Systems and methods for range extension of wireless communication in sub gigahertz bands

• US 9,191,923 B2
• Filed: 04/13/2012
• Issued: 11/17/2015
• Est. Priority Date: 04/15/2011
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Taghavi Nasrabadi, Mohammad Hossein, Sampath, Hemanth, Jones, Vincent K. IV
• Primary Examiner(s): LI, GUANG W
• Application Number:
  US13/447,149
• Publication Number:
  US 20120263107A1
• Time in Patent Office: 1,313 Days
• Field of Search: 370/328
• US Class Current: 1/1
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/001 applied to control information
• CPC Class Codes: H04L 1/0013 Rate matching, e.g. puncturing or repetition of code symbols
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/26132 using repetition
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal

Abstract

Systems, methods, and devices to enable range extension for wireless communication in sub-gigahertz bands are described herein. In some aspects, portions of packets are repeated in time and/or space when transmitting the packet in order to increase the chance that the packet can be decoded. The repetition of portions of the packet may be based, in part, on the channel characteristics of the channel over which the packet is sent. In some aspects, portions of packets are transmitted over a smaller bandwidth with increased power per frequency range.

Claims

1. A method for wireless communication, the method comprising:

transmitting, over a communication channel, a first packet comprising a training sequence repeated a number of times and a first data portion;

determining information identifying a characteristic of the communication channel, the characteristic indicating a quality of the communication channel;

determining an increased or decreased indication of whether a second packet transmitted over the communication channel is decodable by a receiver based on the characteristic indicating the quality of the communication channel;

determining whether a modulation rate for the second packet satisfies a threshold modulation rate;

modifying the number of times to repeat the training sequence in the second packet based on the increased or decreased indication of whether the second packet transmitted over the communication channel is decodable and further based on determining whether the modulation rate satisfies the threshold modulation rate, the training sequence comprising at least one or more of a short training field or a long training field, wherein the number of times to repeat the training sequence is modified by increasing or decreasing the number of times to repeat the training sequence; and

transmitting the second packet comprising the training sequence repeated the modified number of times and a second data portion.

2. The method of claim 1, wherein the training sequence is repeated in the time-domain.

3. The method of claim 1, wherein the training sequence is repeated in the frequency-domain.

4. The method of claim 3, wherein the training sequence is repeated over a contiguous frequency range.

5. The method of claim 3, wherein the training sequence is repeated over a non-contiguous frequency range.

6. The method of claim 1, wherein the training sequence is repeated in the time-domain and the frequency-domain.

7. The method of claim 1, wherein the second data portion is repeated based on the determined information.

8. The method of claim 1, wherein a coding rate of the second packet is adjusted based on the determined information.

9. The method of claim 1, wherein the training sequence comprises the short training field and the long training field.

10. The method of claim 1, further comprising modifying a second number of times to repeat a signal field in the second packet based on the determined information.

11. A method for wireless communication, the method comprising:

receiving, over a communication channel, a first packet comprising a training sequence repeated a number of times and a first data portion;

receiving, over the communication channel, a second packet comprising the training sequence repeated a modified number of times and a second data portion, the number of times the training sequence is repeated in the second packet being modified by increasing or decreasing the number of times to repeat the training sequence based on a determination of an increased or decreased indication of whether the second packet transmitted over the communication channel is decodable and further based on a determination of whether a modulation rate for the second packet satisfies a threshold modulation rate, wherein the training sequence comprises at least one or more of a short training field or a long training field; and

determining the modified number of times the training sequence is repeated in the second packet.

12. The method of claim 11, wherein the training sequence is repeated in the time-domain.

13. The method of claim 11, wherein the training sequence is repeated in the frequency-domain.

14. The method of claim 13, wherein the training sequence is repeated over a contiguous frequency range.

15. The method of claim 13, wherein the training sequence is repeated over a non-contiguous frequency range.

16. The method of claim 11, wherein the training sequence is repeated in the time-domain and the frequency-domain.

17. The method of claim 11, wherein the training sequence comprises the short training field and the long training field.

18. The method of claim 11, further comprising determining a second number of times at least one or more of a signal field or the second data portion is repeated based on the determined modified number of times the training sequence is repeated in the second packet.

