Patent ID: 7173982

Claim:
A method of a digital frequency correction in a device, comprising: sampling a signal with a sampling cycle (k) and digitizing the sampled signal to produce a digitized signal (x(k)); processing an N-step Coordinate Rotation Digital Computer (CORDIC) algorithm so that a frequency of the digitized signal (x(k)) is altered at a predetermined frequency; representing the digitized signal (x(k)) by a first vector comprising a first in-phase component (i 0 ) and a first quadrature component (q 0 ) in a complex I/Q plane; imaging the first vector onto a second vector with a second in-phase component (I N ) and a second quadrature component (Q N ) by applying the N-step CORDIC algorithm to perform a vector rotation with a predetermined angle (z(k)), wherein the second vector represents a signal with an altered frequency and phase; and composing said predetermined angle (z(k)) of N different rotation angles (Î± n ), wherein each of the different rotation angles (Î± n ) are calculated according to arctan(2 âˆ’n ), n=0, 1, . . . , Nâˆ’1, and are respectively provided with a sign (Ïƒ n ) providing a direction of rotation.