Channel transmission quality feedback method, system and device

The invention discloses a channel transmission quality feedback method, a system and a device. The channel transmission quality feedback method comprises the following steps: signal-to-noise ratio of a sub-channel is selected according to a threshold to form a signal-to-noise ratio sub-vector, and the formed signal-to-noise ratio sub-vector is undertaken the non-linear conversion; the signal-to-noise ratio sub-sector after the non-linear conversion is polynomially fitted to obtain a feedback parameter, and the feedback parameter is transmitted and is used for ensuring that a transmitting end obtains the signal-to-noise ratio sub-vector so as to determine the channel transmission quality. Through the above method, the transmitting end utilizes the signal-to-noise ratio sub-vector to predict the variation of the signal-to-noise ratio sub-vector when different powers are adopted to improve factors and to predict the effective signal-to-noise ratio corresponding to different coding modulation ways as well as the