EN_MultibandPBGT_HO

Aso,

This parameter is very special and is a key parameter for dual band network tuning, especially regarding collocated cells (1800 with 900)

if you disable it, you must then enable the capture HO cause 21 (preferred band HO)

your tuning will look like this:

In cells 1800:
EN MultiBand HO = Disable, to prevent HO back to 900 cells.
L_RXLEV_DL_H = -85dBm (threshold to exit the 1800 cell properly, since there is no more PBGT HO to 900 cells… this is a very special setting to allow a clean and smooth exit from 1800 to 900)

In cells 900:
EN Preferred band HO = Enable, to force HO towards 1800.
L_RXLEV_CPT_HO(900, 1800) = -80dBm (threshold to enter the 1800 cell)

in all cells:
HO MARGIN = 5dB

to summarize:
MS enters a 1800 cells at -80dBm
MS exits from 1800 cells at -85dBm
If you are not happy with the value, that’s ok, but keep in mind you must change both thresholds symmetrically.

the HO cause 5 (DL LEVEL HO) detected in a cell 1800 shall be now considered as a “better cell” HO, like the Power Budget HO 🙂

i gave you the recommended value in my previous post

by setting the high_traffic_load in the 1800 cells, you can increase or decrease the amount of HO preffered band form GSM900 to DCS1800 cells.

don’t forget to set, in the 900 cell, to set MULTIBAND TRAFFIC CONDITION = ANY LOAD.

if you increase high_traffic_load (1800) to 90%, then the number of HO will increase, pushing more traffic to 1800 until their load reach 90%