1. Dr. Shahzada Alamgir Khan
Fundamentals of EVDO
Dr. Shahzada Alamgir Khan

2. Contents Reverse Channel Enhanced
Reverse rate and RA sub-channelMulti Slot Packet Transmission
EVDO original intention and demand updating
Reverse Rate and RA Sub Channel

3. Reverse channel enhanced
AN uses reverse pilot channel to do coherent demodulation
Fixed frame length（16slots）, low rate Turbo coding（1/2 and 1/4）；
Reverse rate from 9.6kbps to 153.6kbps, and using RRI channel to indicate reverse rate
Reverse data rate is limited by AN, RAB 3

4. Reverse rate and RA sub-channel
RA sub-channel is used to indicate reverse link busy or not by AN
When the reverse link is busy, RAB set ‘1’; otherwise, RAB set ‘0’
AT adjusts reverse data rate by monitoring RA channel dynamically
When the reverse link is not busy, AT will increase data rate in a certain probability; When the reverse link is busy, AT will decrease data rate in another certain probability

5. EVDO original intention and demand updating
EVDO main intention：only for high rate packet data service
As subscribers demand change：
Diversified services
Uplink service higher rate
Concurrent packet and voice
More high-efficiency resource utilization

6. Goals EVDO A’s goals： Increase reverse link throughput
Increase forward link utilization
Support to QOS enhance
Improve 1x/DO dual mode operation

7. EVDO Rev.A Properties Lower layer enhanced Upper layer enhanced
Physical layer
Better support to QoS sensitive service
Higher spectrum efficiency
Higher peak rate
MAC layer
Rapid connection of control channel and access channel
Upper layer enhanced
Multi-flow packet application

8. Contt.
EVDO A new key technologies are so many, the important are as follow:
Reverse link ARQ *
Reverse resource control *
Seamless virtual soft handoff *
Rapid connection *
Multi-users packet
Crossed paging