Phase-jitter compensation using periodic harmonically related components

摘要

A quadrature amplitude-modulated (QAM) data signal receiver employs a phase compensation arrangement (16, 31, 33) before the equalizer (17). The arrangement utilizes the assumption that the frequency components typically present in the phase perturbance are power-line related. This enables an effective phase compensator to be of relatively low complexity compared to the equalizer (17). Since the compensator is "pretuned", only the phase and amplitude of the frequency components need be adaptively found. This makes for a relatively stable arrangement with a suitable convergence rate. In an alternative arrangement, a phase compensator (216, 233, 240) is provided for use after the equalizer (217).