Demodulating digital video broadcast signals

摘要

An apparatus for demodulating digital video broadcast signals comprising data modulated on a plurality of spaced carrier frequencies, comprising a transform circuit and a timing synchronization circuit. The transform circuit may be configured to analyze digital sample values. The timing synchronization circuit may be configured to synchronize the transform circuit with symbol periods of the broadcast signal. The timing synchronization circuit may be further configured to operate in (i) a first mode for analyzing the digital sample values over a relatively wide timing range to establish synchronization and (ii) a second mode for analyzing the digital sample values over a relatively narrow range about a synchronization point.