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Wireless Communication
CDMA EVDO Systems
Dr. Mustafa Shakir
Contents
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CDMA 1X Packet Data Service Functional
Entities
1X Packet Data Service Status
CDMA Evolution
EV-DO Network Architecture
EV-DO Channel structure
PDSN
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As a access gateway , PDSN (packet data service node)
provides the cdma2000 mobile station with services for
Internet access or Intranet access. PDSN acts as an
interface between Radio Network and Packet Data
Network.
Provides the mobile station with Simple IP access service
or Mobile IP access service. In Simple IP,PDSN acts as a
Network access server, while in Mobile IP,PDSN acts as
Foreign Agent (FA) for Mobile Station.
At the cdma2000 1x stage, the maximum access rate
available for each subscriber is 153.6kbps, and at the
cdma2000 1x EV-DO (Evolution Data Only) stage, the
maximum access rate available for each subscriber will be
as high as 2Mbps.
PDSN acts as a client of AAA server.
AAA

AAA authenticates the script file information of the
subscribers, authorizes data services, and Collects
accounting information from PDSN, completes
accounting.
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Authentication
 simple IP and mobile IP.
Authorization
 subscriber configuration information.
Accounting
 collecting billing data(both radio specific and IP network
specific) for each packet data call.
Home Agent
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HA(Home Agent) is responsible to maintain
the current registration of the MS and
redirections packets to the PDSN(FA).
Performs authentication and authorization
uses AAA server.
Assigns MS
home IP addresses after
authentication by mobile IP protocol.
Only uses in Mobile IP.
CDMA2000 1x Packet Domain
Access Method
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Simple IP Access
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Similar to the network access through dialing-up
modem on the fixed telephone . Assigning
dynamic IP addresses and accomplishing the data
communication with MS as the calling party .
Simple protocol, easily accomplish, but data
communication will be interrupted when MS
handoff between different PPP link.
Access Method (Cont.)
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Mobile IP Access
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Providing a route mechanism in the internet.
Assigning MS fixed addresses to connect to any
sub-network.
Accomplishing the data communication with MS
as the calling party or the called party, and holding
data communication when MS handoff between
different PPP link.
PDSN Mobile IP Access
Signaling
BTS
User Data
PDSN/FA
BSC/PCF
FW
MS
BTS
IP Network
FAAA
HA
FW
APP Servers
HAAA
Contents
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CDMA 1X Packet Data Service Functional
Entities
1X Packet Data Service Status
CDMA Evolution
EV-DO Network Architecture
EV-DO Channel structure
Service Status
Service Status
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Active/Connected: There are traffic channels between
Mobile Station (MS) and BS, and data can be
exchanged between them. In this state, the A10 and
PPP connections are kept.
Dormant: There are no traffic channels between MS
and BS. A10 and PPP connections remain.
Null/Inactive: There are neither traffic channels nor
A10 connections between MS and BS. Besides, there
is no PPP connection between MS and PDSN.
How to know? When Active, Dormant & Inactive
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1. About “DRS”
When a mobile terminal sends an origination
request with a packet data service option
specified, it will include the Data Ready to
Send (DRS) bit.
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When DRS bit set to 1 to indicate that it has data
to send.
When DRS bit set to 0 to indicate that it has not
data to send, just to update the network
How to know? When Active, Dormant by &
Inactive
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2. About “packet data inactivity timer”
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In BSC or MS, they both have a packet data
inactivity timer to identify whether there are data
frame sent/received or not.
The timer should be reset whenever non-idle Radio
Link Protocol data frames are sent or received.
If the packet data inactivity timer expires, the BSC
or MS should release the traffic channel.
Comparison of Wireless Systems
(CDMA Evolution)
1 Gbps
100 Mbps
Wi-MAX
10 Mbps
WLAN
CDMA2000 1xEVDO
1 Mbps
UMTS
Bluetooth
100 kbps
GSM / GPRS
Inside
Office
Inside
Building
Low Mobility
Outside
High Mobility
Outside
Contents


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CDMA 1X Packet Data Service Functional
Entities
1X Packet Data Service Status
CDMA Evolution
EV-DO Network Architecture
EV-DO Channel structure
1X EVDO Network Structure
Source
AN
PCF
PDSN
IP
Network
AT
A12
Target
AN
AAA
AN AAA
IP Network
AT
AN
AT access terminal
AN Access Network
A12 authentication used by the AN to authenticate 1x EV-DO Access terminal
Comparison of EVDO and 1x Networks
HLR
AAA
MSC
MS/AN
BTSB
BSCB
ANAAA
PCF
PDSN
Network Implementation