| 摘要 |
PURPOSE: A digital TV receiver is provided to generate a lock up signal while recovering a symbol clock, and to use the generated lock up signal for initializing a carrier recovery, thereby recovering a carrier even though a frequency with a carrier signal disappears owing to a severe ghost noise. CONSTITUTION: An A/D converter(104) converts a VSB analog band pass signal into a digital band pass signal. A carrier recoverer(106) is initialized by a lock up signal, multiplies a reference carrier signal by the digital band pass signal, and converts into a digital baseband signal. A symbol clock recoverer(300) squares real-number/imaginary-number component signals of the digital baseband signal, respectively, adds the squared signals, detects a phase error of a symbol clock, and generates a frequency of a double symbol clock. If the phase error of the symbol clock is smaller than a half of a symbol clock period, a lock up signal generator(500) generates the lock up signal, and outputs the lock up signal to the carrier recoverer(106).
|
