DIGITAL SYSTEM FOR BAND WIDTH REDUCTION OF VIDEO SIGNALS

1356090 Pulse radar NORTHROP CORP 18 July 1972 [4 Aug 1971] 33542/72 Heading H4D To reduce the bandwidth of video signals (e.g a pulse radar echo signal) for transmission to another point, the video signal is digitized, the digitized signal is converted from serial to parallel form, preselected groups of the parallel digital signals are delayed digitally by different predetermined amounts, and the delayed signals and a group of non-delayed signals directly from the serial-parallel conversion are placed in serial form distributed over a time cycle which is substantially longer than the duty cycle of the video signals (e.g. time cycle = 4 x duty cycle). The digital delay means may comprise two delay lines or a shift register, the serial-to-parallel converter may be a shift register and the analogue-to-digital converter may be a delta modulator.