19. The method of claim 11, further comprising determining a frequency range over which the second packet is received based on the determined modified number of times the training sequence is repeated in the second packet.

20. The method of claim 11, further comprising transmitting a request to a wireless device that transmitted the first packet, the request including a request to repeat portions of packets transmitted.

21. The method of claim 20, wherein transmitting the request is based on determination of a channel characteristic of the communication channel over which the first packet is received.

22. The method of claim 11, wherein determining the modified number of times the training sequence is repeated in the second packet comprises comparing a correlation property of the training sequence over multiple time segments or frequency ranges.

23. An apparatus for wireless communication, the apparatus comprising:

a transmitter configured to transmit, over a communication channel, a first packet comprising a training sequence repeated a number of times and a first data portion;

a processor configured to;

determine information identifying a characteristic of the communication channel, the characteristic indicating a quality of the communication channel;

determine an increased or decreased indication of whether a second packet transmitted over the communication channel is decodable by a receiver based on the characteristic indicating the quality of the communication channel;

determine whether a modulation rate for the second packet satisfies a threshold modulation rate; and

modify the number of times to repeat the training sequence in the second packet based on the increased or decreased indication of whether the second packet transmitted over the communication channel is decodable and further based on determining whether the modulation rate satisfies the threshold modulation rate, the training sequence comprising at least one or more of a short training field or a long training field, wherein the number of times to repeat the training sequence is modified by increasing or decreasing the number of times to repeat the training sequence; and

wherein the transmitter is configured to transmit the second packet comprising the training sequence repeated the modified number of times and a second data portion.

24. The apparatus of claim 23, wherein the training sequence is repeated in the time-domain.

25. The apparatus of claim 23, wherein the training sequence is repeated in the frequency-domain.

26. The apparatus of claim 25, wherein the training sequence is repeated over a contiguous frequency range.

27. The apparatus of claim 25, wherein the training sequence is repeated over a non-contiguous frequency range.

28. The apparatus of claim 23, wherein the training sequence is repeated in the time-domain and the frequency-domain.

29. The apparatus of claim 23, wherein the second data portion is repeated based on the determined information.

30. The apparatus of claim 23, wherein a coding rate of the second packet is adjusted based on the determined information.

31. The apparatus of claim 23, wherein the training sequence comprises the short training field and the long training field.

32. The apparatus of claim 23, wherein the processor is further configured to modify a second number of times to repeat a signal field in the second packet based on the determined information.

33. An apparatus for wireless communication, the apparatus comprising:

a receiver configured to;

receive, over a communication channel, a first packet comprising a training sequence repeated a number of times and a first data portion; and

receive, over the communication channel, a second packet comprising the training sequence repeated a modified number of times and a second data portion, the number of times the training sequence is repeated in the second packet being modified by increasing or decreasing the number of times to repeat the training sequence based on a determination of an increased or decreased indication of whether the second packet transmitted over the communication channel is decodable and further based on a determination of whether a modulation rate for the second packet satisfies a threshold modulation rate, wherein the training sequence comprises at least one or more of a short training field or a long training field; and

a processor configured to determine the modified number of times the training sequence is repeated in the second packet.

34. The apparatus of claim 33, wherein the training sequence is repeated in the time-domain.

35. The apparatus of claim 33, wherein the training sequence is repeated in the frequency-domain.

36. The apparatus of claim 35, wherein the training sequence is repeated over a contiguous frequency range.

37. The apparatus of claim 36, wherein the training sequence is repeated over a non-contiguous frequency range.

38. The apparatus of claim 33, wherein the training sequence is repeated in the time-domain and the frequency-domain.

39. The apparatus of claim 33, wherein the training sequence comprises the short training field and the long training field.

40. The apparatus of claim 33, wherein the processor is further configured to determine a second number of times at least one or more of a signal field or the second data portion is repeated based on the determined modified number of times the training sequence is repeated in the second packet.

41. The apparatus of claim 33, wherein the processor is further configured to determine a frequency range over which the second packet is received based on the determined modified number of times the training sequence is repeated in the second packet.

42. The apparatus of claim 33, further comprising a transmitter configured to transmit a request to a wireless device that transmitted the first packet, the request including a request to repeat portions of packets transmitted.

