Shared channel structure, ARQ systems and methods

• US 20030067899A9
• Filed: 10/24/2001
• Published: 04/10/2003
• Est. Priority Date: 10/24/2000
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Islam, Mohammad Khaledul, Guo, Ning, Ren, Hong, Chen, Xixian, Li, Litong, McGowan, Neil N.
• Granted Patent: US 7,154,846 B2
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 1/7073 Synchronisation aspects
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04B 7/2618 using hybrid code-time division multiple access [CDMA-TDMA]
• CPC Class Codes: H04B 7/2637 for logical channel control
• CPC Class Codes: H04J 13/0048 Walsh
• 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 1/0014 by adapting the source coding
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0029 Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling power control H04W52/04
• CPC Class Codes: H04L 1/0046 Code rate detection or code type detection H04L1/0038 takes precedence; detection of the data rate H04L25/0262; for packet format H04L1/0091
• CPC Class Codes: H04L 1/0068 by puncturing
• CPC Class Codes: H04L 1/0072 Error control for data other than payload data, e.g. control data
• CPC Class Codes: H04L 1/0073 Special arrangements for feedback channel
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/1607 Details of the supervisory signal
• CPC Class Codes: H04L 1/1809 Selective-repeat protocols
• CPC Class Codes: H04L 2001/125 Arrangements for preventing errors in the return channel
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/16 : Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/58 : Format of the TPC bits
• CPC Class Codes: H04W 72/12 : Wireless traffic scheduling
• CPC Class Codes: H04W 72/23 : in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/00 : Wireless channel access
• CPC Class Codes: H04W 74/04 : Scheduled access hybrid access H04W74/02

Abstract

A forward link design is provided employing CDMA (code division multiple access) technologies in which time division multiplexing is employed between data and control information on the forward link to service multiple users per slot. Another forward link design employing CDMA (code division multiple access) technologies is provided in which code division multiplexing between data and control information is employed on the forward link to service multiple users per slot, which is preferably backwards compatible with legacy standards such as IS2000A. A reverse link design is also provided.

Claims

1. A method of transmitting over a forward link in a CDMA (code division multiple access) communications system, the method comprising:

transmitting forward link frames, each frame comprising a plurality of slots;

for each slot, transmitting a forward shared channel, the forward shared channel being adapted to have up to a predetermined maximum number of Walsh covers, and the forward shared channel being scheduled slot-wise to carry in some slots content for a single high-rate data user, in some slots content for a plurality of voice users (a voice user being voice or low-rate data);

transmitting a user identification channel adapted to allow users to determine which slots contain their content.

2. A method according to claim 1 wherein the forward shared channel is further adapted to have scheduled in some slots content for a plurality of voice users and a single high-rate data users.

3. A method according to claim 2 wherein the user identification channel is transmitted in parallel with the shared channel using a different code space.

4. A method according to claim 3 wherein during each slot the forward shared channel is scheduled over a number of Walsh covers equal to the predetermined maximum number of Walsh covers minus a number of Walsh covers necessary to accommodate legacy users being serviced during the slot.

5. A method according to claim 4 wherein the predetermined maximum number of Walsh covers is 14 16-ary Walsh covers.

6. A method according to claim 3 wherein the Walsh covers are 16-ary Walsh covers and in a given slot, one or more of the 16-ary Walsh covers is further sub-divided for the plurality of voice users, with all remaining 16-ary Walsh covers of the forward shared channel being assigned to a shared data channel which is made available to a single high-rate data user at a time.

7. A method according to claim 6 wherein each slot has a 1.25 ms slot duration, with the shared data channel content for a given user may occupy multiple contiguous slots.

8. A method according to claim 7 further comprising transmitting control information in respect of the shared data channel.

9. A method according to claim 8 wherein the control information in respect of the shared data channel comprises an indication of a number of contiguous slots to be made available to a given data user.

10. A method according to claim 9 wherein the control information comprises a data packet size and single/hybrid slot indicator for low order modulation (QPSK and 8-PSK) and data packet size, single/hybrid slot indicator, and gain value for 64QAM and 16QAM shared channel data for high order modulation.

