.

According to embodiment, including the data cell of PHY leading 4100 meets the first communication protocol and occupies 20MHz bands It is wide.In various other embodiments, meet the first communication protocol and including the leading data cell similar with leading 4100 Can take up other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other are suitable Bandwidth.According to embodiment, including the data cell of PHY leading 4101 meets the first communication protocol and occupies 20MHz bandwidth. In various other embodiments, meet the first communication protocol and can account for including the leading data cell similar with leading 4104 According to other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.

Leading 4100 is similar with leading the 2900 of Figure 29, and the element of identical numbering is not carried out for purposes of brevity in detail It is thin to discuss.Legacy devices can decode that L-SIG 206/306/506 and determination includes the PHY data unit of PHY leading 4100 Length.For example, in embodiment, L-SIG 206/306/506 includes being set to the PHY numbers for indicating to include PHY leading 4100 According to the length field of the value of the length of unit.

In embodiment, it is configured to be configured in detection leading 4100 according to the communication equipment of HEW agreements operation The repetition of L-SIG fields 206/306/506, and the repetition for being detected based on L-SIG fields 206/306/506, it is determined that before Lead 4100 and meet the first communication protocol.Additionally, being configured to be configured to base according to the communication equipment of the first communication protocol operations In the repetition for being detected of L-SIG fields 206/306/506, the leading 4100 scope expanded modes for meeting the first communication protocol are determined Formula.

Leading 4104 include DGI 4104, L-LTF 4108, L-LTF 4112, GI 4116 and L-SIG 4120.Implementing In example, L-LTF fields 4112 correspond to the modified LTF fields 2304 of Figure 23, and in embodiment, L-SIG 4120 couples Signal field 2306 should be left in the modified of Figure 23.In this embodiment, the receiving device energy of the first communication protocol is met It is enough first cross-correlation of L-LTF 4108 to be performed by using the long training sequence of legacy communication protocols and in embodiment L-LTF fields 4112 are performed using the modified long training sequence of the first communication protocol as described by above for Figure 23 The second cross-correlation meet the first communication protocol detecting the data cell including leading 4104.In a similar manner, is met The receiving device of one communication protocol can detect that the data cell including leading 4104 meets the normal mode of the first communication protocol.

In another embodiment, L-LTF fields 2916 correspond to the modified LTF fields 2304 of Figure 23, and in reality In applying example, L-SIG 2924 leaves signal field 2306 corresponding to the modified of Figure 23.In this embodiment, HEW associations are met The receiving device of view can perform first cross-correlation of L-LTF 2912 by using the long training sequence of legacy communication protocols And the modified long training sequence of the first communication protocol used in embodiment as described by above for Figure 23 and hold Second cross-correlation of row L-LTF fields 2916 meets HEW communication protocols detecting the data cell including leading 4100.

Figure 42 is to meet first compared with the leading part 2904 for meeting legacy protocol, according to another embodiment The diagram of the leading part 4200 of example PHY of communication protocol.Additionally, PHY leading 4200 also corresponds to the first communication protocol Scope mode of extension.Figure 42 is also included compared with the leading part 2904 for meeting legacy protocol, according to another embodiment The leading part 4204 of example PHY for meeting the first communication protocol diagram.Additionally, PHY leading 4204 also corresponds to first The normal mode of communication protocol.

In embodiment, the Network Interface Unit 16 of AP 14 is configured to be modulated to visitor via the OFDM according to embodiment Family station 25-1 generates and sends the data cell including PHY leading 4200 or PHY leading 4204.In embodiment, client The Network Interface Unit 27 of 25-1 of standing is configured with technology discussed below and determines to include leading 4200 or leading 4204 data cell meets the first communication protocol.In embodiment, the Network Interface Unit 27 of client stations 25-1 is configured to Being determined using technology discussed below includes that leading 4200 data cell meets scope mode of extension and including leading 4204 data cell meets normal mode.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to that bag is generated and sent to AP 14 Include the data cell of PHY leading 4200 or PHY leading 4204.In embodiment, the Network Interface Unit 16 of AP 14 is configured It is to determine that the data cell for including PHY leading 4200 or PHY leading 4204 meets first and leads to using technology discussed below Letter agreement.In embodiment, the Network Interface Unit 16 of AP 14 be configured with technology discussed below determine include it is front The data cell for leading 4200 meets scope mode of extension and the data cell including leading 4204 meets normal mode.

