User Manual
Airbridge cBTS3612 CDMA Base Station
System Description
4 System Function
4-5
MS
BTS
BSC
Paging Response
Abis-ACH Msg Transfer(PRM)
Abis-PCH Msg Transfer(Base Ack)
Base Ack Order
Abis-BTS Setup
Abis-Connect
Abis-Connect Ack
Abis-BTS Setup Ack
Abis-IS2000 FCH Fwd(Null data)
Null Traffic Data
Abis-IS2000 FCH Rvs(Idle data)
Abis-PCH Msg Transfer(ECAM)
ECAM
Traffic Channel Preamble
Abis-IS2000 FCH Rvs(Preamble)
Abis-IS2000 FCH Fwd(Base Ack)
Base Ack Order
Idle TCH Data
Abis-IS2000 FCH Rvs(Idle Data)
MS Ack Order
Abis-IS2000 FCH Rvs(Ms Ack)
Abis-IS2000 FCH Fwd(Service Connect)
Service Connect Msg
Service Connect Complete
Abis-IS2000 FCH Rvs(Ser Conn Comp)
CM Service Req
Assignment Complete
MSC
Assignment Req
Paging Request
Abis-PCH Msg Transfer(GPM)
GPM
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
PCH
ACH
PCH
TCH
PCH
TCH
TCH
TCH
TCH
TCH
TCH
Figure 4-5
MS-terminated call procedure
1) MSC sends "Paging Request" to BSC.
2) BSC constructs General Paging Message (GPM), embeds it into”Abis-PCH
Msg Transfer” message, then sends it to BTS. BTS sends the GPM on the
paging channel.
3) After MS receives paging message, it sends "Paging Response" message
(PRM) to BTS. BTS forwards it to BSC in “Abis-ACH Msg Transfer” message.
4) BSC sends “CM Service Request” message to MSC, to request service
assignment.
5) BSC sends “Base Ack” order to BTS via “Abis-PCH Msg Transfer” message.
BTS sends the “Base Ack” order on the paging channel.
6) MSC sends assignment request message to BSC, to request BSS to assign
radio resources.
7) BSC sends “Abis-BTS Setup” message to BTS, to request BTS to allocate
radio resource for the call.
8) BTS sends “Abis-Connect” message to BSC, to establish Abis service
connection.