Huawei Airbridge cBTS3612-1900 User Manual page 29

User Manual
Airbridge cBTS3612 CDMA Base Station
Layer 1 is the physical layer, i.e. the bottom layer. It includes various physical
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channels, providing a basic radio channel for the transmission of higher layer
information.
Layer 2 is the data link layer, including Medium Access Control (MAC) sublayer
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and Link Access Control (LAC) sublayer. The cdma2000 MAC sublayer
performs the mapping between logic channels and physical channels, and
providing Radio Link Protocol (RLP) function. The cdma2000 LAC sublayer
performs such functions as authentication, Automatic Repeat Request (ARQ),
addressing and packet organization.
Layer 3 is the top layer. It performs Radio Resource Management (RM),
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Mobility Management (MM) and Connection Management (CM) through the air
interface.
III. Physical layer
1) Operating band
Band
450MHz
800MHz
1900MHz
2) Physical layer function
Service bearer: the physical channel in the physical layer provides bearer for
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the logic channel of the higher layer.
Bit error check: the physical layer provides a transmission service with error
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protection, including error checking and error correction.
User identification: the physical layer provides an exclusive ID for every user by
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code division.
3) Radio configuration
The cdma2000 physical layer supports multiple Radio Configurations (RCs).
Different RCs support different traffic channel data rates. For detailed introduction,
please refer to Section 4.5.4 Radio Configuration and Channel Support.
IV. Data link layer
Data link layer at Um interface includes two sublayers: MAC and LAC. The purpose
of introducing MAC and LAC is to:
Support higher level services (signaling, voice, packet data and circuit data).
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Support data services of multiple rates.
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Support packet data service and circuit data service of higher quality (QoS ).
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Forward Band Reverse Band
460 - 470MHz 450 - 460MHz
869 - 894 MHz 824 - 849 MHz
1930 - 1990 MHz 1850 - 1910 MHz
1-12
System Description
1 System Overview
Duplex Channel Carrier Space
Space Wideth
10MHz 1.23 MHz
45MHz 1.23 MHz
80MHz 1.23 MHz
1.23 MHz
1.25 MHz
1.25 MHz