Transmit Power Control
Transmit Power Control is a technical mechanism used within some networking devices in order to prevent too much unwanted interference between different wireless networks (e.g. the owner's network and the neigbour's network).
The network devices supporting this feature are Wireless LAN devices in the 5GHz band compliant to the IEEE 802.11a. The idea of the mechanism is to reduce automatically the used transmission output power when other networks are within range. Reduced power means reduced interference problems. The power level of a single device can be reduced by 6dB which should result in an accumulated power level reduction (the sum of radiated power of all devices currently transmitting) of at least 3dB (which is half of the power).