Patent ID: 6643343
Filing Date: 2003-11-04
Classification: H04L

Abstract:
A method for controlling a frequency of a voltage controlled oscillator, responsive to a received input signal that contains frames where, in at least some of said frames the input signal that contains frames where, in at least some of said frames, the input signal is a KS signal, at least in part carrying known information, carrying information in a spare constellation, or both, comprising the steps of:identifying received information signals contained in said KS signal in said at least some of said frames of said received input signal; determining sent symbols that resulted in said received information signals; rotating said received information signals in accordance with said sent symbols to form rotated signals; developing phase difference signals from said rotated signals; accumulating said phase difference signals to form an accumulated phase difference signal; and converting said accumulated phase difference signal to an analog form for application to said voltage controlled oscillator, where said step of developing phase difference signals computes a signal &PHgr;n through the equation &PHgr;n=tanâˆ’1(Bnâˆ’1/Anâˆ’1), or through an approximation equation &PHgr;n&ap;(Bnâˆ’1/Anâˆ’1), where Bn=Bnoâˆ’&Dgr;nÂ·Ano Bno=Bnâˆ’1+2âˆ’&lgr;(bnâˆ’Bnâˆ’1), An=Anoâˆ’&Dgr;nÂ·Bno, Ano=Anâˆ’1+2âˆ’&lgr;(anâˆ’Anâˆ’1), whereBn is an input at time frame n, Bnâˆ’1 is an input at time frame nâˆ’1, Bno is an output at time frame n, An is an input at time frame n, Anâˆ’1 is an input at time frame nâˆ’1, Ano is an output at time frame n, M is a number of identified information signals bn is a component of an identified received information signal, there being M such identified information signals, an is a second component of said identified received information signal there being M such identified information signals, &lgr; is a selected constant and &Dgr;n a step size that is a function of Bnâˆ’1.