Patent Description:
With development of the mobile Internet and popularization of intelligent terminals, data traffic increases rapidly. A wireless local area network (WLAN, Wireless Local Area Network) becomes one of mainstream mobile broadband access technologies by virtue of advantages of a high rate and low costs.

To significantly improve a service transmission rate of a WLAN system, the next-generation Institute of Electrical and Electronics Engineers (IEEE, Institute of Electrical and Electronics Engineers) <NUM>. 11ax standard further uses an Orthogonal Frequency Division Multiple Access (OFDMA, Orthogonal Frequency Division Multiple Access) technology on a basis of an existing Orthogonal Frequency Division Multiplexing (OFDM, Orthogonal Frequency Division Multiplexing) technology. The OFDMA technology divides time-frequency resources of a wireless channel of an air interface into multiple orthogonal time-frequency resource units (RB, Resource Block). The RBs are shared in terms of time and are orthogonal in terms of a frequency field. In <NUM> ax, a transmission bandwidth allocated to users is referred to as a resource unit, and therefore, is only represented by "resource unit" subsequently. "Spec Framework", IEEE draft, <NUM>-<NUM>-<NUM>-<NUM>-00ax-SPEC-FRAMEWORK, discloses that a High-Efficiency Signal Field B, HE-SIG-B is encoded on a basis of <NUM>. For bandwidths equal to or larger than <NUM>, the number of the <NUM> sub-bands carrying different content is two and with the structure "<NUM>. HE-SIG-B has a common field followed by a user-specific field. "SIG-B Encoding Structure", IEEE draft, <NUM>-<NUM>-<NUM>-<NUM>-00ax-sig-b-encoding-structure, discloses that a Signal Field B, SIG-B, is encoded on a per-<NUM> basis and the common and per-user blocks are separated in the bit domain in a "<NUM><NUM>" structure. "HE SIG-B structure", IEEE draft, <NUM>-<NUM>-<NUM>-<NUM>-00AX-HE-SIG-B-STRUCTURE, discloses that a High-Efficiency Signal Field B, HE SIG-B, does not have any OFDM symbol duplicated in each <NUM>, the common field includes the information for all of designated stations to receive the physical layer conformance procedure (PLCP) protocol data unit (PPDU) in corresponding bandwidth, and the user-specific field consists of multiple sub-fields that do not belong to the common field, where one or multiple of those sub-fields are for each designated receiving station. Further relevant prior-art can be found in <CIT>.

The present invention is defined by the attached independent claims. Other preferred embodiments may be found in the dependent claims.

In a next-generation wireless local area network, signaling overheads can be reduced by using the methods provided in the embodiments of the present invention.

To describe the technical solutions in the embodiments of the present invention or in the prior art more clearly, the following briefly describes the accompanying drawings required for describing the embodiments or the prior art. Apparently, the accompanying drawings in the following description show some embodiments of the present invention, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.

The following clearly and completely describes the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are a part rather than all of the embodiments of the present invention. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. For ease of understanding, terms that possibly appear in the following embodiments are explained as follows:.

An access point (AP, Access Point) may also be referred to as a wireless access point, a bridge, a hotspot, or the like, and may access a server or a communications network.

A station (STA, Station) may also be referred to as a user, and may be a wireless sensor, a wireless communications terminal, or a mobile terminal, such as a mobile phone (or referred to as a "cellular" phone) supporting a WiFi communication function and a computer with a wireless communication function. For example, the station may be a portable, pocket-sized, handheld, computer built-in, wearable, or in-vehicle wireless communications apparatus that supports the WiFi communication function and exchanges communications data such as voice and data with a radio access network.

Referring to <FIG> is a diagram of a network architecture of a wireless local area network, including the foregoing AP <NUM> and at least one station STA <NUM>. Various apparatuses in the foregoing system may comply with a standard protocol of a next-generation wireless local area network, such as <NUM>.

11ax, there are multiple resource unit sizes, including a resource unit size of <NUM> subcarriers, a resource unit size of <NUM> subcarriers, a resource unit size of <NUM> subcarriers, a resource unit size of <NUM> subcarriers, and the like.

At a <NUM> bandwidth, a resource unit size is limited to <NUM>, <NUM>, <NUM>, or <NUM> subcarriers. As shown in <FIG>, a resource unit with the size of <NUM> in the center crosses direct current subcarriers, and the direct current subcarriers are shown as a small gap in the center of the <FIG> (subcarrier frequency indexes -<NUM>, <NUM>, and <NUM>). The first layer shows location of <NUM> resource units with the size of <NUM>. The second layer show location of <NUM> resource units with the size of <NUM> and <NUM> resource unit with the size of <NUM>. The third layer shows location distribution of <NUM> resource units with the size of <NUM> and <NUM> resource unit with the size of <NUM>. The fourth layer show location of <NUM> resource unit with the size of <NUM>, and the resource unit with the size of <NUM> is the full <NUM> bandwidth. A tone allocation of a <NUM> frequency domain may be a combination of any resource units shown in the four layers, occupying a frequency spectrum of <NUM> subcarriers. One example is shown in <FIG>, the <NUM> bandwidth is allocated as four resource units (<NUM>+<NUM>+<NUM>+<NUM>). When performing scheduling, the AP can assign only one resource unit to each user, but may assign a same resource unit to multiple users. The users sharing one resource unit transmit data in spatial flows respectively, in a MU-MIMO (multi-user Multiple Input Multiple Output, multi-user multiple-input multiple-output) manner.

