Method and apparatus for a 1 MHz long training field design

• US 8,750,215 B2
• Filed: 06/25/2012
• Issued: 06/10/2014
• Est. Priority Date: 03/06/2012
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Azizi, Shahrnaz, Kenney, Thomas, Perahia, Eldad
• Primary Examiner(s): LY, ANH VU H
• Application Number:
  US13/532,056
• Publication Number:
  US 20130235714A1
• Time in Patent Office: 715 Days
• Field of Search: None
• US Class Current: 370/328
• CPC Class Codes: H04L 2012/5652 Cell construction, e.g. including header, packetisation, depacketisation, assembly, reassembly
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2666 Acquisition of further OFDM parameters, e.g. bandwidth, subcarrier spacing, or guard interval length
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers

Abstract

An approach is provided for defining a 1 MHz preamble of a packet. The approach involves determining a preamble sequence of a packet, the preamble sequence having a determinable length. The approach also involves causing, at least in part, the preamble sequence to be divided into a predetermined number of blocks. The approach further involves causing, at least in part, a mathematical operation and a summation over the predetermined number of blocks and a corresponding number of received blocks. The approach also involves causing, at least in part, the summation to be maximized to determine the preamble sequence corresponds to one of a first bandwidth or a second bandwidth, the second bandwidth being greater than the first bandwidth, to determine a type of the packet.

Claims

1. A method comprising:

determining a preamble sequence of a packet, the preamble sequence having a determinable length;

causing, at least in part, the preamble sequence to be divided into a predetermined number of blocks;

causing, at least in part, a mathematical operation and a summation over the predetermined number of blocks and a corresponding number of received blocks; and

causing, at least in part, the summation to be maximized to determine the preamble sequence corresponds to one of a first bandwidth or a second bandwidth, the second bandwidth being greater than the first bandwidth, to determine a type of the packet.

2. A method of claim 1, wherein the predetermined number of blocks comprises two or more blocks.

3. A method of claim 2, wherein the predetermined number of blocks are of equal length.

4. A method of claim 1, further comprising:

causing, at least in part, the predetermined number of blocks to be populated using a search program configured to populate the predetermined blocks with any combination of +1'"'"'s and −

1'"'"'s.

5. A method of claim 4, further comprising:

causing, at least in part, the population of the predetermined number of blocks to be randomized by causing, at least in part, the search program to limit the populated values to a maximum of five consecutive equal values.

6. A method of claim 4, further comprising:

causing, at least in part, a power architecture performance reference associated with determining the type of the data packet to be less than 3.9 dB.

7. A method of claim 4, further comprising:

causing, at least in part, a speed of an autocorrelation drop after a short training field to be maximized.

8. A method of claim 1, wherein the first bandwidth is equal to 1 MHz.

9. A method of claim 1, wherein each of the predetermined number of blocks comprises a number of subcarriers, and a predetermined number of the subcarriers are caused to be nulled so as to generate guard tones.

10. A method of claim 1, wherein the division of the blocks causes, at least in part, a preamble sequence that corresponds to the first bandwidth to be orthogonal with a preamble sequence that corresponds to the second bandwidth where each block is in a differential sense orthogonal.

11. A method of claim 1, further comprising:

causing, at least in part, the packet to be received from a transmitting source.

12. A method of claim 1, further comprising:

causing, at least in part, the packet to be transmitted from a transmitting source to a receiver.

13. An apparatus comprising:

at least one processor; and

at least one memory including computer program code for one or more programs,

the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to perform at least the following;

determine a preamble sequence of a packet, the preamble sequence having a determinable length;

cause, at least in part, the preamble sequence to be divided into a predetermined number of blocks;

cause, at least in part, a mathematical operation and a summation over the predetermined number of blocks and a corresponding number of received blocks; and

cause, at least in part, the summation to be maximized to determine the preamble sequence corresponds to one of a first bandwidth or a second bandwidth, the second bandwidth being greater than the first bandwidth, to determine a type of the packet.

14. An apparatus of claim 13, wherein the predetermined number of blocks comprises two or more blocks.

15. An apparatus of claim 14, wherein the predetermined number of blocks are of equal length.

16. An apparatus of claim 13, wherein the apparatus is further caused to:

cause, at least in part, the predetermined number of blocks to be populated using a search program configured to populate the predetermined blocks with any combination of +1'"'"'s and −

1'"'"'s.

17. An apparatus of claim 16, wherein the apparatus is further caused to:

cause, at least in part, the population of the predetermined number of blocks to be randomized by causing, at least in part, the search program to limit the populated values to a maximum of five consecutive equal values.

18. An apparatus of claim 16, wherein the apparatus is further caused to:

cause, at least in part, a power architecture performance reference associated with determining the type of the data packet to be less than 3.9 dB.

19. An apparatus of claim 16, wherein the apparatus is further caused to:

cause, at least in part, a speed of an autocorrelation drop after a short training field to be maximized.

20. An apparatus of claim 13, wherein the first bandwidth is equal to 1 MHz.

21. An apparatus of claim 13, wherein each of the predetermined number of blocks comprises a number of subcarriers, and a predetermined number of the subcarriers are caused to be nulled so as to generate guard tones.

22. An apparatus of claim 13, wherein the division of the blocks causes, at least in part, a preamble sequence that corresponds to the first bandwidth to be orthogonal with a preamble sequence that corresponds to the second bandwidth where each block is in a differential sense orthogonal.

23. An apparatus of claim 13, further comprising a transceiver, wherein the apparatus is further caused to cause, at least in part, the packet to be received from a transmitting source.

24. An apparatus of claim 13, further comprising a transceiver, wherein the apparatus is further caused to cause, at least in part, the packet to be transmitted from a transmitting source to a receiver.

25. A non-transitory computer-readable storage medium carrying one or more sequences of one or more instructions which, when executed by one or more processors, cause an apparatus to at least perform the following:

determine a preamble sequence of a packet, the preamble sequence having a determinable length;

cause, at least in part, the preamble sequence to be divided into a predetermined number of blocks;

cause, at least in part, a mathematical operation and a summation over the predetermined number of blocks and a corresponding number of received blocks; and

cause, at least in part, the summation to be maximized to determine the preamble sequence corresponds to one of a first bandwidth or a second bandwidth, the second bandwidth being greater than the first bandwidth, to determine a type of the packet.

26. A computer-readable storage medium of claim 25, wherein the division of the blocks causes, at least in part, a preamble sequence that corresponds to the first bandwidth to be orthogonal with a preamble sequence that corresponds to the second bandwidth where each block is in a differential sense orthogonal.