Improved adjustment of transmission power in a communication system is provided. In one embodiment, in a point to multipoint communication system, transmission power of a subscriber unit is controlled based on power measurements made at a central access point. Power measurement information based on transmissions occurring at irregular intervals may be combined in a beneficial manner to control transmission output power. In one embodiment, a power regulation process determines a series of difference values indicating the differences between desired received power level at the central access point and measured received power level. A smoothing process is applied to the difference values. One or more parameters of the smoothing process vary with elapsed time since a last available power measurement.