System and Method for WLAN OFDMA Design of Subcarrier Groups and Frame Format

• US 20200136769A1
• Filed: 12/31/2019
• Published: 04/30/2020
• Est. Priority Date: 12/18/2013
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Aboul-Magd, Osama, Suh, Jung Hoon, Au, Kwok Shum
• Granted Patent: US 11,012,202 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 27/2603 Signal structure ensuring backward compatibility with legacy system
• CPC Class Codes: H04L 27/2656 Frame synchronisation, e.g. packet synchronisation, time division duplex [TDD] switching point detection or subframe synchronisation
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/1438 Negotiation of transmission parameters prior to communication modified according to link quality H04L1/0001
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 74/0816 with collision avoidance
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

Embodiments are provided for WLAN Orthogonal Frequency Division Multiple Access (OFDMA) design of subcarrier groups and corresponding frame format. An embodiment method includes grouping a plurality of subcarriers for OFDMA transmissions into a plurality of subcarrier groups in accordance with a pre-defined grouping structure for subcarriers. The method further includes allocating the subcarrier groups to a plurality of corresponding users, and signaling, to the users, a map of the subcarrier groups to the corresponding users. According to the pre-defined grouping structure, each one of the subcarrier groups includes a plurality of consecutive subcarriers, a plurality of non-consecutive subcarriers, or a combination of consecutive and non-consecutive subcarriers according to a deterministic structure. The map is signaled using an OFDMA PPDU comprising a legacy preamble portion configured to silence legacy users that do not use OFDMA communications, an OFDMA preamble portion indicating the map, and a data portion.

Claims

1. A method for communication in a wireless local area network (WLAN), the method comprising:

transmitting, by a network component, a physical layer (PHY) protocol data unit (PPDU) comprising;

a legacy preamble, the legacy preamble comprising a legacy short training field (L-STF) and a legacy long training field (L-LTF) in a legacy format, and

a non-legacy part comprising a second long training field (LTF), wherein a bandwidth of the WLAN PPDU comprises;

64 subcarriers per 20 MHz in the legacy preamble, and 256 or more subcarriers per 20 MHz in the non-legacy part.

2. The method of claim 1, the second LTF being used for channel estimation for a data transmission or a sounding packet transmission, and not all subcarriers of a symbol of the second LTF being used for the channel estimation.

3. The method of claim 2, wherein every N-th subcarrier of the symbol of the second LTF is used for the channel estimation, and wherein N is an integer power of 2.

4. The method of claim 1, the PPDU comprising first information for mapping one or more predefined subcarrier groups to one or more stations (STAs) and second information of one or more streams scheduled for each STA,

wherein each subcarrier group of the predefined subcarrier groups is a part of the bandwidth with a size representing a number of subcarriers in the each subcarrier group and with a location where the part of the bandwidth is located within the bandwidth.

5. The method of claim 4, wherein at least a first size and a second size are predefined for the predefined subcarrier groups, and wherein the first size is an integer multiple of the second size.

6. The method of claim 4, wherein the PPDU comprises a SIG field, wherein the SIG field comprises the first information and the second information, and wherein the mapping is indicated by a sequence of subcarrier groups and a sequence of STAs.

7. The method of claim 4, wherein the non-legacy part further comprises a data portion, wherein the data portion comprises the first information, and wherein the mapping is indicated by a sequence of sub-mapping fields, each sub-mapping field of the sequence of sub-mapping fields comprising a STA identifier (ID) and a subcarrier group index.

8. An apparatus for communication in a wireless local area network (WLAN), the apparatus comprising:

a non-transitory memory storage comprising instructions; and

one or more processors in communication with the non-transitory memory storage, wherein the one or more processors execute the instructions to;

transmit a physical layer (PHY) protocol data unit (PPDU) comprising;

a legacy preamble, the legacy preamble comprising a legacy short training field (L-STF) and a legacy long training field (L-LTF) in a legacy format, and

a non-legacy part comprising a second long training field (LTF), wherein a bandwidth of the PPDU comprises;

64 subcarriers per 20 MHz in the legacy preamble, and 256 or more subcarriers per 20 MHz in the non-legacy part.

9. The apparatus of claim 8, the second LTF being used for channel estimation for a data transmission or a sounding packet transmission, and not all subcarriers of a symbol of the second LTF being used for the channel estimation.

10. The apparatus of claim 9, wherein every N-th subcarrier of the symbol of the second LTF is used for the channel estimation, and wherein N is an integer power of 2.

11. The apparatus of claim 8, the PPDU comprising first information for mapping one or more predefined subcarrier groups to one or more stations (STAs) and second information of one or more streams scheduled for each STA,

wherein each subcarrier group of the predefined subcarrier groups is a part of the bandwidth with a size representing a number of subcarriers in the each subcarrier group and with a location where the part of the bandwidth is located within the bandwidth.

