Patent attributes
An equalizer is used with complex modulation modems to reduce intersymbol interference. The equalizer includes an equalizer filter that receives an input data signal and adapts to compensate for the noisy communications channels to reduce intersymbol interference to the input signal. A branch metric computer demodulates the equalizer filter adapted input data signal. A decision device delivers an alpha value, starting phase information and confidence values from the demodulated input data signal. A gain determination function receives the confidence values and determines adaptation gain for the equalizer filter. A remodulator receives the alpha value and starting phase information and remodulates the alpha value and starting phase information into a remodulated data signal. A summing function compares the remodulated data signal to a delayed version of the input signal to generate an error signal for the equalizer filter to adjust the equalizer filter.
