METHOD AND APPARATUS FOR SUB-SLOT PACKETS IN WIRELESS COMMUNICATION

• US 20070195740A1
• Filed: 02/20/2007
• Published: 08/23/2007
• Est. Priority Date: 02/21/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Bhushan, Naga, Wei, Yongbin, Kadous, Tamer, Fan, Mingxi
• Granted Patent: US 9,461,736 B2
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 7/2656 for structure of frame, burst
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0007 by modifying the frame length
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0016 Time-frequency-code
• CPC Class Codes: H04L 5/0028 Variable division signaling therefor H04L5/0092
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

Techniques for efficiently sending and receiving data in a wireless communication system are described herein. The techniques utilize a slot structure that is backward compatible with existing design. The techniques include sending and receiving forward link packets that occupy less than a full slot of the slot structure. An output waveform, which includes at least one slot, is generated at an access point. Each slot is segmented into two half-slots, wherein at least one half-slot includes a data unit of a packet. At a terminal, the output waveform is received and processed to extract the data unit and the data unit is processed to determine whether it is accurate. The terminal also generates ACK/NACK information in response to the results of processing the data unit and transmits channel information including the ACK/NACK information. The access point interprets the ACK/NACK information to determine if the data unit should be resent.

Claims

1. An apparatus, comprising:

a receiver to receive channel information from a remote station the channel information including ACK/NACK (acknowledgement/negative acknowledgement) information;

at least one processor configured to;

generate an output waveform comprising at least one slot, each slot segmented into two half-slots, wherein at least one half-slot includes a data unit of a packet; and

interpret the ACK/NACK information to determine if the data unit should be resent to the remote station;

a memory coupled to the at least one processor; and

a transmitter configured for transmitting the output waveform.

2. The apparatus of claim 1, wherein the output waveform further comprises at least one additional slot wherein the at least one additional slot contains another data unit selected from the group consisting of:

from the packet and configured for a full slot, from another packet and configured for a half-slot, and from another packet and configured for a full slot.

3. The apparatus of claim 1, wherein the output waveform is further configured as eight interleaves of half-slots, four interleaves of full slots, or combinations thereof.

4. The apparatus of claim 1, wherein:

the channel information further comprises data rate control information; and

the at least one processor is further configured to select a first modulation for the data unit responsive to the data rate control information.

5. The apparatus of claim 1, wherein:

the at least one processor is further configured to generate the output waveform with a modulation correlated to a payload size for the data unit.

6. The apparatus of claim 1, wherein:

the at least one processor is further configured to generate a new output waveform with a different modulation of the data unit if the ACK/NACK information indicates that the data unit should be resent; and

the transmitter is further configured for transmitting the new output waveform.

7. The apparatus of claim 6, wherein the different modulation of the new output waveform is selected to be at a lower data rate than a modulation of the output waveform.

8. The apparatus of claim 6, wherein the different modulation is selected from the group consisting of quadrature phase shift keying, 8-phase shift keying, 16-quadrature amplitude modulation and 64-quadrature amplitude modulation.

9. The apparatus of claim 1, wherein:

the channel information further comprises a channel quality indicator;

the at least one processor is further configured to;

interpret the channel quality indicator; and

generate a new output waveform with a different modulation for subsequent data units responsive to the interpreted channel quality indicator; and

the transmitter is further configured for transmitting the new output waveform.

10. The apparatus of claim 9, wherein the different modulation is selected from the group consisting of quadrature phase shift keying, 8-phase shift keying, 16-quadrature amplitude modulation and 64-quadrature amplitude modulation.

11. The apparatus of claim 1, wherein the at least one processor is further configured to:

select code division multiplexing (CDM) or orthogonal frequency division multiplexing (OFDM) for each of at least one traffic segment in each half-slot; and

generate an output waveform comprised of the at least one traffic segment, each traffic segment carrying CDM data if CDM is selected for the traffic segment or OFDM data if OFDM is selected for the traffic segment.

12. The apparatus of claim 11, wherein the at least one processor is further configured to:

select CDM or OFDM for each of first and second traffic segments; and

generate the output waveform comprised of the first and second traffic segments and an overhead segment, each of the first and second traffic segments carrying CDM data or OFDM data, and the overhead segment carrying overhead data.

13. The apparatus of claim 11, wherein the at least one processor is further configured to:

select CDM or OFDM for each of multiple traffic segments for multiple carriers; and

generates the output waveform comprised of the multiple traffic segments for the multiple carriers, each traffic segment carrying CDM data or OFDM data.

14. The apparatus of claim 11, wherein the at least one processor is further configured to:

generate a first waveform comprised of traffic segments carrying CDM data;

generate a second waveform comprised of traffic segments carrying OFDM data; and

generate the output waveform based on the first and second waveforms.

