METHOD AND APPARATUS FOR IMPROVING VERTICAL RESOLUTION OF NARROW BAND HIGH DEFINITION TELEVISION

摘要

High resolution television (HRT) information in the luminance signal Y of a composite video signal Y, I, Q, provided by vertically modulating the scan line at a high frequency (7.2 MHz) is synchronously detected (50) before transmittal to a display unit, modulated (52) at a lower frequency (1.2 MHz) within the bandwidth of the I signal at the phase of the a signal, and added (56) to the Q signal before transmittal. At the display unit, the high resolution information signal is synchronously detected and then remodulated at the same frequency and phase as the modulation of the scan at the signal source before it is added back into the luminance signal Y for display.