Physical layer data unit format

• US 8,165,185 B2
• Filed: 09/29/2009
• Issued: 04/24/2012
• Est. Priority Date: 09/29/2008
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Marvell World Trade Limited (Marvell Technology Group Limited)
• Inventors: Zhang, Hongyuan, Wu, Songping, Lou, Hui-Ling, Nabar, Rohit U.
• Primary Examiner(s): Bayard, Emmanuel
• Application Number:
  US12/569,547
• Publication Number:
  US 20100080266A1
• Time in Patent Office: 938 Days
• Field of Search: 375/130, 375/134, 375/145, 375/260, 375/135, 375/146, 370208-210, 370/328
• US Class Current: 375/135
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04J 13/102 Combining codes
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers

Abstract

In a wireless communication system wherein communication devices exchange information utilizing data units that conform to a first format, wherein the first format includes a short training field (STF) spread with a first spread code and a first cover code, a method is for generating a physical layer (PHY) data unit that conforms to a second format, wherein the PHY data unit is for transmitting PHY information. A first portion of the PHY data unit is generated to indicate the PHY data unit conforms to the second format, wherein the first portion of the PHY data unit includes an STF spread with at least one of a second spread code different than the first spread code or a second cover code different than the first cover code. A second portion of the PHY data unit is generated according to the second format, wherein the second portion of the PHY data unit includes PHY information elements not specified by the first format.

Claims

1. In a wireless communication system wherein communication devices exchange information utilizing data units that conform to a first format, wherein the first format includes a short training field (STF) spread with a first spread code and a first cover code, a method for generating a physical layer (PHY) data unit that conforms to a second format, wherein the PHY data unit is for transmitting PHY information, the method comprising:

generating a first portion of the PHY data unit to indicate the PHY data unit conforms to the second format, wherein the first portion of the PHY data unit includes an STF spread with at least one of a second spread code different than the first spread code or a second cover code different than the first cover code; and

generating a second portion of the PHY data unit according to the second format, wherein the second portion of the PHY data unit includes PHY information elements not specified by the first format.

2. A method according to claim 1, wherein the second spread code is a complementary sequence of the first spread code;

wherein the first portion of the PHY data unit includes the STF spread with the second spread code.

3. A method according to claim 2, wherein the first spread code and the second spread code are complimentary Golay sequences a and b, respectively.

4. A method according to claim 3, wherein the STF of the first format comprises a plurality of consecutive Golay sequences a;

and

wherein the STF of the second format comprises a plurality of consecutive Golay sequences b.

5. A method according to claim 4, wherein the STF of the second format comprises a delimiter field after the plurality of consecutive Golay sequences b;

and

wherein delimiter field includes at least one Golay sequence −

b.

6. A method according to claim 5, wherein a Golay sequence a is included between the STF of the second format and a channel estimation field (CEF).

7. A method according to claim 2, wherein the first format includes a channel estimation field (CEF);

wherein the first portion of the PHY data unit includes the CEF field of the first format.

8. A method according to claim 7, wherein the STF of the PHY data unit includes a delimiter field prior to the CEF field.

9. A method according to claim 8, wherein the STF of the PHY data unit includes a cyclic prefix for the CEF field after the delimiter field.

10. A method according to claim 8, wherein the second format comprises two or more sub-formats;

wherein the method further comprises generating the delimiter field of the PHY data unit to indicate that the PHY data unit conforms to one of the sub-formats.

11. A method according to claim 10, wherein one of the sub-formats corresponds to a data unit used in beamforming training.

12. A communication device for use in a wireless communication system, wherein the communication device exchanges information with other communication devices utilizing data units that conform to a first format, wherein the first format includes a short training field (STF) spread with a first spread code and a first cover code, and utilizing a physical layer (PHY) data unit that conforms to a second format, wherein the PHY data unit is for transmitting PHY information, the communication device comprising:

a PHY data unit generator configured to;

generate a first portion of the PHY data unit to indicate the PHY data unit conforms to the second format, wherein the first portion of the PHY data unit includes an STF spread with at least one of a second spread code different than the first spread code or a second cover code different than the first cover code, and

generate a second portion of the PHY data unit according to the second format, wherein the second portion of the PHY data unit includes PHY information elements not specified by the first format.

13. A communication device according to claim 12, wherein the second spread code is a complementary sequence of the first spread code;

wherein the PHY data unit generator is configured to generate the STF of the PHY data unit spread with the second spread code.

14. A communication device according to claim 13, wherein the first spread code and the second spread code are complimentary Golay sequences a and b, respectively.

15. A communication device according to claim 14, wherein the STF of the first format comprises a plurality of consecutive Golay sequences a;

and

wherein the PHY data unit generator is configured to generate the STF of the PHY data unit to include a plurality of consecutive Golay sequences b.

