handover due to uplink/downlink quality

hi,

my area has poor hosr and the dominant reason for HO is poor uplink/downlink quality.

i was thinking that maybe because those cells having poor hosr are facing areas where the boundary is a body of water (e.g. river, sea shore) then the poor quality must be caused by interference.

i’ve already checked for possible co/adj channel and there is none, activated power control, reduced max TA and power level for the BCCH, and downtilted the antenna.

is there anything else that i could do as solution? thanks. 🙂