A hierarchical cell structure (HCS) cellular communications system
includes a macro cell encompassing a smaller micro cell that employ the
same frequency band. The macro cell includes a macro cell base station,
and the micro cell includes a micro cell base station. An uplink
communication cell boundary between the macro cell and the micro cell is
established, and a downlink communication cell boundary between the macro
cell and the micro cell is established. A radio network controller
determines whether a condition exists in the HCS system which indicates
that the uplink and downlink micro cell boundaries should be unbalanced.
If the condition is met or exists, the power and/or antenna beam tilt of
a downlink transmission from the micro cell base station is reduced to
unbalance the uplink and downlink micro cell boundaries. Alternatively,
the radio network controller may employ an offset value to mathematically
reduce mobile detected pilot power levels associated with the micro base
station.