Part 2: Principle and Implementation of EVDO Systems

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Part 2 Principle and Implementation
of EVDO Systems

• WLL SHORT TRAINING

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Part 2 Principle and Implementation of CDMA2000
EVDO Systems
UNIT 1
EVDO Network Structure
EVDO CHANNEL STRUCTURE KEY TECHNIQUES
UNIT 2
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EVDO Theory Unit 1
EVDO NETWORK STRUCTURE
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1X EVDO Network Structure
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Comparison of EVDO and 1x Networks

HLR
AAA
MSC
PDSN
MS/AN
BTSB
BSCB
PCF

ANAAA
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Network Implementation
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Changed Parts in Upgrading

• BTS side
• - If new EVDO carrier is added
• Add EVDO base band processing part
• Add related Radio transmission part, keep antenna
  and feeder.
• - If upgrading 1x carrier to EVDO carrier
• Add EVDO base band processing part
• Keep antenna and feeder no change

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Changed Parts in Upgrading (Cont.)

• BSC side add EVDO processing part, upgrade
  related software
• - EVDO Signaling
• -Increased EVDO data capacity

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Part 2 Principle and Implementation of CDMA2000
EVDO Systems
UNIT 1
EVDO Network Structure
EVDO CHANNEL STRUCTURE KEY TECHNIQUES
UNIT 2
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EVDO Channel Structure Key Techniques

• Forward Link Channel Structure
• Reverse Link Channel Structure
• Key Techniques

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Forward Channel Structure
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Forward Data Time Slot
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Forward Pilot Channel

• The Pilot channel is sent as 96 chip bursts, each
  of which is located at the center of each half
  slot.
• The Pilot channel is transmitted at the full
  sector power.

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Forward MAC Channel

• The Reverse Power Control Channel (RPC channel)
  and the DRCLock Channel are time-division
  multiplexed.
• RPC channel is used for reverse power control.
• DRCLock is used to indicate if the reverse Date
  Rate Control (DRC) channel message is received or
  not.
• Reverse Activity (RA) channel is CDMed with RPC
  channel DRCLock channel
• Reverse Activity Bit (RAB) is transmitted in RA
  channel, which is broadcasted by AN to inform ATs
  the current reverse traffic channel status.

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MAC Index
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Forward Control Channel
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Forward Control Channel

• Data rate is 38.4 or 76.8kbps.
• The Control Channel Cycle is of 256 slots.
• Broadcast Overhead messages and Page messages are
  always delivered by using Synchronous Capsule
  (AC).
• Asynchronous Capsule (AC) used to deliver ACK
  messages and RLP Control messages, may be sent
  at any time during which the AN is not sending a
  synchronous capsule.

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Forward Traffic Channel

• Supported data rates 38.4, 76.8, 153.6, 307.2,
  614.6, 921.6, 1228.8, 1843.2, and 2457.6 Kbps.
• QPSK, 8PSK and 16-QAM are used.
• Channel encoders with different code rates are
  used.
• Physical layer packets are of four different
  lengths 1024 bits, 2048 bits, 2072 bits and 4096
  bits.
• A preamble is attached as the header of each
  physical layer packet.
• The transmitted packet preamble physical
  layer packet

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Forward Traffic Channel Parameters
Data rate (kbps) Slots per Packet Packet Size (bits) Code Rate Repetition Modulation Preamble (chips) Effective code Rate
38.4 16 1024 1/5 9.6 QPSK 1024 1/48
76.8 8 1024 1/5 4.8 QPSK 512 1/24
153.6 4 1024 1/5 2.4 QPSK 256 1/12
307.2 2 1024 1/5 1.2 QPSK 128 1/6
307.2 4 2048 1/3 49/48 QPSK 128 16/49
614.4 1 1024 1/3 1 QPSK 64 1/3
614.4 2 2048 1/3 49/48 QPSK 64 16/49
921.6 2 3072 1/3 49/48 8PSK 64 16/49
1228.8 1 2048 1/3 0.5 QPSK 64 2/3
1228.8 2 4096 1/3 49/48 16QAM 64 16/49
1843.2 1 3072 1/3 0.5 8PSK 64 2/3
2457.6 1 4096 1/3 0.5 16QAM 64 2/3