Efficient signal transmission methods and apparatus using a shared transmission resource

• US 20060203713A1
• Filed: 03/07/2006
• Published: 09/14/2006
• Est. Priority Date: 05/16/2003
• Status: Active Grant

• Current Assignee: Hui Jin, Junyi Li, Rajiv Laroia, Tom Richardson
• Original Assignee: Qualcomm, Inc.
• Inventors: Laroia, Rajiv, Li, Junyi, Jin, Hui, Richardson, Tom
• Granted Patent: US 8,593,932 B2
• Time in Patent Office: Days
• US Class Current: 370/209
• CPC Class Codes: H04L 25/49 using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems spectral shaping H04L25/03828
• CPC Class Codes: H04L 25/4902 Pulse width modulation; Pulse position modulation
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 5/023 Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601

Abstract

A device includes a zero symbol rate (ZSR) coding/modulation module and a second type coding/modulation module. Both modules generate modulation symbols to be conveyed using the same air link resources but with the non-zero ZSR symbols having a higher power level. The ZSR module generates a mixture of zero and non-zero modulation symbols. A ZSR modulation scheme communicates information using both the position of the non-zero modulation symbols and the phase and/or amplitude of the non-zero modulation symbols. Different ZSR schemes, implementing different ratios relating the number of zero symbols to the total number of symbols, can be associated with different low data rates while second module modulation schemes can be associated with different high data rates. Modulation symbols from two modules are in some embodiments, superimposed. In some embodiments, non-zero ZSR modulation symbols punch out second module modulation symbols which occupy the same air link resource.

Claims

1. A method of transmitting sets of data, the method comprising:

transmitting in a transmission segment including a plurality of minimum transmission units, a first set of data using at least some non-zero modulation symbols and some zero modulation symbols, the first set of data being communicated by a combination of the position of non-zero modulation symbols within the first segment and at least one of phase and amplitude of the transmitted non-zero modulation symbols; and

transmitting in said transmission segment a second set of data using modulation symbols transmitted on at least some of said minimum transmission units used to transmit said first set of data.

2. The method of claim 1, wherein said minimum transmission unit is an OFDM tone-symbol.

3. The method of claim 1, further comprising:

controlling the transmission power levels of non-zero modulation symbols used to communicate said first set of data and modulation symbols used to communicate said second set of data to maintain a minimum power difference.

4. The method of claim 3, wherein said minimum power difference is such that the non-zero modulation symbols used in communicating the first set of data are transmitted at a higher power level than non-zero modulation symbols used to communicate the second set of data.

5. The method of claim 1, wherein transmitting a first set of data includes transmitting information at a first information bit per minimum transmission unit data rate;

and

wherein transmitting a second set of data includes transmitting information at a second information bit per minimum transmission unit data rate, said second information bit per minimum transmission unit data rate being different from the first information bit per minimum transmission unit data rate.

6. The method of claim 5, wherein the second information bit per minimum transmission unit data rate is higher than said first information bit per minimum transmission unit data rate.

7. The method of claim 5, further comprising, prior to said step of transmitting a first set of data:

including in at least a portion of said segment non-zero modulation symbols and zero modulation symbols according to a predetermined zero symbol rate, said modulation symbols which are included according to said predetermined zero symbol rate corresponding to the first set of data.

8. The method of claim 5, further comprising, prior to said step of transmitting a first set of data:

including in at least a portion of said segment non-zero modulation symbols and zero modulation symbols according to one of a plurality of ratios, said ratios indicating predetermined zero symbol rates, said modulation symbols which are included according to one of the plurality of ratios corresponding to the first set of data.

9. The method of claim 8, wherein said one of a plurality of ratios indicates a predetermined zero symbol rate that is greater than or equal to 0.125 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.5.

10. The method of claim 8, wherein if said one of a plurality of ratios is greater than or equal to 0.125, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.5;

and

wherein if said one of a plurality of ratios is greater than or equal to 0.25, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.

11. The method of claim 8, wherein said one of a plurality of ratios is greater than or equal to 0.5 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 0.5.

12. The method of claim 8, wherein said one of a plurality of ratios is greater than or equal to 0.75 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅓

.