At a <NUM> bandwidth, a resource unit size is limited to <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> subcarriers. As shown in <FIG>, a small gap shown in the center are direct current subcarriers. The first layer shows location of <NUM> resource units with the size of <NUM>. The second layer shows location of <NUM> resource units with the size of <NUM> and <NUM> resource units with the size of <NUM>. The third layer shows location of <NUM> resource units with the size of <NUM> and <NUM> resource units with the size of <NUM>. The fourth layer shows location of <NUM> resource units with the size of <NUM>, and the resource unit with the size of <NUM> is a <NUM> bandwidth. The fifth layer is one resource unit with the size of <NUM>, and the resource unit with the size of <NUM> is a full <NUM> bandwidth. A tone allocation of a <NUM> frequency domain may be a combination of any resource units shown in the five layers, occupying a frequency spectrum of <NUM> subcarriers, and only one the resource unit can be assigned to each user.

At an <NUM> bandwidth, a resource unit size is limited to <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> subcarriers. As shown in <FIG>, a tone allocation of the <NUM> bandwidth is shown in six layers, a resource unit with the size of <NUM> in the center crosses direct current subcarriers, and a small gap in the center is shown as the direct current subcarriers. The first layer shows location of <NUM> resource units with the size of <NUM>. The second layer shows location of <NUM> resource units with the size of <NUM> and five resource units with the size of <NUM>. The third layer shows location of <NUM> resource units with the size of <NUM> and <NUM> resource units with the size of <NUM>. The fourth layer shows location of <NUM> resource units with the size of <NUM> and <NUM> resource unit with the size of <NUM>, and the resource unit with the size of <NUM> is a <NUM> bandwidth. The fifth layer shows <NUM> resource units with the size of <NUM> and <NUM> resource unit with the size of <NUM>, and the resource unit with the size of <NUM> is a <NUM> bandwidth. The sixth layer shows location of one resource unit with the size of <NUM>, and the resource unit with the size of <NUM> is an <NUM> bandwidth. A tone allocation of a <NUM> frequency domain may be a combination of any resource units shown in the five layers, occupying a frequency spectrum of <NUM> subcarriers,, and only one resource unit an be assigned to each user.

<FIG> is a possible packet structure (a packet structure PPDU in multi-user transmission) in <NUM>. 11ax, and shows that the AP simultaneously transmits data to multiple STAs by using multiple resource units in a DL (Downlink, downlink) OFDMA manner. Several STAs may also share a same resource unit, and transmit data in their spatial flows respectively in the MU-MIMO manner.

The packet structure (Packet structure) in <NUM>. 11ax firstly comprises: a legacy preamble, that comprises a legacy short training field (legacy short training field, L-STF), a legacy long training field (legacy long training field, L-LTF), and a legacy signal field (legacy signal field, L-SIG), to ensure backward compatibility, so that a STA of an earlier-version standard can receive and decode the legacy preamble. In addition, a repeated legacy signal field (Repeated L-SIG) is also included, which is used to perform automatic detection for <NUM>. 11ax and increase robustness of the L-SIG. An HE-SIG-A (High Efficiency Signal Field A, high Efficiency signal field A) is used to carry information, such as a bandwidth and an AP identifier (AP ID, also referred to as BSS Color, BSS color), that is in a current BSS (Basic Service Set, basic service set) and OBSS (Overlapped BSS, overlapped basic service set) and that is read by a STA, as shown in <FIG>,. An HE-SIG-B (High Efficiency Signal Field B, high Efficiency signal field B) is mainly used to carry resource scheduling information that is in a current BSS and that is read by a STA. The following are an HE-STF (High Efficiency Short Training Field, high Efficiency short training field) and an HE-LTF (High Efficiency Long Training Field, high Efficiency long training field), which are respectively used to perform AGC (Automatic Gain Control, automatic gain control) and channel measurement of MIMO (Multiple Input Multiple Output, multiple-input). The HE-LTF field may include multiple HE-LTF symbols, which are used to perform channel measurement for multiple space-time streams. The last is a Data part, and is used to bear a MAC frame.

As shown in <FIG>, the AP allocates a full bandwidth into multiple resource units, and uses the multiple resource units to trans-ceive data with multiple STAs. For a STA to determine whether the STA itself is a target STA and for a target STA to determine a frequency location in which data is carried and a physical layer parameter for receiving data, the AP needs to indicate resource scheduling information. For downlink multi-user transmission, the HE-SIG-B generally comprises resource scheduling information of multiple users, to instruct multiple STAs to receive data. <FIG> is a possible structure of an HE-SIG-B, and the structure comprises a common field (common part) and a user specific field (dedicated part). The common field comprises some common information that all target STAs need to read, such as indication information of resource unit(s) allocation (Resource allocation Signaling, RA Signaling). The user specific field comprises scheduling information for a group of STAs assigned with a same resource unit to read, or scheduling information for each one STA to read. The indication information of resource allocation in the common field may have multiple possible structures. One relatively high-efficiency manner is to store, indices for all possible combinations into a table, through storing each index and the corresponding combination of resource units. Multiple resource unit sizes are currently defined in <NUM>. 11ax, and comprises <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and the like according to a number of subcarriers (for details, refer to BACKGROUND <NUM>. <FIG> shows all possible combination manners for OFDMA resource units at a full <NUM> bandwidth. For <NUM>, a resource unit size may be <NUM>, <NUM>, <NUM>, and <NUM> subcarriers. There are totally <NUM> allocations, which correspond to <NUM> indices. Provided that the common part carries ceil(log225)=<NUM> bits, all possible cases of <NUM> can be carried, where ceil represents rounding up. For a case with a full bandwidth being <NUM>, <NUM>, or <NUM>, based on the multiple indices, an indication for each <NUM> is performed respectively (that is, multiple pieces of RA Signaling).

