HIGH-DEFINITION TELEVISION SIGNAL PROCESSING SYSTEM AND HIGH-DEFINITION TELEVISION SIGNAL RECEIVING SYSTEM (DESIGN VERSIONS)

摘要

FIELD: high- definition television systems. SUBSTANCE: high-definition television system compatible with NTSC with respect to frequency band uses multiple quadrature modulation. First quadrature modulation blanked carrier is modulated by high-priority information primarily including low-frequency information. Second quadrature modulation blanked carrier is modulated by low-priority information primarily including high-frequency information. High-priority quadrature-modulated signal has higher amplitude and narrower frequency band than low-priority quadrature-modulated signal and occupies lower part of frequency spectrum of multiple quadrature- modulated signal usually occupied by blanked sideband of NTSC standard television signal. Frequency spectrum of multiple quadrature-modulated signal is characterized by signal blanking at frequencies associated with high-energy information in standard NTSC signal, such as at frequencies close to NTSC image and sound carriers. EFFECT: reduced cross-talk from standard and HF current signals. 34 cl, 5 dwg