METHOD AND APPARATUS FOR SPECTRAL EFFICIENT DATA TRANSMISSION IN SATELLITE SYSTEMS

• US 20160277096A1
• Filed: 09/25/2015
• Published: 09/22/2016
• Est. Priority Date: 03/20/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: WU, Qiang, BLACK, Peter John
• Granted Patent: US 9,893,800 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H03M 13/09 Error detection only, e.g. using cyclic redundancy check [CRC] codes or single parity bit
• CPC Class Codes: H03M 13/258 with turbo codes, e.g. Turbo Trellis Coded Modulation [TTCM]
• CPC Class Codes: H03M 13/2906 using block codes H03M13/2957 takes precedence
• CPC Class Codes: H04B 7/18517 Transmission equipment in earth stations
• CPC Class Codes: H04B 7/18519 Operations control, administration or maintenance
• CPC Class Codes: H04B 7/18543 for adaptation of transmission parameters, e.g. power control for detecting or preventing errors in the information received H04L1/00
• CPC Class Codes: H04B 7/1858 Arrangements for data transmission on the physical system, i.e. for data bit transmission between network components
• CPC Class Codes: H04B 7/18582 Arrangements for data linking, i.e. for data framing, for error recovery, for multiple access
• CPC Class Codes: H04L 1/00 Arrangements for detecting or preventing errors in the information received correcting synchronisation H04L7/00
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0058 Block-coded modulation
• CPC Class Codes: H04L 1/0064 Concatenated codes
• CPC Class Codes: H04L 1/0065 Serial concatenated codes
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames

Abstract

A communication satellite system provides for spectral efficient data transmissions by a gateway to multiple user terminals by way of a satellite. The gateway transmits multiple blocks in a single slot, each block intended for one of the user terminals, where each block is encoded and modulated according to a scheme that may be different for each intended user terminal. Upon re-transmission of a block if that block is lost or received in error, the block may be encoded and modulated according to another scheme that is less spectrally efficient than in the first transmission of the block.

Claims

1. A method comprising:

receiving, at a gateway, channel state information from a plurality of user terminals via a satellite;

encoding by the gateway a plurality of blocks into a plurality of encoded blocks, each block for a corresponding user terminal, wherein the gateway encodes each block according to the value of the channel state information of its corresponding user terminal;

modulating by the gateway the plurality of encoded blocks into a plurality of modulated and encoded blocks, wherein the gateway modulates each encoded block according to the value of the channel state information of its corresponding user terminal; and

transmitting by the gateway to the plurality of user terminals via the satellite a slot comprising the plurality of modulated and encoded blocks.

2. The method of claim 1,

wherein the step of encoding by the gateway comprises a first encoding of a block into a first encoded block according to the value of the channel state information of its corresponding user terminal;

and

wherein the step of modulating by the gateway comprises a first modulating of the first encoded block into a first modulated and encoded block according to the value of the channel state information of its corresponding user terminal;

the method further comprising;

receiving a negative acknowledgement for the first modulated and encoded block;

a second encoding by the gateway of the block into a second encoded block;

a second modulating by the gateway of the second encoded block into a second modulated and encoded block; and

transmitting by the gateway a second slot comprising the second modulated and encoded block.

3. The method of claim 2, wherein the second encoding provides greater error correction than the first encoding.

4. The method of claim 3, wherein the second modulating has a lower order than the first modulating.

5. The method of claim 3, wherein the first modulating and the second modulating are the same modulating scheme.

6. The method of claim 3, wherein the first encoding does not include an outer code.

7. The method of claim 6, wherein the second encoding includes concatenated encoding.

8. The method of claim 2, wherein the second modulating has a lower order than the first modulating.

9. The method of claim 8, wherein the first encoding and the second encoding are the same encoding scheme.

10. The method of claim 1, the slot comprising a pilot for synchronization of the user terminals.

11. The method of claim 1, wherein the step of encoding by the gateway comprises:

selecting a first modulation and coding scheme with no concatenated coding, the first modulation and coding scheme having an error floor; and

encoding and modulating a block according to the first modulation and coding scheme if a target block error rate for the block and the error floor satisfy a relationship, otherwise if the target block error rate for the block and the error floor do not satisfy the relationship then encoding and modulating the block according to a second modulation and coding scheme where the second modulation and coding scheme includes an outer code.

12. The method of claim 11, wherein the relationship is the less than inequality.

13. The method of claim 11, wherein the second modulation and coding scheme includes an inner turbo code and an outer BCH code.

