WO2020226679A1

WO2020226679A1 - Multi-user resource unit allocation

Info

Publication number: WO2020226679A1
Application number: PCT/US2019/057265
Authority: WO
Inventors: Chusong Xiao; Yongjiang Yi; Tianan MA
Original assignee: Huawei Technologies Co. Ltd.
Priority date: 2019-05-03
Filing date: 2019-10-21
Publication date: 2020-11-12
Also published as: WO2020226931A1; WO2020226680A1; WO2020163849A1

Abstract

A circuit includes a transmitter and a processor. The transmitter is configured to transmit data at a plurality of subcarrier frequencies that are grouped into a plurality of resource units of predetermined duration. The processor is configured to allocate a first portion of a resource unit of the plurality of resource units to a first user, and allocate a second portion of the resource unit to a second user.

Description

MULTI-USER RESOURCE UNIT ALLOCATION

Inventors:

Chusong Xiao

Yongjiang Yi

Tianan Ma

CROSS-REFERENCE

[0001] This application claims the benefit of U.S. Provisional Patent Application Number 62/843, 158 filed on May 3, 2019, which is hereby incorporated by reference.

FIELD

[0002] The disclosure generally relates to electronic communication and to systems and methods used for electronic communication.

BACKGROUND

[0003] Electronic communication, including wireless electronic communication is widely used for a broad range of purposes. Electronic circuits, including electronic circuits formed as integrated circuits (ICs) on semiconductor substrates, may be used in electronic communication systems. For example, mobile phones, laptops, tablets and other user devices may use wireless electronic communication to access a wireless network. In a wireless communication network, user devices (user equipment) may wirelessly connect to an access point or base station, which is connected to a network (e.g. the Internet) and provides network access to user devices. BRIEF SUMMARY

[0004] According to one aspect of the present disclosure, there is provided a circuit that includes a transmitter configured to transmit data at a plurality of subcarrier frequencies. The plurality of subcarrier frequencies may be grouped into a plurality of resource units of having a duration. The circuit includes a processor connected to the transmitter. The processor may be configured to allocate a first portion of a resource unit of the plurality of resource units to a first user and a second portion of the resource unit to a second user.

[0005] Optionally, in any of the preceding aspects, the duration corresponds to an integer number of symbols, the processor configured to assign a first plurality of symbols of the resource unit to user data of the first user and assign a second plurality of symbols of the resource unit to user data of the second user.

[0006] Optionally, in any of the preceding aspects, the processor is further configured to add padding data to the user data of the first user to fill the first plurality of symbols of the resource unit.

[0007] Optionally, in any of the preceding aspects, the transmitter is configured to transmit a control frame that contains resource unit allocation information for all resource units of a packet to be sent after the control frame.

[0008] Optionally, in any of the preceding aspects, the resource unit allocation information in the control frame includes a first indicator of the starting symbol of the first plurality of symbols and a second indicator of the starting symbol of the second plurality of symbols.

[0009] Optionally, in any of the preceding aspects, the control frame includes a number of users sharing a resource unit for every resource unit of the packet.

[0010] Optionally, in any of the preceding aspects, the number is a four-bit number representing up to sixteen users per resource unit for every resource unit of the packet.

[0011] Optionally, in any of the preceding aspects, the control frame includes an indicator of a starting symbol for each user sharing a resource unit. [0012] Optionally, in any of the preceding aspects, the first portion is first in time, the first user is a high priority user, the second portion is second in time, and the second user is a low priority user.

[0013] Optionally, in any of the preceding aspects, the second portion coincides with a predicted interference and the second user is a low priority user.

[0014] According to still one other aspect of the present disclosure, there is provided a method that includes grouping a plurality of subcarrier frequencies into a plurality of resource units of predetermined duration and allocating the plurality of resource units to a plurality of users such that an earlier period of an individual resource unit is allocated to a first user and a later period of the individual resource unit is allocated to a second user. The method further includes sending data of the first user in the individual resource unit and subsequently sending data of the second user in the individual resource unit.

[0015] Optionally, in any of the preceding aspects, the predetermined duration extends over sixteen symbols, a first plurality of symbols of a resource unit allocated to the first user and a second plurality of symbols of the resource unit allocated to the second user.

[0016] Optionally, in any of the preceding aspects, the method further includes prior to sending data of the first user, sending a control frame that contains resource unit allocation information for the plurality of resource units including the individual resource unit.

[0017] Optionally, in any of the preceding aspects, the resource unit allocation information includes, for each of the plurality of resource units, a number of users sharing the individual resource unit and starting locations for data of each user.

[0018] Optionally, in any of the preceding aspects, the resource unit allocation information including the number of users sharing the resource unit and starting locations for data of each user are sent in an extended SIGB field of the control frame.

[0019] Optionally, in any of the preceding aspects, allocating the plurality of resource units to a plurality of users includes allocating an earlier portion of a resource unit to higher priority data and allocating a later portion of the resource unit to lower priority data.

[0020] Optionally, in any of the preceding aspects, allocating the plurality of resource units to a plurality of users includes allocating data of a low priority user or padding data to coincide with predicted interference.

[0021] According to still one other aspect of the present disclosure, there is provided a system including a transmitter configured to transmit data at a plurality of subcarrier frequencies to a plurality of users, the plurality of subcarrier frequencies grouped into a plurality of resource units of predetermined duration. The system includes a processor connected to the transmitter. The processor is configured to divide a resource unit of the plurality of resource units into a plurality of portions, each portion having an integer number of symbols. The processor is configured to allocate a first plurality of symbols of the resource unit to a first user, allocate a second plurality of symbols of the resource unit to a second user.

