Patent ID: 7970080
Filing Date: 2011-06-28
Classification: H04L

Abstract:
1. A method of automated acquisition of a QAM signal said method employing a State machine progressing from an initial State to a final State; said State machine comprising: a symbol timing recovery loop; a carrier loop; a coarse frequency loop; and an equalizer; said method comprising: (A1) causing said State machine to enter a State AGC; (A2) performing a loop test for a AGC minimum Sub-State; (A3) performing a loop test for a AGC Lock Sub-State; (B) Performing a symbol timing recovery of said input QAM signal by adjusting a sampling clock of said symbol timing recovery loop; (C) Performing a Blind Equalization of said QAM signal without carrier lock to minimize a dispersion error of said received QAM signal constellation as compared with an error-free QAM signal constellation by adjusting a set of coefficients of said equalizer; (D) Performing a carrier recovery of said QAM signal to eliminate a residual carrier frequency error and to eliminate a phase error from said acquired QAM signal; and (E) Performing a decision directed equalization (DDE) of said QAM signal by updating a set of coefficients of said equalizer by using a decision based algorithm.