14. A gateway comprising:

a modem; and

at least one processor in communication with the modem, the at least one processor and the modem configured, in combination, to;

demodulate channel state information from a plurality of user terminals via a satellite;

encode a plurality of blocks into a plurality of encoded blocks, each block for a corresponding user terminal, wherein each block is encoded according to the value of the channel state information of its corresponding user terminal;

modulate the plurality of encoded blocks into a plurality of modulated and encoded blocks, wherein each encoded block is modulated according to the value of the channel state information of its corresponding user terminal; and

cause the gateway to transmit the plurality of user terminals via the satellite a slot comprising the plurality of modulated and encoded blocks.

15. The gateway of claim 14, wherein the at least one processor and the modem are further configured, in combination, to:

encode a block into a first encoded block according to the value of the channel state information of its corresponding user terminal;

modulate the first encoded block into a first modulated and encoded block according to the value of the channel state information of its corresponding user terminal; and

in response to the gateway receiving a negative acknowledgement for the first modulated and encoded block, encode the block into a second encoded block, modulate the second encoded block into a second modulated and encoded block, and cause the gateway to transmit a second slot comprising the second modulated and encoded block.

16. The gateway of claim 15, wherein the second encoded block has greater error correction than the first encoded block.

17. The gateway of claim 16, wherein the second modulated and encoded block has a lower order modulation than the first modulated and encoded block.

18. The gateway of claim 16, wherein the at least one processor and the modem are further configured, in combination, to modulate the first encoded block and the second encoded block according to the same modulation scheme.

19. The gateway of claim 16, wherein the at least one processor and the modem are further configured, in combination, to encode the block into the first encoded block without concatenating encoding.

20. The gateway of claim 19, wherein the at least one processor and the modem are further configured, in combination, to encode the block into the second encoded block with concatenated encoding.

21. The gateway of claim 15, wherein the second modulated and encoded block has a lower order modulation than the first modulated and encoded block.

22. The gateway of claim 21, wherein the at least one processor and the modem are further configured, in combination, to encode the block into the first encoded block and encode the block into the second encoded block according to the same encoding scheme.

23. The gateway of claim 14, the slot comprising a pilot for synchronization of the user terminals.

24. The gateway of claim 14, wherein the at least one processor and the modem are further configured, in combination, to

select a first modulation and coding scheme with no concatenated coding, where the first modulation and coding scheme has an error floor;

and

encode and modulate a block according to the first modulation and coding scheme if a target block error rate for the block and the error floor satisfy a relationship, otherwise if the target block error rate for the block and the error floor do not satisfy the relationship, then encode and modulate the block according to a second modulation and coding scheme where the second modulation and coding scheme includes an outer code.

25. The gateway of claim 24, wherein the relationship is the less than inequality.

26. The gateway of claim 24, wherein the second modulation and coding scheme comprises an inner turbo code and an outer BCH code.

27. A non-transitory computer-readable media having stored instructions that, when executed by at least one processor in a gateway, cause the gateway to perform a method comprising:

receiving channel state information from a plurality of user terminals via a satellite;

encoding a plurality of blocks into a plurality of encoded blocks, each block for a corresponding user terminal, wherein each block is encoded according to the value of the channel state information of its corresponding user terminal;

modulating the plurality of encoded blocks into a plurality of modulated and encoded blocks, wherein each encoded block is modulated according to the value of the channel state information of its corresponding user terminal; and

transmitting to the plurality of user terminals via the satellite a slot comprising the plurality of modulated and encoded blocks.

28. The non-transitory computer-readable media of claim 27, the method

wherein the step of encoding in the method comprises a first encoding of a block into a first encoded block according to the value of the channel state information of its corresponding user terminal;

and

wherein the step of modulating in the method comprises a first modulating of the first encoded block into a first modulated and encoded block according to the value of the channel state information of its corresponding user terminal;

the method further comprising;

receiving a negative acknowledgement for the first modulated and encoded block;

a second encoding of the block into a second encoded block;

a second modulating of the second encoded block into a second modulated and encoded block; and

transmitting a second slot comprising the second modulated and encoded block.

29. The non-transitory computer-readable media of claim 28, wherein the second encoding provides greater error correction than the first encoding.

30. The non-transitory computer-readable media of claim 29, wherein the second modulating has a lower order than the first modulating.

31. The non-transitory computer-readable media of claim 29, wherein the first modulating and the second modulating are the same modulating scheme.

32. The non-transitory computer-readable media of claim 29, wherein the first encoding does not include an outer code.

33. The non-transitory computer-readable media of claim 32, wherein the second encoding includes concatenated encoding.

34. The non-transitory computer-readable media of claim 28, wherein the second modulating has a lower order than the first modulating.

