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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 multipl

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.

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We claim: 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 ch

We claim: 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 in parallel with the shared channel using a different code space, the user identification channel being 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 user. 3. A method according to claim 1 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. 4. A method according to claim 3 wherein the predetermined maximum number of Walsh covers is 14 16-ary Walsh covers. 5. A method according to claim 1 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. 6. A method according to claim 5 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. 7. A method according to claim 6 further comprising transmitting control information in respect of the shared data channel. 8. A method according to claim 7 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. 9. A method according to claim 8 wherein the control information comprises a data packet size and single/hybrid slot indicator for low 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. 10. A method according to claim 1 wherein at least some of the slots contain voice transmitted at full rate. 11. A method according to claim 10 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. 12. A method according to claim 1 wherein at least some of the slots contain voice content transmitted using half, quarter or eighth rate. 13. A method according to claim 10 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. 14. A method according to claim 1 wherein frames have a 20 ms duration, with each frame consisting of sixteen 1.25 ms slots, and each slot containing 1536 chips. 15. A method according to claim 1 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. 16. A method according to claim 15 wherein the sub-identifier is an N bit identifier, and the Walsh code is one of P M-ary Walsh codes. 17. A method according to claim 16 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. 18. A method according to claim 15 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. 19. A method according to claim 15 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. 20. A method according to claim 14 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. 21. 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. 22. A method according to claim 21 further comprising performing adaptive modulation and coding for the shared data channel based on channel estimates fed back every slot. 23. A method according to claim 1 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 8 PSK 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. 24. 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. 25. A method according to claim 24 wherein the VARQ signals are received on a 1횞RTT-like reverse pilot channel in place of predetermined former power control bit locations. 26. A method according to claim 25 wherein reverse rate indicator (RRI) signals are also received on the 1횞RTTT-like reverse pilot channel in place of predetermined former power control bit locations. 27. A method according to claim 26 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. 28. A method according to claim 27 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. 29. 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. 30. 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. 31. A method according to claim 1 further receiving channel estimates from each user. 32. A method according to claim 31 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. 33. A method according to claim 32 further comprising receiving sector select values from each user. 34. A method according to claim 33 wherein the channel estimates and sector select values are received on a Channel Estimate and Sector Selector (R-CHESS) channel from each user. 35. A method according to claim 34 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. 36. A method according to claim 35 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. 37. A method according to claim 35 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. 38. A method according to claim 35, further comprising precluding changing from a sector value directly to another sector value, and only allowing a change from a sector value to a null value then to another sector value. 39. A method according to claim 34 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. 40. A method according to claim 37 further comprising: requiring two sector select values corresponding to another valid sector to be received before the current active sector stops sending voice content. 41. 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 packet 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. 42. A method according to claim 1 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, W횞116 and W횞216 according to X1=15-mod(V,Nv) and X2=15-mod(V+1, Nv). 43. 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. 44. A method according to claim 29 further comprising using negative acknowledgment (NAK) and acknowledgement (ACK) signals for outer loop power control in voice and data transmissions. 45. A method according to claim 29 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. 46. 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. 47. 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. 48. A method according to claim 47 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. 49. A method according to claim 48 wherein a forward pilot channel is transmitted by each sector in each half slot on the forward channel as unmodulated BPSK. 50. A method according to claim 48 wherein a pilot channel is transmitted as 96 chip bursts every half slot at full sector power. 51. A method according to claim 48 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. 52. A method according to claim 51 wherein the MAC channel is used to transmit forward power control commands and reverse activity commands. 53. A method according to claim 51 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. 54. A method according to claim 53 wherein: each voice user has three Group IDs, one GID1 for use when its voice is transmitted using one 16-ary Walsh cover, one GID 2 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. 55. 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 and content for a voice user, transmitting a user identification channel in parallel with the shared channel using a different code space, the user identification channel being adapted to allow users to determine which slots contain their content. 56. An apparatus for transmitting over a forward link in a CDMA (Code Division Multiple Access) communications system, the apparatus comprising: transmitting means for transmitting forward link frames, each frame comprising a plurality of slots; said transmitting means being adapted to transmit, for each slot, 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 and content for a voice user, and wherein said transmitting means is arranged for transmitting a user identification channel transmitted in parallel with the shared channel using a different code space, the user identification channel being adapted to allow users to determine which slots contain their content. 57. A CDMA (Code Division Multiple Access) communications system, comprising an apparatus for transmitting over a forward link and a plurality of wireless terminals, wherein said apparatus comprises transmitting means for transmitting forward link frames, each frame comprising a plurality of slots, said transmitting means being adapted to transmit, for each slot, 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 and content for a voice user, and wherein said transmitting means is arranged for transmitting a user identification channel transmitted in parallel with the shared channel using a different code space, the user identification channel being adapted to allow users to determine which slots contain their content, wherein the wireless terminals comprise respective receivers adapted to receive the forward link frames, at least one of 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 said at least one of the wireless terminal.