PHYSICAL LAYER PROTOCOL DATA UNIT FORMAT IN A HIGH EFFICIENCY WIRELESS LAN

• US 20160007342A1
• Filed: 07/02/2015
• Published: 01/07/2016
• Est. Priority Date: 07/04/2014
• Status: Active Grant

• Current Assignee: Atlas Global Technologies LLC (Acacia Research Corporation)
• Original Assignee: Newracom Inc.
• Inventors: SEOK, Yongho
• Granted Patent: US 10,305,647 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 27/26025 Numerology, i.e. varying one or more of symbol duration, subcarrier spacing, Fourier transform size, sampling rate or down-clocking allocating sub-channels of the transmission path H04L5/003
• CPC Class Codes: H04L 27/2603 Signal structure ensuring backward compatibility with legacy system
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

The present invention provides a new uplink PPDU frame format to support MU-MIMO and OFDMA, and methods, apparatuses, etc. therefor. In an aspect of the present invention, a method by a STA for transmitting an UL PPDU frame to an AP simultaneously with one or more other STAs in a WLAN may include receiving a frame including a parameter for the PPDU frame from the AP; and participating in UL MU PPDU frame transmission based on the parameter.

Claims

1. A method by a Station (STA) for transmitting an Uplink (UL) Physical layer Protocol Data Unit (PPDU) frame to an Access Point (AP) simultaneously with one or more other STAs in a Wireless Local Area Network (WLAN), the method comprising:

receiving a frame including a parameter for the PPDU frame from the AP; and

participating in an UL Multi-User (MU) PPDU frame transmission based on the parameter.

2. The method according to claim 1, wherein the parameter includes a parameter for a guard interval applied to at least one of a High Efficiency-Long Training Field (HE-LTF) field or a Physical layer Service Data Unit (PSDU) of the PPDU frame, and

wherein a guard interval applied to a Legacy-Long Training Field (L-LTF) of the PPDU frame is a predefined value.

3. The method according to claim 1, wherein the guard interval applied to the at least one of the HE-LTF field or the PSDU is a guard interval applied to a 256-Fast Fourier Transform (FFT)-based Orthogonal Frequency Division Multiplexing (OFDM) symbol, and the guard interval applied to the L-LTF is a guard interval applied to a 64-FFT-based OFDM symbol.

4. The method according to claim 2, wherein a parameter for the guard interval applied to the HE-LTF field and a parameter for the guard interval applied to the PSDU are defined as the same parameter.

5. The method according to claim 2, wherein a parameter for the guard interval applied to the HE-LTF field and a parameter for the guard interval applied to the PSDU are defined as separate parameters.

6. The method according to claim 2, wherein the parameter includes a parameter being a basis of determining a number of HE-LTF symbols or elements transmitted by the STA.

7. The method according to claim 6, wherein the parameter being the basis of determining the number of HE-LTF symbols or elements includes a value indicating a number of spatial streams transmitted by the STA.

8. The method according to claim 6, wherein the number of HE-LTF symbols or elements transmitted by the STA is equal to a number of HE-LTF symbols or elements transmitted by each of the one or more other STAs.

9. The method according to claim 6, wherein if a number of spatial streams transmitted by the STA is different from a number of spatial streams transmitted by each of the one or more other STAs, or irrespective of the number of spatial streams transmitted by the STA or the number of spatial streams transmitted by each of the one or more other STAs, the number of HE-LTF symbols or elements transmitted by the STA is equal to a number of HE-LTF symbols or elements transmitted by each of the one or more other STAs.

10. The method according to claim 6, wherein the number of HE-LTF symbols or elements transmitted by the STA is determined according to a maximum number among the number of spatial streams transmitted by the STA and a number of spatial streams transmitted by each of the one or more other STAs.

11. A method for receiving an Uplink (UL) Physical layer Protocol Data Unit (PPDU) frame simultaneously from each of a plurality of Stations (STAs) by an Access Point (AP) in a Wireless Local Area Network (WLAN), the method comprising:

transmitting a frame including a parameter for the PPDU frame to be received from each of the plurality of STAs to the plurality of STAs; and

receiving an UL Multi-User (MU) PPDU frame in which the plurality of STAs participate.

12. The method according to claim 11, wherein the parameter includes a parameter for a guard interval applied to at least one of a High Efficiency-Long Training Field (HE-LTF) field or a Physical layer Service Data Unit (PSDU) of the PPDU frame, and

wherein a guard interval applied to a Legacy-Long Training Field (L-LTF) of the PPDU frame is a predefined value.

13. The method according to claim 12, wherein the guard interval applied to the at least one of the HE-LTF field or the PSDU is a guard interval applied to a 256-Fast Fourier Transform (FFT)-based Orthogonal Frequency Division Multiplexing (OFDM) symbol, and

the guard interval applied to the L-LTF is a guard interval applied to a 64-FFT-based OFDM symbol.

14. The method according to claim 12, wherein a parameter for the guard interval applied to the HE-LTF field and a parameter for the guard interval applied to the PSDU are defined as the same parameter.

15. The method according to claim 12, wherein a parameter for the guard interval applied to the HE-LTF field and a parameter for the guard interval applied to the PSDU are defined as separate parameters.

16. The method according to claim 12, wherein the parameter includes a parameter being a basis of determining a number of HE-LTF symbols or elements transmitted by each of the plurality of STAs.

17. The method according to claim 16, wherein the parameter being the basis of determining the number of HE-LTF symbols or elements includes a value indicating a number of spatial streams transmitted by each of the plurality of STAs.

18. The method according to claim 16, wherein the number of HE-LTF symbols or elements transmitted by the STA is equal to a number of HE-LTF symbols or elements transmitted by each of the one or more other STAs.

