Crosstalk Reduction in the Digital Audio Signals using Quadrature Modulation of the TV Carrier and a Reference Signal used for Quadrature Multiplexing

Abstract

A digital audio signal transmission system that implements quadrature modulation for video carriers is examined for use in 2nd generation EDTV (Enhanced TV) systems.
Interference between audio and video signals, caused by the multiplex transmission of terrestrial broadcasting, is paid special attention to.
To improve the receiving quality of digital audio signals, reducing the crosstalk between video signals and the multiplexed signals is considered. Experiments show that using a two-dimensional waveform equalizer in conjunction with a line comb filter effectively reduces interference.
Reference signals used for quadrature multiplexing sent from broacasting stations are also studied. Results show that interference occurring in 8-field sequence GCR signal processing can be reduced by using a 4-field sequence sinX/X signal delayed by one-data period.