11. A method according to claim 3 wherein at least some of the slots contain voice transmitted at full rate.

12. A method according to claim 11 further comprising turbo encoding the voice to be transmitted at full rate and transmitting such content using one or two shared channel 16-ary Walsh codes.

13. A method according to claim 3 wherein at least some of the slots contain voice content transmitted using half, quarter or eighth rate.

14. A method according to claim 11 further comprising encoding half, quarter and eighth rate voice channels using convolutional coding and transmitting such content using only one shared channel 16-ary Walsh code.

15. A method according to claim 3 wherein frames have a 20 ms duration, with each frame consisting of sixteen 1.25 ms slots, and each slot containing 1536 chips.

16. A method according to claim 3 wherein the user identification channel is used to inform a particular user whether a current slot of the shared data channel contains data for the user by transmitting a user identifier comprising a Walsh code and a sub-identifier.

17. A method according to claim 16 wherein the sub-identifier is an N bit identifier, and the Walsh code is one of P M-ary Walsh codes.

18. A method according to claim 17 wherein the user identification channel is transmitted in K chip slots, and has I and Q channels, thereby providing the 2*K/(M) bit capacity, and the ability to transmit 2*K*M/N user identifiers per slot.

19. A method according to claim 16 wherein M=512, K=1536, N=3 and P=16 thereby providing the ability to transmit 32 user identifiers per slot, and the ability to uniquely identify 128 different users.

20. A method according to claim 16 wherein M=512, K=1536, N=3 and P=8 thereby providing the ability to transmit 16 user identifiers per slot, and the ability to uniquely identify 64 different users.

21. A method according to claim 15 wherein a voice only user is assigned a single user identifier, and a user with voice and data is assigned one user identifier for data and one user identifier for voice.

22. A method according to claim 1 wherein for a given slot during which high-rate data is to be transmitted, data is transmitted for a high-rate data user likely to have good channel conditions during the slot.

23. A method according to claim 22 further comprising performing adaptive modulation and coding for the shared data channel based on channel estimates fed back every slot.

24. A method according to claim 3 further comprising coding voice content in one of five possible ways depending upon rate and channel estimate as follows:

full rate voice uses Turbo coding and can use either one or two shared channel 16-ary-Walsh codes with 8PSK modulation with one shared channel 16-ary Walsh code or QPSK modulation with two shared channel 16-ary Walsh codes;

half, quarter and eighth rate voice uses convolutional coding and uses only one shared channel 16-ary Walsh code.

25. A method according to claim 1 further adapted to schedule voice users by:

giving preference to schedule voice users in a first half frame;

for each slot, looking for an ACK or NAK VARQ signal from each voice user scheduled during the slot and where possible rescheduling in the second half frame voice users from which a NAK VARQ signal is received.

26. A method according to claim 25 wherein the VARQ signals are received on a 1×

RTT-like reverse pilot channel in place of predetermined former power control bit locations.

27. A method according to claim 26 wherein reverse rate indicator (RRI) signals are also received on the 1×

RTTT-like reverse pilot channel in place of predetermined former power control bit locations.

28. A method according to claim 27 wherein each frame has 16 slots and the positions of the VARQ and RRI signals obey the following rules:

for users with voice service only, the VARQ valid bit positions are in slots 3, 4, 7, 8, 9, 11, 12, 13 and 15 of a current frame and slots 0 and 1 of a following frame, and slots 2, 6, 10 and 14 are reserved for the RRI;

for a user with both data and voice services, the RRI is transmitted in slots 0 to 8 and 11 to 15 and the VARQ is transmitted in slots 9 and 10.

29. A method according to claim 28 wherein if a user'"'"'s voice data in a given slot is decoded correctly, the ACK VARQ signal will be sent to the base station in all the slots in the frame following the given slot and in the first two slots of a following frame, and if no voice was transmitted for the user in a given slot, or if the user'"'"'s voice data is decoded incorrectly, then a NAK VARQ signal will be sent on all slots until a slot containing the user'"'"'s voice data is correctly decoded.

30. A method according to claim 1 further comprising:

processing a reverse channel for each voice user scheduled during a given slot, and looking for a NAK VARQ signal or an ACK VARQ signal in predetermined slot positions in the reverse channel relative to the given slot.