According to embodiment, including the data cell of PHY leading 4200 meets the first communication protocol and occupies 20MHz bands It is wide.In various other embodiments, meet the first communication protocol and including the leading data cell similar with leading 4200 Can take up other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other are suitable Bandwidth.According to embodiment, including the data cell of PHY leading 4101 meets the first communication protocol and occupies 20MHz bandwidth. In various other embodiments, meet the first communication protocol and can account for including the leading data cell similar with leading 4204 According to other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.

Leading 4200 is similar with leading the 3000 of Figure 30, and the element of identical numbering is not carried out for purposes of brevity in detail It is thin to discuss.Legacy devices can decode that L-SIG 206/306/506 and determination includes the PHY data unit of PHY leading 4200 Length.For example, in embodiment, L-SIG 206/306/506 includes being set to the PHY numbers for indicating to include PHY leading 4200 According to the length field of the value of the length of unit.

In embodiment, it is configured to be configured to detection leading 4200 according to the communication equipment of the first communication protocol operations In HEW-SIG1 fields 3004,3016 repetition, and the repetition for being detected based on HEW-SIG1 fields 3004,3016, Determine that leading 4200 meet the first communication protocol.Additionally, being configured to be matched somebody with somebody according to the communication equipment of the first communication protocol operations The repetition for being detected based on HEW-SIG1 fields 3004,3016 is set to, leading 4200 models for meeting the first communication protocol are determined Enclose mode of extension.

Leading 4204 is similar with leading the 4104 of Figure 41, and the element of identical numbering is not carried out for purposes of brevity in detail It is thin to discuss.In embodiment, L-LTF fields 4112 correspond to the modified LTF fields 2304 of Figure 23, and in embodiment In, L-SIG 4120 leaves signal field 2306 corresponding to the modified of Figure 23.In this embodiment, the first communication protocols are met The receiving device of view can perform first cross-correlation of L-LTF 4108 by using the long training sequence of legacy communication protocols And the modified long training sequence of the first communication protocol used in embodiment as described by above for Figure 23 and hold Second cross-correlation of row L-LTF fields 4112 meets the first communication protocol detecting the data cell including leading 4104.With class As mode, meeting the receiving device of the first communication protocol can detect that the data cell including leading 4104 meets the first communication The normal mode of agreement.

In embodiment, L-LTF fields 2916 correspond to the modified LTF fields 2304 of Figure 23, and in embodiment In, L-SIG 2924 leaves signal field 2306 corresponding to the modified of Figure 23.In this embodiment, the first communication protocols are met The receiving device of view can perform first cross-correlation of L-LTF 2912 by using the long training sequence of legacy communication protocols And the modified long training sequence of the first communication protocol used in embodiment as described by above for Figure 23 and hold Second cross-correlation of row L-LTF fields 2916 meets the first communication protocol detecting the data cell including leading 4200.

Figure 43 is to meet first according to another embodiment compared with the leading part 2904 for meeting legacy protocol The diagram of the leading part 4300 of example PHY of communication protocol.Additionally, PHY leading 4300 also corresponds to the first communication protocol Scope mode of extension.Figure 43 is also included compared with the leading part 2904 for meeting legacy protocol, according to another embodiment The leading part 4304 of example PHY for meeting the first communication protocol diagram.Additionally, PHY leading 4304 also corresponds to first The normal mode of communication protocol.

In embodiment, the Network Interface Unit 16 of AP 14 is configured to be modulated to visitor via the OFDM according to embodiment Family station 25-1 generates and sends the data cell including PHY leading 4300 or PHY leading 4304.In embodiment, client The Network Interface Unit 27 of 25-1 of standing is configured with technology discussed below and determines to include leading 4300 or leading 4304 data cell meets the first communication protocol.In embodiment, the Network Interface Unit 27 of client stations 25-1 is configured to Being determined using technology discussed below includes that leading 4300 data cell meets scope mode of extension and including leading 4304 data cell meets normal mode.

