Training sequence for a radio communications system

• US 6,731,689 B2
• Filed: 02/19/2002
• Issued: 05/04/2004
• Est. Priority Date: 11/30/2000
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: ArrayComm LLC (Ygomi LLC)
• Inventors: Dogan, Mithat C.
• Primary Examiner(s): Bayard, Emmanuel
• Application Number:
  US10/079,620
• Publication Number:
  US 20020122498A1
• Time in Patent Office: 805 Days
• Field of Search: 375/259, 375/363, 375/134, 370/321, 370/506, 370/511
• US Class Current: 375/259
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
• CPC Class Codes: H04L 7/046 using a dotting sequence

Abstract

A training sequence for a radio communications system is provided. According to one aspect of the present invention, the invention includes a core sequence of symbols, a successive repetition of the core sequence, and a marker sequence having a sequence of symbols different from the core sequence.

Claims

1. A training sequence transmission in a radio communications system comprising:

a core sequence of symbols;

a successive repetition of the core sequence, the repetition of the core sequence having a timing ambiguity; and

a marker sequence having a sequence of symbols different from the core sequence, the marker sequence resolving the timing ambiguity of the repetition of the core sequence.

2. The training sequence transmission of claim 1 wherein the core sequence is transmitted as binary symbols and the marker sequence is equal and opposite in sign to the core sequence.

3. The training sequence transmission of claim 1 wherein the core sequence augmented with the marker sequence forms a vector that is orthogonal to a vector formed by the core sequence augmented with the core sequence.

4. The training sequence transmission of claim 1 wherein the marker sequence follows the repetition of the core sequence.

5. The training sequence transmission of claim 1 wherein the marker sequence precedes the repetition of the core sequence.

6. The training sequence transmission of claim 1 wherein the repetition of the core sequence has a duration longer than a maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back.

7. The training sequence transmission of claim 1 wherein the repetition of the core sequence has a duration longer than a duration of a beam forming analysis window plus a maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back.

8. The training sequence transmission of claim 1 wherein the repetition of the core sequence has a duration longer than a the maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back plus a random delay applied by the terminal transmitting the training sequence.

9. The training sequence of claim 1 transmission wherein the repetition of the core sequence comprises a repetition of the core sequence successively a specified number of times.

10. The training sequence of claim 1 transmission wherein the core sequence consists essentially of 12 symbols.

11. The training sequence of claim 1 transmission wherein the core sequence has a normalized cross-correlation of about ⅓

.

12. The training sequence transmission of claim 1 wherein the core sequence has a normalized autocorrelation of about ⅓

.

13. The training sequence transmission of claim 1 wherein an the absolute value of a the mean of the core sequence is about zero.

14. A method comprising:

generating a core sequence of symbols;

generating a successive repetition of the core sequence, the repetition of the core sequence having a timing ambiguity; and

generating a marker sequence having sequence of symbols different from the core sequence;

combining the repetition of the core sequence and marker sequence to form a training sequence, the marker sequence resolving the timing ambiguity of the repetition of the core sequence; and

transmitting the training sequence with a communications burst in a radio communications system.

15. The method of claim 14 wherein transmitting the training sequence comprises transmitting binary symbols and wherein generating the marker sequence comprises generating a marker sequence that is equal and opposite in sign to the core sequence.

16. The method of claim 14 wherein the core sequence augmented with the marker sequence forms a vector that is orthogonal to a vector formed by the core sequence augmented with the core sequence.

17. The method of claim 14 wherein the repetition of the core sequence has a duration longer than a maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back.

18. The method of claim 14 wherein the core sequence has a normalized cross-correlation of about ⅓

.

19. The method of claim 14 wherein the core sequence has a normalized autocorrelation of about ⅓

.

20. The method of claim 14 wherein an the absolute value of a the mean of the core sequence is about zero.

21. A machine-readable medium having stored thereon data representing sequences of instructions which, when executed by a machine, cause the machine to perform operations comprising:

generating a core sequence of symbols;

generating a successive repetition of the core sequence, the repetition of the core sequence having a timing ambiguity; and

generating a marker sequence having sequence of symbols different from the core sequence;

combining the repetition of the core sequence and marker sequence to form a training sequence, the marker sequence resolving the timing ambiguity of the repetition of the core sequence; and

transmitting the training sequence with a communications burst in a radio communications system.

