User Manual
Airbridge cBTS3612 CDMA Base Station
System Description
4 System Function
4-15
Eb/Nt value to issue power control bit, thus the purpose of indirectly controlling the
MS is achieved.
4.5.2 Handoff
I. Types
The handoff can be divided into the following three types according to the different
processing flow:
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Hard handoff
The MS will firstly interrupt the connection with the previous BTS, then set up the
connection with the new BTS.
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Soft handoff
When the MS establishes the communication with a new BTS, it will not release the
connection with the previous BTS.
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Softer handoff
It is the soft handoff occurred among different sectors in the same BTS.
II. Purpose
According to the purpose, the handoff can be divided into three types: rescue
handoff, better cell handoff and traffic handoff.
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Rescue handoff
When the MS is leaving the cell coverage area and the conversation quality is
unbearably poor, the handoff occurs in order to avoid the interruption of the call.
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Better cell handoff
If the rescue handoff condition is not triggered, this handoff may occur if
conversation quality or network performance can be improved. The handoff is called
better cell handoff because there is better cell for communication.
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Traffic handoff
This kind of handoff occurs when one cell is congested due to its heavy load and the
adjacent cell is relatively idle. This mainly results from traffic peak within short time
in a limited area due to some special events (such as sports, exhibition, etc).
4.5.3 Flexible Configuration
BTS supports the combination of three cabinets, so the maximum capacity can
reach 36 sector-carriers. BTS supports 1~12 carriers for each sector, omni or
directional coverage mode, and the configuration of 1~6 sectors. BTS can also