Method and apparatus for providing carrier synchronization in digital broadcast and interactive systems

摘要

An approach is provided for supporting carrier synchronization in a digital broadcast and interactive system (100). A carrier synchronization module (302) receives one or more signals representing a frame that includes a plurality of overhead fields (preamble and pilot blocks and multiple data segments separated by pilot blocks). The module (302) estimates carrier frequency and phase on a segment by segment basis and tracks frequency between segments. Carrier phase of the signal is first estimated based upon the overhead fields. Further estimates of carrier phase are determined based upon the estimated phase values from the overhead fields, and upon a random data field within the segment by means of a two-sweep PLL sweeping the segment of data from both the forward and reverse direction. Further, the frequency of the signal is estimated based upon the overhead fields. The above arrangement is particularly suited to a digital satellite broadcast and interactive system (100).