13. The method of claim 8, wherein said one of a plurality of ratios is greater than or equal to 0.875 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅙

.

14. The method of claim 8, wherein said transmitting a first set of data includes using QPSK modulation to transmit non-zero symbol values.

15. The method of claim 8, wherein said transmitting a first set of data includes using QPSK modulation to transmit non-zero modulation symbol values;

wherein if said one of a plurality of ratios is greater than or equal to 0.75, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅓

; and

wherein if said one of a plurality of ratios is greater than or equal to 0.875, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅙

.

16. The method of claim 8, further comprising:

partitioning, for use in transmitting said first set of data, said channel segment into a plurality of sub-segments, said portion being one of said sub-segments.

17. The method of claim 16, wherein said segment is not partitioned for use in transmitting said second set of data.

18. The method of claim 8, further comprising, prior to said transmitting the first set of data:

coding information bits included in said first set of data to generate coded information bits;

determining the position of at least one non-zero symbol value in said portion based on the value of at least one of the coded information bits; and

determining at least one of the phase and amplitude of said non-zero modulation symbol based on the value of at least another one of the coded information bits.

19. The method of claim 8, wherein said first set of data includes data having a first priority and data having a second priority, said second priority being lower than said first priority;

wherein said high priority data is communicated through position encoding which includes at least said step of determining the position of at least one non-zero modulation symbol value; and

wherein said low priority data is communicated through phase encoding.

20. The method of claim 1, further comprising, prior to said step of transmitting a first set of data:

including in at least a sub-segment of said segment zero modulation symbols and non-zero modulation symbols according to a ratio, said zero modulation symbols and non-zero modulation symbols which are included according to said ratio corresponding to the first set of data, said ratio being a ratio of positive integers, Nz/Nss, said ratio indicating a fractional proportion of the number of zero modulation symbols in the sub-segment corresponding to the first set of data to the total number of minimum transmission units in said sub-segment.

21. The method of claim 20, wherein said ratio N_Z/N_SS is one of 7/8, 3/4, 5/8, 1/2, 3/8, 1/4 and 1/8.

22. The method of claim 20, wherein the sub-segment size is one of 2, 3, 4, 5, 6, 7, and 8, said sub-segment size indicating the number of minimum transmission units in the sub-segment.

23. The method of claim 20, wherein the sub-segment size is an integer multiple of one of 2, 3, 4, 5, 6, 7, and 8.

24. The method of claim 20, wherein N_SS is a multiple of two;

and

wherein N_Z is an odd number.

25. The method of claim 19, wherein the segment size is an integer multiple of a sub-segment size, said integer multiple being at least 2, said sub-segment size indicating the number of minimum transmission units in the sub-segment.

26. The method of claim 20, further comprising:

including in another sub-segment of said segment non-zero modulation symbols and zero modulation symbols according to a second ratio, said non-zero modulation symbols and non-zero modulation symbols which are included according to said second ratio corresponding to the first set of data, said second ratio being a second ratio of integers, N_Z2/N_SS2, said second ratio indicating a fractional proportion of the number of zero modulation symbols in the second sub-segment corresponding to the first set of data to the total number of minimum transmission units in said second sub-segment, the second ratio being different from the first ratio.

27. The method of claim 1, wherein said segment is a downlink traffic channel segment, the method further comprising, prior to said steps of transmitting in a transmission segment a first set of data and transmitting in a transmission segment a second set of data:

transmitting assignment information indicating a first wireless terminal to which said segment was assigned for use in receiving said first set of data and indicating a second wireless terminal to which said segment was assigned for use in receiving the second set of data.

28. The method of claim 27, wherein said first and second wireless terminals are different, and wherein said method further includes:

selecting said first and second wireless terminals from a plurality of wireless terminals based on information indicative of channel condition quality between a transmitter used to perform said transmitting steps and said first and second wireless terminals, wireless terminals having different channel quality conditions being selected as said first and second wireless terminals.

29. The method of claim 1, further comprising:

combining at least some non-zero modulation symbols corresponding to the first set of data with at least some non-zero modulation symbols corresponding to the second set of data prior to transmitting said first and second sets of data.

