1. 2003.03.17Lucent Shared FCH/DCCH Proposal1 TSG-C TITLE: Shared FCH/DCCH Proposal SOURCE: Doug Knisely dnk@lucent.com +1-630-979-7344 – Work ABSTRACT: This proposal provides an alternative shared channel design that is complementary to the BSCH offered by Qualcomm. RECOMMENDATION: Review and initiate Release D work on this proposal. Lucent Technologies grants a free, irrevocable license to 3GPP2 and its Organizational Partners to incorporate text or other copyrightable material contained in the contribution and any modifications thereof in the creation of 3GPP2 publications; to copyright and sell in Organizational Partner's name any Organizational Partner's standards publication even though it may include all or portions of this contribution; and at the Organizational Partner's sole discretion to permit others to reproduce in whole or in part such contribution or the resulting Organizational Partner's standards publication. Lucent Technologies is also willing to grant licenses under such contributor copyrights to third parties on reasonable, non-discriminatory terms and conditions for purpose of practicing an Organizational Partner’s standard which incorporates this contribution. This document has been prepared by Lucent Technologies to assist the development of specifications by 3GPP2. It is proposed to the Committee as a basis for discussion and is not to be construed as a binding proposal on Lucent Technologies. Lucent Technologies specifically reserves the right to amend or modify the material contained herein and to any intellectual property of Lucent Technologies other than provided in the copyright statement above. C20-20030317-002

2. 2003.03.17Lucent Shared FCH/DCCH Proposal2 Motivation 1.Packet Data Control Channel –Currently, a Fundicated Channel Must be Assigned to Each MS (Non-PDCH Case) –Most Data Traffic Carried on SCH; Signaling and Control Information on Fundicated Channel has Small Duty Cycle for a Given MS => Wasteful Use of Resources => Walsh Code Waste –Especially Prevalent Problem with Mixed PDCH and Pre-PDCH Traffic Due to Walsh Space Fragmentation 2.True Multicast/Broadcast Packet Data Service –Proposed BSCH Only Applicable for Common Channel Operation No Power Control or Other Feedback Not Applicable while on Traffic Channel for Other Services

3. 2003.03.17Lucent Shared FCH/DCCH Proposal3 Key Elements of the Proposal Shared F-DCCH: Two Modes –Broadcast Fundicated Channel – All MSs Assigned to Walsh Code Receive Common Traffic Stream –“Multi-Unicast” – Traffic is TDMed between a Set of MSs Sharing a Common Walsh Code Shared F-FCH –Broadcast Fundicated Channel – All MSs Assigned to Walsh Code Receive Common Traffic Stream Shared F-SCH –Broadcast Supplemental Traffic Channel – All MSs Assigned to Walsh Code Receive Common Traffic Stream

4. 2003.03.17Lucent Shared FCH/DCCH Proposal4 Multicast Stream Example Configuration

5. 2003.03.17Lucent Shared FCH/DCCH Proposal5 Broadcast/Multicast Forward Traffic Channel Key Features 1.Shared F-DCCH for Forward Signaling –Unicast on a Shared Walsh Code –TDM by LCM 2.Shared F-FCH or F-DCCH for Forward Data Traffic –Multicast on a Shared Walsh Code –Appropriate for Shared Voice and/or Data Streams 3.Shared F-SCH for Higher Rate Forward Data Traffic

6. 2003.03.17Lucent Shared FCH/DCCH Proposal6 Broadcast/Multicast Forward Traffic Channel Details 1.Sharing is on a Leg-by-Leg Basis –As far as the MS is concerned, each leg is being unicast to it. –BS may configure legs to be shared or non-shared according to whether: More than one MS needs a “copy” of the same stream of data, or More than one MS can share an F-DCCH Walsh code for control information. 2.Highly Dynamic Membership in Shared Streams; Data Traffic Channel May be Shared or Non-shared Independently on Each Leg 3.Forward Power Control Bits are Multiplexed on CPCCH to Control Multiple Reverse Links 4.Reverse Link Identical to 3G1X 5.Processing of Power Control Bits from MSs at BS is Not Specified by Standard; Could Use Various Techniques, e.g., “Or of Up Bits” 6.Note: Data == Any Voice, Data, or Combination in this Presentation