In some other solutions, the OFDMA resource allocation indication also indicates a transmission situation of multi-user MIMO (Multiple-user MIMO, MU-MIMO), that is, when data for multiple users are included on one resource unit, the specific number of users is also indicated (as shown in <FIG>). When a resource unit is sufficiently large, for example, comprises <NUM> subcarriers, multi-user transmission is further allowed on the resource unit by using MU MIMO. Therefore, a table that comprises a more comprehensive allocation manner is proposed in some embodiments, and compared with the former embodiment, requires more bits for indication the number of users; wherein resource units marked by <NUM> - <NUM> are resource units allowable for MU-MIMO transmission, and indices are respectively provided for each case with one to eight users in the table. Referring to <FIG>, the resource units marked by <NUM> - <NUM> are included.

A table may be generated for the resource allocation manner in <FIG>, also on a basis of <NUM>. The table comprises an indication of a resource unit with a size greater than <NUM> (cases marked by dark green and red) in addition to an indication of a number of users on a resource unit allowable for MU-MIMO. For a case with a full bandwidth of <NUM>, <NUM>, or <NUM>, based on the multiple indices, an indication for each <NUM> is performed respectively (that is, multiple pieces of RA Signaling).

In the user specific field, each piece of user scheduling information has two possible structures, as shown in <FIG>. A structure in <FIG> represents a scheduling information structure in a single-user mode. The single-user mode means that a current STA exclusively occupies one resource unit. <FIG> represents a scheduling information structure in a multi-user mode. The multi-user mode means that a current STA does not exclusively occupy one resource unit, and some other STAs share one resource unit with the current STA in a MU-MIMO manner.

The structure in <FIG> comprises: a station identifier (STA Identifier, STA ID) or a station partial identifier (STA Partial Identifier, STA PAID), a modulation and coding scheme (Modulation and Coding Scheme, MCS for short), used to indicate a modulation and coding scheme, a number of space-time streams (Number of Space-Time Stream, NSTS for short), used to indicate a number of used space-time streams, a coding manner (Coding), used to indicate whether an LDPC coding manner is used, space time block coding (Space Time Block Coding, STBC for short), used to indicate whether STBC is used, and beamforming (Beamforming, TxBF), used to indicate whether a beamforming technology is used. In addition, the structure may also include a cyclic redundancy code (Cyclic Redundancy Code, CRC for short), used to store a CRC check bit, and a tail bit (Tail), used to store a <NUM>-bit tail of a binary convolutional code (Binary Convolution Code, BCC for short).

The structure in <FIG> comprises a station identifier (STA Identifier, STA ID) or a station partial identifier (STA Partial Identifier, STA PAID), a modulation and coding scheme (Modulation and Coding Scheme, MCS for short), used to indicate a modulation and coding scheme, a location of the first space-time stream (first Stream index), used to indicate a sequence number of the used first space-time stream (because a STA only transmits data in a space-time stream in which the STA is located, a start location of the space-time stream of the STA needs to be learned), a number of space-time streams (Number of Space-Time Stream, NSTS for short), used to indicate a number of used space-time streams, and a coding manner (Coding), used to indicate whether an LDPC coding manner is used. In addition, the structure may also include a cyclic redundancy code (Cyclic Redundancy Code, CRC for short), used to store a CRC check bit, and a tail bit (Tail), used to store a <NUM>-bit tail of a binary convolutional code (Binary Convolution Code, BCC for short).

When a transmission bandwidth is greater than <NUM>, a preamble part needs to be transmitted over each <NUM>. Parts comprising the legacy preamble, the repeated L-SIG, and the high Efficiency signal field A are duplicated and transmitted over each <NUM>. The high Efficiency signal field B part uses a partial duplication mode. Transmission over <NUM> is used as an example. A transmission mode of the preamble part is specifically shown in <FIG>.

It may be seen that, as shown in <FIG>, the HE-SIGB carries different content at an odd-numbered <NUM> and at an even-numbered <NUM>, but carries same content at each odd-numbered <NUM> (a first <NUM> and a third <NUM>) and carries same content at each even-numbered <NUM> (a second <NUM> and a fourth <NUM>). An HE-SIGB at an odd-numbered <NUM> is denoted as SIGB-<NUM>, and an HE-SIGB at an even-numbered <NUM> is denoted as SIGB-<NUM>. For content included in the SIGB-<NUM> and the SIGB-<NUM>, refer to an introduction in BACKGROUND <NUM>. <NUM>, comprises a common field and a user specific field. The SIGB-<NUM> comprises indication information of resource allocation (RA signaling) over the first <NUM> sub-channel and the third <NUM> sub-channel and user scheduling information for the transmission over the first and the third <NUM> sub-channel. The SIGB-<NUM> comprises indication information of resource allocation (RA signaling) over the second <NUM> sub-channel and the fourth <NUM> sub-channel and user scheduling information for the transmission over the second and the fourth <NUM> sub-channel. For a <NUM> bandwidth transmission, only one HE-SIGB (SIGB-<NUM>) is comprised. For a <NUM> bandwidth transmission, SIGB-<NUM> and SIGB-<NUM> are comprised, but both the SIGB-<NUM> and the SIGB-<NUM> comprises a resource allocation indication and user scheduling information over only one <NUM> sub-channel. The SIGB-<NUM> comprises a resource allocation indication and user scheduling information over the first <NUM> (an odd-numbered <NUM>), and the SIGB-<NUM> comprises a resource allocation mode indication and user scheduling information over the second <NUM> (an even-numbered <NUM>).

In general, some solutions are needed to reduce overheads of the HE-SIGA or the HE-SIGB further.