43. The apparatus of claim 42, wherein transmitting the request is based on determination of a channel characteristic of the communication channel over which the first packet is received.

44. The apparatus of claim 33, wherein determining the modified number of times the training sequence is repeated in the second packet comprises comparing a correlation property of the training sequence over multiple time segments or frequency ranges.

45. An apparatus for wireless communication, the apparatus comprising:

means for transmitting, over a communication channel, a first packet comprising a training sequence repeated a number of times and a first data portion;

means for determining information identifying a characteristic of the communication channel, the characteristic indicating a quality of the communication channel;

means for determining an increased or decreased indication of whether a second packet transmitted over the communication channel is decodable by a receiver based on the characteristic indicating the quality of the communication channel;

means for determining whether a modulation rate for the second packet satisfies a threshold modulation rate;

means for modifying the number of times to repeat the training sequence in the second packet based on the increased or decreased indication of whether the second packet transmitted over the communication channel is decodable and further based on determining whether the modulation rate satisfies the threshold modulation rate, the training sequence comprising at least one or more of a short training field or a long training field, wherein the number of times to repeat the training sequence is modified by increasing or decreasing the number of times to repeat the training sequence; and

means for transmitting the second packet comprising the training sequence repeated the modified number of times and a second data portion.

46. The apparatus of claim 45, wherein the training sequence is repeated in the time-domain.

47. The apparatus of claim 45, wherein the training sequence is repeated in the frequency-domain.

48. The apparatus of claim 47, wherein the training sequence is repeated over a contiguous frequency range.

49. The apparatus of claim 47, wherein the training sequence is repeated over a non-contiguous frequency range.

50. The apparatus of claim 45, wherein the training sequence is repeated in the time-domain and the frequency-domain.

51. The apparatus of claim 45, wherein the second data portion is repeated based on the determined information.

52. The apparatus of claim 45, wherein a coding rate of the second packet is adjusted based on the determined information.

53. The apparatus of claim 45, wherein the training sequence comprises the short training field and the long training field.

54. The apparatus of claim 45, further comprising means for modifying a second number of times to repeat a signal field in the second packet based on the determined information.

55. An apparatus for wireless communication, the apparatus comprising:

means for receiving, over a communication channel, a first packet comprising a training sequence repeated a number of times and a first data portion;

means for receiving, over the communication channel, a second packet comprising the training sequence repeated a modified number of times and a second data portion, the number of times the training sequence is repeated in the second packet being modified by increasing or decreasing the number of times to repeat the training sequence based on a determination of an increased or decreased indication of whether the second packet transmitted over the communication channel is decodable and further based on a determination of whether a modulation rate for the second packet satisfies a threshold modulation rate, wherein the training sequence comprises at least one or more of a short training field or a long training field; and

means for determining the modified number of times the training sequence is repeated in the second packet.

56. The apparatus of claim 55, wherein the training sequence is repeated in the time-domain.

57. The apparatus of claim 55, wherein the training sequence is repeated in the frequency-domain.

58. The apparatus of claim 57, wherein the training sequence is repeated over a contiguous frequency range.

59. The apparatus of claim 57, wherein the training sequence is repeated over a non-contiguous frequency range.

60. The apparatus of claim 55, wherein the training sequence is repeated in the time-domain and the frequency-domain.

61. The apparatus of claim 55, wherein the training sequence comprises the short training field and the long training field.

62. The apparatus of claim 55, further comprising means for determining a second number of times at least one or more of a signal field or the second data portion is repeated based on the determined modified number of times the training sequence is repeated in the second packet.

63. The apparatus of claim 55, further comprising means for determining a frequency range over which the second packet is received based on the determined modified number of times the training sequence is repeated in the second packet.

64. The apparatus of claim 55, further comprising means for transmitting a request to a wireless device that transmitted the first packet, the request including a request to repeat portions of packets transmitted.

65. The apparatus of claim 64, wherein transmitting the request is based on determination of a channel characteristic of the communication channel over which the first packet is received.

66. The apparatus of claim 55, wherein determining the modified number of times the training sequence is repeated in the second packet comprises comparing a correlation property of the training sequence over multiple time segments or frequency ranges.

