Adaptive coding and modulation

• US 20020183020A1
• Filed: 06/04/2002
• Published: 12/05/2002
• Est. Priority Date: 06/05/2001
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Tong, Wen, Zhu, Peiying, Royer, Claude C.
• Granted Patent: US 7,043,210 B2
• Time in Patent Office: Days
• US Class Current: 455/108
• 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 1/0068 by puncturing
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 27/0012 arrangements for identifying the type of modulation

Abstract

The present invention provides a unique feedback system in a wireless communication system wherein the transmission channel is always overloaded with data, which is configured and modulated at a select order of modulation. Based on the channel conditions, only a portion of the data can be successfully received. As such, the receiver will attempt to receive the data using demodulation techniques corresponding to the different levels of modulation used to encode the data transmitted. The receiver will determine the data that is recovered, or the highest order of modulation at which the data is recovered, and provide feedback to the transmitter. The transmitter will then retransmit the data that was not properly received. By overloading the channel at all times, the maximum amount of data capable of being transmitted over the channel is optimized without requiring or heavily relying on the receiver feeding back channel condition information to the transmitter.

Claims

1. A method for facilitating communication with a mobile terminal comprising:

a) associating a plurality of groups of data with a corresponding plurality of modulation orders to form data wherein more significant groups of data are associated with lower modulation orders and less significant groups of data are associated with higher modulation orders;

b) transmitting the data using a highest order of modulation;

c) receiving feedback from the mobile terminal indicative of the data not received by the mobile terminal;

d) identifying the data not received based on the feedback; and

e) retransmitting the data not received.

2. The method of claim 1 wherein the modulation is quadrature amplitude modulation.

3. The method of claim 2 wherein the plurality of orders of modulation range from quadrature phase shift keying to 2ⁿ quadrature amplitude modulation.

4. The method of claim 1 wherein each of the plurality of groups of data is associated with a unique packet scheduled for transmission and the lower modulation orders are for those packets having a higher priority.

5. The method of claim 1 wherein the feedback is provided according to an automated retransmission request protocol.

6. The method of claim 1 wherein the feedback is provided according to a hybrid automated retransmission request protocol.

7. The method of claim 1 wherein the feedback is indicative of those of the plurality of modulation orders that were not recoverable.

8. The method of claim 1 wherein the feedback is indicative of those of the plurality of modulation orders that were recoverable.

9. The method of claim 1 wherein the feedback is indicative of those of the groups of data that were recoverable.

10. The method of claim 1 wherein the feedback is indicative of those of the groups of data that were not recoverable.

11. The method of claim 1 wherein the data retransmitted is punctured into the data being transmitted.

12. The method of claim 1 further comprising controlling the highest of the plurality of modulation orders based on the feedback.

14. The method of claim 13 wherein the modulation is quadrature amplitude modulation.

15. The method of claim 14 wherein the plurality of orders of modulation range from quadrature phase shift keying to 2ⁿ quadrature amplitude modulation.

16. The method of claim 13 wherein each of the plurality of groups of data is associated with a unique packet scheduled for transmission and the lower modulation orders are for those packets having a higher priority.

17. The method of claim 13 wherein the feedback is provided according to an automated retransmission request protocol.

18. The method of claim 13 wherein the feedback is provided according to a hybrid automated retransmission request protocol.

19. The method of claim 13 wherein the feedback is indicative of those of the plurality of modulation orders that were not recoverable.

20. The method of claim 13 wherein the feedback is indicative of those of the plurality of modulation orders that were recoverable.

21. The method of claim 13 wherein the feedback is indicative of those of the groups of data that were recoverable.

22. The method of claim 13 wherein the feedback is indicative of those of the groups of data that were not recoverable.

23. The method of claim 13 further comprising determining the highest of the plurality of modulation orders based on historical performance and transmitting information indicative of the highest of the plurality of modulation orders to the base station.