In Preferred Embodiment <NUM>, a part of an HE-SIGA field may be reused. Further, an indication of a number of users in the common field of the HE-SIGB may be omitted.

Referring to <FIG>, generally, in an HE-SIGA structure, "#sym HE-SIGB" field is used to indicate a number of symbols in the HE-SIGB.

In Preferred Embodiment <NUM>, when a current transmission mode is full bandwidth MU-MIMO or single-user transmission, "#sym HE-SIGB" field is used to indicate a number of currently scheduled users, and is no longer used to indicate the number of the symbols in the HE-SIGB. In this case, an common field of the HE-SIGB may not include information for indicating the number of the currently scheduled users. This can reduce some overheads.

In this solution, the HE-SIGA comprises an indication of MCS of the HE-SIGB, besides the "#sym HE-SIGB" field indicating the number of the currently scheduled users. In this way, when needed, the number of the symbols in the HE-SIGB may also be calculated out on a sending side or a receiving side according to the number of the currently scheduled users. For brevity, reusing the field "#sym HE-SIGB" field does not cause a loss of related information.

Specifically, a bit overhead of each piece of user scheduling information is fixed , therefore, when obtaining a "#sym HE-SIGB" indicating the number of the scheduled users, a receive end is capable to obtain a total bit overhead of the user scheduling information field. With reference to the MCS of HE-SIGB indicated in the HE-SIGA, the receive end is capable to obtain a number of HE-SIGB symbols occupied by the total user scheduling information field, and further accurately obtain a location in which the HE-SIGB ends.

Referring to <FIG> is a preferred structure of an HE-SIGA/B in this embodiment.

The HE-SIGA comprises an indication for a non-OFDMA transmission and an indication for the number of scheduled users. The HE-SIGB may not include information for resource unit(s) allocation and may not include information about the number of the users.

It should be noted that Preferred Embodiment <NUM> is a special case for current transmission, that is, the current transmission is a full bandwidth MU-MIMO or a single-user transmission mode; or, it is a case that resource allocation indication information in a common field of a current HE-SIGB may be omitted. Specifically, for how to obtain that the current transmission is a special case, a method in which the HE-SIGA comprises a transmission mode indication may be used, or, other possible implementation methods may also be used, such as Preferred Embodiment <NUM> or <NUM> in the present invention. The transmission mode indication is used to indicate that the current transmission is an OFDMA transmission mode or a non-OFDMA transmission mode. The non-OFDMA transmission mode is a full bandwidth MU-MIMO, or a single-user transmission.

Specifically, in a full bandwidth MU-MIMO or a single-user transmission, the number of all users does not exceed eight. Therefore, this preferred embodiment has following examples.

Example <NUM>: The "#sym HE-SIGB" field occupies <NUM> bits. A first two bits may be used to indicate the number of scheduled users in the SIGB-<NUM>, and the last two bits may be used to indicate the number of scheduled user in the SIGB-<NUM>. That is, the field may indicate the number of the user fields comprised in a user specific field of each SIGB. Referring to the foregoing introduction of the HE-SIGB (SIGB-<NUM> and SIGB-<NUM>), the foregoing indication manner may be applicable to a case with a bandwidth greater than <NUM>.

Example <NUM>: Alternatively, all or partial bits of the "#sym HE-SIGB" field may be used to indicate a total number of scheduled users included in the HE-SIGB. Certainly, a number of bits occupied by the "#sym HE-SIGB" field is not limited to <NUM>, and for example, may be <NUM>. The foregoing method may be applicable to various cases of different bandwidths.

Example <NUM>: Alternatively, all or partial bits of the "#sym HE-SIGB" field may be used to indicate the greater one, of the number of scheduled users in the SIGB-<NUM>, and the number of scheduled users in the SIGB-<NUM>. The foregoing method may be applicable to various cases of different bandwidths.

In Preferred Embodiment <NUM>, a method is proposed and comprises a type of special information for resource unit(s) allocation (that is, special Resource Allocation, RA). The special RA is used to indicate that there is no corresponding user scheduling information field in a subsequent user specific field. An indication of the special RA may be plausibly understood as that the number of users scheduled on a current resource unit is zero, or, the current transmission is in an invalid resource allocation mode.

After obtaining the indication of the special resource allocation mode, a receive end accordingly obtains that for this <NUM> subchannel, no user scheduling information fields exist in a user specific field corresponding to this <NUM> subchannel. In this case, the receive end may ignore this resource allocation mode indication information.

<FIG> is used as an example for specific description. RA-<NUM> indicates that no user scheduling information corresponding to RA-<NUM> exists in a subsequent user specific field. It may be understood as indicating an authentic or a fake resource allocation mode. For example, a current resource unit is a resource unit of <NUM> or a resource unit of <NUM>, and the resource unit is assigned to "<NUM>" user. This RA-<NUM> may be understood as an invalid resource allocation mode, and there is no subsequent user scheduling information field that corresponds to the RA-<NUM>. The receive end may directly ignore indication information of this invalid resource allocation mode. RA-<NUM> comprises an authentic resource allocation mode, that is, a resource unit with a size of <NUM> is assigned for <NUM> users MU-MIMO transmission. In this way, the SIGB-<NUM> only comprises <NUM> pieces of user scheduling information field for the third <NUM> subchannel, and the SIGB-<NUM> comprises <NUM> pieces of user scheduling information field for the second (together with the first) <NUM> subchannel and the fourth <NUM> subchannel. Compared with <FIG>, the HE-SIGB in <FIG> reduces overheads of user scheduling information field in length.