[0022] Optionally, in any of the preceding aspects, the system forms an Access Point (AP) providing network access to a plurality of users in a Wireless Local Area Network (WLAN).

[0023] Optionally, in any of the preceding aspects, the system may be further configured to send control frames with resource unit allocation information including, for each resource unit of a package, a number of users sharing the resource unit and a starting symbol for each user sharing the resource unit.

[0024] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the Background. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Aspects of the present disclosure are illustrated by way of example and are not limited by the accompanying figures (FIGS.) for which like references indicate elements.

[0026] FIGURE (FIG.) 1 illustrates an exemplary wireless network for communicating data.

[0027] FIG. 2 illustrates exemplary details of an instance of user equipment (UE) introduced in FIG. 1.

[0028] FIG. 3 illustrates exemplary details of an instance of an Access Point (AP) introduced in FIG. 1.

[0029] FIG. 4 illustrates an example of subcarriers assigned to different users.

[0030] FIG. 5 illustrates an example of different ways of allocating subcarriers for multiple users.

[0031] FIG. 6 illustrates examples of resource units of fixed duration.

[0032] FIG. 7 illustrates examples of resource units that are divided by time between two or more users.

[0033] FIG. 8 illustrates an example of a SIGB field of a control frame including a common field and user fields.

[0034] FIGs 9A-C illustrate examples of entries in a common field.

[0035] FIGs 10A-C illustrate examples of entries in a user field.

[0036] FIG. 11 illustrates an example of a method that includes allocating portions of a resource to different users. DETAILED DESCRIPTION

[0037] The present disclosure will now be described with reference to the figures, which in general relate to systems and methods of resource allocation that may be used in various communication systems, e.g. in wireless communication networks such as Wi-Fi networks, cellular telephone networks, or other wireless communication networks.

[0038] In some examples, a frequency spectrum that is available for wireless communication includes multiple subcarriers (subcarrier frequencies, subchannels, or tones) that may be used to convey data in parallel or concurrently. These subcarriers may be grouped into resource units of equal length, with different resource units assigned to different users. In this way, wireless communication with multiple users may be performed concurrently. Different resource units may include different numbers of subcarriers (different bandwidth) to accommodate different user needs (e.g. some users may require more data than others). For example, the IEEE 802.1 1 ax standard includes resource units that can be configured to have different numbers of subcarriers according to user requirements. Such resource units generally have a fixed duration (e.g. a predetermined time duration and predetermined number of symbols).

[0039] While resource units of configurable bandwidth provide an efficient way to serve multiple users with different requirements, some inefficiencies occur. For example, some users may not use the entire resource unit allocated to them (e.g. because resource units may be available in discrete sizes and may not be exactly sized according to user needs, or because of changing user needs, or other reasons). In this case, a portion of a resource unit may be padded (i.e. filled with padding data). In some cases, padding in this way may represent a significant unused resource.

[0040] In some examples described below, a resource unit may be divided into two or more portions by time and the portions may be allocated to two or more users according to their requirements. In this way, rather than padding a remaining portion of a resource unit when a user does not require the entire resource unit, the remaining portion of the resource unit may be allocated to another user. For example, where a resource unit includes sixteen symbols, the first n symbols may be allocated to a first user and the following 16-n symbols may be allocated to a second user. Or the 16-n symbols may be split between two or more additional users. Up to sixteen users may share such a resource unit (e.g. each user may be allocated as little as a single symbol).

[0041] A packet may utilize multiple resource units, with one or more of the resource units shared (divided by time) between two or more users. A control frame may be sent prior to the packet with allocation information including, for each resource unit of the packet, the number of users sharing the resource unit and starting locations (starting symbols) for each user within the packet.

[0042] It is understood that the present embodiments of the disclosure may be implemented in many different forms and that claims scopes should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the inventive embodiment concepts to those skilled in the art. Indeed, the disclosure is intended to cover alternatives, modifications and equivalents of these embodiments, which are included within the scope and spirit of the disclosure as defined by the appended claims. Furthermore, in the following detailed description of the present embodiments of the disclosure, numerous specific details are set forth in order to provide a thorough understanding. However, it will be clear to those of ordinary skill in the art that the present embodiments of the disclosure may be practiced without such specific details.

[0043] FIG. 1 illustrates a wireless network for communicating data. The communication system 100 includes, for example, user equipment 1 10A-1 10C, radio access networks (RANs) 120A-120B, a core network 130, a public switched telephone network (PSTN) 140, the Internet 150, and other networks 160. Additional or alternative networks include private and public data-packet networks including corporate intranets. While certain numbers of these components or elements are shown in the figure, any number of these components or elements may be included in the system 100.

[0044] In one embodiment, the RANs 120A-120B may include access points (APs) 170 configured to form one or more Wireless Local Area Networks (WLANs). For example, APs 170A-170B (APs 170) may use technology such as defined by IEEE 802.1 1 n or 802.1 1 ax to provide wireless network access to one or more devices (e.g. User Equipment 1 10A) in a home, workplace, airport, or other location. APs 170 may employ orthogonal frequency-division multiplexing (OFDM) to communicate with User Equipment 1 10A-1 10C.

[0045] In one embodiment, the RANs 120A-120B may include millimeter and/or microwave access points (e.g. APs 170). The APs may include, but are not limited to, a connection point (an mmW CP) capable of mmW communication (e.g., a mmW base station). The mmW APs may transmit and receive signals in a frequency range, for example, from 24 GHz to 100 GHz, but are not required to operate throughout this range.

