Claims
- 1. A variable data rate Trellis Code Modulation (TCM) encoder comprising:
a variable rate input that receives at least one input bit each symbol period; a Finite State Machine (FSM) receiving two FSM inputs, wherein a first FSM input of the two FSM inputs receives a first input bit of the at least one input but, wherein a second FSM input of the two FSM inputs receives a second input bit of the at least one input bit when present and receives a zero when the second input bit of the at least one input bit is not present, wherein each symbol period the FSM produces an FSM output bit based upon the two FSM inputs; a variable rate symbol mapper operably coupled to the variable rate input and to the FSM, wherein the variable rate symbol mapper, for each symbol period, receives the at least one input bit, the FSM output bit, and a mode selection input that selects a constellation of a plurality of supported constellations including a Quadrature Phase Shift Keying (QPSK) constellation and at least one higher order constellation; wherein at least the FSM output bit is employed to indicate a plurality of valid constellation points of a selected constellation, wherein the plurality of valid constellation points is a subset of all constellation points of the selected constellation; and wherein the variable data rate TCM encoder produces TCM codes with optimal Euclidean distance properties for the QPSK constellation and near optimal Euclidian distance properties for the at least one higher order constellation.
- 2. The variable data rate TCM of claim 1, wherein when the mode selection input selects a QPSK constellation:
the at least one input bit includes only a first input bit; the second FSM input is zero; and the FSM output bit indicates a pair of valid constellation points for the QPSK constellation.
- 3. The variable data rate TCM of claim 2, wherein when the mode selection input selects an 8-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation:
the at least one input bit includes a first input bit and a second input bit; and the FSM output bit and the first input bit indicate a set of valid constellation points for the 8-QAM constellation.
- 4. The variable data rate TCM of claim 2, wherein when the mode selection input selects a 16-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation:
the at least one input bit includes a first input bit, a second input bit, and a third input bit; and the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation.
- 5. The variable data rate TCM of claim 2, wherein when the mode selection input selects a 32-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation:
the at least one input bit includes a first input bit, a second input bit, a third input bit, and a fourth input bit; and the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation.
- 6. The variable data rate TCM of claim 2, wherein when the mode selection input selects a 64-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation:
the at least one input bit includes a first input bit, a second input bit, a third input bit, a fourth input bit, and a fifth input bit; and the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation.
- 7. The variable data rate TCM of claim 1, wherein the variable data rate TCM output is two-dimensional.
- 8. The variable data rate TCM of claim 1, wherein:
the FSM includes a plurality of storage elements and a plurality of modulo-two adders that are intercoupled with one another; the FSM is characterized by a parity check matrix having a set of elements, wherein each element of the set of elements corresponds to a particular coded bit of the set of coded bits; and an element of the set of elements of the parity check matrix corresponding to the FSM output bit includes a plurality of constituent components, wherein at least one constituent component of the plurality of constituent components is identical to an element of the parity check matrix corresponding to a coded bit of the set of coded bits other than the FSM output bit.
- 9. The variable data rate TCM of claim 8, wherein:
the FSM includes three storage elements; and the parity check matrix is: [D2, D, D3+D2+1] or the time-reversed equivalent thereof.
- 10. The variable data rate TCM of claim 9, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 11. The variable data rate TCM of claim 8, wherein:
the FSM includes three storage elements; and the parity check matrix is: [D2, D, D3+D2+D+1] or the time-reversed equivalent thereof.
- 12. The variable data rate TCM of claim 11, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 13. The variable data rate TCM of claim 1, wherein:
the FSM is characterized by a parity check matrix having a set of elements, wherein each element of the set of elements corresponds to a particular coded bit of the set of coded bits; and an element of the set of elements of the parity check matrix corresponding to the FSM output bit includes a plurality of constituent components, wherein at least two constituent components of the plurality of constituent components are identical to elements of the parity check matrix corresponding to respective coded bit of the set of coded bits other than the FSM output bit.
- 14. The variable data rate TCM of claim 13, wherein:
the FSM includes three storage elements; and the parity check matrix is: [D2, D, D3+D2+D+1] or the time-reversed equivalent thereof.
- 15. The variable data rate TCM of claim 14, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 16. The variable data rate TCM of claim 1, wherein:
the FSM includes four storage elements; and the FSM is characterized by a parity check matrix having a set of elements, wherein each element of the set of elements corresponds to a particular coded bit of the set of coded bits and the parity check matrix is: [D3+D2+D, D2, D4+D+1] or the time-reversed equivalent thereof.
