DIGITAL DEVICE FOR SEPARATION OF COLOR AND BRIGHTNESS SIGNALS IN SECAM DECODERS Russian patent published in 1994 - IPC

FIELD: television equipment. SUBSTANCE: device has analog-to-digital converter 1, unit 2 for separation of integral video signal into high-frequency and low- frequency constituents, two delay units 3, 6, adder 4, two digital-to analog converters 5, 18, subtraction unit 7, seven multipliers 8, 10, 15, 17, two tracing band-pass filters 9, 16, two frequency-modulated signal generators 11, 19, two signal differentiating circuits 12, 20, two control signal generators 13, 21, two frequency detectors of complex signals 14, 22. Frequency shift of high-frequency constituent of integral video signal as well as use of different methods for control of passing bands in tracing band-pass filters and introduced frequency feedback provide possibility to set optimal methods for change passing bands in color and brightness channels. These methods depend on size of frequency jumps in feedback circuits. This results in more effective separation of color and brightness signals. EFFECT: decreased distortion in brightness and color signals. 1 dwg