Method for receiving data and data receiver

A data receiver, comprising:

• a first receiving path, configured to receive a first transmission signal from a first channel, wherein the first receiving path comprises:
• a programmable gain amplifier, configured to adjust an intensity of the first transmission signal to generate an adjusted transmission signal according to an analog gain level;
• an analog to digital converter, configured to convert the adjusted transmission signal into a digital signal;
• an equalizer, configured to filter the digital signal to generate a filtered signal according to a set of filter coefficients;
• and
• a digital automatic gain control circuit, configured to adjust an intensity of the filtered signal according to a digital gain level;
• and
• a controller, coupled to the first receiving path and configured to:
• in a training mode, estimate a transmission condition of the first channel to generate an estimation result, and adjust the analog gain level and the digital gain level according to the estimation result, so as to obtain convergent values for the set of filter coefficients before the training mode ends;
• and
• in a data mode:
• perform a first gain adjustment operation to adjust the analog gain level and to correspondingly adjust the digital gain level according to the adjustment made to the analog gain level in the data mode.