Blind carrier phase synchronization for HDTV

Abstract

Vestigial sideband modulation is the modulation scheme of choice for the American standard for high-definition television (HDTV). The symbol-error rate of this modulation formal is highly dependent on the carrier phase estimation. Although a PLL tracks both carrier frequency as well as carrier phase in such a system, the residual phase noise needs further suppression. Phase synchronizers can either work in a data-aided manner or blindly. We focus on the latter and show the relationship between phase synchronization and blind source separation (BSS). A method suitable for the phase synchronization of VSB signals is presented and evaluated. Its performance is measured against that of the decision-directed approaches that have been suggested in the literature. Depending on the SNR of the VSB signal, either the blind or decision-directed approach exhibit superior performance. A semi-blind method, which combines the advantages of the decision-directed and the blind mode in their respective SNR regions, is introduced and set in perspective with the other algorithms.