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Losses of PCR jitter in a multiplexing mode of an external transport stream (MPEG2 TS) and the encapsulated data without restamping are eliminated in the last version of IP/DVB encapsulator MediaSputnik 1102 series. Now jitter losses are practically equal to zero. It is very important achievement for such type of equipment, because it allows to "synchronize" asynchronous IP data and the synchronous external transport stream when section packing mode is on.
This process is realized as time base reestablishment of an external transport stream in the common multiplexed stream.
In the previous encapsulators releases the external transport stream was used only for data-transmission channels, at the same time the increased jitter did not influence on quality of TV channels, which are received by user's receivers. However during common DVB stream monitoring, with observance of standard ETR 290 requirements, the second level PCR accuracy pseudo-mistake took place. Actually the most important reason of jitter losses reduction researches is use of encapsulator in multiple access systems such as DVB-RCS. Zero jitter losses during the transparent multiplexing mode (without restamping) provide correct synchro data input into DVB stream for common synchronization of the TDMA satellite multiple access networks. In this case the encapsulator can provide complete support of multiple access network operation in a forward channel. It allows essentially reduce total cost of central part of HUB and improve system reliability as a whole. Control and monitoring modules (DVB-RCS table's oscillator and MPEG2 TS analyzer) also are including in encapsulator.
In the next versions of encapsulator, as the inter-network interface, it is planned to introduce protocol stack expansion modules (ATM, MPLS, etc.) and to improve a technological core for universal satellite multiple access systems, such as DVB-Overlay, DVB-CDMA, etc.
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