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WP-CDMA Distinguishing Features. 1. Uplink Common Packet Channel (All Rates). Common Packet Channel will transport all data rates up to. ·. and including 2.048 Mbps. ·. Constant Power Level Preamble with 16 possible sequences. Closed Loop Power Control, Preamble Ramp-up mechanism. ·.
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WP-CDMA Distinguishing Features 1. Uplink Common Packet Channel (All Rates) Common Packet Channel will transport all data rates up to · and including 2.048 Mbps. · Constant Power Level Preamble with 16 possible sequences Closed Loop Power Control, Preamble Ramp-up mechanism · Fast L1 ACK mechanism (within 250 micro-seconds) · • Collision Detection with Low Feedback Delay (2 ms) • Downlink Common Power Control Structure 2. Common Control Channel in the Downlink 3. Intra-frequency Hard Handover 4. Quick Handover 5. Structure of the WP-CDMA CCPCH (Common Control Physical Channel) • TM Common Pilot for coherent demodulation • Adjustable Power SCH1 And SCH2 for faster initial cell search 6. Multi-code Option for Higher Rates • The relationship between the VSF and number of multi-codes is the subject of • further study 7. Higher APC Rates 8. Removal of Link Maintenance Channel
WP-CDMA Distinguishing Features DL Common Control Channel • There are N power control channels associated with each user. These power • control channels are time multiplexed. • The pilot symbols required for coherent detection are time multiplexed with the • other control information in the Common Control Channel in the DL direction. • Messages such as L1 ACK (Busy). Free. CD. ARQ ACK/NAK will be sent through • the Common control Channel as well. Some of the messages such as L1 ACK, • TPC and CD bits are not interleaved since fast response time is required. • L1 ACK requires a predetermined time allocation in the .625 ms slot. This is • required every other slot at the end of the DSMA/CDMA-CD mini-slot which • corresponds to the .25 ms guard time. • Other less delay sensitive messages and commands go through the signaling • channel which is time multiplexed with other information in the Common Control • Channel.
DL Common Control Slot Structure Pilots NPilots Slot 0 CD CD PC2 PC1 CD CD PCn SIGNALING … TFI SF=64 SF=TBD SF=TBD 625 µs L1 ACK NACK Pilots NPilots PC2 PC1 SIG SIG SIG PCn … Slot 1 TFI 375 µs