| 摘要 |
<p>FULLY COMPATIBLE HIGH DEFINITION TELEVISION A fully compatible high definition signal, which can still be received with conventional resolution by conventional TV receivers without auxiliary apparatus is provided by the present invention. One TV channel carries the conventional TV signal while high frequency luminance and chrominance information is provided in a second TV channel. The baseband signal containing the high frequency components is derived from the lower sideband output of a product modulator whose inputs are taken from an anti-alias filtered (camera) source of wideband luminance information and a local oscillator whose frequency is a multiple of the conventional chrominance subcarrier frequency embedded in the conventional baseband signal for the other channel. Band-limited portions of the high-frequency chrominance information are multiplexed between alternate horizontal lines and modulated by a signal which is, effectively, an odd multiple of one-quarter the line rate to provide a single sideband spectrum that non-interferingly interleaves the high frequency luminance spectra.</p> |
