| 摘要 |
NTSC television signals are digitally encoded at sub-Nyquist rates by placing the alias components into those parts of the spectrum not normally occupied by the luminance or chrominance components of the video signal. In a system described, the sampling frequency, fs, is exactly 2fsc + 1/4fh or 2fsc - 1/4fh, where fsc is the NTSC color subcarrier frequency and fh is the line-scan frequency. Most of the alias signals in the thus encoded signal are removed from the baseband video by comb filtering between fs - fy and fv, where fv is the baseband video bandwidth.
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