31. A method according to claim 1 further comprising transmitting a forward supplemental paging channel, the forward supplemental paging channel broadcasting a number of 16-ary Walsh codes available for shared channel slots and a number of 16-ary Walsh codes available for voice in hybrid shared channel slots.

32. A method according to claim 1 further receiving channel estimates from each user.

33. A method according to claim 32 wherein for each user, adaptive modulation and coding is performed on the basis of the channel estimates received for that user, and scheduling of users in each slot is also performed on the basis of the channel estimates.

34. A method according to claim 33 further comprising receiving sector select values from each user.

35. A method according to claim 34 wherein the channel estimates and sector select values are received on a Channel Estimate and Sector Selector (R-CHESS) channel from each user.

36. A method according to claim 35 wherein the sector select value for a given user identifies a best sector for the given user and handoffs are performed for the given user on the basis of the sector selector values received from that user.

37. A method according to claim 36 wherein:

each sector selector value is used to indicate the sector that the wireless terminal thinks it should be operating;

each sector select value indicates a sector belonging to an active set, the active set being sectors previously identified to have an acceptable signal strength;

for reverse link traffic, all sectors in the active set listen to transmissions from the wireless terminal with a best of multiple signals received by multiple sectors being selected as the receive signal thereby providing a soft reverse link handoff mechanism;

for forward link traffic, only the sector defined by the sector select value for a given user transmits to the given user.

38. A method according to claim 36 wherein for data or data/voice users, the sector select value is not allowed to change from one sector value directly to another sector value, the sector select value only being allowed to change from a sector value to the null value then to a sector value, and wherein for voice only users, the sector select value is allowed to change directly from one sector value to another sector value.

40. A method according to claim 35 further comprising:

in the event a sector select erasure is received in a current active sector, if the sector select erasure is received corresponding to a data user then no data will be scheduled for that user, and the sector select erasure is received corresponding to a voice user then voice content will continue to be scheduled for that user.

41. A method according to claim 38 further comprising:

requiring two sector select values corresponding to another valid sector to be received before the current active sector stops sending voice content.

42. A method according to claim 1 further comprising providing systematic predetermined incremental redundancy symbol selection for voice and data on the shared channel by:

using an even second timing referenced to UTC (Universal Coordinated Time) to select a portion of turbo coded data symbols to be sent in a given slot;

using a count value k which starts on each even second which counts from k=0 to Kmax incrementing every (even second interval)/K;

calculating a starting (i1) and ending (i2) symbol positions of a actual Turbo transmitted packet are from i1=1+mod(kL,M), i2=i1+L−

1, the Turbo coded packet being viewed as a periodic signal with period M, where N is the user payload packet size in number of symbols, M is the coded packet size, which is the packed size (in number of symbols) after Turbo coding, and L is the actual transmitted packet size in number of symbols resulting in an effective coding rate would be N/L;

a wireless terminal deriving packet size information, and using the count value, determining which portion of the turbo coded packet the received packet belongs to.

43. A method according to claim 3 further comprising assigning voice Walsh codes by:

assigning each voice user a voice channel number V (V=0, 1, 2 . . . ) which is used to calculate the one or two 16-ary Walsh codes on which the voice user will receive voice information;

using a supplemental paging channel (SPCH) to broadcast the number of 16-ary Walsh codes available for data only shared channel slots (Nd) and the number of 16-ary Walsh codes available for Voice in Hybrid shared channel slots (Nv);

calculating the two Walsh codes for a particular user, W×

116 and W×

216 according to X1=15−

mod(V,Nv) and X2=15−

mod(V+1, NV).

44. A method according to claim 1 further comprising:

transmitting a given user'"'"'s voice content using a Walsh cover previously made known to the given user.

45. A method according to claim 30 further comprising using negative acknowledgment (NAK) and acknowledgement (ACK) signals for outer loop power control in voice and data transmissions.

46. A method according to claim 45 wherein the outer loop power control comprises:

calculating a forward link frame error rate by counting a number of NAK and no ACK/NAK frames; and

determining outer loop power control based upon said forward link frame error rate.