[0046] In one embodiment, the wireless network may be a fifth generation (5G) network including at least one 5G base station which employs orthogonal frequency- division multiplexing (OFDM) and/or non-OFDM and a transmission time interval (TTI) shorter than 1 ms (e.g. 100 or 200 microseconds), to communicate with the communication devices. In general, a base station may also be used to refer any of the eNB and the 5G BS (gNB). In addition, the network may further include a network server for processing information received from the communication devices via the at least one eNB or gNB. The term “access point” or“AP” is generally used in this application to refer to an apparatus that provides wireless communication to user equipment through a suitable wireless network, which may include a cellular network, and it will be understood that an AP may be implemented by a base station of a cellular network.

[0047] System 100 enables multiple wireless users to transmit and receive data and other content. The system 100 may implement one or more channel access methods, such as but not limited to code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or single-carrier FDMA (SC-FDMA).

[0048] The user equipment (UE) 1 10A-1 10C are configured to operate and/or communicate in the system 100. For example, the user equipment 1 10A-1 10C are configured to transmit and/or receive wireless signals or wired signals. Each user equipment 1 10A-1 10C represents any suitable end user device and may include such devices (or may be referred to) as a user equipment/device, wireless transmit/receive unit (UE), mobile station, fixed or mobile subscriber unit, pager, cellular telephone, personal digital assistant (PDA), smartphone, laptop, computer, touchpad, tablet, wireless sensor, wearable devices or consumer electronics device.

[0049] In the depicted embodiment, the RANs 120A-120B include one or more base stations or access points 170A, 170B (collectively, base stations or access points 170). Each of the access points 170 is configured to wirelessly interface with one or more of the UEs 1 10A, 1 10B, 1 10C to enable access to the core network 130, the PSTN 140, the Internet 150, and/or the other networks 160. For example, the Access Points (APs) 170 may include one or more of several well-known devices, such as a wireless router, or a server, router, switch, or other processing entity with a wired or wireless network, a base transceiver station (BTS), a Node-B (NodeB), an evolved NodeB (eNB), a next (fifth) generation (5G) NodeB (gNB), a Home NodeB, a Home eNodeB, or a site controller.

[0050] In one embodiment, the AP 170A forms part of the RAN 120A, which may include other APs, elements, and/or devices. Similarly, the AP 170B forms part of the RAN 120B, which may include other APs, elements, and/or devices. Each of the APs 170 operates to transmit and/or receive wireless signals within a particular geographic region or area (sometimes referred to as a“cell” in a cellular network). In some embodiments, multiple-input multiple-output (MIMO) technology may be employed having multiple transceivers for each area.

[0051] The APs 170 communicate with one or more of the user equipment 1 10A- 1 10C over one or more air interfaces (not shown) using wireless communication links. The air interfaces may utilize any suitable radio access technology.

[0052] It is contemplated that the system 100 may use multiple channel access functionality, including for example schemes in which the APs 170 and user equipment 1 10A-1 10C are configured to implement an IEEE 802.1 1 standard (e.g. the IEEE 802.1 1 ax standard), the Long Term Evolution wireless communication standard (LTE), LTE Advanced (LTE-A), and/or LTE Multimedia Broadcast Multicast Service (MBMS). In other embodiments, the base stations 170 and user equipment 1 10A-1 10C are configured to implement UMTS, HSPA, or HSPA+ standards and protocols. Of course, other multiple access schemes and wireless protocols may be utilized.

[0053] The RANs 120A-120B are in communication with the core network 130 to provide the user equipment 1 10A-1 10C with voice, data, application, Voice over Internet Protocol (VoIP), or other services. As appreciated, the RANs 120A-120B and/or the core network 130 may be in direct or indirect communication with one or more other RANs (not shown). The core network 130 may also serve as a gateway access for other networks (such as PSTN 140, Internet 150, and other networks 160). In addition, some or all of the user equipment 1 10A-1 10C may include functionality for communicating with different wireless networks over different wireless links using different wireless technologies and/or protocols.

[0054] Although FIG. 1 illustrates one example of a communication system, various changes may be made to FIG. 1 . For example, the communication system 100 could include any number of user equipment, access points, networks, or other components in any suitable configuration. It is also appreciated that the term user equipment may refer to any type of wireless device communicating with a radio network node in a cellular or mobile communication system. Non-limiting examples of user equipment are a target device, device-to-device (D2D) user equipment, machine type user equipment or user equipment capable of machine-to-machine (M2M) communication, laptops, PDA, iPad, Tablet, mobile terminals, smart phones, laptop embedded equipped (LEE), laptop mounted equipment (LME) and USB dongles.

[0055] FIG. 2 illustrates example details of an UE 1 10 that may implement the methods and teachings according to this disclosure. The UE 1 10 may for example be a mobile telephone but may be other devices in further examples such as a desktop computer, laptop computer, tablet, hand-held computing device, automobile computing device and/or other computing devices. As shown in the figure, the exemplary UE 1 10 is shown as including at least one transmitter 202, at least one receiver 204, memory 206, at least one processor 208, and at least one input/output device 212. The processor 208 can implement various processing operations of the UE 1 10. For example, the processor 208 can perform signal coding, data processing, power control, input/output processing, or any other functionality enabling the UE 1 10 to operate in the system 100 (FIG. 1 ). The processor 208 may include any suitable processing or computing device configured to perform one or more operations. For example, the processor 208 may include a microprocessor, microcontroller, digital signal processor, field programmable gate array, or application specific integrated circuit.

[0056] The transmitter 202 can be configured to modulate data or other content for transmission by at least one antenna 210. The transmitter 202 can also be configured to amplify, filter and to frequency convert RF signals before such signals are provided to the antenna 210 for transmission. The transmitter 202 can include any suitable structure for generating signals for wireless transmission.