19. The method according to claim 16, wherein if a number of spatial streams transmitted by each of the plurality of STAs is different from one another, or irrespective of the number of spatial streams transmitted by each of the plurality of STA, the number of HE-LTF symbols or elements transmitted by each of the plurality of STAs is equal to one another.

20. The method according to claim 16, wherein the number of HE-LTF symbols or elements transmitted by each of the one or more other STAs is determined according to a maximum number among the number of spatial streams transmitted by each of the one or more other STAs.

21. A method for transmitting data to a plurality of Stations (STAs) by an Access Point (AP) in a Wireless Local Area Network (WLAN), the method comprising:

generating a High Efficiency-Long Training Field (HE-LTF) field for the plurality of STAs; and

transmitting a Physical layer Protocol Data Unit (PPDU) frame to the plurality of STAs, the PPDU frame including the HE-LTF field and data for the plurality of STAs,

wherein the data for the plurality of STAs are transmitted to different STA on each of a plurality of subchannels, and

wherein a starting point of the HE-LTF field is same across the plurality of STAs and an end point of the HE-LTF field is same across the plurality of STAs.

22. The method according to claim 21, wherein the HE-LTF field includes a plurality of HE-LTF sections in a frequency domain, and a number of HE-LTF elements included in each of the HE-LTF sections is equal across the plurality of STAs.

23. The method according to claim 22, wherein if a different number of spatial streams are transmitted on each of the subchannels, or irrespective of the number of spatial streams transmitted on each of the subchannels, the number of HE-LTF elements is equal across the plurality of subchannels.

24. The method according to claim 22, wherein the number of HE-LTF elements is determined according to the maximum of the numbers of spatial streams transmitted on the plurality of subchannels.

25. The method according to claim 22, wherein if a different number of spatial streams are transmitted on each of the subchannels, or irrespective of the number of spatial streams transmitted on each of the subchannels, a starting point of the HE-LTF section for each of the plurality of subchannels is equal across the plurality of subchannels and an end point of the HE-LTF section for each of the plurality of subchannels is equal across the plurality of subchannels.

26. The method according to claim 22, wherein if each of the plurality of subchannels includes a plurality of HE-LTF elements, the plurality of HE-LTF elements are contiguous in a time domain.

27. The method according to claim 22, wherein if the PPDU frame is transmitted in a Multi User-Multiple Input Multiple Output (MIMO) mode or an Orthogonal Frequency Division Multiple Access (OFDMA) mode, a starting point of the HE-LTF section for each of the plurality of subchannels is equal across the plurality of subchannels and an end point of the HE-LTF section for each of the plurality of subchannels is equal across the plurality of subchannels.

28. The method according to claim 22, wherein Orthogonal Frequency Division Multiplexing (OFDM) symbol duration applied to the HE-LTF sections of each of the plurality of subchannels is equal across the plurality of subchannels, and Guard Interval (GI) applied to the HE-LTF sections of each of the plurality of subchannels is equal across the plurality of subchannels.

29. The method according to claim 21, wherein the plurality of subchannels are defined on one or more channels.

30. The method according to claim 29, wherein one subchannel is allocated without crossing a boundary between a plurality of channels.

31. A method for receiving data from an Access Point (AP) by a Station (STA) of a plurality of STAs in a Wireless Local Area Network (WLAN), the method comprising:

receiving a High Efficiency-Long Training Field (HE-LTF) field in a Physical layer Protocol Data Unit (PPDU) frame; and

receiving data for the STA from among data for the plurality of STAs in the PPDU frame,

wherein the data for the plurality of STAs are transmitted to different STA on each of a plurality of subchannels, and

wherein a starting point of the HE-LTF field is same across the plurality of STAs and an end point of the HE-LTF field is same across the plurality of STAs.

32. The method according to claim 31, wherein the HE-LTF field includes a plurality of HE-LTF sections in a frequency domain, and a number of HE-LTF elements included in each of the HE-LTF sections is equal across the plurality of STAs.

33. The method according to claim 32, wherein if a different number of spatial streams are transmitted on each of the subchannels, or irrespective of the number of spatial streams transmitted on each of the subchannels, the number of HE-LTF elements is equal across the plurality of subchannels.

34. The method according to claim 32, wherein the number of HE-LTF elements is determined according to the maximum of the numbers of spatial streams transmitted on the plurality of subchannels.

35. The method according to claim 32, wherein if a different number of spatial streams are transmitted on each of the subchannels, or irrespective of the number of spatial streams transmitted on each of the subchannels, a starting point of the HE-LTF section for each of the plurality of subchannels is equal across the plurality of subchannels and an end point of the HE-LTF section for each of the plurality of subchannels is equal across the plurality of subchannels.

36. The method according to claim 32, wherein if each of the plurality of subchannels includes a plurality of HE-LTF elements, the plurality of HE-LTF elements are contiguous in a time domain.

37. The method according to claim 32, wherein if the PPDU frame is transmitted in a Multi User-Multiple Input Multiple Output (MIMO) mode or an Orthogonal Frequency Division Multiple Access (OFDMA) mode, a starting point of the HE-LTF section for each of the plurality of subchannels is equal across the plurality of subchannels and an end point of the HE-LTF section for each of the plurality of subchannels is equal across the plurality of subchannels.

38. The method according to claim 32, wherein Orthogonal Frequency Division Multiplexing (OFDM) symbol duration applied to the HE-LTF sections of each of the plurality of subchannels is equal across the plurality of subchannels, and Guard Interval (GI) applied to the HE-LTF sections of each of the plurality of subchannels is equal across the plurality of subchannels.

39. The method according to claim 31, wherein the plurality of subchannels are defined on one or more channels.

40. The method according to claim 39, wherein one subchannel is allocated without crossing a boundary between a plurality of channels.