High efficiency WLAN preamble structure

Patent metadata

Field	Value
Publication number	US-9780919-B2
Application number	US-201414322048-A
Country	US
Kind code	B2
Filing date	Jul 2, 2014
Priority date	Jul 5, 2013
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

Aspects of the present disclosure provide example preamble formats with repeated signal (SIG) fields that may help provide backwards compatibility and help address the effects of larger delay spreads in various wireless bands (e.g., WiFi bands).

First claim

What is claimed is:

1. A method for wireless communications, comprising:
generating a packet having a preamble decodable by a first type of device having a first set of capabilities and a second type of device having a second set of capabilities, wherein the preamble comprises a SIG field decodable by the first type of device and at least one repeated signal (SIG) field, wherein a guard interval is positioned between the SIG field decodable by the first type of device and at least a first portion of the repeated SIG field, wherein the SIG field and the repeated SIG field is repeated in a manner that allow the first type of device to detect a type of the packet, wherein the repeated SIG field that provides delay spread protection to at least one of the first type of device or second type of device, and wherein the repeated SIG field is decodable by the second type of device but not the first type of device; and
transmitting the packet.

2. The method of claim 1 , wherein:
an indication of a type of packet is provided to the second type of device via an orthogonal rail of the SIG field decodable by the first type of device.

3. The method of claim 1 , wherein an indication of a type of the packet is provided via an orthogonal rail of a SIG field decodable by the first type of device.

4. The method of claim 1 , wherein an indication of a type of the packet is provided via a checksum in the repeated SIG field.

5. The method of 1 , wherein the repeated SIG field is repeated in a manner that allows the first type of device to detect the type of the packet by rotating at least one symbol of the repeated SIG field relative to the SIG field decodable by the first type of device.

6. The method of claim 1 , wherein a second portion of the repeated SIG field is also preceded by a guard interval.

7. The method of claim 1 , wherein a second portion of the repeated SIG field is truncated relative to a first portion of the repeated SIG field.

8. The method of claim 1 , wherein at least a portion of the preamble after the repeated SIG field is transmitted using an increased symbol duration or increased cyclic prefix relative to one or more fields of the preamble to provide delay spread protection.

9. The method of claim 8 , wherein an indication of a type of delay spread protection is signaled prior to an end of the repeated SIG field.

10. The method of claim 1 , wherein the repeated SIG field is repeated in a manner that allows the first type of device to detect the type of the packet by repeating the at least one repeated SIG field in time.

11. The method of claim 1 , wherein the repeated SIG field is repeated in a manner that allows the first type of device to detect the type of the packet by repeating the at least one repeated SIG field in frequency.

12. The method of claim 1 , wherein the at least one repeated SIG field comprises:
a first repeated SIG field that is decodable by the second type of device, but not the first type of device; and
a second repeated SIG field that is decodable by at least the first type of device.

13. The method of claim 1 , wherein at least a portion of the packet is transmitted with a lower rate than at least a portion of the preamble.

14. The method of claim 1 , wherein the preamble comprises at least two repeated SIG fields.

15. The method of claim 14 , wherein at least one of the repeated SIG field is repeated in time.

16. The method of claim 14 , wherein at least one of the repeated SIG field is repeated in frequency.

17. The method of claim 14 , wherein the repeated SIG field comprises at least one repeated high efficiency (HE)-SIG0 field and at least one repeated HE-SIG1 field.

18. The method of claim 1 , wherein the at least one repeated signal (SIG) field comprises a partially repeated SIG field.

19. The method of claim 18 , wherein the partially repeated SIG field is transmitted:
using a set of tones to transmit a first symbol of the at least one repeated SIG field; and
using a limited subset of the set of tones to transmit a second symbol of the at least one repeated SIG field.

20. A method for wireless communications, comprising:
receiving a packet having a preamble decodable by a first type of device having a first set of capabilities and a second type of device having a second set of capabilities, wherein the preamble comprises a SIG field decodable by the first type of device and at least one repeated signal (SIG) field, wherein a guard interval is positioned between the SIG field decodable by the first type of device and at least a first portion of the repeated SIG field, wherein the SIG field and the repeated SIG field is repeated in a manner that allow the first type of device to detect a type of the packet, wherein the repeated SIG field that provides delay spread protection to at least one of the first type of device or second type of device, and wherein the repeated SIG field is decodable by the second type of device but not the first type of device; and
processing the repeated SIG field.

21. The method of claim 20 , wherein:
an indication of a type of packet is provided to the second type of device via an orthogonal rail of the SIG field decodable by the first type of device.

22. The method of claim 20 , wherein an indication of a type of the packet is provided via an orthogonal rail of a SIG field decodable by the first type of device.

23. The method of claim 20 , wherein an indication of a type of the packet is provided via a checksum in the repeated SIG field.

24. The method of claim 20 , wherein the repeated SIG field is repeated in a manner that allows the first type of device to detect the type of the packet by rotating at least one symbol of the repeated SIG field relative to the SIG field decodable by the first type of device.

25. The method of claim 20 , further comprising determining a type of the packet via correlation of repeated portions of the repeated SIG field.

26. The method of claim 20 , wherein at least a portion of the preamble after the repeated SIG field is transmitted using an increased symbol duration or increased cyclic prefix relative to one or more fields of the preamble to provide delay spread protection.

27. The method of claim 26 , wherein at least a portion of the packet after the repeated SIG field in the preamble is transmitted with a larger cyclic prefix relative to one or more fields of the preamble and at least portion after that is transmitted with a longer symbol durations.

28. The method of claim 26 , wherein portions of the packet after the at least a portion transmitted with an increased symbol duration or increased cyclic prefix are transmitted with normal symbol duration.

29. The method of claim 26 , wherein an indication of a type of delay spread protection is signaled prior to an end of the repeated SIG field.

30. The method of claim 29 , wherein the repeated SIG field is repeated in a manner that allows the first type of device to detect the type of the packet by repeating the at least one repeated SIG field in time.

31. The method of claim 29 , wherein the repeated SIG field is repeated in a manner that allows the first type of device to detect the type of the packet by repeating the at least one repeated SIG field in frequency.

32. The method of claim 20 , wherein the at least one repeated

Assignees

• Qualcomm Inc
• Quallcomm Incorporated

Inventors

• Vermani Sameer
• Tian Bin
• Van Zelst Albert
• Van Nee Didier Johannes Richard
• Tandra Rahul
• Doan Dung Ngoc
• Tian Tao

Classifications

• H04W74/0808

  using carrier sensing, e.g. carrier sense multiple access [CSMA] · CPC title

• H04W56/0035

  detecting errors in frequency or phase · CPC title

• H04L5/0053

  Allocation of signalling, i.e. of overhead other than pilot signals · CPC title

• H04L1/0007

  by modifying the frame length · CPC title

• H04L27/2657

  Carrier synchronisation · CPC title