16. A communication device according to claim 15, wherein the PHY data unit generator is configured to generate the STF of the PHY data unit to include a delimiter field after the plurality of consecutive Golay sequences b;

and

wherein delimiter field includes at least one Golay sequence −

b.

17. A communication device according to claim 16, wherein the PHY data unit generator is configured to include a Golay sequence a between the STF of the second format and a channel estimation field (CEF).

18. A communication device according to claim 12, further comprising a PHY controller to control the PHY data unit generator during implementation of PHY functions.

19. A communication device according to claim 12, further comprising a modulator to modulate the PHY data unit.

20. In a wireless communication system wherein communication devices exchange information utilizing data units that conform to a first format, wherein the first format includes a short training field (STF) spread with a first spread code and a first cover code, a method for processing a physical layer (PHY) data unit that conforms to a second format, wherein the PHY data unit is for transmitting PHY information, the method comprising:

analyzing a first portion of a received data unit to determine if the received data unit is a PHY data unit, wherein the first portion of the received data unit includes an STF;

wherein analyzing the first portion of a received data unit to determine if the received data unit is a PHY data unit comprises determining at least one of

     1) whether the STF of the received data unit is spread with a second spread code different than the first spread code or

     2) whether the STF of the received data unit is spread with a second cover code different than the first cover code;

wherein the method further comprises utilizing PHY information elements in a second portion of the PHY data unit to perform a PHY function if the received data unit is a PHY data unit, wherein the second portion of the PHY data unit conforms to the second format, and wherein the PHY information elements are not specified by the first format.

21. A method according to claim 20, wherein the second spread code is a complementary sequence of the first spread code;

and

wherein analyzing the first portion of the received data unit comprises determining whether the STF of the received data unit is spread with the second spread code.

22. A method according to claim 21, wherein the first spread code and the second spread code are complimentary Golay sequences a and b, respectively.

23. A method according to claim 22, wherein the STF of the first format comprises a plurality of consecutive Golay sequences a;

and

wherein analyzing the first portion of the received data unit comprises determining whether the STF of the received data unit comprises a plurality of consecutive Golay sequences b.

24. A method according to claim 23, wherein the STF of the second format comprises a delimiter field after the plurality of consecutive Golay sequences b;

wherein delimiter field includes at least one Golay sequence −

b;

wherein the method further comprises detecting the delimiter field.

25. A method according to claim 24, wherein a Golay sequence a is included between the STF of the second format and a channel estimation field (CEF).

26. A method according to claim 20, wherein the PHY data unit is a beamforming training (BFT) data unit;

wherein the second portion of the BFT data unit includes BFT information elements not specified by the first format;

wherein utilizing PHY information elements in the second portion of the PHY data unit comprises performing a beamforming training function.

27. A communication device for use in a wireless communication system, wherein the communication device exchanges information with other communication devices utilizing data units that conform to a first format, wherein the first format includes a short training field (STF) spread with a first spread code and a first cover code, and utilizing a physical layer (PHY) data unit that conforms to a second format, wherein the PHY data unit is for transmitting PHY information, the communication device comprising:

a PHY data unit detector configured to;

analyzing a first portion of a received data unit to determine if the received data unit is a PHY data unit, wherein the first portion of the received data unit includes an STF;

determine if the received data unit is a PHY data unit based on determining at least one of

     1) whether the STF of the received data unit is spread with a second spread code different than the first spread code or

     2) whether the STF of the received data unit is spread with a second cover code different than the first cover code;

wherein the communication device further comprises a PHY controller to utilize the PHY information elements in a second portion of the PHY data unit to perform a PHY function if the received data unit is a PHY data unit;

wherein the second portion of the PHY data unit conforms to the second format; and

wherein the PHY information elements are not specified by the first format.

28. A communication device according to claim 27, wherein the second spread code is a complementary sequence of the first spread code;

wherein the PHY data unit detector configured to determine whether the STF of the received data unit is spread with the second spread code.

29. A communication device according to claim 28, wherein the first spread code and the second spread code are complimentary Golay sequences a and b, respectively.

30. A communication device according to claim 29, wherein the STF of the first format comprises a plurality of consecutive Golay sequences a;

and

wherein the PHY data unit detector configured to determine whether the STF of the received data unit comprises a plurality of consecutive Golay sequences b.

31. A communication device according to claim 30, wherein the STF of the second format comprises a delimiter field after the plurality of consecutive Golay sequences b;

wherein delimiter field includes at least one Golay sequence −

b;

wherein the PHY data unit detector configured to detect the delimiter field.

32. A communication device according to claim 27, further comprising a demodulator to demodulate the PHY data unit.

33. A communication device according to claim 27, further comprising a despreader.