67. A non-transitory computer readable medium comprising instructions that when executed cause an apparatus to perform a method of wireless communication, the method comprising:

transmitting, over a communication channel, a first packet comprising a training sequence repeated a number of times and a first data portion;

determining information identifying a characteristic of the communication channel, the characteristic indicating a quality of the communication channel;

determining an increased or decreased indication of whether a second packet transmitted over the communication channel is decodable by a receiver based on the characteristic indicating the quality of the communication channel;

determining whether a modulation rate for the second packet satisfies a threshold modulation rate;

modifying the number of times to repeat the training sequence in the second packet based on the increased or decreased indication of whether the second packet transmitted over the communication channel is decodable and further based on determining whether the modulation rate satisfies the threshold modulation rate, the training sequence comprising at least one or more of a short training field or a long training field, wherein the number of times to repeat the training sequence is modified by increasing or decreasing the number of times to repeat the training sequence; and

transmitting the second packet comprising the training sequence repeated the modified number of times and a second data portion.

68. The non-transitory computer readable medium of claim 67, wherein the training sequence is repeated in the time-domain.

69. The non-transitory computer readable medium of claim 67, wherein the training sequence is repeated in the frequency-domain.

70. The non-transitory computer readable medium of claim 69, wherein the training sequence is repeated over a contiguous frequency range.

71. The non-transitory computer readable medium of claim 69, wherein the training sequence is repeated over a non-contiguous frequency range.

72. The non-transitory computer readable medium of claim 67, wherein the training sequence is repeated in the time-domain and the frequency-domain.

73. The non-transitory computer readable medium of claim 67, wherein the second data portion is repeated based on the determined information.

74. The non-transitory computer readable medium of claim 67, wherein a coding rate of the second packet is adjusted based on the determined information.

75. The non-transitory computer readable medium of claim 67, wherein the training sequence comprises the short training field and the long training field.

76. The non-transitory computer readable medium of claim 67, wherein the method further comprises modifying a second number of times to repeat a signal field in the second packet based on the determined information.

77. A non-transitory computer readable medium comprising instructions that when executed cause an apparatus to perform a method of wireless communication, the method comprising:

receiving, over a communication channel, a first packet comprising a training sequence repeated a number of times and a first data portion;

receiving, over the communication channel, a second packet comprising the training sequence repeated a modified number of times and a second data portion, the number of times the training sequence is repeated in the second packet being modified by increasing or decreasing the number of times to repeat the training sequence based on a determination of an increased or decreased indication of whether the second packet transmitted over the communication channel is decodable and further based on a determination of whether a modulation rate for the second packet satisfies a threshold modulation rate, wherein the training sequence comprises at least one or more of a short training field or a long training field; and

determining the modified number of times the training sequence is repeated in the second packet.

78. The non-transitory computer readable medium of claim 77, wherein the training sequence is repeated in the time-domain.

79. The non-transitory computer readable medium of claim 77, wherein the training sequence is repeated in the frequency-domain.

80. The non-transitory computer readable medium of claim 79, wherein the training sequence is repeated over a contiguous frequency range.

81. The non-transitory computer readable medium of claim 79, wherein the training sequence is repeated over a non-contiguous frequency range.

82. The non-transitory computer readable medium of claim 77, wherein the training sequence is repeated in the time-domain and the frequency-domain.

83. The non-transitory computer readable medium of claim 77, wherein the training sequence comprises the short training field and the long training field.

84. The non-transitory computer readable medium of claim 77, wherein the method further comprises determining a second number of times at least one or more of a signal field or the second data portion is repeated based on the determined modified number of times the training sequence is repeated in the second packet.

85. The non-transitory computer readable medium of claim 77, wherein the method further comprises determining a frequency range over which the second packet is received based on the determined modified number of times the training sequence is repeated in the second packet.

86. The non-transitory computer readable medium of claim 77, wherein the method further comprises transmitting a request to a wireless device that transmitted the first packet, the request including a request to repeat portions of packets transmitted.

87. The non-transitory computer readable medium of claim 86, wherein transmitting the request is based on determination of a channel characteristic of the communication channel over which the first packet is received.

88. The non-transitory computer readable medium of claim 77, wherein determining the modified number of times the training sequence is repeated in the second packet comprises comparing a correlation property of the training sequence over multiple time segments or frequency ranges.