22. The medium of claim 21 wherein transmitting the training sequence comprises transmitting binary symbols and wherein generating the marker sequence comprises generating a marker sequence that is equal and opposite in sign to the core sequence.

23. The medium of claim 21 wherein the core sequence augmented with the marker sequence forms a vector that is orthogonal to a vector formed by the core sequence augmented with the core sequence.

24. The medium of claim 21 wherein the repetition of the core sequence has a duration longer than a the maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back.

25. The medium of claim 21 wherein the core sequence has a normalized cross-correlation of about ⅓

.

26. The medium of claim 21 wherein the core sequence has a normalized autocorrelation of about ⅓

.

27. The medium of claim 21 wherein an the absolute value of a the mean of the core sequence is about zero.

28. A training sequence transmission in a radio communications system comprising:

a core sequence of symbols;

a successive repetition of the core sequence; and

a marker sequence having a sequence of symbols different from the core sequence,

wherein the repetition of the core sequence has a duration longer than a the maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back.

29. The training sequence transmission of claim 28 wherein the core sequence is transmitted as binary symbols and the marker sequence is equal and opposite in sign to the core sequence.

30. The training sequence transmission of claim 28 wherein the core sequence augmented with the marker sequence forms a vector that is orthogonal to a vector formed by the core sequence augmented with the core sequence.

31. The training sequence transmission of claim 28 wherein the repetition of the core sequence has a duration longer than a duration of a beam forming analysis window plus the maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back.

32. The training sequence transmission of claim 28 wherein the repetition of the core sequence has a duration longer than the maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back plus a random delay applied by the terminal transmitting the training sequence.

33. The training sequence of claim 28 transmission wherein the core sequence has a normalized cross-correlation of about ⅓

.

34. The training sequence transmission of claim 28 wherein the core sequence has a normalized autocorrelation of about ⅓

.

35. The training sequence transmission of claim 28 wherein an the absolute value of a the mean of the core sequence is about zero.

36. A method comprising:

generating a core sequence of symbols;

generating a successive repetition of the core sequence; and

generating a marker sequence having sequence of symbols different from the core sequence;

combining the repetition of the core sequence and marker sequence to form a training sequence; and

transmitting the training sequence with a communications burst in a radio communications system

wherein the repetition of the core sequence has a duration longer than a maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back.

37. The method of claim 36 wherein transmitting the training sequence comprises transmitting binary symbols and wherein generating the marker sequence comprises generating a marker sequence that is equal and opposite in sign to the core sequence.

38. The method of claim 36 wherein the core sequence augmented with the marker sequence forms a vector that is orthogonal to a vector formed by the core sequence augmented with the core sequence.

39. The method of claim 36 wherein an the absolute value of a mean of the core sequence is about zero.

40. A machine-readable medium having stored thereon data representing sequences of instructions which, when executed by a machine, cause the machine to perform operations comprising:

generating a core sequence of symbols;

generating a successive repetition of the core sequence; and

generating a marker sequence having sequence of symbols different from the core sequence;

combining the repetition of the core sequence and marker sequence to form a training sequence; and

transmitting the training sequence with a communications burst in a radio communications system

wherein the repetition of the core sequence has a duration longer than a maximum round trip delay time from a terminal transmitting the training sequence to a terminal receiving the training sequence and back.

41. The medium of claim 40 wherein transmitting the training sequence comprises transmitting binary symbols and wherein generating the marker sequence comprises generating a marker sequence that is equal and opposite in sign to the core sequence.

42. The medium of claim 40 wherein the core sequence augmented with the marker sequence forms a vector that is orthogonal to a vector formed by the core sequence augmented with the core sequence.

43. The medium of claim 40 wherein the core sequence has a normalized cross-correlation of about ⅓

.

44. The medium of claim 40 wherein the core sequence has a normalized autocorrelation of about ⅓

.

45. The medium of claim 40 wherein an the absolute value of a mean of the core sequence is about zero.