User Manual
Airbridge cBTS3612 CDMA Base Station
System Description
4 System Function
4-17
Channel type
Channel rate (bit/s)
RC1
9600, 4800, 2400, or 1200
RC2
14400, 7200, 3600, or 1800
RC3
9600, 4800, 2700, or 1500 (20ms frames)
R-FCH
RC4
14400, 7200, 3600, or 1800 (20ms frames)
RC1
9600
R-SCCH
RC2
14400
RC3
153600, 76800, 38400, 19200, or 9600 (20ms frame)
R-SCH
RC4
307200, 153600, 76800, 38400, 19200, or 9600 (20ms frame)
II. Physical channel configuration
On Um interface is defined series of physical channels, which are divided into
different types according to the channel features. Different RCs support different
channels.
1) Forward physical channel
The configuration of forward physical channel is shown in Figure 4-11.
F-TCH
Forward CDMA channel
F-CACH
F-CPCCH
F-PICH
F-CCCH
F-DCCH
F-FCH
F-PC
F-SCCH
F-SCH
F-PICH
F-TDPICH
F-APICH
F-ATDPICH
F-SYNCH
F-BCH
F-PCH
F-QPCH
Sub-channel
(RC1~2)
(RC3~5)
Figure 4-11
Forward physical channels
l
F-CACH (Forward Common Assignment Channel )
F-CACH is specially used for transmitting the assignment information in quick
response to the reversed channel, and provides the support for random access
packet transmission in the reversed link. F-CACH controls R-CCCH (Reverse
Common Control Channel) and F-CPCCH in Reservation Access Mode, and
provides the quick acknowledgement in power-controlled access mode. In addition,
it also provides congestion control function.
l
F-CPCCH (Forward Common Power Control Channel)
F-CPCCH is used in the system to support multiple R-CCCH and R-EACH (Reverse
Enhanced Access Channel) to perform power control.