35. The non-transitory computer-readable media of claim 34, wherein the first encoding and the second encoding are the same encoding scheme.

36. The non-transitory computer-readable media of claim 27, the slot comprising a pilot for synchronization of the user terminals.

37. The non-transitory computer-readable media of claim 27, wherein the step of encoding in the method comprises:

selecting a first modulation and coding scheme with no concatenated coding, the first modulation and coding scheme having an error floor; and

encoding and modulating a block according to the first modulation and coding scheme if a target block error rate for the block and the error floor satisfy a relationship, otherwise if the target block error rate for the block and the error floor do not satisfy the relationship, then encoding and modulating the block according to a second modulation and coding scheme where the second modulation and coding scheme includes an outer code.

38. The non-transitory computer-readable media of claim 37, wherein the relationship is the less than inequality.

39. The non-transitory computer-readable media of claim 37, wherein the second modulation and coding scheme includes an inner turbo code and an outer BCH code.

40. A gateway comprising:

means for receiving, at the gateway, channel state information from a plurality of user terminals via a satellite;

means for encoding by the gateway a plurality of blocks into a plurality of encoded blocks, each block for a corresponding user terminal, wherein the gateway encodes each block according to the value of the channel state information of its corresponding user terminal;

means for modulating by the gateway the plurality of encoded blocks into a plurality of modulated and encoded blocks, wherein the gateway modulates each encoded block according to the value of the channel state information of its corresponding user terminal; and

means for transmitting by the gateway to the plurality of user terminals via the satellite a slot comprising the plurality of modulated and encoded blocks.

41. The gateway of claim 40,

wherein the means for encoding by the gateway comprises a first encoding of a block into a first encoded block according to the value of the channel state information of its corresponding user terminal;

and

wherein the means for modulating by the gateway comprises a first modulating of the first encoded block into a first modulated and encoded block according to the value of the channel state information of its corresponding user terminal;

wherein if the gateway receives a negative acknowledgement for the first modulated and encoded block, the means for encoding comprises a second encoding by the gateway of the block into a second encoded block, the means for modulating comprises a second modulating by the gateway of the second encoded block into a second modulated and encoded block, and the means for transmitting comprises the gateway transmitting a second slot comprising the second modulated and encoded block.

42. The gateway of claim 41, wherein the second encoding provides greater error correction than the first encoding.

43. The gateway of claim 42, wherein the second modulating has a lower order than the first modulating.

44. The gateway of claim 42, wherein the first modulating and the second modulating are the same modulating scheme.

45. The gateway of claim 42, wherein the first encoding does not include an outer code.

46. The gateway of claim 45, wherein the second encoding includes concatenated encoding.

47. The gateway of claim 41, wherein the second modulating has a lower order than the first modulating.

48. The gateway of claim 47, wherein the first encoding and the second encoding are the same encoding scheme.

49. The gateway of claim 40, the slot comprising a pilot for synchronization of the user terminals.

50. The gateway of claim 40, wherein the means for encoding by the gateway comprises:

selecting a first modulation and coding scheme with no concatenated coding, the first modulation and coding scheme having an error floor; and

encoding and modulating a block according to the first modulation and coding scheme if a target block error rate for the block and the error floor satisfy a relationship, otherwise if the target block error rate for the block and the error floor do not satisfy the relationship, then encoding and modulating the block according to a second modulation and coding scheme where the second modulation and coding scheme includes an outer code.

51. The gateway of claim 50, wherein the relationship is the less than inequality.

52. The gateway of claim 50, wherein the second modulation and coding scheme includes an inner turbo code and an outer BCH code.

53. A method comprising:

transmitting a first slot by a gateway to a satellite, the first slot comprising a block where the block occupies a first fraction of the first slot; and

transmitting a second slot by the gateway to the satellite upon the gateway receiving a negative acknowledgement for the transmission of the block in the first slot, the second slot comprising the block where the block occupies a second fraction of the second slot, the first and second slots having a same transmission time interval, and the second fraction larger than the first fraction.

54. The method of claim 53, wherein the transmitting of the block in the second slot is less spectrally efficient than the transmitting of the block in the first slot.

55. A method of concatenated encoding by a gateway, the method comprising:

providing a block check for a block;

appending the block check to the block;

segmenting the block with appended block check into at least one sub-block;

encoding the at least one sub-block with a systematic encoder to provide parity bits;

providing a sub-block check for each of the at least one sub-block;

appending to each of the at least one sub-block its corresponding sub-block check;

turbo encoding each of the at least one sub-block with appended sub-block check to provide at least one coded sub-block;

grouping the parity bits into at least one parity block;

providing a parity block check for each of the at least one parity block;

appending to each of the at least one parity block its corresponding parity block check; and

turbo encoding each of the at least one parity block with appended parity block check to provide at least one coded parity block.