[0057] The receiver 204 can be configured to demodulate data or other content received by the at least one antenna 210. The receiver 204 can also be configured to amplify, filter and frequency convert RF signals received via the antenna 210. The receiver 204 can include any suitable structure for processing signals received wirelessly. The antenna 210 can include any suitable structure for transmitting and/or receiving wireless signals. The same antenna, antenna 210, can be used for both transmitting and receiving RF signals, or alternatively, different antennas can be used for transmitting signals and receiving signals.

[0058] It is appreciated that one or multiple transmitters 202 could be used in the UE 1 10, one or multiple receivers 204 could be used in the UE 1 10, and one or multiple antennas 210 could be used in the UE 1 10. Although shown as separate blocks or components, at least one transmitter 202 and at least one receiver 204 could be combined into a transceiver. Accordingly, rather than showing a separate block for the transmitter 202 and a separate block for the receiver 204 in FIG. 2, a single block for a transceiver could have been shown.

[0059] The UE 1 10 further includes one or more input/output devices 212. The input/output devices 212 facilitate interaction with a user. Each input/output device 212 includes any suitable structure for providing information to or receiving information from a user, such as a speaker, microphone, keypad, keyboard, display, or touch screen.

[0060] In addition, the UE 1 10 includes at least one memory 206. The memory 206 stores instructions and data used, generated, or collected by the UE 1 10. For example, the memory 206 could store software or firmware instructions executed by the processor(s) 208 and data used to reduce or eliminate interference in incoming signals. Each memory 206 includes any suitable volatile and/or non-volatile storage and retrieval device(s). Any suitable type of memory may be used, such as random access memory (RAM), read only memory (ROM), hard disk, optical disc, subscriber identity module (SIM) card, memory stick, secure digital (SD) memory card, and the like.

[0061] FIG. 3 illustrates an example AP 170 that may implement the methods and teachings according to this disclosure. As shown in the figure, the AP 170 includes at least one processor 308, at least one transmitter 302, at least one receiver 304, one or more antennas 310, and at least one memory 306. The processor 308 implements various processing operations of the AP 170, such as signal coding, data processing, power control, input/output processing, or any other functionality. Each processor 308 includes any suitable processing or computing device configured to perform one or more operations. Each processor 308 could, for example, include a microprocessor, microcontroller, digital signal processor, field programmable gate array, or application specific integrated circuit.

[0062] Each transmitter 302 includes any suitable structure for generating signals for wireless transmission to one or more UEs 1 10 or other devices. Each receiver 304 includes any suitable structure for processing signals received wirelessly from one or more UEs 1 10 or other devices. Although shown as separate blocks or components, at least one transmitter 302 and at least one receiver 304 may be combined into a transceiver. Each antenna 310 includes any suitable structure for transmitting and/or receiving wireless signals. While a common antenna 310 is shown here as being coupled to both the transmitter 302 and the receiver 304, one or more antennas 310 could be coupled to the transmitter(s) 302, and one or more separate antennas 310 could be coupled to the receiver(s) 304. Each memory 306 includes any suitable volatile and/or non-volatile storage and retrieval device(s).

[0063] The technology described herein can be implemented using hardware, software, or a combination of both hardware and software. The software used is stored on one or more of the processor readable storage devices described above to program one or more of the processors to perform the functions described herein. The processor readable storage devices can include computer readable media such as volatile and non-volatile media, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer readable storage media and communication media. Computer readable storage media may be implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Examples of computer readable storage media include RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a computer. A computer readable medium or media does (do) not include propagated, modulated or transitory signals.

[0064] Communication media typically embodies computer readable instructions, data structures, program modules or other data in a propagated, modulated or transitory data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term“modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as RF and other wireless media. Combinations of any of the above are also included within the scope of computer readable media.

[0065] In alternative embodiments, some or all of the software can be replaced by dedicated hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs), Application-specific Integrated Circuits (ASICs), Application- specific Standard Products (ASSPs), System-on-a-chip systems (SOCs), Complex Programmable Logic Devices (CPLDs), special purpose computers, etc. In one embodiment, software (stored on a storage device) implementing one or more embodiments is used to program one or more processors. The one or more processors can be in communication with one or more computer readable media/ storage devices, peripherals and/or communication interfaces. [0066] Figure 4 shows an example of how a plurality of subcarriers (discrete subcarrier frequencies or tones) of a portion of a frequency spectrum may be used by a transmitter (e.g. transmitter 302 of AP 170) and corresponding receiver (e.g. receiver 204 of UE 1 10). Subcarriers may be spaced apart along the frequency spectrum at fixed intervals and adjacent subcarriers may be allocated to a particular user. For example, Figure 4 shows a first group of subcarriers allocated to user 1 (e.g. allocated for communication with a first UE) and a second group of subcarriers allocated to user 2 (e.g. allocated for communication with a second UE concurrently with communication with the first UE). A pilot subcarrier 400 is also shown between subcarrier groups of user 1 and user 2. In addition to the data subcarriers of user 1 and user 2, and pilot subcarrier 400, guard bands may be provided (unused subcarriers) to reduce interference. While the example of Figure 4 shows eight subcarriers assigned to user 1 and eight subcarriers assigned to user 2, in some cases larger number of subcarriers may be allocated to a user and the numbers of subcarriers may be different for different users depending on their requirements.

