Abstract: A method and apparatus for reducing the phase noise introduced by pointer justification from a synchronous digital hierarchy network in a transmitted numerical signal. In the method and apparatus, occasional redundancies associated with bit justifications and fixed redundancies are combined with occasional prefiltered redundancies associated with the pointer justifications, and the combined signal is filtered in an analog phase locked loop. The occasional redundancies associated with the pointer justifications and at least part of the fixed redundancies with or without bit justifications are prefiltered in two stages, and the prefiltered signals are combined with the occasional redundancies associated with the bit justifications whenever these occasional redundancies are not prefiltered.

Abstract: A system and related multiplexers/demultiplexers for the transmission/reception of digital television information (video+audio), including high definition information (HDTV). Such transmission typically occurs in packets at various work speeds including, among others, a special transmission in which two data flows are transmitted simultaneously to obtain a single information. The multiplexer is associated with external buffers that receive the data at different speeds, form the packet and generate requests of transmission to the multiplexer that receives them according to preestablished priorities.