| 摘要 |
In order to suppress interference signals from adjacent TV channels, an intermediate frequency signal is demodulated with a signal (S(fBT; 0°)) at a video carrier frequency into an in-phase signal, and with a signal (S(fBT; 90°)) shifted in phase by a phase angle pi/2 relative to the signal (S(fBT; 0°)) and at a video carrier frequency into a quadrature signal, for example, by an I/Q demodulator. The in-phase signal is filtered by a first Hilbert filter of a Hilbert filter pair having an even symmetrical impulse response in order to obtain a Hilbert-filtered in-phase signal. The quadrature signal is filtered by a second Hilbert filter of the Hubert filter pair having an uneven symmetrical impulse response in order to obtain a Hilbert-filtered quadrature signal. The Hilbert-filtered quadrature signal is added, for example, by an adder to the Hilbert-filtered in-phase signal in order to obtain a video output signal.
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