The following describes an effect of the foregoing preferred embodiment by comparison with an example in <FIG>. In the example, similarly, the AP assigns a <NUM> subchannel (a <NUM> resource unit ) for <NUM> users MU-MIMO transmission , assigns a <NUM> subchannel (resource units with <NUM> + <NUM> + <NUM> + <NUM> + <NUM> + <NUM>) for <NUM> users OFDMA transmission, and assigns a <NUM> subchannel (a <NUM> resource unit ) for <NUM> users MU-MIMO transmission. Referring to the RA indication method shown in the <FIG>, if this preferred embodiment is not used, it may be obtained that RA-<NUM> indicates that a <NUM> resource unit (<NUM>) is in use over the first <NUM>, to which n1 users are assigned; RA-<NUM> indicates that a <NUM> resource unit (<NUM>) is in use over the second <NUM>, to which n2 users are assigned; RA-<NUM>/<NUM> indicates the same resource unit with the size of <NUM> (<NUM>), and the number of users indicated in the RAs is n1+n2=<NUM>. The four users is assigned to use the resource unit with the size of <NUM>, that is, two <NUM>. Therefore, scheduling information of the <NUM> users may be considered as belonging to either <NUM> subfield. RA-<NUM> indicates that the third <NUM> is allocated into six resource units, that is, resource units respectively with sizes of <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. Each resource unit is to be used by <NUM> user, and there are <NUM> users totally. RA-<NUM> indicates that a resource unit with a size of <NUM> (<NUM>) is in use over the fourth <NUM>, and <NUM> users are assigned.

In <FIG>, because the RA indication does not include a case with zero users, the number n1 of users indicated by RA-<NUM> and the number n2 of users indicated by RA-<NUM> are at least greater than or equal to <NUM>. In this way, at least one piece of user scheduling information, corresponding to RA-<NUM> or RA-<NUM>, needs to be comprised in a user specific field. However, since there are <NUM> users scheduled on the third <NUM>, SIGB-<NUM> already necessarily comprises <NUM> pieces of user scheduling information field over the third <NUM>; while an accumulative number of users over the first, the second, and the fourth <NUM> is also <NUM>. Consequently, by using the preferred embodiment, as shown in <FIG>, the SIGB-<NUM> only comprises scheduling information for the <NUM> users over the third <NUM>, and the SIGB-<NUM> comprises scheduling information for the remaining <NUM> users. In this way, a number of overall symbols in the HE-SIGB is smallest.

Further, the indication of the foregoing special resource allocation mode may use various possible specific indication methods.

For example, an RA indication uses the above-mentioned manner of performing an index indication according to a stored table. Such a table of resource allocation mode comprises one type of such a special resource allocation mode. An index corresponding to the above mode is transmitted to indicate that the current transmission is a special resource allocation mode. The index of the special mode may be an unused index.

For another example, for an RA indication that does not use a storage table manner, specifically, a special combination of resource indication bits, or one of the bits, may be used to indicate the foregoing special resource allocation mode.

In this preferred embodiment, the HE-SIGA comprises information for indicating a number of pieces of RA included in the common field of the HE-SIGB. Referring to <FIG> is a simple schematic diagram of a preferred structure of the HE-SIGA.

After receiving the RA quantity indication information in the HE-SIGA, a receive end may obtain lengths of the common fields of the SIGB-<NUM> and SIGB-<NUM> according to the RA quantity indication information, and further, correctly decode the common fields of the SIGB-<NUM> and SIGB-<NUM>.

With the information about the number of pieces of RA, an indication of a current transmission mode may be not included. In other words, the information about the number of pieces of RA may be used to indicate the current transmission mode. In other words, when a number of pieces of RA included in the HE-SIGA is zero, it indicates that the current transmission mode is a non-OFDMA transmission mode, that is, Full bandwidth MU-MIMO or single-user transmission. When the number of pieces of RA is greater than zero, and for example, is one or two, it indicates that the current transmission mode is an OFDMA transmission mode.

Referring to <FIG> is a simple schematic diagram of a structure of the HE-SIGA/B indicated in Preferred Embodiment <NUM>.

Referring to <FIG> is a simple schematic diagram of another structure of the HE-SIGA/B indicated in Preferred Embodiment <NUM>. Compared with a case in <FIG>, it is obviously seen that signaling is reduced. In addition, because full <NUM> is divided into two resource units with a size of <NUM> (<NUM>), mode indication information in the HE-SIGA is OFDMA, that is, the common fields of the SIGB-<NUM> and the SIGB-<NUM> need to include RA-<NUM>/<NUM> and RA-<NUM>/<NUM> according to a normal structure. The solution in <FIG> indicates that the number of pieces of RA included in the SIGB is one, the SIGB-<NUM> only comprises RA-<NUM>, and the SIGB-<NUM> only comprises RA-<NUM>. Therefore, the receive end may obtain allocation information of the current bandwidth.

Referring to <FIG> is another structure of the HE-SIGA/B indicated in Preferred Embodiment <NUM>. A resource unit(s) allocation situation in this embodiment is consistent with a resource unit(s) allocation situation indicated in the foregoing <FIG>.

Preferably, the indication of "the number of pieces of RA included in the common field of the HE-SIGB" may occupy different quantities of bits at different bandwidths.

For example, when a current transmission bandwidth is <NUM> or <NUM>, the indication occupies one bit. Because the SIGB-<NUM> and the SIGB-<NUM> include only one piece of RA at most, the number of pieces of RA included in the common field falls into only two cases: zero and one.

For example, when a current transmission bandwidth is <NUM>, the indication occupies two bits. Because the SIGB-<NUM> and the SIGB-<NUM> may include two pieces of RA at most, the number of pieces of RA included in the common field may fall into three cases: zero, one, and two.

