A power control system includes a transmitter having a plurality of gain-adjustable elements, a switchable attenuator located at an output of the transmitter, a gain-adjustable power amplifier coupled to the attenuator, and a power control element responsive to a power target signal, the power control element configured to calculate and apply a gain control signal to the plurality of gain-adjustable elements in the transmitter, to the switchable attenuator, and to the gain-adjustable power amplifier so that a signal to noise ratio (SNR) at the output of the transmitter remains substantially constant over a range of output power.