47. A method according to claim 1 further comprising explicitly indicating a data rate for the shared channel by:

providing an explicit data rate sub-channel indicating packet size, packet length and a slot type flag indicating whether the slot is for one data-only user or for a data user and one or more voice users.

48. A method according to claim 1 wherein:

each slot comprises a plurality of pre-defined data transmission periods during which data and/or voice can be transmitted only, has at least one pre-defined period during which pilot data is transmitted only, and at least one pre-defined period during which MAC channel is transmitted only.

49. A method according to claim 48 adapted to transmit multi-user slots, each multi-user slot having a preamble containing said user identification channel, and to one slot and multi-slot single user high-rate transmissions, each first slot of a single user high-rate transmission having a preamble containing said user identification channel.

50. A method according to claim 49 wherein the forward pilot channel is transmitted by each sector in each half slot on the forward channel as unmodulated BPSK.

51. A method according to claim 49 wherein the pilot channel is transmitted as 96 chip bursts every half slot at full sector power.

52. A method according to claim 49 wherein each slot comprises a first 304 chip data period, a first 32 chip MAC channel slot, a 96 chip pilot burst, a second 32 chip MAC channel slot, second and third 304 chip data periods, a third 32 chip MAC channel slot, a second 96 chip pilot burst, a fourth 32 chip MAC channel slot, and a fourth 304 chip data period.

53. A method according to claim 52 wherein the MAC channel is used to transmit forward power control commands and reverse activity commands.

54. A method according to claim 52 wherein:

each voice user is assigned at least one group ID;

each data user is assigned a group ID;

a single group ID is transmitted on the preamble, so as to inform any user(s) having been assigned that group ID that the slot has content for the user.

55. A method according to claim 54 wherein:

each voice user has three Group IDs, one GID1 for use when its voice is transmitted using one 16-ary Walsh cover, one GID2 for use when its voice is transmitted using two 16-ary Walsh covers, and one GID4 for use when its voice is transmitted using four 16-ary Walsh covers;

wherein each user has Walsh covers assigned to it for each of the its three Group IDs such that when a given group ID is transmitted, then all voice users having been assigned the given group ID will know the slot contains their content, will know how many Walsh codes recover and which Walsh codes to recover.

56. A method according to claim 1 adapted to transmit data using parameters from any row of the table in FIG. 5A.

57. A method according to claim 1 adapted to transmit voice using parameters from any row of the table in FIG. 5B.

58. A method according to claim 1 adapted to transmit voice using parameters from any row of the table in FIG. 5C.

59. A method according to claim 1 adapted to transmit voice using parameters from any row of the table in FIG. 5D.

60. A method according to claim 2 adapted to transmit voice using parameters from any row of the table in FIG. 12.

61. A method according to claim 2 adapted to transmit data using parameters from any row of the table in FIG. 13.

62. A method according to claim 2 adapted to transmit data using parameters from any row of the table in FIG. 14.

39. A method according to 32 wherein sector selection precludes the changing from a sector value directly to another sector value, only allowing a change from a sector value to a null value then to another sector value.

63. A method of informing a particular user whether a current slot of a shared data channel contains data for the user, the method comprising:

providing a user identification channel;

transmitting a user identifier comprising a Walsh code and a sub-identifier.

64. A method according to claim 63 wherein the sub-identifier is an N bit identifier, and the Walsh code is one of P M-ary Walsh codes.

65. A method according to claim 64 wherein the user identification channel is transmitted in K chip slots, and has I and Q channels, thereby providing a 2*K/(M) bit capacity, and an ability to transmit 2*K*M/N user identifiers per slot.

66. A method according to claim 65 wherein M=512, K=1536, N=3 and P=16 thereby providing an ability to transmit 32 user identifiers per slot, and an ability to uniquely identify 128 different users.

67. A method according to claim 65 wherein M=512, K=1536, N=3 and P=8 thereby providing an ability to transmit 16 user identifiers per slot, and an ability to uniquely identify 64 different users.

68. A method according to claim 63 wherein a voice only user is assigned a single user identifier, and a user with voice and data is assigned one user identifier for data and one user identifier for voice.

69. A method according to claim 63 wherein for a given slot during which high-rate data is to be transmitted, data is transmitted for a high-rate data user likely to have good channel conditions during the slot.

