To reduce or increase the coverage of a cell, you may (primarily) tune the CPICH power :
Amos: get utranCell primaryCpichPower
By default, use 330 (ie. 33dBm)
Dependencies: primaryCpichPower less than maximumTransmissionPower
Decreasing the cpich will reduce the cell coverage, but also decrease the Ec/No of the users inside the cell. They will “hear” more interferences.
A good way to check the coverage distance of a cell is to extract the counter “pmPropagationDelay”, at RBS level (class prach)
Amos : pmx prach pmPropagationDelay -m 3 -a
Within one sector, only analyse cells with highest amount of samples (ie. where the UE are camping).