ATV/NTSC format converters

It is noted that up- and down-converters between advanced television (ATV) ad NTSC signals will be required for a simulcast service such as SC-HDTV (spectrum-compatible high-definition television). Down-conversion from ATV to NTSC is required at the transmitter to provide the simulcast NTSC program. Up-conversion is also required to integrate archival material into the ATV program, and in the dual-purpose ATV receiver which also receives NTSC programs. Filtering is a major part of the conversion process. The various theoretical and practical requirements for filtering are discussed, and a practical example is presented. Effects of signal sources and the NTSC format´s interlaced pickup and display on converter design are presented. A tutorial section on the use of three-dimensional transforms for study of conversion systems is appended