When you work with 900/1800 network, you should make a decision :
which handover cause will you use to push traffic from 900 to 1800 cells ?
– cause 14 : umbrella to mini cells
– cause 21 : 900 cells to 1800 cells.
I recommend the cause 21 if you didn’t attend to the specific alcatel training about multiband management.
cell type = Single for all cells
**in GSM900 cells:
CELL_RESELECT_OFFSET = 0dB
RXLEV_ACCESS_MIN = -104dBm
EN_PREFERRED_BAND = enable
L_RXLEV_CPT_HO(900,1800) = -80dBm
MULTIBAND_TRAFFIC_CONDITION = Any_Load
**in DCS1800 cells:
CELL_RESELECT_OFFSET = 22dB
RXLEV_ACCESS_MIN = -90dBm
EN_MULTIBAND_PBGT_HO = disable
L_RXLEV_DL_H = -86dBm
That’s a good start to balance traffic, quite simple to deal with. Other parameters don’t have any effect on this method.
Beware that cause PBGT is forbidden from 1800 cells to 900 cells, and that the handover cause 5 (low level in DL) is the only way to exit a 1800 cell towards a 900 cell.
PBGT HO is available between two 1800 cells, of course.