12. The apparatus of claim ii, wherein at least a first size and a second size are predefined for the predefined subcarrier groups, and wherein the first size is an integer multiple of the second size.

13. The apparatus of claim ii, wherein the PPDU comprises a SIG field, wherein the SIG field comprises the first information and the second information, and wherein the mapping is indicated by a sequence of subcarrier groups and a sequence of STAs.

14. The apparatus of claim ii, wherein the non-legacy part further comprises a data portion, wherein the data portion comprises the first information, and wherein the mapping is indicated by a sequence of sub-mapping fields, each sub-mapping field of the sequence of sub-mapping fields comprising a STA identifier (ID) and a subcarrier group index.

15. A method for communication in a wireless local area network (WLAN), the method comprising:

receiving, by a station (STA), a physical layer (PHY) protocol data unit (PPDU) comprising;

a legacy preamble, the legacy preamble comprising a legacy short training field (L-STF) and a legacy long training field (L-LTF) in a legacy format, and,

a non-legacy part comprising a second long training field (LTF); and

processing, by the STA, the PPDU, the processing comprising;

obtaining the legacy preamble on 64 subcarriers per 20 MHz in a bandwidth of the PPDU; and

obtaining the non-legacy part on 256 or more subcarriers per 20 MHz in the bandwidth of the PPDU.

16. The method of claim 15, wherein the processing comprises:

using the second LTF for channel estimation for a data transmission or a sounding packet transmission, and not all subcarriers of a symbol of the second LTF being used for the channel estimation.

17. The method of claim 16, wherein the using the second LTF for the channel estimation comprises:

using every N-th subcarrier of the symbol of the second LTF for the channel estimation, wherein N is an integer power of 2.

18. The method of claim 15, the PPDU comprising first information for mapping one or more predefined subcarrier groups to one or more stations (STAs) and second information of one or more streams scheduled for each STA,

wherein each subcarrier group of the predefined subcarrier groups is a part of the bandwidth with a size representing a number of subcarriers in the each subcarrier group and with a location where the part of the bandwidth is located within the bandwidth.

19. The method of claim 18, wherein at least a first size and a second size are predefined for the predefined subcarrier groups, and wherein the first size is an integer multiple of the second size.

20. The method of claim 18, wherein the PPDU comprises a SIG field, wherein the SIG field comprises the first information and the second information, and wherein the mapping is indicated by a sequence of subcarrier groups and a sequence of STAs.

21. The method of claim 18, wherein the non-legacy part further comprises a data portion, wherein the data portion comprises the first information, and wherein the mapping is indicated by a sequence of sub-mapping fields, each sub-mapping field of the sequence of sub-mapping fields comprising a STA identifier (ID) and a subcarrier group index.

22. An apparatus supporting communication in a wireless local area network (WLAN), the apparatus comprising:

a non-transitory memory storage comprising instructions; and

one or more processors in communication with the non-transitory memory storage, wherein the one or more processors execute the instructions to;

receive a physical layer (PHY) protocol data unit (PPDU) comprising;

a legacy preamble, the legacy preamble comprising a legacy short training field (L-STF) and a legacy long training field (L-LTF) in a legacy format, and,

a non-legacy part comprising a second long training field (LTF); and

process the PPDU by;

obtaining the legacy preamble on 64 subcarriers per 20 MHz in a bandwidth of the PPDU; and

obtaining the non-legacy part on 256 or more subcarriers per 20 MHz in the bandwidth of the PPDU.

23. The apparatus of claim 22, wherein the instructions to process comprise instructions to:

use the second LTF for channel estimation for a data transmission or a sounding packet transmission, not all subcarriers of a symbol of the second LTF being used for the channel estimation.

24. The apparatus of claim 23, wherein the instructions to use the second LTF for the channel estimation comprise instructions to:

use every N-th subcarrier of the symbol of the second LTF, wherein N is an integer power of 2.

25. The apparatus of claim 22, the PPDU comprising first information for mapping one or more predefined subcarrier groups to one or more stations (STAs) and second information of one or more streams scheduled for each STA,

wherein each subcarrier group of the predefined subcarrier groups is a part of the bandwidth with a size representing a number of subcarriers in the each subcarrier group and with a location where the part of the bandwidth is located within the bandwidth.

26. The apparatus of claim 25, wherein at least a first size and a second size are predefined for the predefined subcarrier groups, and wherein the first size is an integer multiple of the second size.

27. The apparatus of claim 25, wherein the PPDU comprises a SIG field, wherein the SIG field comprises the first information and the second information, and wherein the mapping is indicated by a sequence of subcarrier groups and a sequence of STAs.

28. The apparatus of claim 25, wherein the non-legacy part further comprises a data portion, wherein the data portion comprises the first information, and wherein the mapping is indicated by a sequence of sub-mapping fields, each sub-mapping field of the sequence of sub-mapping fields comprising a STA identifier (ID) and a subcarrier group index.