Robert Louis Cupo

A New NTSC Co-Channel Interference Rejection Filter with Coded 6-VSB Modulation for Improved ATV Coverage

The Advanced Television Systems Committee (ATSC) advanced television (ATV) standard and its service area predictions assume the use of a comb filter at the receiver However, such a filter is not required by the ATV standard. There are also unresolved questions about the efficacy of the comb filter. We describe a new system, including an NTSC co-channel interference rejection filter with coded 6-level digital vestigial sideband (6-VSB) modulation, of comparable complexity, which offers improved ATV service area. Coverage analysis results demonstrate that the system provides much better co-channel performance today, with a comparable carrier-to-noise (C/N) threshold and better threshold performance when NTSC transmission ceases in the future. The new system obviates concerns about the reliability of the comb filter under conditions of noise, interference, and multipath.