Patent ID: 7092453

Claim:
Method to adaptively control the phy mode of the transmissions from a peripheral station to a master station in either a point-to-multipoint or point-to-point transmission system with automatic transmit power control, called ATPC, and comprising the steps of: receiving, at the peripheral station, power control signaling messages from the master station and regulating the transmitted power; receiving, at the peripheral station, phy mode switching messages from the master station and changing the phy mode of the transmission; transmitting said power control signaling messages from the master station to keep the received power inside an ATPC range; transmitting a phy mode switching message from the master station in case the received power level reaches either a lower or a higher switching threshold associated with each phy mode used by the peripheral station for its transmissions, in order to command switching from a less robust and more efficient phy mode to a more robust and less efficient phy mode, or vice versa, in a way to establish a hysteresis cycle between said switching thresholds; transmitting said power control signaling messages from the master station in order to keep the received mean power substantially close to a reference received power level or working point predefined for each phy mode; checking if the peripheral station has sufficient available transmission power in order to guarantee the transmission using said less robust phy mode with such a power level that allows the master station to receive the transmitted signal above the working point of said less robust phy mode; and transmitting in case the check is affirmative a phy mode switching message towards a less robust and more efficient phy mode.