56. The method of claim 55, further comprising:

transmitting a concatenation of each of the at least one coded sub-block with the at least one coded parity block.

57. The method of claim 55, wherein

the block check for the block is a CRC (Cyclic Redundancy Check) for the block;

the sub-block check for each of the at least one sub-block is a CRC for each of the at least one sub-block; and

the parity block check for each of the at least one parity block is a CRC for each of the at least one parity block.

58. The method of claim 55, wherein the at least one parity block consists of one parity block.

59. A gateway comprising:

a modem; and

at least one processor in communication with the modem, the at least one processor and the modem configured, in combination, to;

provide a block check for a block;

append the block check to the block;

segment the block with appended block check into at least one sub-block;

encode systematically the at least one sub-block to provide parity bits;

provide a sub-block check for each of the at least one sub-block;

append to each of the at least one sub-block its corresponding sub-block check;

turbo encode each of the at least one sub-block with appended sub-block check to provide at least one coded sub-block;

group the parity bits into at least one parity block;

provide a parity block check for each of the at least one parity block;

append to each of the at least one parity block its corresponding parity block check; and

turbo encode each of the at least one parity block with appended parity block check to provide at least one coded parity block.

60. The gateway of claim 59, the at least one processor and the modem further configured, in combination, to:

transmit a concatenation of each of the at least one coded sub-block with the at least one coded parity block.

61. The gateway of claim 59, wherein

the block check for the block is a CRC (Cyclic Redundancy Check) for the block;

the sub-block check for each of the at least one sub-block is a CRC for each of the at least one sub-block; and

the parity block check for each of the at least one parity block is a CRC for each of the at least one parity block.

62. The gateway of claim 59, wherein the at least one parity block consists of one parity block.

63. A gateway comprising:

means for providing a block check for a block;

means for appending the block check to the block;

means for segmenting the block with appended block check into at least one sub-block;

means for encoding the at least one sub-block with a systematic encoder to provide parity bits;

means for providing a sub-block check for each of the at least one sub-block;

means for appending to each of the at least one sub-block its corresponding sub-block check;

means for turbo encoding each of the at least one sub-block with appended sub-block check to provide at least one coded sub-block;

means for grouping the parity bits into at least one parity block;

means for providing a parity block check for each of the at least one parity block;

means for appending to each of the at least one parity block its corresponding parity block check; and

means for turbo encoding each of the at least one parity block with appended parity block check to provide at least one coded parity block.

64. The gateway of claim 63, further comprising:

means for transmitting a concatenation of each of the at least one coded sub-block with the at least one coded parity block.

65. The gateway of claim 63, wherein

the block check for the block is a CRC (Cyclic Redundancy Check) for the block;

the sub-block check for each of the at least one sub-block is a CRC for each of the at least one sub-block; and

the parity block check for each of the at least one parity block is a CRC for each of the at least one parity block.

66. The gateway of claim 63, wherein the at least one parity block consists of one parity block.

67. A non-transitory computer-readable medium having stored instructions that, when executed by at least one processor in a gateway, cause the gateway to perform a method comprising:

providing a block check for a block;

appending the block check to the block;

segmenting the block with appended block check into at least one sub-block;

encoding the at least one sub-block with a systematic encoder to provide parity bits;

providing a sub-block check for each of the at least one sub-block;

appending to each of the at least one sub-block its corresponding sub-block check;

turbo encoding each of the at least one sub-block with appended sub-block check to provide at least one coded sub-block;

grouping the parity bits into at least one parity block;

providing a parity block check for each of the at least one parity block;

appending to each of the at least one parity block its corresponding parity block check; and

turbo encoding each of the at least one parity block with appended parity block check to provide at least one coded parity block.

68. The non-transitory computer-readable medium of claim 67, the method performed by the gateway further comprising:

transmitting a concatenation of each of the at least one coded sub-block with the at least one coded parity block.

69. The non-transitory computer-readable medium of claim 67, wherein

the block check for the block is a CRC (Cyclic Redundancy Check) for the block;

the sub-block check for each of the at least one sub-block is a CRC for each of the at least one sub-block; and

the parity block check for each of the at least one parity block is a CRC for each of the at least one parity block.

70. The non-transitory computer-readable medium of claim 67, wherein the at least one parity block consists of one parity block.