15. An apparatus, comprising:

at least one processor to;

process an input waveform comprising at least one slot, each slot segmented into two half-slots, wherein at least one half-slot includes a data unit of a packet;

process the data unit to determine whether the data unit is accurate; and

generate ACK/NACK (acknowledgement/negative acknowledgement) information responsive to the result of processing the data unit;

a memory coupled to the at least one processor; and

a transmitter for transmitting channel information comprising the ACK/NACK information.

16. The apparatus of claim 15, wherein the input waveform further comprises at least one additional slot wherein the at least one additional slot contains another data unit selected from the group consisting of:

from the packet and configured for a full slot, from another packet and configured for a half-slot, and from another packet and configured for a full slot.

17. The apparatus of claim 15, wherein the input waveform is further configured as eight interleaves of half-slots, four interleaves of full slots, or combinations thereof.

18. The apparatus of claim 15, wherein the at least one processor is further configured to:

generate data rate control information; and

include the data rate control information in the channel information.

19. The apparatus of claim 15, wherein the at least one processor is further configured to:

analyze received signal quality and generate a channel quality indicator responsive to the received signal quality; and

include the channel quality indicator in the channel information.

20. The apparatus of claim 15, wherein the at least one processor is further configured to process the data unit using a modulation selected from the group consisting of quadrature phase shift keying, 8-phase shift keying, 16-quadrature amplitude modulation and 64-quadrature amplitude modulation.

21. The apparatus of claim 15, wherein the at least one processor is further configured to:

determine whether code division multiplexing (CDM) or orthogonal frequency division multiplexing (OFDM) is used for at least one traffic segment in each half-slot;

process received samples to recover CDM data sent in the traffic segment if CDM is used; and

process the received samples to recover OFDM data sent in the traffic segment if OFDM is used.

22. The apparatus of claim 21, wherein the at least one processor is further configured to:

process the received samples to obtain received symbols for subcarriers used for the traffic segment; and

process the received symbols to recover the OFDM data sent in the traffic segment.

23. The apparatus of claim 21, wherein the at least one processor is further configured to:

filter the received samples to obtain filtered samples for subcarriers used for the traffic segment;

process the filtered samples to obtain input samples for the traffic segment;

decover the input samples with multiple orthogonal codes to obtain received symbols; and

process the received symbols to recover the CDM data sent in the traffic segment.

24. The apparatus of claim 21, wherein the at least one processor is further configured to:

process the received samples to obtain frequency-domain symbols for a plurality of subcarriers;

process the frequency-domain symbols for subcarriers used for the traffic segment to obtain time-domain samples;

decover the time-domain samples with multiple orthogonal codes to obtain received symbols; and

process the received symbols to recover the CDM data sent in the traffic segment.

25. A communication system, comprising:

at least one access point, comprising;

an access point receiver to receive channel information including ACK/NACK (acknowledgement/negative acknowledgement) information;

at least one access point processor to;

generate an output waveform comprising at least one slot, each slot segmented into two half-slots, wherein at least one half-slot includes a data unit of a packet; and

interpret the ACK/NACK information to determine if the data unit should be resent;

an access point memory coupled to the at least one access point processor; and

an access point transmitter for transmitting the output waveform; and

at least one terminal, comprising;

a terminal receiver to receive the output waveform;

at least one terminal processor to;

 

process the output waveform comprising at least one slot, each slot segmented into two half-slots, wherein at least one half-slot includes a data unit of a packet;

 

process the data unit to determine whether the data unit is accurate; and

 

generate ACK/NACK (acknowledgement/negative acknowledgement) information responsive to the result of processing the data unit;

a terminal memory coupled to the at least one terminal processor; and

a terminal transmitter for transmitting the channel information comprising the ACK/NACK information.

26. The communication system of claim 25, wherein the output waveform further comprises at least one additional slot wherein the at least one additional slot contains another data unit selected from the group consisting of:

from the packet and configured for a full slot, from another packet and configured for a half-slot, and from another packet and configured for a full slot.

27. The communication system of claim 25, wherein the output waveform is further configured as eight interleaves of half-slots, four interleaves of full slots, or combinations thereof.

28. The communication system of claim 25, wherein:

the channel information further comprises data rate control information; and

the at least one access point processor is further configured to select a first modulation for the data unit responsive to the data rate control information.

29. The apparatus of claim 25, wherein:

the at least one access point processor is further configured to generate the output waveform with a modulation correlated to a payload size for the data unit.

30. The communication system of claim 25, wherein:

the at least one access point processor is further configured to generate a new output waveform with a different modulation of the data unit if the ACK/NACK information indicates that the data unit should be resent; and

the transmitter is further configured for transmitting the new output waveform.

31. The apparatus of claim 30, wherein the different modulation of the new output waveform is selected to be at a lower data rate than a modulation of the output waveform.

32. The communication system of claim 30, wherein the different modulation is selected from the group consisting of quadrature phase shift keying, 8-phase shift keying, 16-quadrature amplitude modulation and 64-quadrature amplitude modulation.