25. The apparatus of claim 24 wherein the modulation is quadrature amplitude modulation.

26. The apparatus of claim 25 wherein the plurality of orders of modulation range from quadrature phase shift keying to 2ⁿ quadrature amplitude modulation.

27. The apparatus of claim 24 wherein each of the plurality of groups of data is associated with a unique packet scheduled for transmission and the lower modulation orders are for those packets having a higher priority.

28. The apparatus of claim 24 wherein the feedback is provided according to an automated retransmission request protocol.

29. The apparatus of claim 24 wherein the feedback is provided according to a hybrid automated retransmission request protocol.

30. The apparatus of claim 24 wherein the feedback is indicative of those of the plurality of modulation orders that were not recoverable.

31. The apparatus of claim 24 wherein the feedback is indicative of those of the plurality of modulation orders that were recoverable.

32. The apparatus of claim 24 wherein the feedback is indicative of those of the groups of data that were recoverable.

33. The apparatus of claim 24 wherein the feedback is indicative of those of the groups of data that were not recoverable.

34. The apparatus of claim 24 wherein the data retransmitted is punctured into the data being transmitted.

35. The apparatus of claim 24 wherein the control system is further adapted to control the highest of the plurality of modulation orders based on the feedback.

37. The apparatus of claim 36 wherein the modulation is quadrature amplitude modulation.

38. The apparatus of claim 37 wherein the plurality of orders of modulation range from quadrature phase shift keying to 2ⁿ quadrature amplitude modulation.

39. The apparatus of claim 36 wherein each of the plurality of groups of data is associated with a unique packet scheduled for transmission and the lower modulation orders are for those packets having a higher priority.

40. The apparatus of claim 36 wherein the feedback is provided according to an automated retransmission request protocol.

41. The apparatus of claim 36 wherein the feedback is provided according to a hybrid automated retransmission request protocol.

42. The apparatus of claim 36 wherein the feedback is indicative of those of the plurality of modulation orders that were not recoverable.

43. The apparatus of claim 36 wherein the feedback is indicative of those of the plurality of modulation orders that were recoverable.

44. The apparatus of claim 36 wherein the feedback is indicative of those of the groups of data that were recoverable.

45. The apparatus of claim 36 wherein the feedback is indicative of those of the groups of data that were not recoverable.

46. The apparatus of claim 36 further comprising determining the highest of the plurality of modulation orders based on historical performance and transmitting information indicative of the highest of the plurality of modulation orders to the base station.

13. A method for facilitating communication with a base station wherein the base station associates a plurality of groups of data with a corresponding plurality of modulation orders to form data wherein more significant groups of data are associated with lower modulation orders and less significant groups of data are associated with higher modulation orders and transmits the data using a highest order of modulation, the method comprising:

a) attempting to receive the data at each of the plurality of modulation orders;

b) generating feedback indicative of the data not received; and

c) transmitting the feedback to the base station to allow the base station to identify the data not received based on the feedback and retransmit the data not received.

24. An apparatus for facilitating communication with a mobile terminal comprising control circuitry, receive circuitry and transmit circuitry cooperatively adapted to:

a) associate a plurality of groups of data with a corresponding plurality of modulation orders to form data wherein more significant groups of data are associated with lower modulation orders and less significant groups of data are associated with higher modulation orders;

b) transmit the data using a highest order of modulation;

c) receive feedback from the mobile terminal indicative of the data not received by the mobile terminal;

d) identify the data not received based on the feedback; and

e) retransmit the data not received.

36. An apparatus for facilitating communication with a base station wherein the base station associates a plurality of groups of data with a corresponding plurality of modulation orders to form data wherein more significant groups of data are associated with lower modulation orders and less significant groups of data are associated with higher modulation orders and transmits the data using a highest order of modulation, the apparatus comprising control circuitry, receive circuitry and transmit circuitry cooperatively adapted to:

a) attempt to receive the data at each of the plurality of modulation orders;

b) generate feedback indicative of the data not received; and

c) transmit the feedback to the base station to allow the base station to identify the data not received based on the feedback and retransmit the data not received.