For example, when a current transmission bandwidth is <NUM>, the indication occupies three bits. Because the SIGB-<NUM> and the SIGB-<NUM> may include four pieces of RA at most, the number of pieces of RA included in the common field may fall into five cases: zero, one, two, three, and four.

For another example, when a transmission bandwidth is <NUM>, two bits are used to indicate the number of pieces of RA included in the SIGB-<NUM>, and the number of pieces of RA may fall into four cases: zero, one, two, and three.

For another example, when a transmission bandwidth is <NUM>, three bits are used to indicate the number of pieces of RA included in the SIGB-<NUM>, and the number of pieces of RA may fall into eight cases: zero, one, two, three, four, five, six, and seven.

More specifically, refer to <FIG> for the case in which the common field of the HE-SIGB comprises only two pieces of RA at <NUM>.

Another possible structure is shown in <FIG>.

Preferred Embodiment <NUM> may be combined with either of Preferred Embodiment <NUM> and Preferred Embodiment <NUM>. For example, if the number of pieces of RA indicated in Preferred Embodiment <NUM> is zero, reuse of the "#sym HE-SIGB" field in the SIGA in Preferred Embodiment <NUM> may be adopted to indicate a number of scheduled users included in the user specific field of the HE-SIGB. For another example, if the number of pieces of RA indicated in Preferred Embodiment <NUM> is two, RA-<NUM> may be made a special resource allocation mode according to a specific scheduling situation, so that the dedicated user field of the HE-SIGB has least overheads.

Specially and alternatively, for Preferred Embodiment <NUM>, the quantities of pieces of RA included in the SIGB-<NUM> and the SIGB-<NUM> may be separately indicated in the HE-SIGA, as shown in <FIG>. In this case, the SIGB-<NUM> and the SIGB-<NUM> may be different in length because the quantities of pieces of RA included may be different.

Specially and alternatively, for Preferred Embodiment <NUM>, the number of pieces of RA included in the SIGB-<NUM> or the SIGB-<NUM> is indicated in the HE-SIGA, as shown in <FIG>. If the number of pieces of RA included in the SIGB-<NUM> is indicated, the number of pieces of RA included in the SIGB-<NUM> equals a total quantity of pieces of RA at a current transmission bandwidth subtracted by the number of pieces of RA included in the SIGB-<NUM>. In this case, the SIGB-<NUM> and the SIGB-<NUM> may be different in length because the quantities of pieces of RA included may be different.

The foregoing embodiments reduce signaling overheads in the SIGB to some extent.

In this preferred embodiment, referring to <FIG>, the HE-SIGB comprises information used for indicating a <NUM> whose resource allocation information and user scheduling information are currently indicated in SIGB-<NUM>. The foregoing indication may use a bitmap bitmap manner. Each bit corresponds to one <NUM> in a current transmission bandwidth, and each bit is used to indicate whether user scheduling information of the corresponding <NUM> is included in a current SIGB.

Preferably, referring to <FIG>, with reference to the indication in the HE-SIGA in Preferred Embodiment <NUM>, <FIG> is an example of applying Preferred Embodiment <NUM>. It may be seen that, in the example in <FIG>, the common fields of the SIGB-<NUM> and SIGB-<NUM> separately include a <NUM>-bit bitmap indication. Because there are four <NUM> in <NUM>, and each bit corresponds to one <NUM>, the bit is used to indicate whether user scheduling information of the corresponding <NUM> is included in the current SIGB. For example, when an indication of the bit in the bitmap is <NUM>, it indicates that user scheduling information of the <NUM> corresponding to the bit is included in the current SIGB; when the indication of the bit in the bitmap is <NUM>, it indicates that the user scheduling information of the <NUM> corresponding to the bit is not included in the current SIGB. Certainly, this also works when meanings of values <NUM> and <NUM> are reversed.

It may also be seen that, by using the method in Preferred Embodiment <NUM>, the SIGB-<NUM> and the SIGB-<NUM> may no longer use the following manner: User scheduling information of odd-numbered <NUM> is in the SIGB-<NUM>, and user scheduling information of even-numbered <NUM> is in the SIGB-<NUM>.

Certainly, preferably, the user scheduling information of the odd-numbered <NUM> may be included in the SIGB-<NUM> and the user scheduling information of the even-numbered <NUM> may be included in the SIGB-<NUM>. In this case, a bitmap in the common field of the HE-SIGB may have relatively few bits. For example, in an <NUM> case, the SIGB-<NUM> comprises two RA indications (RA at the first <NUM> and the third <NUM>) at most. Therefore, a <NUM>-bit bitmap is sufficient, and the two bits respectively represent the first and the third <NUM> in the SIGB-<NUM>, and respectively represent the second and the fourth <NUM> in the SIGB-<NUM>.

For <NUM> transmission, because there are eight <NUM>, the bitmap has eight bits, and each bit corresponds to one <NUM>. If it is still ensured that the SIGB-<NUM> comprises indication information of the odd-numbered <NUM> and the SIGB-<NUM> comprises indication information of the even-numbered <NUM>, only a <NUM>-bit bitmap is required for the <NUM>. It may be seen that, a length of the bitmap depends on a bandwidth indication in the HE-SIG-A.

A receive end receives an indication of the bitmap, as shown in <FIG>. If "<NUM>" is read from the SIGB-<NUM>, it indicates that user scheduling information of the first and the second <NUM> channels is transmitted in the SIGB-<NUM>; if "<NUM>" is read from the SIGB-<NUM>, it indicates that user scheduling information of the third and the fourth <NUM> channels is transmitted in the SIGB-<NUM>.