33. The communication system of claim 25, wherein:

the channel information further comprises a channel quality indicator;

the at least one access point processor is further configured to;

interpret the channel quality indicator; and

generate a new output waveform with a different modulation for subsequent data units responsive to the interpreted channel quality indicator; and

the transmitter is further configured for transmitting the new output waveform.

34. The communication system of claim 33, wherein the different modulation is selected from the group consisting of quadrature phase shift keying, 8-phase shift keying, 16-quadrature amplitude modulation and 64-quadrature amplitude modulation.

35. The communication system of claim 25, wherein the at least one access point processor is further configured to:

select code division multiplexing (CDM) or orthogonal frequency division multiplexing (OFDM) for each of at least one traffic segment in each half-slot; and

generate an output waveform comprised of the at least one traffic segment, each traffic segment carrying CDM data if CDM is selected for the traffic segment or OFDM data if OFDM is selected for the traffic segment.

36. The communication system of claim 35, wherein the at least one access point processor is further configured to:

select CDM or OFDM for each of first and second traffic segments; and

generate the output waveform comprised of the first and second traffic segments and an overhead segment, each of the first and second traffic segments carrying CDM data or OFDM data, and the overhead segment carrying overhead data.

37. The communication system of claim 35, wherein the at least one access point processor is further configured to:

select CDM or OFDM for each of multiple traffic segments for multiple carriers; and

generates the output waveform comprised of the multiple traffic segments for the multiple carriers, each traffic segment carrying CDM data or OFDM data.

38. The communication system of claim 35, wherein the at least one access point processor is further configured to:

generate a first waveform comprised of traffic segments carrying CDM data;

generate a second waveform comprised of traffic segments carrying OFDM data; and

generate the output waveform based on the first and second waveforms.

39. A method in a communication system, comprising:

generating an output waveform at an access point, the output waveform comprising at least one slot, each slot segmented into two half-slots, wherein at least one half-slot includes a data unit of a packet;

at a terminal;

processing the output waveform to extract the data unit;

processing the data unit to determine whether the data unit is accurate; and

generating ACK/NACK (acknowledgement/negative acknowledgement) information responsive to processing the data unit; and

transmitting channel information comprising the ACK/NACK information;

interpreting the ACK/NACK information at the access point to determine if the data unit should be resent.

40. The communication system of claim 39, wherein the output waveform is further generated to include at least one additional slot wherein the at least one additional slot contains another data unit selected from the group consisting of:

from the packet and configured for a full slot, from another packet and configured for a half-slot, and from another packet and configured for a full slot.

41. The communication system of claim 39, wherein the output waveform is further generated as eight interleaves of half-slots, four interleaves of full slots, or combinations thereof.

42. The method of claim 39, further comprising selecting a first modulation for the data unit responsive to data rate control information included in the channel information.

43. The apparatus of claim 39, the output waveform is further generated with a modulation correlated to a payload size for the data unit.

44. The method of claim 39, further comprising:

generating a new output waveform with a different modulation of the data unit if the ACK/NACK information indicates that the data unit should be resent; and

transmitting the new output waveform.

45. The apparatus of claim 44, wherein the different modulation of the new output waveform is selected to be at a lower data rate than a modulation of the output waveform.

46. The method of claim 44, wherein the different modulation is selected from the group consisting of quadrature phase shift keying, 8-phase shift keying, 16-quadrature amplitude modulation and 64-quadrature amplitude modulation.

47. The method of claim 39, further comprising:

interpreting a channel quality indicator included in the channel information;

generating a new output waveform with a different modulation for subsequent data units responsive to the interpreting; and

transmitting the new output waveform.

48. The method of claim 47, wherein the different modulation is selected from the group consisting of quadrature phase shift keying, 8-phase shift keying, 16-quadrature amplitude modulation and 64-quadrature amplitude modulation.

49. The method of claim 39, further comprising:

selecting code division multiplexing (CDM) or orthogonal frequency division multiplexing (OFDM) for each of at least one traffic segment in each half-slot; and

generating an output waveform comprised of the at least one traffic segment, each traffic segment carrying CDM data if CDM is selected for the traffic segment or OFDM data if OFDM is selected for the traffic segment.

50. The method of claim 49, further comprising:

selecting CDM or OFDM for each of first and second traffic segments; and

generating the output waveform comprised of the first and second traffic segments and an overhead segment, each of the first and second traffic segments carrying CDM data or OFDM data, and the overhead segment carrying overhead data.

51. The method of claim 49, further comprising:

selecting CDM or OFDM for each of multiple traffic segments for multiple carriers; and

generating the output waveform comprised of the multiple traffic segments for the multiple carriers, each traffic segment carrying CDM data or OFDM data.

52. The method of claim 49, further comprising:

generating a first waveform comprised of traffic segments carrying CDM data;

generating a second waveform comprised of traffic segments carrying OFDM data; and

generating the output waveform based on the first and second waveforms.