70. A method according to claim 63 further comprising performing adaptive modulation and coding for high rate data users based on channel estimates fed back every slot.

77. A wireless terminal according to claim 70 further adapted to perform fast ARQ for voice.

71. A method of assigning voice Walsh codes comprising:

assigning each voice user a voice channel number V (V=0, 1, 2 . . . ) which is used to calculate one or two 16-ary Walsh codes on which it will receive voice information;

using a Supplemental Paging Channel (SPCH) to broadcast the number of 16-ary Walsh codes available for Data only shared channel slots (Nd) and the number of 16-ary Walsh codes available for Voice in Hybrid shared channel slots (Nv);

calculating the two Walsh codes for a particular user, W×

116 and W×

216 according to X1=15−

mod(V,Nv) and X2=15−

mod(V+1,Nv).

72. A wireless terminal adapted to function in a CDMA communications system, the terminal comprising:

a receiver adapted to receive frames having a slot structure in which there is a user identification channel and a shared channel, the shared channel having been transmitted using a plurality of Walsh codes, and containing content for either a plurality of voice users, a plurality of voice users and one high-rate data user, or only one high-rate data user;

the wireless terminal being adapted to decode the user identification channel to determine if a current slot of the shared channel contains voice and/or high-rate data content for the wireless terminal (voice content being voice or low-rate data).

73. A wireless terminal according to claim 72 wherein in the event the wireless terminal determines the current slot contains voice content for the wireless terminal, the receiver is adapted to blindly distinguishing between a plurality of different coding and modulation types which may have been used to transmit the voice content based on getting a correct CRC.

74. A wireless terminal according to claim 72 adapted to decode the user identifier channel using an assigned user identifier Walsh and sub-identifier.

75. A wireless terminal according to claim 72 adapted to be assigned at least one group ID as a voice user and adapted to be assigned a group ID as a data user;

wherein a single group ID is transmitted on a preamble of each slot, so as to inform the wireless terminal whether that the slot has content for the user.

76. A wireless terminal according to claim 75 wherein each voice user has three Group IDs, one GID1 for use when its voice is transmitted using one 16-ary Walsh cover, one GID2 for use when its voice is transmitted using two 16-ary Walsh covers, and one GID4 for use when its voice is transmitted using four 16-ary Walsh covers;

wherein each user has Walsh covers assigned to it for each of the its three Group IDs such that when a given group ID is transmitted, then all voice users having been assigned the given group ID will know the slot contains their content, will know how many Walsh codes recover and which Walsh codes to recover.

78. A wireless terminal according to claim 72 adapted to perform fast ARQ for voice by:

determining a correlation result based on the user identifier channel;

if the correlation result is greater than a first threshold and less than a second threshold, the wireless terminal decoding further channels, and if these channels pass an integrity check, sending an ACK to the base station, and otherwise, the wireless terminal discarding the current packet;

if the correlation result is greater than the second threshold, the wireless terminal decoding further channels, and if these channels pass an integrity check, sending a ACK signal to the base station, and if these channels do not pass the integrity check sending an NAK to the base station.

79. A wireless terminal according to claim 78 further adapted to save current packet raw data samples for soft combining or incremental redundancy with the future received data packet.

80. A wireless terminal according to claim 72 further adapted to look for a single user identifier if the terminal is expecting voice only, and if the terminal is expecting voice and data, to look for two user identifiers, one for voice and one for data.

81. A wireless terminal according to claim 80 further comprising:

in the event a current slot contains data for the wireless terminal as determined by the user identification channel, decoding another forward link channel to determine parameters used in transmitting the data packet, and then using a data rate determined from the another forward link channel to demodulate the data on the shared channel.

82. A wireless terminal according to claim 72 further adapted to perform voice ARQ.

83. A wireless terminal according to claim 82 adapted to perform voice ARQ using a 1×

RTT-like pilot channel.

84. A wireless terminal according to claim 83 wherein the 1×

RTT-like pilot channel is further used to transmit a RRI (reverse rate indicator).