[0067] Figure 5 shows examples of allocation of a 20 MFIZ portion of frequency spectrum. This may be allocated to a single user that uses 242 subcarriers concurrently for communication. Alternatively, two groups of subcarriers may be allocated to two users, with 106 subcarriers in each group so that, for example, an AP may communicate with two UEs concurrently. Some of the 242 subcarriers used in the single-user case are unused in this configuration to provide guard bands. In another alternative, four groups of subcarriers may be allocated to four users, with 52 subcarriers in each group so that, for example, an AP may communicate with four UEs concurrently. In another alternative, eight groups of subcarriers may be allocated to eight users, with 26 subcarriers in each group so that, for example, an AP may communicate with eight UEs concurrently. It will be understood that the frequency allocation examples of Figure 5 are for illustration and that other frequency allocation options may be implemented based on grouping subcarriers differently. This may include allocating different numbers of subcarriers to different users (dividing available subcarriers unequally). For example, a first group may include 106 subcarriers assigned to a first user, a second group may include 52 subcarriers assigned to a second user, and third and fourth groups may each include 26 subcarriers assigned to third and fourth users respectively. In this way, different users may be assigned different numbers of subchannels according to their requirements.

[0068] Figure 6 illustrates an example of allocation of communication resources showing both frequency and time, including different bandwidth allocated for different users. In the example shown, the time axis shows packet 1 , packet 2, and packet 3 of equal duration, which may be a fixed time period (e.g. fixed number of clock cycles). Within each packet, frequency (i.e. subcarriers, as illustrated in Figures 4 and 5) may be allocated to one or more users in one or more Resource Units (RUs). In this example, an RU is a unit of allocating frequency to a user for a fixed duration. For example, in packet 1 , the entire frequency spectrum illustrated is allocated as a single resource unit 502. Resource Unit 502 is allocated to user 1 . In packet 2, the subcarriers are divided, or grouped, to form resource unit 504, which is allocated to user 1 and resource unit 506, which is allocated to user 2. In packet 3, the subcarriers are divided, or grouped, to form resource unit 508, which is allocated to user 1 , resource unit 510, which is allocated to user 2, and resource unit 512, which is allocated to user 3. Thus, different grouping (including unequal groupings) of subcarriers into RUs at different times may accommodate changing user requirements. Allocation of subcarriers to RUs may be performed on a packet by packet basis and allocation information may be sent in control frames between packets (not shown in Figure 6).

[0069] In some cases, the capacity of one or more resource units may not be fully utilized. For example, allocation of subcarriers (frequency allocation) may be limited to discrete amounts (e.g. numbers of subcarriers illustrated in Figure 5) so that the number of subcarriers selected for a resource unit may be more than needed (e.g. where 30 subcarriers might be sufficient, a resource unit of 52 subcarriers may be allocated because the next biggest resource unit has 26 subcarriers, which may be insufficient). This extra capacity may result in some padding data being added to one or more resource units. For example, Figure 6 shows padding data 514 (shaded) in resource unit 508, padding data 516 in resource unit 510, and padding data 518 in resource unit 512 (padding data is not shown in resource units 502, 504, 506 but may also be included in these or any other resource units). Unused capacity in resource units and inclusion of padding data may be inefficient and, in some cases, may have significant impact. [0070] Figure 7 shows an example, according to the present technology, that includes dividing a resource unit into a plurality of portions by time so that the resource unit can be more efficiently utilized, for example, by allocating a first portion to a first user and a second portion to a second user when appropriate (e.g. the first user does not need the entire resource unit). For example, a processor, such as processor 308 of AP 170 may implement allocation as shown in Figure 7 and may apply it to transmission by transmitter 302.

[0071] Figure 7 shows packet 720 that includes 16 symbols (i.e. fixed duration, with each RU of packet 720 having an equal number of symbols and extending the same amount of time). In an example, each symbol may be an OFDMA symbol of 12.8 microseconds duration. A guard interval may be provided between symbols (e.g. 0.8, 1 .6, or 3.2 microseconds). As can be seen in Figure 7, each RU is divided by time between multiple users. RUs are divided by symbol so that a first number of symbols are allocated to a first user, a second number of symbols are allocated to a second user, and so on. In this way, an RU may be allocated to a single user, two users, or up to sixteen users (corresponding to sixteen symbols). Rather than using a RU as a unit of allocation to users as in Figure 6, here each symbol of an RU may be separately allocated and may be considered a unit of allocation to users. For example, Figure 7 shows symbols 0 to 7 of RU 26 (an RU with 26 subcarriers) allocated to user 0, symbols 8 to 1 1 allocated to user 1 , and symbols 12 to 15 allocated to user 2. While this arrangement may not use the entire capacity of each RU so that some padding data may be used, the amount of padding data is generally reduced, and efficiency is generally increased. In many cases, padding data occupies less than a symbol within an RU (e.g. padding data 722, which occupies a portion of symbol 15 in RU 26). In some cases, padding data may occupy more than a symbol within an RU (e.g. padding data 724). Allocation of portions of RUs by time may be applied to RUs of any size and Figure 7 shows RU 52 (an RU with 52 subcarriers) having symbols 0 to 9 allocated to user 3 and symbols 10 to 15 allocated to user 4. Figure 7 also shows RU 106 (an RU with 106 subcarriers) having symbols 0 to 1 1 allocated to user 5 and symbols 12 to 15 allocated to user 6, with symbol 15 of RU 106 filled with padding data 726.

[0072] In some cases, allocation of symbols of an RU to users may be on a priority basis. For example, earlier symbols of an RU may be allocated to higher priority users and later symbols of an RU may be allocated to lower priority users. Thus, for example, in RU 26, user 0 may be a high priority user and user 2 may be a low priority user (and user 1 may be an intermediate priority user). Any number of different priority levels may be used to determine the order in which different users are assigned within an RU.

