A Proposal for Compatibly Improving the Scrambling of SMPTE 259M

A method has been devised which will inhibit the generation of pathological serial digital signals or other serial signals with poor statistics which adversely affect clock recovery and cable equalization. This is accomplished by adaptively dithering the LSB of certain video words only when such a pattern of poor statistics would otherwise occur. LSB dither will not be visible on picture monitors. Furthermore, the dither will occur very infrequently. A complementary descrambler has been developed which will reverse the dither when it occurs. The circuitry which accomplishes these goals is simple. There is no additional time delay introduced by the improved scrambling algorithm. The primary advantage of this system is that the serial digital signal is made much more robust.

Published

1995-02

Content type

Original Research

DOI

10.5594/M00826

ISBN

978-1-61482-922-5