SYSTEM AND METHOD TO DETERMINE POWER CUTBACK IN COMMUNICATION SYSTEMS

摘要

A system and method are described for adaptively determining power cutback in communication system. A receiver determines noise on each sub-channel for different internal gain settings. It calculates what gain setting would be optimal from an SNR point of view and what power cutback value would lead to that gain setting. In a described embodiment, optimal power cutback in a communication device (10) is determined. Gain G [P] of the device is determined for each one of a plurality of device power levels P. Noise power N[i, P] is determined for each i tone of a plurality of downstream tones at each gain G [P]. Signal power S[j] is determined for each j tone of a plurality of tones in a received signal. An optimal power is determined for the device that maximize a utility function U[P] = sum_k log(l + (S[k] * tss[k, P] * G[P]) / N[k,P]), where k is a set of all downstream tones and tss[k, P] represents a ceiling-based power cutback.