ZTE Corporation ZXG-OB06 Manuale Utente
ZXG10 OB06 ZTE Integrated Outdoor GSM Base Station Technical Manual
50
Confidential and Proprietary Information of ZTE CORPORATION
2. Handover
The handover procedure is shown in Figure 35.
F
I G U R E
3 5
H
A N D O V E R
MS
LAPDm
FURRM
HPIMan
LAPD
BSC
OAMM
(PHY INFO)
Dm_DL_DATA_I
ND (HANDO
COM)
(HANDO DET )
DL_DATA_REQ (DATA
IND (HANDO COM))
DL_DATA_IND (DATA REQ
(RR HANDO CMD))
Dm_DL_DATA_
REQ ( HANDO
CMD)
(DATA REQ (RR
HANDO CMD))
HANDO CMD))
( HANDO
CMD)
Dm_DL_RANDO
M ACCESS_IND
(HANDO
ACCESS)
DL_DATA_REQ (HANDO DET )
Dm_DL_UNIT
DA TA_REQ
DA TA_REQ
(PHY INFO)
T3105
(HANDO
COM)
(DATA IND
(HANDO COM))
Repeat
Ny1 times
DL_DATA_REQ (CONN FAIL IND)
(CONN FAIL IND)
T3105, Ny1
(end)
CHP RET NORM
ACTIV
Dm_DL_EST_IND
(correct L2 frame)
DL_DATA_REQ (EST
IND)
(EST IND)
remark
The handover enables an MS in the dedicated mode to move into another
channel of another cell.
channel of another cell.
When the BSC receives the HANDO REQ message from the MSC, the BSC
enables the new channel activation procedure. The CHAN ACTIV message
enables the new channel activation procedure. The CHAN ACTIV message
sent to the TRX contains Handover Reference, which will be used to detect
the Handover Access message from MS.
the Handover Access message from MS.
When the channel for handover is activated, the FURRM uses the CHP RET
NORM ACTIV message to notify the CHP to resume the normal mode.
NORM ACTIV message to notify the CHP to resume the normal mode.
The FURRM should save the Handover Reference in the CHAN ACTIV
message, to compare it with the Handover Reference in the Handover
Access message that is sent by the LAPDm.
message, to compare it with the Handover Reference in the Handover
Access message that is sent by the LAPDm.
The (RR) HANDOVER COMMAND message is sent on the active DCCH. This
transparent message contains new channel characteristics, power
transparent message contains new channel characteristics, power
command, physical channel establish procedure indication, handover
reference, time lead (optional) and encryption mode setting (optional). It
reference, time lead (optional) and encryption mode setting (optional). It
also controls whether to connect MS first in synchronous activation mode.
About the physical channel establishment, in case of synchronous
handover, when MS is to be connected on the allocated channel, it will
send four (RR) HANDOVER ACCESS messages on the active DCCH in one
send four (RR) HANDOVER ACCESS messages on the active DCCH in one