30. The method of claim 29, wherein said step of combining includes punching at least some non-zero modulation symbols corresponding to the second set of data with non-zero modulation symbols used to communicate data from said first set of data.

52. The apparatus of claim 51, wherein said combining module includes a punch module for punching at least some non-zero modulation symbols corresponding to the second set of data with non-zero modulation symbols used to communicate data from said first set of data.

31. A communications apparatus, the apparatus comprising:

a first coding and modulation module for processing a first set of data to generate a first set of modulation symbols including information to be communicated in a transmission segment including a plurality of minimum transmission units, the first set of modulation symbols including at least some non-zero modulation symbols and some zero modulation symbols, the first set of data being communicated by a combination of the position of non-zero modulation symbols within the first segment and at least one of phase and amplitude of the transmitted non-zero modulation symbols;

a second coding and modulation module for processing a second set of data to generate a second set of modulation symbols to be transmitted on at least some of said minimum transmission units used to transmit said first set of data; and

a transmission module for transmitting modulation symbols corresponding to said first segment generated by said first and second coding and modulation modules (406, 408).

32. The apparatus of claim 31, wherein said minimum transmission unit is an OFDM tone-symbol.

33. The apparatus of claim 31, further comprising:

a power control module for controlling the transmission power levels of non-zero modulation symbols used to communicate said first set of data and modulation symbols used to communicate said second set of data to maintain a minimum power difference.

34. The apparatus of claim 33, wherein said minimum power difference is such that the non-zero modulation symbols used in communicating the first set of data are transmitted at a higher power level than non-zero modulation symbols used to communicate the second set of data.

35. The apparatus of claim 31, wherein said first coding and modulation module (406) generates the first set of modulation symbols having a first information bit per minimum transmission unit data rate;

and

wherein said second data transmission module generates the second set of modulation symbols having a second information bit per minimum transmission unit data rate, said second information bit per minimum transmission unit data rate being different from the first information bit per minimum transmission unit data rate.

36. The apparatus of claim 35, wherein the second information bit per minimum transmission unit data rate is higher than said first information bit per minimum transmission unit data rate.

37. The apparatus of claim 35, wherein said first coding and modulation module includes a selection module for selecting a zero symbol rate at which said first coding and modulation module is to operate, said selected zero symbol rate being selected from a plurality of zero symbol rate supported by said first coding and modulation module, said zero symbol rate being a ratio of zero modulation symbols to zero modulation symbols and non-zero modulation symbols generated by said first coding and modulation module.

38. The apparatus of claim 37, wherein said selected zero symbol rate is a zero symbol rate greater than or equal to 0.125 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.5.

39. The apparatus of claim 37, wherein if said selected zero symbol rate is greater than or equal to 0.125, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.5;

and

wherein if the selected zero symbol rate is greater than or equal to 0.25, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.

40. The apparatus of claim 37, wherein said selected zero symbol rate is a zero symbol rate greater than or equal to 0.5 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 0.5.

41. The apparatus of claim 37, wherein said selected zero symbol rate is a zero symbol rate greater than or equal to 0.75 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅓

.

42. The apparatus of claim 37, wherein said selected zero symbol rate is a zero symbol rate greater than or equal to 0.875 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅙

.

43. The apparatus of claim 37, wherein said first coding and modulation module includes:

a QPSK modulator for performing modulation corresponding to a first set of data.

44. The apparatus of claim 37, wherein said modulation symbol combining module (410) combines a first set of non-zero QPSK modulation symbols;

wherein if said zero symbol rate is greater than or equal to 0.75, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅓

; and

wherein is said zero symbol rate is greater than or equal to 0.875, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅙

.

45. The apparatus of claim 37, further comprising:

segment partitioning module, said channel segment into a plurality of sub-segments for use in transmitting said first set of data, said portion being one of said sub-segments.

