A distortion correction circuit comprises memory that stores N samples of
an input signal that occur at N different times, where N is an integer
greater than two. A self-receiver samples an output signal that is
generated by an RF power amplifier and that is based on said input
signal. A synchronization unit selects one of said N samples by comparing
said sampled output signal to said N samples. A predistortion unit
generates a distortion correction function based on said selected one of
said N samples and said output signal.