METHOD AND APPARATUS FOR INCREASING THE QUALITY OF THE RECEIVER SYNCHRONIZATION OF QAM OR CAP MODULATED MODEM CONNECTION

摘要

The invention relates to am ethod and apparatus for improving the quality of receiver synchronization on QAM- or CAP- modulated modem connections having an adapative linear equalizer. The invention is based on the finding that in a QAM- or CAP-modulated data transmission system where the symbol rate and the average carrier frequency are in fixed relationship with each other, the vector (I, Q) formed by the In-phase (I) and the Quadrature (Q) component of the detector input signal rotates with the timing phase shift of the receiver. The quality of receiver synchronization is improved by utilizing information extracted from the vector rotation.