Power control, broadly speaking, is the intelligent selection of transmitter power output in a communication system to achieve good performance within the system.
[1] The notion of "good performance" can depend on context and may include optimizing metrics such as link data rate, network capacity, outage probability, geographic coverage and range, and life of the network and network devices.
[2] The network devices supporting this feature include IEEE 802.11h Wireless LAN devices in the 5 GHz band compliant to the IEEE 802.11a.
The idea of the mechanism is to automatically reduce the used transmission output power when other networks are within range.
Because of the interference in the WCDMA system, power control plays a very important role in the quality control for the different services in the UMTS system.