- 17. The variable data rate TCM of claim 16, wherein:
the Euclidean distance properties for the QPSK constellation is 7d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 6d2.
- 18. The variable data rate TCM of claim 1, wherein the at least one higher order constellation includes a 16-Quadrature Amplitude Modulated (QAM) constellation, a 32-QAM constellation, and a 64-QAM constellation.
- 19. A variable data rate Trellis Code Modulation (TCM) encoder comprising:
a variable rate input that receives at least one input bit each symbol period; a Finite State Machine (FSM) receiving two FSM inputs, wherein a first FSM input of the two FSM inputs receives a first input bit of the at least one input but, wherein a second FSM input of the two FSM inputs receives a second input bit of the at least one input bit when present and receives a zero when the second input bit of the at least one input bit is not present, wherein each symbol period the FSM produces an FSM output bit based upon the two FSM inputs; a variable rate symbol mapper operably coupled to the variable rate input and to the FSM, wherein the variable rate symbol mapper, for each symbol period, receives the at least one input bit, the FSM output bit, and a mode selection input that selects a constellation of a plurality of supported constellations including a Quadrature Phase Shift Keying (QPSK) constellation and at least one higher order constellation; wherein at least the FSM output bit is employed to indicate a plurality of valid constellation points of a selected constellation, wherein the plurality of valid constellation points is a subset of all constellation points of the selected constellation; and wherein when the mode selection input selects a QPSK constellation, the second input bit is set to zero, the FSM output bit indicates a pair of valid constellation points for the QPSK constellation, and the first input bit selects a constellation point of the pair of valid constellation points as the variable data rate TCM output; and wherein variable data rate TCM encoder produces TCM codes with optimal Euclidean distance properties for the QPSK constellation and near optimal Euclidian distance properties for the at least one higher order constellation.
- 20. The variable data rate TCM of claim 19, wherein when the mode selection input selects an 8-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation:
the at least one input bit includes a first input bit and a second input bit; and the FSM output bit and the first input bit indicate a set of valid constellation points for the 8-QAM constellation.
- 21. The variable data rate TCM of claim 19, wherein when the mode selection input selects a 16-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation:
the at least one input bit includes a first input bit, a second input bit, and a third input bit; and the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation.
- 22. The variable data rate TCM of claim 19, wherein when the mode selection input selects a 32-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation:
the at least one input bit includes a first input bit, a second input bit, a third input bit, and a fourth input bit; and the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation.
- 23. The variable data rate TCM of claim 19, wherein when the mode selection input selects a 64-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation:
the at least one input bit includes a first input bit, a second input bit, a third input bit, a fourth input bit, and a fifth input bit; and the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation.
- 24. A variable data rate Trellis Code Modulation (TCM) encoder comprising:
a variable rate input that receives at least one input bit each symbol period; a Finite State Machine (FSM) receiving two FSM inputs, wherein a first FSM input of the two FSM inputs receives a first input bit of the at least one input but, wherein a second FSM input of the two FSM inputs receives a second input bit of the at least one input bit when present and receives a zero when the second input bit of the at least one input bit is not present, wherein each symbol period the FSM produces an FSM output bit based upon the two FSM inputs; a variable rate symbol mapper operably coupled to the variable rate input and to the FSM, wherein the variable rate symbol mapper, for each symbol period, receives the at least one input bit, the FSM output bit, and a mode selection input that selects a constellation of a plurality of supported constellations including a Quadrature Phase Shift Keying (QPSK) constellation and at least one higher order constellation; wherein at least the FSM output bit is employed to indicate a plurality of valid constellation points of a selected constellation, wherein the plurality of valid constellation points is a subset of all constellation points of the selected constellation; and wherein:
the FSM includes a plurality of storage elements and a plurality of modulo-two adders that are intercoupled with one another; the FSM is characterized by a parity check matrix having a set of elements, wherein each element of the set of elements corresponds to a particular coded bit of the set of coded bits; and an element of the set of elements of the parity check matrix corresponding to the FSM output bit includes a plurality of constituent components, wherein at least one constituent component of the plurality of constituent components is identical to an element of the parity check matrix corresponding to a coded bit of the set of coded bits other than the FSM output bit.
- 25. The variable data rate TCM of claim 24, wherein:
the FSM includes three storage elements; and the parity check matrix is: [D2, D, D3+D2+1] or the time-reversed equivalent thereof.