[0073] In some cases, some pattern of interference may occur and may be known at the time of allocation. Such patterns may be used when allocating users to different periods in an RU. For example, a periodic pattern of interference may allow some prediction of when interference is likely to occur during a packet (e.g. which symbols are more likely to be affected). If interference is expected earlier in an RU, then lower priority data may be sent first and higher priority data may be sent later (when interference is expected to be less). If interference is expected later in an RU, then higher priority data may be sent first and lower priority data may be sent later. In some cases, allocation may ensure that padding data coincides with a period when interference is expected. For example, padding data 724 may be timed to coincide with symbol 15 because interference is expected during symbol 15.

[0074] In general, allocation information for a packet is transmitted before the packet so that a receiver can accurately map received data to different users. For example, processor 308 may be configured to generate allocation information and transmitter 302 of AP 170 may be configured to send allocation information regarding a packet prior to sending the packet so that when a receiver such as receiver 204 of UE 1 10 receives the packet, processor 208 can correctly map the data of different URs of the packet to different users. A control frame or preamble containing allocation information may be sent before a packet (e.g. between packets, a control frame for the next packet may be sent, or a preamble may precede user data in a packet). In one example, allocation information, including allocation of different symbols of an RU to different users, may be transmitted by adapting or extending structures of a wireless communication protocol. For example, IEEE 802.1 1 ax includes an optional FIE-SIG-B field of variable length that may be included in a preamble of a frame or packet (e.g. packet 720) to provide information regarding multiple users and the RUs assigned to them. Such a structure may be adapted to convey information regarding allocation of symbols within an RU. [0075] Figure 8 shows an example of how the HE-SIG-B (SIGB 838) field may include a common field 832 and user specific field 834. Common field 832 includes common bits, Cyclic Redundancy Check (CRC) bits, and tail bits (e.g. for convolutional code). User specific field 834 includes separate user specific fields for each RU (e.g. user specific fields 836, 838, 840) that may include a Modulation and Coding Scheme (MCS) for the RU, a number of spatial streams, and other information. The user specific field may be adapted to indicate information regarding how an RU is divided between users so that a receiver can correctly identify which data is associated with a given user. Each RU may have a separate user specific field with corresponding information for the RU.

[0076] Figure 9A gives an example of common field bits of a SIGB field adapted for the present technology (e.g. implementation of common field 832). The name of the subfield is given in the first column, the number of bits in the subfield in the second column, and a brief description in the third column. An RU Allocation subfield includes Nx60 bits (where N depends on bandwidth) and indicates the RU assignment to be used in the data portion in the frequency domain (e.g. which subcarriers are allocated to the RU). The RU Allocation subfield also indicates the number of users for each RU for either Multiuser Multiple Input Multiple Output (MU-MIMO) or shared RU in time domain (e.g. as illustrated in Figure 7). For RUs of size greater than or equal to 106 subcarriers (tones) that support MU-MIMO, the RU Allocation subfield indicates the number of users multiplexed using MU-MIMO. The bits in the RU Allocation subfield include a 6-bit ru-allocation-format subfield, an 18-bit RU sharing indication subfield, and 36 bits representing numbers of users for each RU. The RU allocation subfield may be comprised of N 60-bit subfields where the number N depends on the bandwidth that is allocated. For example, N = 1 for a 20 MFIz and a 40 MFIz FIE (High Efficiency) MU (Multiuser) PPDU (PHY Protocol Data Unit), N = 2 for an 80 MHz HE MU PPDU, N = 4 for a 160 MHz or 80+80 MHz HE MU PPDU, N = 8 for a 320 MHz or 160+160 MHz HE MU PPDU.

[0077] A Center 26-tone RU subfield consists of a single bit that is present if the bandwidth field in the HE-SIG-A field (another part of the control frame or preamble) is set to indicate a bandwidth greater than 40MHz and not present otherwise. [0078] A Cyclic Redundancy Code (CRC) subfield consists of four bits in this example. The CRC is calculated over bits 0 to L of the HE-SIG-B field (L = x for each Common field where x = N * 60 when the Center 26-tone RU field is present, and x = /V x 60 -1 otherwise, and L = 31 for an User Block field that contains one User field and L = 63 for an User Block field that contains two User fields). Refer to FIG 9A CRC field.

[0079] A Tail subfield consists of 6 bits that are used to terminate the trellis of a convolutional coder. This may be set to 0 by default.

[0080] Figure 9B illustrates an example of RU Allocation subfield bits adapted for the present technology (e.g. implementation of RU Allocation subfield of Figure 9A). The name of the subfield is given in the first column, the number of bits in the subfield in the second column, and a brief description in the third column. An ru_allocation_format subfield consists of six bits that indicate the RU allocation format as illustrated for example in Figure 9C.

[0081] An ru_mu_mimo subfield consists of 18 bits representing up to 9 RUs, with two bits for each RU (i.e. 2-bit code for each RU). Where the number of RUs is less than nine, this field may be padded to the end. Four different examples of such 2-bit codes are shown including 00 indicating the RU is empty, 01 indicating the RU is reserved, 10 indicating that users share the RU in Single User (SU) format through time division (e.g. as illustrated in Figure 7), and 1 1 indicating that users share the RU through MU-MIMO.

[0082] An ru_user_number subfield consists of thirty-six bits that indicates the number of users per RU including multiple users using MU-MIMO and using SU sharing in the time domain (e.g. as shown in Figure 7). This includes four bits for each RU (up to 9 RUs). The number of users is simply the 4-bit number +1 so that 0 corresponds to one user, 1 corresponds to two users, and so on up to 15, which corresponds to 16 users, which is the maximum number of users for an RU in this example.