In embodiment, the Network Interface Unit 27 of client stations 25-1 is additionally configured to that bag is generated and sent to AP 14 Include the data cell of PHY leading 4300 or PHY leading 4304.In embodiment, the Network Interface Unit 16 of AP 14 is configured It is to determine that the data cell for including PHY leading 4300 or PHY leading 4304 meets first and leads to using technology discussed below Letter agreement.In embodiment, the Network Interface Unit 16 of AP 14 be configured with technology discussed below determine include it is front The data cell for leading 4300 meets scope mode of extension and the data cell including leading 4304 meets normal mode.

According to embodiment, including the data cell of PHY leading 4300 meets the first communication protocol and occupies 20MHz bands It is wide.In various other embodiments, meet the first communication protocol and including the leading data cell similar with leading 4300 Can take up other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other are suitable Bandwidth.According to embodiment, including the data cell of PHY leading 4101 meets the first communication protocol and occupies 20MHz bandwidth. In various other embodiments, meet the first communication protocol and can account for including the leading data cell similar with leading 4304 According to other suitable bandwidth, such as 40MHz, 80MHz, 160MHz, 320MHz, 640MHz or other suitable bandwidth.

Leading 4300 is similar with leading the 2900 of Figure 29, and the element of identical numbering is not carried out for purposes of brevity in detail It is thin to discuss.Legacy devices can decode that L-SIG 206/306/506 and determination includes the PHY data unit of PHY leading 4300 Length.For example, in embodiment, L-SIG 206/306/506 includes being set to the PHY numbers for indicating to include PHY leading 4300 According to the length field of the value of the length of unit.

Except data cell 4300 omits the second (duplication) L-SIG fields 2928 and including automatic detection OFDM symbol Outside 4308, data cell 4300 is similar with the data cell 2900 of Figure 29.In embodiment, meet connecing for the first communication protocol Receiving unit can be based on and detect the automatic detection OFDM symbol 4308 in leading 4300 to detect the data including leading 4300 Unit meets the first communication protocol.In the illustrated embodiment, automatic detection symbol 4308 immediately follows follows L-SIG fields 206/306/506.In embodiment, automatic detection symbol 4308 and its corresponding OFDM in Legacy Data cell format 2904 Symbol aligned and using BPSK modulation be modulated.In embodiment, the receiving device for meeting the first communication protocol being capable of base The data cell including leading 4300 is detected in the automatic detection OFDM symbol 4308 in leading 4300 is detected meet first Communication protocol, as discussed with regard to Figure 37.

Leading 4304 is similar with leading the 4104 of Figure 41, and the element of identical numbering is not carried out for purposes of brevity in detail It is thin to discuss.In embodiment, L-LTF fields 4112 correspond to the modified LTF fields 2304 of Figure 23, and in embodiment In, L-SIG 4120 leaves signal field 2306 corresponding to the modified of Figure 23.In this embodiment, the first communication protocols are met The receiving device of view can perform first cross-correlation of L-LTF 4108 by using the long training sequence of legacy communication protocols And the modified long training sequence of the first communication protocol used in embodiment as described by above for Figure 23 and hold Second cross-correlation of row L-LTF fields 4112 meets the first communication protocol detecting the data cell including leading 4304.With class As mode, meeting the receiving device of the first communication protocol can detect that the data cell including leading 4304 meets the first communication The normal mode of agreement.

In another embodiment, L-LTF fields 2916 correspond to the modified LTF fields 2304 of Figure 23, and in reality In applying example, L-SIG 2924 leaves signal field 2306 corresponding to the modified of Figure 23.In this embodiment, HEW associations are met The receiving device of view can perform first cross-correlation of L-LTF 2912 by using the long training sequence of legacy communication protocols And the modified long training sequence of the first communication protocol used in embodiment as described by above for Figure 23 and hold Second cross-correlation of row L-LTF fields 2916 meets the first communication protocol detecting the data cell including leading 4300.

In various other embodiments, will be all with what is utilized such as above for Fig. 9 A- Figure 28 technique described above Technology as described by above for Figure 29-Figure 40 B is combined so that the receiver for meeting the first communication protocol can determine I) data cell meets the first communication protocol, and ii) determine that data cell meets a variety of moulds of the first communication protocol Which pattern in formula (for example, scope mode of extension, normal mode etc.).