46. The apparatus of claim 37, wherein said segment is not partitioned for use in transmitting said second set of data.

47. The apparatus of claim 45, further comprising,

a first encoder for coding information bits included in said first set of data to generate coded information bits prior to said transmitting the first set of data;

a position determination module for determining the position of at least one non-zero symbol value in said portion based on the value of at least one of the coded information bits; and

a phase determination module for determining the phase of said non-zero modulation symbol based on the value of at least another one of the coded information bits.

48. The apparatus of claim 37, wherein said first set of data includes data having a first priority and data having a second priority, said second priority being lower than said first priority;

wherein said high priority data is communicated through position encoding which includes at least said step of determining the position of at least one non-zero modulation symbol value; and

wherein said low priority data is communicated through phase encoding.

49. The apparatus of claim 31, wherein said segment is a downlink traffic channel segment, the apparatus further comprising:

an assignment transmission module for transmitting assignment information indicating a first wireless terminal to which said segment was assigned for use in receiving said first set of data and indicating a second wireless terminal to which said segment was assigned for use in receiving the second set of data.

50. The apparatus of claim 49, wherein said first and second wireless terminals are different, said apparatus further comprising:

first and second user selection modules for selecting said first and second wireless terminals from a plurality of wireless terminals based on information indicative of channel condition quality between a transmitter used to perform said transmitting steps and said first and second wireless terminals, wireless terminals having different channel quality conditions being selected as said first and second wireless terminals.

51. The apparatus of claim 31, further comprising:

a combining module for combining at least some non-zero modulation symbols corresponding to the first set of data with at least some non-zero modulation symbols corresponding to the second set of data prior to transmitting said first and second sets of data.

53. A communications apparatus, the apparatus comprising:

first coding and modulation means for processing a first set of data to generate a first set of modulation symbols including information to be communicated in a transmission segment including a plurality of minimum transmission units, the first set of modulation symbols including at least some non-zero modulation symbols and some zero modulation symbols, the first set of data being communicated by a combination of the position of non-zero modulation symbols within the first segment and at least one of phase and amplitude of the transmitted non-zero modulation symbols;

second coding and modulation means for processing a second set of data to generate a second set of modulation symbols to be transmitted on at least some of said minimum transmission units used to transmit said first set of data; and

transmission means for transmitting modulation symbols corresponding to said first segment generated by said first and second coding and modulation means.

54. The apparatus of claim 53, wherein said minimum transmission unit is an OFDM tone-symbol.

55. The apparatus of claim 53, further comprising:

means for controlling the transmission power levels of non-zero modulation symbols used to communicate said first set of data and modulation symbols used to communicate said second set of data to maintain a minimum power difference.

56. The apparatus of claim 55, wherein said minimum power difference is such that the non-zero modulation symbols used in communicating the first set of data are transmitted at a higher power level than non-zero modulation symbols used to communicate the second set of data.

57. The apparatus of claim 53, wherein said first coding and modulation means includes means for coding and modulating information at a first information bit per minimum transmission unit data rate;

and

wherein said second coding and modulation means includes means for coding and modulating information at a second information bit per minimum transmission unit data rate, said second information bit per minimum transmission unit data rate being different from the first information bit per minimum transmission unit data rate.

58. The apparatus of claim 57, wherein the second information bit per minimum transmission unit data rate is higher than said first information bit per minimum transmission unit data rate.

59. The apparatus of claim 57, wherein said first coding and modulation means includes a selection means for selecting a zero symbol rate at which said first coding and modulation means is to operate, said selected zero symbol rate being one of a plurality of zero symbol rates supported by said first coding and modulation means, said zero symbol rate being a ratio of zero modulation symbols to zero modulation symbols and non-zero modulation symbols generated by said first coding and modulation means.

60. The apparatus of claim 59, wherein said selected zero symbol rate is a zero symbol rate greater than or equal to 0.125 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.5.

61. The apparatus of claim 59, wherein if said zero symbol rate is greater than or equal to 0.125, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.5;

and

wherein if the zero symbol rate is greater than or equal to 0.25, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 1.

62. The apparatus of claim 59, wherein said selected zero symbol rate is a zero symbol rate greater than or equal to 0.5 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to 0.5.

63. The apparatus of claim 59, wherein said selected zero symbol rate is a zero symbol rate greater than or equal to 0.75 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅓

.