[0083] Figure 9C illustrates an example of how the six bits of the ru_al location- format subfield of Figure 9B may be implemented. Up to nine RUs (#1 to #9) are allocated (e.g. 9 RUs, each of 26 subcarriers, as illustrated in the first line). It can be seen that the available bandwidth may be divided in various ways according to different user needs.

[0084] In addition to the information provided in the common field of the HE-SIG-B field (e.g. SIGB 838) illustrated in Figures 9A-C, a user specific field (e.g. user specific field 834) may be adapted to indicate information regarding how each RU is divided between multiple users so that a receiver can correctly identify which data in an RU is associated with a given user. Figure 10A illustrates an example of how bits of an individual user specific field for an RU (e.g. user specific field 836) may be formatted to convey RU allocation information.

[0085] A User subfield consists of Nx32 bits. The User field format for a non-MU- MIMO and MU-MIMO are defined by this field where N =1 for a last user specific field that has only one user and N=2 otherwise.

[0086] A CRC subfield consists of four bits which are calculated over bits 0 to 31 for a user specific field corresponding to one user and is calculated over bits 0 to 63 for a user specific field corresponding to two users.

[0087] A Tail subfield consists of six bits that are used to terminate the trellis of a convolutional decoder. It may be set to zero by default.

[0088] Figures 10B and 10C illustrate two examples of the 32 bits (bits B0 to B31 ) of the user subfield illustrated in Figure 10A. Figure 10B shows a first example that may be used in a non-MU-MIMO implementation. The first column indicates the bit or bits of a subfield, the second column indicates the subfield name, the third column indicates the number of bits in the subfield, and the fourth column provides a brief description.

[0089] Bits B0 to B10 form the STA-ID subfield, which thus consists of 1 1 bits. These bits are set to a value of the element indicated from the transmission vector (TXVECTOR) parameter STA_ID_LIST.

[0090] Bits B1 1 to B13 form the Number of Space Time Stream (NSTS) subfield, which thus consists of 3 bits. These bits represent the number of space-time streams minus 1 for up to eight streams. [0091] Bit B14 forms the Beamformed subfield, which thus consists of only one bit. This bit indicates use of beamforming. It is set to 1 if a beamforming steering matrix is applied to the waveform in an SU transmission and is set to 0 otherwise.

[0092] Bits B15 to B18 form the MCS subfield, which thus consists of four bits. These four bits represent the modulation and coding scheme as a four-bit number n, with each value of n specifying a corresponding scheme MCSn, where n = 0, 1 , 2... 1 1 for 12 schemes. Values 12 to 15 are reserved in this example.

[0093] Bit B19 forms the DCM subfield, which thus consists of only one bit. This bit indicates whether DCM (Dual Carrier Modulation) is used. It is set to 1 to indicate that the payload of the corresponding user of the HE MU PPDU is modulated with DCM for the MCS. It is set to 0 to indicate that the payload of the corresponding user of the PPDU is not modulated with DCM for the MCS. DCM is not applied in combination with STBC.

[0094] Bit 20 forms the coding subfield, which thus consists of only one bit. This bit indicates whether BCC (binary convolutional code) or LDPC (low density parity check) is used. It may be set to 0 to indicate BCC and set to 1 to indicate LDPC.

[0095] Bits B21 to B31 form the user_symbol_index, which thus consists of eleven bits. These bits identify a starting symbol for a given user within an RU (this may accommodate more than 16 symbols, e.g. in some examples, a packet may be up to 5ms in duration and can include up to 1389 symbols). These bits may be considered an addition to accommodate multiple users by time (by symbol within an RU).

[0096] Figure 10C illustrates another example of how the 32 bits of the user subfield of Figure 10A may be used in an MU-MIMO implementation. The first column indicates the bit or bits of a subfield, the second column indicates the subfield name, the third column indicates the number of bits in the subfield, and the fourth column provides a brief description. Certain subfields (e.g. STA-ID, MCS, and coding) are similar to those of Figure 10B (a non-MU-MIMO implementation) and are not described again here.

[0097] Certain subfields are different to those of Figure 10B. For example, bits B1 1 to B14 form the Spatial Configuration subfield, which thus consists of four bits. These bits identify the number of spatial streams for a station (STA) in an MU-MIMO allocation.

[0098] Bits B21 to B31 form the user_symbol_index subfield, which thus consists of eleven bits. These bits provide the starting symbol for a given user. The value of this subfield may be set to a default value for EHT (Enhanced Throughput). For example, the default value may be set to zero. It can be seen that in both the non-MU- MIMO implementation of Figure 10B and the MU-MIMO implementation of Figure 10C, a user-symbol-index subfield of 1 1 bits is sufficient to specify a starting symbol location for a given user and thus allow receiving equipment (e.g. UE 1 10) to correctly determine which data in an RU corresponds to which user.

[0099] Figure 1 1 illustrates an example of method that includes grouping a plurality of subcarrier frequencies into a plurality of resource units of predetermined duration 1 100 and allocating the plurality of resource units to a plurality of users such that an earlier period of an individual resource unit is allocated to a first user and a later period of the individual resource unit is allocated to a second user 1 102. The method further includes sending data of the first user in the individual resource unit 1 104 and subsequently sending data of the second user in the individual resource unit 1 106.

