1/ what is your macro->micro Ho strategy ? ho PBGT, ho umbrella->micro, ho preferred band ?
you must act at 2 levels: the idle mode and the connected mode. The whole idea is to keep “static” MS in the micro, and keep “moving” MS in the macro.
* For idle : reduce the CRO of the micro cell, and increase the penalty time and temporary offset (pt = 60s, to = 40dB)
* For connected : avoid incoming HO from macro-> micro by increasing the averaging window of the macro-> micro HO
the BAD SACCH ho is very useful, but very powerful. You should strongly decrease the L RXLEV MCHO to a low level, for example : -93dBm, and keep the N BAD SACCH to a standard value (4). To keep good, qos, increase the L RXLEV DL H to -89dBm (or even higher).
2/ for road cell : set HO MARGIN (a,b) = HO MARGIN (b,a) = 0dB, and A PBGT HO = 6 SACCH.
if those two cells are also adjacent to “city” cell, then there is a risk of ping pong ho with them, becaus ethe A PBGT HO is so short. In this case, increase the HO Margin towards the city cell :
HO MARGIN (a, city) = 8dB (for example)
That will limit the ping pong effect.