7. 2003.03.17Lucent Shared FCH/DCCH Proposal7 Example: Multicast F-FCH and Shared F-DCCH for TDM Control of Packet Data MS is Essentially Unaware of the Multicast Forward Link –Similar to “V2” BSP –Signaling Coming from a DCCH; DTX’ed when Nothing for User i –Forward Voice/Data Traffic over F- FCH –New CPCCH Power Control Mode MS Reports PSMMs as Usual; BS Adds/Drops Legs in Usual Manner –Same Forward Legs May be Shared, but MS is Oblivious BS Identifies Multiple Copies of Common Data Stream and (Re)assigns them to a Shared F-FCH BS Controls F-FCH Power, e.g., by OR of Up Bits BS Controls F-DCCH Traffic for MS 1 and F-CPCCH Slot for MS 1 via Individual PC Bits from MS Notes: –Set U of Users Sharing F-DCCH is Independent of Set G of Users Sharing F-FCH Data Stream and Set P of Users Sharing F-CPCCH

8. 2003.03.17Lucent Shared FCH/DCCH Proposal8 Additional Comments Examples in this Presentation Show Low Rate Shared F-FCH; the Same Principals Work and Should be Supported in the Standard for a Shared F-SCH for Higher Rate Streams –Additional Power Control Modes Needed, but Essentially Analogous to Existing SCH PCMs Additional Enhancements to Shared F-DCCH are Possible: –Slotted Operation to Reduce MS Processing and Battery Load Complimentary to and Compatible with Qualcomm Broadcast SCH Proposal –Traffic Channel Analog –Readily Integrated with a Common Multicast Architecture (i.e., BCMCS AHG Architecture) –Readily Integrated with FEC and Coding Features (e.g., RS FEC) Works Well with 5 ms SCAMs to Control F-SCHs with Reduced Walsh Code Requirements

9. 2003.03.17Lucent Shared FCH/DCCH Proposal9 Benefits Excellent Fit for High Priority Applications: –Low Rate Multi-cast Datastreams (e.g., Information Services, Status/Traffic/Weather, Location- Dependent Info Directed to Many MSs) –High or Low Rate Multi/Broadcast Datastreams that are Accessible from the Traffic Channel –Push to Talk Compatible with Existing 3G1X Forward Link –BS (Esp. BTS) Re-use; Software-only Feature Compatible with Existing 3G1X Reverse Link –Potential Re-use of Existing ASICs with only Software Changes Straightforward A Interface Extensions; Minimal Changes (if Any) Synergistic with F-PDCH: –Shared F-DCCH for Signaling/Control is Beneficial for QoS Constrained Environments and when F- DCCH Variance is a Poor Match for Signaling Traffic Extremely Efficient Conservation of Walsh Codes Suitable for Gradual Introduction: –V1 => V2 (Shared DCCH; Dedicated FCH) => V2 w/CPCCH => V2 w/Shared F-FCH Robust: –Fallback to Conventional V2 or Even V1 as Needed; Transparent to MS –Seamless Transition from “Multi-Unicast” to Share Traffic Channel as Users who are Sharing the Datastream are Added

10. 2003.03.17Lucent Shared FCH/DCCH Proposal10 Required Standards Extensions 1.New Power Control Modes: –F-CPCCH PC of Reverse Link; May Require Adjustment of Step Size Depending on Details of CPCCH Slotting 2.Multicast Long Code Mask for Shared Traffic Channel –Re-use/extension of PLCM Extensions in Release C? 3.Possible Slotting of Shared F-DCCH –Under Investigation; Appears to be Unnecessary Now 4.Multicast Stream Control for Multicast Control –Primarily Carried in Bearer IP Data between MS and PDSN –Stage 1 Exists –Stage 2 Proposal(s) on the Table in BCMCS Ad Hoc Group 5.Need to Permit Decoupled Frame Offsets for F-DCCH/F-FCH/F-SCH 6.Minimum Performance Specification Changes Changes to Air Interface are Limited to Upper Layer Signaling –No Impact on PHY, MAC, LAC

11. 2003.03.17Lucent Shared FCH/DCCH Proposal11 Conclusions/Recommendations WG 2 Should Evaluate and Approve Concept for Inclusion in Revision D