In Preferred Embodiment <NUM>, the HE-SIGA comprises SIGB mode indication information. The SIGB mode indication information is used to indicate an indication information type included in the HE-SIGB or is used to indicate an indication information combination in the common field of the HE-SIGB. The indication information type included in the HE-SIGB has the following example: The common field of the HE-SIGB comprises a resource allocation mode indication, or an indication of a number of scheduled users and a resource allocation mode indication, or two indications of quantities of scheduled users, or two resource allocation mode indications, or the like.

The SIGB mode indication information in Preferred Embodiment <NUM> may be included in a new field in the HE-SIGA, and may also be implicitly carried by using a polarity of the repeated L-SIG, or phase rotation of the HE-SIGA, or another manner.

As shown in <FIG> is a simple schematic diagram of a structure of the HE-SIGA/B indicated in Preferred Embodiment <NUM>.

Specifically, it is assumed that an indication of a number of users (user number) requires x1 bits, and an indication of a number of pieces of RA requires x2 bits. Therefore, the common field of the HE-SIGB has y possible different combination lengths, and an overhead of the foregoing SIGB mode indication is ceil(log2 (y)).

For a <NUM> bandwidth, y equals <NUM> (a common field length equals <NUM>, or the common field length equals x2) or y equals <NUM> (the common field length equals x1, or the common field length equals x2). Herein, the common field length equals <NUM>, and this considers reference to the technology in Preferred Embodiment <NUM>, and arranges an indication of the number of users in the "#sym HE-SIGB" field in the SIGA.

When y equals <NUM>, the SIGB mode indication occupies one bit. When the mode indication is a first value, the common field length equals <NUM> or x1, indicating that the current <NUM> is used as a large resource unit in whole and is allocated to a group of users for MU-MIMO/SU transmission. When the mode indication is a second value, the common field length equals x2, indicating that the current <NUM> is divided into multiple small resource units.

For a <NUM> bandwidth, y equals <NUM> (a common field length equals <NUM>, or the common field length equals x2) or y equals <NUM> (the common field length equals x1, or the common field length equals x2). Herein, the common field length equals <NUM>, and this considers reference to the technology in Preferred Embodiment <NUM>, and arranges an indication of the number of users in the "#sym HE-SIGB" field in the SIGA. When y equals <NUM>, only one bit is required for the mode indication. When the mode indication is a first value, the common field length equals <NUM> or x1, indicating that the current <NUM> is used as a large resource unit in whole and is allocated to a group of users for MU-MIMO/SU transmission. When the mode indication is a second value, another case is indicated and the corresponding common field length equals x2.

For an <NUM> bandwidth, y equals <NUM> (including following several cases: a common field length equals <NUM>, the common field length equals x2 + x2, the common field length equals x1 + x2, the common field length equals x2 + x1, or the common field length equals x1 + x1) or (the common field length equals x1, the common field length equals x2 + x2, the common field length equals x1 + x2, the common field length equals x2 + x1, or the common field length equals x1 + x1). When y equals <NUM>, three bits are required for the mode indication. When the mode indication is a first value, the common field length equals <NUM> or x1, indicating that the current <NUM> is used as a large resource unit in whole and is allocated to a group of users for MU-MIMO transmission. When the mode indication is a second value, the common field length equals x1 + x1, indicating that the current <NUM> is divided into two <NUM> resource units, and each <NUM> resource unit is allocated to a group of users for MU-MIMO/SU transmission. When the mode indication is a third value, the common field length equals x1 + x2, indicating that the first <NUM> of the current <NUM> is used as one large resource unit and is allocated to a group of users for MU-MIMO/SU transmission. When the mode indication is a fourth value, the common field length equals x2 + x1, indicating that the last <NUM> of the current <NUM> is used as one large resource unit and is allocated to a group of users for MU-MIMO/SU transmission. When the mode indication is a fifth value, another case is indicated and the corresponding common field length equals x2 + x2. For example, each <NUM> is used for MU-MIMO transmission, or partial <NUM> is used for MU-MIMO transmission and partial <NUM> is used for OFDMA transmission, or the like. A case shown in <FIG> is a case that the common field length is x1 + x2.

The foregoing several cases of the common field length that are separated by a comma in the brackets, for example, y equals <NUM> (the common field length equals <NUM>, or the common field length equals x2), indicate that the common field of the HE-SIGB has two possible different combination lengths, and one is that the common field length is <NUM>, and the other is that the common field length is x2. Other similar parts are not repeatedly described.

It should be noted that,
in Preferred Embodiment <NUM>, the HE-SIGA may include an indication about whether a current transmission mode is OFDMA or a non-OFDMA transmission mode. In this case, the mode indication in Preferred Embodiment <NUM> only needs an indication overhead of ceil(log2 (y-<NUM>)) bits.

Correspondingly, another embodiment provides an apparatus for processing a wireless local area network packet structure (not shown), and the apparatus is applied to a wireless local area network that uses the OFDMA technology, comprises a processing unit, and is configured to execute the methods of the foregoing embodiments. For a structure and content of a specific frame, refer to the foregoing embodiments and details are not described herein. The processing unit may be a general purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or another programmable logic device, a discrete gate or a transistor logic device, or a discrete hardware component, and may implement or execute various methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general purpose processor may be a microprocessor, any conventional processor, or the like. The steps of the method disclosed with reference to the embodiments of the present invention may be directly performed by a hardware processor, or may be performed by using a combination of hardware in the processor and a software module. It may be easily understood that, the foregoing processing apparatus of an HE-LTF may be located in an access point or a station.

