| 摘要 |
PURPOSE: An apparatus for restoring carrier wave in a VSB receiving system is provided to accurately restore carrier waves without using a pilot signal. CONSTITUTION: A squarer(301) squares an I signal of a baseband to generate I and Q tone signals including information related to a frequency error by executing a non-linear operation to baseband I and Q signals. A multiplier(302) multiples the I signal by a Q signal. First and second high band filters(303a,303b) pass tone components only from output signals of the squarer and the multiplier, and remove DC components and noise components for outputting I and Q tone signals. A complex multiplier(304) transits I and Q tone signals of a radio frequency band into a baseband. Cosine and sine generators(305,306) generate cosine waves and sine waves corresponding to a position where tone is generated when no frequency error exists.
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