85. A wireless terminal according to claim 84 adapted to perform voice ARQ by transmitting VARQ bits subject to:

when functioning with a voice service only, the VARQ valid bit positions are in slots 3, 4, 7, 8, 9, 11, 12, 13 and 15 of a current frame and slots 0 and 1 of a next frame, with slots 2, 6, 10 and 14 being reserved for RRI (reverse rate indicator);

when functioning in with both data and voice services, the position for the VARQ is fixed within a frame at slots 9 and 10, with remaining slots used for reverse rate indicator.

86. A wireless terminal according to claim 82 adapted to:

when functioning as a wireless terminal of a mixed data and voice user, map each RRI (reverse rate indicator) symbol (3 bits) to a simplex code with length of 7 repeated twice and mapped to slots 0-8 and 11-15, with voice ARQ being one bit mapped into slot 9 and 10, the RRI being used to indicate whether the Reverse Dedicated Control Channel or Reverse Supplemental Channel or neither is active for the current frame;

when functioning as a wireless terminal of a voice only users, map the RRI bit to slots 2, 6, 10 and 12, with the voice ARQ being one bit mapped into any two consecutive slots that are not reserved for RRI.

87. A wireless terminal according to claim 82 further adapted to transmit a Channel Estimate and Sector Selector (R-CHESS) channel having a slot for each forward slot, with some slots containing channel estimates and other slots containing sector select values.

88. A wireless terminal according to claim 87 wherein the CHESS channel is adapted to allow sector selection for data users which precludes the changing from a sector value directly to another sector value, only allowing a change from a sector value to a null value and then to another sector value.

89. A wireless terminal according to claim 88 wherein if the sector select value changes from a first sector value to a null value, the wireless terminal is adapted to continue to report channel estimates for the first sector value for a number of subsequent slots;

when the sector select value changes to a different sector value, the wireless terminal starts to report channel estimates for this new sector.

90. A wireless terminal according to claim 87 wherein each channel estimate comprises a three bit value representative of an absolute channel estimate.

91. A wireless terminal according to claim 87 wherein the channel estimates comprise three bit values alternating between being representative of an absolute channel estimate and a change in channel estimate.

92. A wireless terminal according to claim 87 wherein:

sector select values are sent during the first and ninth of sixteen available CHESS channel slots, and channel estimates are sent during the remaining of the slots.

93. A wireless terminal according to claim 72 adapted to process packets sent on a shared channel providing systematic predetermined incremental redundancy symbol selection for voice and data in which an even second timing referenced to UTC (Universal Coordinated Time) has been used to select a portion of turbo coded data symbols to be sent in a given slot, a count value k is used which starts on each even second which counts from k=0 to Kmax incrementing every (even second interval)/K;

starting (i1) and ending (i2) symbol positions are calculated of a actual Turbo transmitted packet are from i1=1+mod(kL,M), i2=i1+L−

1, the Turbo coded packet being viewed as a periodic signal with period M, where N is the user payload packet size in number of symbols, M is the coded packet size, which is the packed size (in number of symbols) after Turbo coding, and L is the actual transmitted packet size in number of symbols resulting in an effective coding rate would be N/L, the wireless terminal being adapted to process the packets by;

deriving packet size information, and using the count value, determining which portion of the turbo coded packet the received packet belongs to.

94. A wireless terminal according to claim 93 further adapted to decode the packet and performing a quality check on decoded packet;

if the decoded result does not pass the quality check, check if the previous received packet was decoded correct or not;

if the previous received packet is wrong, the current received packet will be used for soft combining and/or incremental redundancy with the previous received packet;

if the previous received packet is correct or the joint decoded result is wrong, a NAK signal is sent to the base station, and the current received packet will be stored and may be used for soft combining and/or incremental redundancy with the future received packet.

95. A wireless terminal according to claim 72 adapted to transmit supplementary channel(s) according to parameters in any row of the tables in FIG. 22 and FIG. 23.

96. A method for time division multiplexing of reverse supplemental channel and reverse control channel, said method comprising:

multiplexing said a supplemental channel and a control channel;

indicating, via a reverse rate indicator (RRI), whether a supplemental channel or a control channel or neither is active;

wherein said method enables sharing of channels by physical resources in wireless terminal modems and base station modems.