A data-directed frequency-acquisition loop capable of generating a frequency error having a magnitude and direction from a double sideband suppressed signal comprises a first multiplier (410) that multiplies the signal by the output of a VCO (420). The output of the first multiplier (410) is convolved by a second multiplier (430). The I output of the second multiplier (430) passes through a first low-pass filter (440). The filtered I output and the Q output are then multiplied by a third multiplier (450). The output of the third multiplier is filtered through a second low-pass filter (460), amplified, and return to the VCO (420) to complete the feedback loop.