In some embodiments that wherein SIG fields (for example, L-SIG, HEW-SIG1 etc.) are replicated, using the sound of time-varying Adjust mapping.For example, in embodiment, using half-band width cyclic shift tone mapper.In embodiment, SIG OFDM symbols Tone on number (time t1) is corresponded to：

SIGk(t₁)=s_k(t1)=s_k(equation 4)

Wherein, SIG_kIt is k-th tone of SIG OFDM symbols, and s_kIt is k-th to SIG OFDM symbols to be mapped BPSK symbols.In embodiment, second (duplication) SIG OFDM symbols (time t₂) on tone correspond to：

SIGk(t₂)=s_k(t2)=s_{(k+N/2)mod N}(equation 5)

Wherein, N is the number of the tone in SIG OFDM symbols.Therefore, in embodiment, in a SIG OFDM symbols Middle BPSK symbols s is sequentially mapped tone, and in the half of tones of the identical BPSK symbols s in the 2nd SIG OFDM symbols By cyclic shift.In other embodiments, the Tone Map of another suitable time-varying be used to realize across different SIG OFDM The time diversity of symbol.

In embodiment, realized using the different interleaver of the bit for the identical coding in two OFDM symbols Across the time diversity of different SIG OFDM symbols.In other embodiments, utilize for realizing being accorded with across different SIG OFDM Number time diversity other suitable technologies.

Wherein in leading some embodiments for meeting the first communication protocol, meet the first communication protocol it is leading in L- SIG fields corresponding to leave it is leading in L-SIG be multiplied by sequence ck：

L-SIG_k ^(HEW)=c_k·L-SIG_k ^(HEW)(equation 6)

Wherein k is tone index.In embodiment, sequence c_kIt is the sequence of the value with ± 1.

In certain embodiments, one or more further L-SIG are included meeting the leading of the first communication protocol Field.

In certain embodiments, HEW-SIG fields include data cell Duration Information, the byte of such as data cell Number, the number of the OFDM symbol of data cell etc..

In certain embodiments, to meet leave it is leading in the HEW-SIG fields of SIG fields (for example, SIGA) carry out It is configured so that in leading the duplication comprising HEW-SIG fields will cause legacy devices (for example, IEEE 802.11ac receptions Device) SIGA crc errors are generated with 100% possibility.For example, in various embodiments, the bit in HEW-SIG fields is added Disturb, including being set to guarantee SIGA CRC by 1 bit field in mistake etc..In another embodiment, HEW-SIG fields It is designed to include the bit corresponding to the invalid mode in legacy protocol.

In embodiment, a kind of method is for generating physical layer (PHY) data cell for via the biography of communication channel Defeated, PHY data unit meets the first communication protocol.The method is included at the first communication equipment and generates for PHY data unit PHY it is leading, including：Generate signal field, by the duplication of signal field and signal field be included in PHY it is leading in, and lattice Formula PHY is leading so that PHY leading Part I is by meeting the second communication protocol but do not meet the second of the first communication protocol Communication equipment decodable code, to be based on the leading Part I of PHY determining the duration of PHY data unit.The method is also It is included at the first communication equipment and generates PHY data unit with comprising PHY is leading and PHY payload.

PHY leading Part II is that the second communication equipment is un-decodable.

Hardware can be utilized, the processor of firmware instructions is performed and is performed the processor or its any combinations reality of software instruction At least some in existing various pieces as described above, operation and technology.When using the process for performing software or firmware instructions When device is realized, either firmware instructions can be stored in any non-transient tangible computer computer-readable recording medium or media such as magnetic to software Disk, CD, random access memory (RAM), read-only storage (ROM), flash memory, tape etc..Software or firmware refer to Order can include that the machine for causing one or more processors to perform various actions when executed by one or more processors can Reading instruction.

When implemented in hardware, hardware can include it is following in one or more：It is discrete assembly, integrated circuit, special Integrated circuit (ASIC), PLD (PLD) etc..

Although describing the present invention by reference to the particular example for being intended to the only illustrative and not limiting present invention, do not taking off In the case of the scope of the present invention, the disclosed embodiments can be made a change, added and/or be deleted.