<FIG> is a block diagram of an access point according to another embodiment of the present invention. The access point in <FIG> comprises an interface <NUM>, a processing unit <NUM>, and a memory <NUM>. The processing unit <NUM> controls an operation of the access point <NUM>. The memory <NUM> may include a read-only memory and a random access memory, and provides an instruction and data for the processing unit <NUM>. A part of the memory <NUM> may further include a nonvolatile random access memory (NVRAM). All components of the access point <NUM> are coupled together by using a bus system <NUM>, and in addition to a data bus, the bus system <NUM> further comprises a power bus, a control bus, and a status signal bus. However, for clarity of description, various buses are marked as the bus system <NUM> in <FIG>.

The methods for sending the foregoing various frames disclosed in the foregoing embodiments of the present invention may be applied to the processing unit <NUM>, or implemented by the processing unit <NUM>. In an implementation process, each step of the foregoing methods may be completed by means of an integrated logic circuit of hardware in the processing unit <NUM> or an instruction in a software form. The processing unit <NUM> may be a general purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or another programmable logic device, a discrete gate or a transistor logic device, or a discrete hardware component, and may implement or execute various methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general purpose processor may be a microprocessor, any conventional processor, or the like. The steps of the method disclosed with reference to the embodiments of the present invention may be directly performed by a hardware processor, or may be performed by using a combination of hardware in the processor and a software module. The software module may be located in a mature storage medium in the field, such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically-erasable programmable memory, or a register. The storage medium is located in the memory <NUM>. The processing unit <NUM> reads information in the memory <NUM>, and completes the steps of the foregoing methods with reference to the hardware of the processing unit <NUM>.

<FIG> is a block diagram of a station according to another embodiment of the present invention. The station comprises an interface <NUM>, a processing unit <NUM>, and a memory <NUM>. The processing unit <NUM> controls an operation of the station <NUM>. The memory <NUM> may include a read-only memory and a random access memory, and provides an instruction and data for the processing unit <NUM>. A part of the memory <NUM> may further include a nonvolatile random access memory (NVRAM). All components of the station <NUM> are coupled together by using a bus system <NUM>, and in addition to a data bus, the bus system <NUM> further comprises a power bus, a control bus, and a status signal bus. However, for clarity of description, various buses are marked as the bus system <NUM> in <FIG>.

The methods for receiving the foregoing various frames disclosed in the foregoing embodiments of the present invention may be applied to the processing unit <NUM>, or implemented by the processing unit <NUM>. In an implementation process, each step of the foregoing methods may be completed by means of an integrated logic circuit of hardware in the processing unit <NUM> or an instruction in a software form. The processing unit <NUM> may be a general purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or another programmable logic device, a discrete gate or a transistor logic device, or a discrete hardware component, and may implement or execute various methods, steps, and logic block diagrams disclosed in this embodiment of the present invention. The general purpose processor may be a microprocessor, any conventional processor, or the like. The steps of the method disclosed with reference to the embodiments of the present invention may be directly performed by a hardware processor, or may be performed by using a combination of hardware in the processor and a software module. The software module may be located in a mature storage medium in the field, such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically-erasable programmable memory, or a register. The storage medium is located in the memory <NUM>. The processing unit <NUM> reads information in the memory <NUM>, and completes the steps of the foregoing methods with reference to the hardware of the processing unit <NUM>.

Specifically, the memory <NUM> stores received information that enables the processing unit <NUM> to execute the methods mentioned in the foregoing embodiments.

It should be understood that "an embodiment" or "an embodiment" mentioned in the whole specification does not mean that particular features, structures, or characteristics related to the embodiment are included in at least one embodiment of the present invention. Therefore, "in an embodiment" or "in an embodiment" appearing throughout the specification does not refer to a same embodiment. In addition, these particular features, structures, or characteristics may be combined in one or more embodiments by using any appropriate manner. Sequence numbers of the foregoing processes do not mean execution sequences in various embodiments of the present invention. The execution sequences of the processes should be determined according to functions and internal logic of the processes, and should not be construed as any limitation on the implementation processes of the embodiments of the present invention.

In addition, the terms "system" and "network" may be used interchangeably in this specification. The term "and/or" in this specification describes only an association relationship for describing associated objects and represents that three relationships may exist.

It should be understood that in the embodiments of the present invention, "B corresponding to A" indicates that B is associated with A, and B may be determined according to A. However, it should further be understood that determining A according to B does not mean that B is determined according to A only; that is, B may also be determined according to A and/or other information.

A person of ordinary skill in the art may be aware that, in combination with the examples described in the embodiments disclosed in this specification, units and algorithm steps may be implemented by electronic hardware, computer software, or a combination thereof. To clearly describe the interchangeability between the hardware and the software, the foregoing has generally described compositions and steps of each example according to functions.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus, and method may be implemented in other manners. For example, the described apparatus embodiment is only an example. For example, the unit division is only logical function division and may be other division in actual implementation. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections may be implemented through some interfaces.

A part or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments of the present invention.

Claim 1:
A transmitting method for a multi-user transmission in a wireless local area network, comprising:
transmitting a high efficiency signal field A, HE SIG A field, and a high efficiency signal field B, HE SIG B field,
wherein the HE SIG A field comprises a transmission mode indication field and a #sym HE-SIG B field; the HE SIG B field comprises a user specific field, the user specific field comprises one or more user scheduling information subfields; wherein each of the one or more user scheduling information subfields comprising information of a scheduled station;
wherein when an OFDMA transmission mode is indicated by the transmission mode indication field, the #sym HE SIG B field indicates a number of the symbols in the HE SIG B field; when a non-OFDMA transmission mode is indicated by the transmission mode indication field, the #sym HE SIG B field indicates a number of scheduled stations;
wherein in the multi-user transmission, the non-OFDMA transmission mode is a full bandwidth MU-MIMO transmission.