[00100] Prior to sending data of the first user (e.g. prior to step 1 100), a control frame that contains resource unit allocation information for the plurality of resource units including the individual resource unit may be sent (not shown in Figure 1 1 ). The resource unit allocation information may include, for each of the plurality of resource units, a number of users sharing the individual resource unit and starting locations for data of each user. The resource unit allocation information including the number of users sharing the resource unit and starting locations for data of each user may be sent in an extended SIGB field of the control frame. Allocating the plurality of resource units to a plurality of users may include allocating an earlier portion of a resource unit to higher priority data and allocating a later portion of the resource unit to lower priority data. Allocating the plurality of resource units to a plurality of users may include allocating data of a low priority user or padding data to coincide with predicted interference. [00101] It is understood that the present subject matter may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this subject matter will be thorough and complete and will fully convey the disclosure to those skilled in the art. Indeed, the subject matter is intended to cover alternatives, modifications and equivalents of these embodiments, which are included within the scope and spirit of the subject matter as defined by the appended claims. Furthermore, in the following detailed description of the present subject matter, numerous specific details are set forth in order to provide a thorough understanding of the present subject matter. However, it will be clear to those of ordinary skill in the art that the present subject matter may be practiced without such specific details.

[00102] Aspects of the present disclosure are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatuses (systems) and computer program products according to embodiments of the disclosure. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable instruction execution apparatus, create a mechanism for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

[00103] The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The aspects of the disclosure herein were chosen and described in order to best explain the principles of the disclosure and the practical application, and to enable others of ordinary skill in the art to understand the disclosure with various modifications as are suited to the particular use contemplated.

[00104] Although the present disclosure has been described with reference to specific features and embodiments thereof, it is evident that various modifications and combinations can be made thereto without departing from scope of the disclosure. The specification and drawings are, accordingly, to be regarded simply as an illustration of the disclosure as defined by the appended claims, and are contemplated to cover any and all modifications, variations, combinations or equivalents that fall within the scope of the present disclosure. Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

CLAIMS What is claimed is:

1 . A circuit, comprising:

a transmitter configured to transmit data at a plurality of subcarrier frequencies, the plurality of subcarrier frequencies grouped into a plurality of resource units having a duration; and

a processor connected to the transmitter, the processor configured to allocate a first portion of a resource unit of the plurality of resource units to a first user and a second portion of the resource unit to a second user.

2. The circuit of claim 1 wherein the duration corresponds to an integer number of symbols, the processor configured to assign a first plurality of symbols of the resource unit to user data of the first user and assign a second plurality of symbols of the resource unit to user data of the second user.

3. The circuit of any one of claims 1 -2 wherein the processor is further configured to add padding data to the user data of the first user to fill the first plurality of symbols of the resource unit.

4. The circuit of any one of claims 1 -3 wherein the transmitter is configured to transmit a control frame that contains resource unit allocation information for all resource units of a packet to be sent after the control frame.

5. The circuit of claim 4 wherein the resource unit allocation information in the control frame includes a first indicator of a starting symbol of the first plurality of symbols and a second indicator of a starting symbol of the second plurality of symbols.

6. The circuit of claim 4 wherein the control frame includes a number of users sharing a resource unit for every resource unit of the packet.

7. The circuit of claim 6 wherein the number of users is a four-bit number representing up to sixteen users per resource unit for every resource unit of the packet.

8. The circuit of claim 6 wherein the control frame includes an indicator of a starting symbol for each user sharing a resource unit.

9. The circuit of claim 1 wherein the first portion is first in time, the first user is a high priority user, the second portion is second in time, and the second user is a low priority user.

10. The circuit of claim 1 wherein the second portion coincides with a predicted interference and the second user is a low priority user.

1 1 . A method comprising:

grouping a plurality of subcarrier frequencies into a plurality of resource units of predetermined duration;

allocating the plurality of resource units to a plurality of users such that an earlier period of an individual resource unit is allocated to a first user and a later period of the individual resource unit is allocated to a second user;

sending data of the first user in the individual resource unit; and

subsequently sending data of the second user in the individual resource unit.

12. The method of claim 1 1 wherein the predetermined duration extends over sixteen symbols, a first plurality of symbols of a resource unit allocated to the first user and a second plurality of symbols of the resource unit allocated to the second user.

13. The method of any one of claims 1 1 -12 further comprising:

prior to sending data of the first user, sending a control frame that contains resource unit allocation information for the plurality of resource units including the individual resource unit.

14. The method of any one of claims 1 1 -13 wherein the resource unit allocation information includes, for each of the plurality of resource units, a number of users sharing the individual resource unit and starting locations for data of each user.

15. The method of claim 14 wherein the resource unit allocation information including the number of users sharing the resource unit and starting locations for data of each user are sent in an extended SIGB field of the control frame.

16. The method of any one of claims 1 1 -15 wherein allocating the plurality of resource units to a plurality of users includes allocating an earlier portion of a resource unit to higher priority data and allocating a later portion of the resource unit to lower priority data.

17. The method of any one of claims 1 1 -16 wherein allocating the plurality of resource units to a plurality of users includes allocating data of a low priority user or padding data to coincide with predicted interference.

18. A system comprising:

a transmitter configured to transmit data at a plurality of subcarrier frequencies to a plurality of users, the plurality of subcarrier frequencies grouped into a plurality of resource units of predetermined duration; and

a processor connected to the transmitter, the processor configured to divide a resource unit of the plurality of resource units into a plurality of portions, each portion having an integer number of symbols, the processor configured to allocate a first plurality of symbols of the resource unit to a first user, allocate a second plurality of symbols of the resource unit to a second user.

19. The system of claim 18 wherein the system forms an Access Point (AP) providing network access to a plurality of users in a Wireless Local Area Network (WLAN).

20. The system of any one of claims 18-19 wherein the processor is further configured to send control frames with resource unit allocation information including, for each resource unit of a package, a number of users sharing the resource unit and a starting symbol for each user sharing the resource unit.