Claims

1. a kind of for generating physical layer PHY data unit for via the method for the transmission of communication channel, the PHY data sheets Unit meets the first communication protocol, and methods described includes：

Generate at the first communication equipment it is leading for the PHY of the PHY data unit, including：

Generate signal field,

By the duplication of the signal field and the signal field be included in the PHY it is leading in, and

It is leading to the PHY to be formatted so that the PHY leading Part I is by meeting the second communication protocol but be not inconsistent Close the second communication equipment decodable code of first communication protocol, to be based on the leading Part I of the PHY come really The duration of the fixed PHY data unit；And

The PHY data unit is generated at first communication equipment with comprising the PHY is leading and PHY payload.

2. method according to claim 1, wherein：

The signal field is to leave signal field by second communication equipment is decodable；

The signal field of leaving is comprised in the leading Part I of the PHY；And

It is described to leave information of the signal field comprising the duration for indicating the PHY data unit.

3. method according to claim 2, wherein generating, the PHY for the PHY data unit is leading also to be included：

Generation meets the other signal field of second communication protocol, and

The other signal field is included in the leading Part II of the PHY.

4. method according to claim 3, wherein the PHY leading Part II is second communication equipment Un-decodable.

5. method according to claim 3, wherein generating, the PHY for the PHY data unit is leading also to be included：

The duplication of the other signal field is included in the leading Part II of the PHY.

6. method according to claim 1, wherein generating, the PHY for the PHY data unit is leading also to be included：

7. method according to claim 1, wherein：

The signal field is the first signal field；And

Generate that the PHY for the PHY data unit is leading also to be included：

Generate by the decodable secondary signal field of second communication equipment, wherein the secondary signal field includes instruction institute The information of the duration of PHY data unit is stated,

The secondary signal field is included in the leading Part I of the PHY, and

First signal field is included in the leading Part II of the PHY.

8. method according to claim 7, wherein the PHY leading Part II is second communication equipment Un-decodable.

9. method according to claim 1, wherein：

For the PHY data unit the PHY it is leading be generated with the PHY leading Part I just Hand over and include between frequency-domain OFDM symbol corresponding first protection interval；And

Methods described is additionally included at first communication equipment and generates the PHY payload with the PHY payload OFDM symbol between include corresponding second protection interval, wherein each second protection interval have than each the first protection interval The longer duration.

10. method according to claim 9, wherein for the PHY data unit the PHY it is leading be generated with Corresponding second protection interval is included between OFDM symbol in the PHY leading Part II.

A kind of 11. first communication equipments, including：

Network Interface Unit with one or more integrated circuits, one or more of integrated circuits are configured to：

The PHY of the physical layer PHY data unit that generation meets the first communication protocol is leading, including；

Generate signal field,

The PHY data unit is generated with comprising the PHY is leading and PHY payload.

12. first communication equipments according to claim 11, wherein：

One or more of integrated circuits are configured to：By it is described leave signal field be included in the PHY it is leading described in In Part I；And

13. communication equipments according to claim 12, wherein one or more of integrated circuits are configured to：

Generation meets the other signal field of second communication protocol, and

The other signal field is included in the leading Part II of the PHY.

14. first communication equipments according to claim 13, wherein the PHY leading Part II is described Two communication equipments are un-decodable.

15. communication equipments according to claim 13, wherein one or more of integrated circuits are configured to：

16. communication equipments according to claim 11, wherein one or more of integrated circuits are configured to：

17. first communication equipments according to claim 11, wherein：

The signal field is the first signal field；And

One or more of integrated circuits are configured to：

The secondary signal field is included in the leading Part I of the PHY, and

First signal field is included in the leading Part II of the PHY.

18. first communication equipments according to claim 17, wherein the PHY leading Part II is described Two communication equipments are un-decodable.

19. communication equipments according to claim 11, wherein one or more of integrated circuits are configured to：

Generate leading with orthogonal in the PHY leading Part I for the PHY of the PHY data unit Corresponding first protection interval is included between frequency-domain OFDM symbol；And

Generate the PHY payload to include between the OFDM symbol in the PHY payload between the corresponding second protection Every wherein each second protection interval has the duration longer than each the first protection interval.

20. first communication equipments according to claim 19, wherein one or more of integrated circuits are configured to：It is raw Into between the leading OFDM symbols with the PHY leading Part II of the PHY include corresponding second protection interval.