64. The apparatus of claim 59, wherein said selected zero symbol rate is a zero symbol rate greater than or equal to 0.875 when the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅙

.

65. The apparatus of claim 59, wherein said first coding and modulation means includes means for performing QPSK modulation to generate non-zero symbol values.

66. The apparatus of claim 59, wherein said first coding and modulation means includes means for using QPSK modulation to generate non-zero modulation symbol values;

wherein if said selected zero symbol rate is greater than or equal to 0.75, the information bits per minimum transmission unit data rate used to transmit said first set of data is less than or equal to ⅓

; and

wherein if said selected zero symbol rate is greater than or equal to 0.875, the information bits per minimum transmission unit used to transmit said first set of data is less than or equal to ⅙

.

67. The apparatus of claim 59, further comprising:

means for partitioning said channel segment into a plurality of sub-segments for use in transmitting said first set of data, said portion being one of said sub-segments.

68. The apparatus of claim 67, wherein said segment is not partitioned for use in transmitting said second set of data.

69. The apparatus of claim 59, further comprising,

means for coding information bits included in said first set of data to generate coded information bits prior to said transmitting the first set of data;

means for determining the position of at least one non-zero symbol value in said portion based on the value of at least one of the coded information bits; and

means for determining at least one of the phase and amplitude of said non-zero modulation symbol based on the value of at least another one of the coded information bits.

70. The apparatus of claim 69, wherein said first set of data includes data having a first priority and data having a second priority, said second priority being lower than said first priority;

wherein said high priority data is communicated through position encoding; and

wherein said low priority data is communicated through phase encoding.

71. The apparatus of claim 53, wherein said segment is a downlink traffic channel segment, the apparatus further comprising:

means for transmitting assignment information indicating a first wireless terminal to which said segment was assigned for use in receiving said first set of data and indicating a second wireless terminal to which said segment was assigned for use in receiving the second set of data.

72. The apparatus of claim 71, wherein said first and second wireless terminals are different, said apparatus further comprising:

means for selecting said first and second wireless terminals from a plurality of wireless terminals based on information indicative of channel condition quality between a transmitter used to perform said transmitting steps and said first and second wireless terminals, wireless terminals having different channel quality conditions being selected as said first and second wireless terminals.

73. The apparatus of claim 53, further comprising:

means for combining at least some non-zero modulation symbols corresponding to the first set of data with at least some non-zero modulation symbols corresponding to the second set of data prior to transmitting said first and second sets of data.

74. The apparatus of claim 73, wherein said means for combining includes means for punching at least some non-zero modulation symbols corresponding to the second set of data with non-zero modulation symbols used to communicate data from said first set of data.

75. A computer readable medium embodying instructions for controlling apparatus to perform a method of transmitting sets of data, the method comprising:

transmitting in a transmission segment including a plurality of minimum transmission units, a first set of data using at least some non-zero modulation symbols and some zero modulation symbols, the first set of data being communicated by a combination of the position of non-zero modulation symbols within the first segment and at least one of phase and amplitude of the transmitted non-zero modulation symbols; and

transmitting in said transmission segment a second set of data using modulation symbols transmitted on at least some of said minimum transmission units used to transmit said first set of data.

76. The computer readable medium of claim 75, wherein said minimum transmission unit is an OFDM tone-symbol.

77. The computer readable medium of claim 75, further embodying instruction for:

controlling the transmission power levels of non-zero modulation symbols used to communicate said first set of data and modulation symbols used to communicate said second set of data to maintain a minimum power difference.

78. The computer readable medium of claim 77, wherein said minimum power difference is such that the non-zero modulation symbols used in communicating the first set of data are transmitted at a higher power level than non-zero modulation symbols used to communicate the second set of data.

79. The computer readable medium of claim 75, further embodying instructions for:

transmitting information at a first information bit per minimum transmission unit data rate as part of said step of transmitting a first set of data; and

transmitting information at a second information bit per minimum transmission unit data rate as part of said step of transmitting a second set of data, said second information bit per minimum transmission unit data rate being different from the first information bit per minimum transmission unit data rate.