71. A method of concatenated decoding by a user terminal, the method comprising:

turbo decoding a received at least one coded sub-block to provide a first estimate of at least one sub-block;

concatenating the first estimate of the at least one sub-block to provide a first estimate of a block with a first estimate of a block check;

determining whether the first estimate of the block check passes or fails; and

provided the first estimate of the block check fails;

turbo decoding a received at least one coded parity block to provide an estimate of at least one parity block;

outer decoding the first estimate of the at least one sub-block using the estimate of the at least one parity block to provide a second estimate of the at least one sub-block;

concatenating the second estimate of the at least one sub-block to provide a second estimate of the block with a second estimate of the block check; and

determining whether the second estimate of the block check passes or fails.

72. The method of claim 71, wherein each of the received at least one coded sub-block includes a received coded sub-block check, wherein the step of turbo decoding the received at least one coded sub-block comprises stopping iterations of the turbo decoding based upon the received coded sub-block check for each received at least one coded sub-block.

73. The method of claim 72, wherein the step of determining whether the first estimate of the block check passes or fails comprises a cyclic redundancy check applied to the block check.

74. A user terminal comprising:

a modem; and

at least one processor in communication with the modem, the at least one processor and the modem configured, in combination, to;

turbo decode a received at least one coded sub-block to provide a first estimate of at least one sub-block;

concatenate the first estimate of the at least one sub-block to provide a first estimate of a block with a first estimate of a block check;

determine whether the first estimate of the block check passes or fails; and

provided the first estimate of the block check fails;

turbo decode a received at least one coded parity block to provide an estimate of at least one parity block;

outer decode the first estimate of the at least one sub-block using the estimate of the at least one parity block to provide a second estimate of the at least one sub-block;

concatenate the second estimate of the at least one sub-block to provide a second estimate of the block with a second estimate of the block check; and

determine whether the second estimate of the block check passes or fails.

75. The user terminal of claim 74, wherein each of the received at least one coded sub-block includes a received coded sub-block check, the at least one processor and the modem further configured, in combination, to stop iterations of the turbo decoding based upon the received coded sub-block check for each received at least one coded sub-block.

76. The user terminal of claim 75, the at least one processor and the modem further configured, in combination, to include a cyclic redundancy check applied to the block check when determining whether the first estimate of the block check passes or fails.

77. A user terminal comprising:

means for turbo decoding a received at least one coded sub-block to provide a first estimate of at least one sub-block;

means for concatenating the first estimate of the at least one sub-block to provide a first estimate of a block with a first estimate of a block check;

means for determining whether the first estimate of the block check passes or fails;

means for turbo decoding a received at least one coded parity block to provide an estimate of at least one parity block when the first estimate of the block check fails;

means for outer decoding the first estimate of the at least one sub-block using the estimate of the at least one parity block to provide a second estimate of the at least one sub-block when the first estimate of the block check fails;

means for concatenating the second estimate of the at least one sub-block to provide a second estimate of the block with a second estimate of the block check when the first estimate of the block check fails; and

means for determining whether the second estimate of the block check passes or fails when the first estimate of the block check fails.

78. The user terminal of claim 77, wherein each of the received at least one coded sub-block includes a received coded sub-block check, wherein the means for turbo decoding the received at least one coded sub-block uses the received coded sub-block check for each received at least one coded sub-block to stop iterations of the turbo decoding.

79. The user terminal of claim 78, wherein the means for determining whether the first estimate of the block check passes or fails includes a cyclic redundancy check applied to the block check.

80. A non-transitory computer-readable medium having stored instructions that, when executed by at least one processor in a user terminal, cause the user terminal to perform a method comprising:

turbo decoding a received at least one coded sub-block to provide a first estimate of at least one sub-block;

concatenating the first estimate of the at least one sub-block to provide a first estimate of a block with a first estimate of a block check;

determining whether the first estimate of the block check passes or fails; and

provided the first estimate of the block check fails;

turbo decoding a received at least one coded parity block to provide an estimate of at least one parity block;

outer decoding the first estimate of the at least one sub-block using the estimate of the at least one parity block to provide a second estimate of the at least one sub-block;

concatenating the second estimate of the at least one sub-block to provide a second estimate of the block with a second estimate of the block check; and

determining whether the second estimate of the block check passes or fails.

81. The non-transitory computer-readable medium of claim 80, wherein each of the received at least one coded sub-block includes a received coded sub-block check, the method performed by the user terminal further comprising stopping iterations of the turbo decoding when turbo decoding the received at least one coded sub-block based upon the received coded sub-block check for each received at least one coded sub-block.

82. The non-transitory computer-readable medium of claim 81, wherein the step of determining whether the first estimate of the block check passes or fails comprises a cyclic redundancy check applied to the block check.