- 26. The variable data rate TCM of claim 25, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 27. The variable data rate TCM of claim 24, wherein:
the FSM includes three storage elements; and the parity check matrix is: [D2, D, D3+D2+D+1] or the time-reversed equivalent thereof.
- 28. The variable data rate TCM of claim 27, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 29. A variable data rate Trellis Code Modulation (TCM) encoder comprising:
a variable rate input that receives at least one input bit each symbol period; a Finite State Machine (FSM) receiving two FSM inputs, wherein a first FSM input of the two FSM inputs receives a first input bit of the at least one input but, wherein a second FSM input of the two FSM inputs receives a second input bit of the at least one input bit when present and receives a zero when the second input bit of the at least one input bit is not present, wherein each symbol period the FSM produces an FSM output bit based upon the two FSM inputs; a variable rate symbol mapper operably coupled to the variable rate input and to the FSM, wherein the variable rate symbol mapper, for each symbol period, receives the at least one input bit, the FSM output bit, and a mode selection input that selects a constellation of a plurality of supported constellations including a Quadrature Phase Shift Keying (QPSK) constellation and at least one higher order constellation; wherein at least the FSM output bit is employed to indicate a plurality of valid constellation points of a selected constellation, wherein the plurality of valid constellation points is a subset of all constellation points of the selected constellation; and wherein:
the FSM includes four storage elements; and the FSM is characterized by a parity check matrix having a set of elements, wherein each element of the set of elements corresponds to a particular coded bit of the set of coded bits and the parity check matrix is: [D3+D2+D, D2, D4+D+1] or the time-reversed equivalent thereof.
- 30. The variable data rate TCM of claim 29, wherein:
the Euclidean distance properties for the QPSK constellation is 7d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 6d2.
- 31. A wireless communication device comprising:
a Radio Frequency (RF) transceiver; a baseband receiver section operably coupled to the RF transceiver; and a baseband transmitter section operably coupled to the RF transceiver that includes a variable data rate Trellis Code Modulation (TCM) encoder having:
a variable rate input that receives at least one input bit each symbol period; a Finite State Machine (FSM) receiving two FSM inputs, wherein a first FSM input of the two FSM inputs receives a first input bit of the at least one input but, wherein a second FSM input of the two FSM inputs receives a second input bit of the at least one input bit when present and receives a zero when the second input bit of the at least one input bit is not present, wherein each symbol period the FSM produces an FSM output bit based upon the two FSM inputs; a variable rate symbol mapper operably coupled to the variable rate input and to the FSM, wherein the variable rate symbol mapper, for each symbol period, receives the at least one input bit, the FSM output bit, and a mode selection input that selects a constellation of a plurality of supported constellations including a Quadrature Phase Shift Keying (QPSK) constellation and at least one higher order constellation; wherein at least the FSM output bit is employed to indicate a plurality of valid constellation points of a selected constellation, wherein the plurality of valid constellation points is a subset of all constellation points of the selected constellation; and wherein the variable data rate TCM encoder produces TCM codes with optimal Euclidean distance properties for the QPSK constellation and near optimal Euclidian distance properties for the at least one higher order constellation.
- 32. The wireless communication device of claim 31, wherein:
the FSM includes a plurality of storage elements and a plurality of modulo-two adders that are intercoupled with one another; the FSM is characterized by a parity check matrix having a set of elements, wherein each element of the set of elements corresponds to a particular coded bit of the set of coded bits; and an element of the set of elements of the parity check matrix corresponding to the FSM output bit includes a plurality of constituent components, wherein at least one constituent component of the plurality of constituent components is identical to an element of the parity check matrix corresponding to a coded bit of the set of coded bits other than the FSM output bit.
- 33. The wireless communication device of claim 32, wherein:
the FSM includes three storage elements; and the parity check matrix is: [D2, D, D3+D2+1] or the time-reversed equivalent thereof.
- 34. The wireless communication device of claim 33, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 35. The wireless communication device of claim 32, wherein:
the FSM includes three storage elements; and the parity check matrix is: [D2, D, D3+D2+D+1] or the time-reversed equivalent thereof.
- 36. The wireless communication device of claim 35, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 37. The wireless communication device of claim 31, wherein:
the FSM includes four storage elements; and the FSM is characterized by a parity check matrix having a set of elements, wherein each element of the set of elements corresponds to a particular coded bit of the set of coded bits and the parity check matrix is: [D3+D2+D, D2, D4+D+1] or the time-reversed equivalent thereof.
- 38. The wireless communication device of claim 37, wherein:
the Euclidean distance properties for the QPSK constellation is 7d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 6d2.
- 39. The wireless communication device of claim 31, wherein the receiver section further comprises:
a decision feedback equalizer that equalizes incoming signals and produces a plurality of soft decision corresponding to each symbol of a plurality of received symbols; and a variable TCM decoder that receives the plurality of soft decisions and performs TCM decoding operations consistent with the variable data rate TCM to produce output data.
- 40. The wireless communication device of claim 39, wherein the TCM decoder of the receiver section further comprises a FSM that corresponds to the FSM of the TCM of transmitter section.
- 41. A method for Trellis Code Modulating at least one input bit, the method comprising:
receiving at least one input bit each symbol period; encoding, with a Finite State Machine (FSM) each symbol period, a first FSM input and a second FSM input to produce an FSM output bit, wherein the FSM input receives a first input bit of the at least one input but, wherein the second FSM input receives a second input bit of the at least one input bit when present and receives a zero when the second input bit of the at least one input bit is not present; selecting, each symbol period, a constellation of a plurality of supported constellations including a Quadrature Phase Shift Keying (QPSK) constellation and at least one higher order constellation; using at least the FSM output bit to indicate a plurality of valid constellation points of a selected constellation, wherein the plurality of valid constellation points is a subset of all constellation points of the selected constellation; using at least a first input bit of the at least one input bit to select a constellation point of the plurality of valid constellation points as a variable data rate Trellis Code Modulated output; and wherein codes produced have optimal Euclidean distance properties for the QPSK constellation and near optimal Euclidian distance properties for the at least one higher order constellation.
- 42. The method of claim 41, wherein when the QPSK constellation is selected:
the at least one input bit includes only a first input bit; the second FSM input is zero; and the FSM output bit indicates a pair of valid constellation points for the QPSK constellation.
- 43. The method of claim 42, wherein when an 8-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation is selected:
the at least one input bit includes a first input bit and a second input bit; and the FSM output bit and the first input bit indicate a set of valid constellation points for the 8-QAM constellation.
- 44. The method of claim 42, wherein when a 16-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation is selected:
the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation; and a third input bit of the at least one input bit selects a constellation point of the set of valid constellation points as the variable data rate TCM output.
- 45. The method of claim 42, wherein when a 32-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation is selected:
the at least one input bit includes a first input bit, a second input bit, a third input bit, and a fourth input bit; and the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation.
- 46. The method of claim 42, wherein when a 64-Quadrature Amplitude Modulated (QAM) constellation of the at least one higher order constellation is selected:
the at least one input bit includes a first input bit, a second input bit, a third input bit, a fourth input bit, and a fifth input bit; and the FSM output bit, the first input bit, and the second input bit indicate a set of valid constellation points for the 16-QAM constellation.
- 47. The method of claim 41, wherein the variable data rate Trellis Code Modulated output is two-dimensional.
- 48. The method of claim 41, wherein:
the FSM is characterized by a parity check matrix having a set of elements, wherein each element of the set of elements corresponds to a particular coded bit of the set of coded bits; and an element of the set of elements of the parity check matrix corresponding to the FSM output bit includes a plurality of constituent components, wherein at least one constituent component of the plurality of constituent components is identical to an element of the parity check matrix corresponding to a coded bit of the set of coded bits other than the FSM output bit.
- 49. The method of claim 48, wherein the parity check matrix is: [D2, D, D3+D2+1] or the time-reversed equivalent thereof.
- 50. The method of claim 49, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 51. The method of claim 48, wherein the parity check matrix is: [D2, D, D3+D2+D+1] or the time-reversed equivalent thereof.
- 52. The method of claim 51, wherein:
the Euclidean distance properties for the QPSK constellation is 6d2 where d is the distance between constellation points; and the Euclidian distance properties for the at least one higher order constellation is 5d2.
- 53. The method of claim 41, wherein the at least one higher order constellation includes a 16-Quadrature Amplitude Modulated (QAM) constellation, a 32-QAM constellation, and a 64-QAM constellation.
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application Serial No. 60/328,049, filed Oct. 9, 2001, which is incorporated herein by reference in its entirety.
Provisional Applications (1)
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Number |
Date |
Country |
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60328049 |
Oct 2001 |
US |