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Rohde & schwarz dvmd r&s MPEG2 measurement decoder
MPEG2 measurement decoder inputs: 2 serial, 1 parallel for ATSC and DVB standards
Key FactsPicture R&S DVMD MPEG2 Measurement Decoder
MPEG2 Measurement Decoder DVMD monitors and analyzes the MPEG2 transport stream. It indicates the contents and provides comprehensive information on the quality of the transport stream.
The combination of decoder and analyzer in one unit with conventional operating concept (no PC system) makes DVMD the waveform monitor of digital television. It is suitable for use wherever MPEG2 signals have to be checked.
Realtime measurements and simultaneous in-depth analysis yield extremely fast results. This makes DVMD an indispensable tool in development, in troubleshooting as well as in quality management and production.
Another important application is in the final inspection of MPEG2 signals before they leave the studio. While DVMD checks the video and audio signals at the output, error information is inserted directly into the decoded program (on-screen display).
Remote control capability allows integration into automatic monitoring networks. DVMD is thus ideal for network operators.
Complementary to Decoder DVMD, MPEG2 Measurement Generator DVG is offered for providing continuous MPEG2 transport streams made up of video, audio and data sequences in an endless loop.
The analyzer functions of DVMD comprise a protocol analysis of the measured MPEG2 transport stream in realtime.
For the north American ATSC standard, which is used for transmission via cable or terrestrial, there are not specific measurement guidelines existing. The realtime checks DVMD is performing in ATSC mode are therefore extensively according ETR290, where the different ATSC specific system and program information tables (PSIP) are concerned.
Any error occurring is directly indicated by front-panel LEDs. DVMD also detects sporadic errors. Moreover it provides error statistics showing how often a particular type of error has occurred within a specified time interval. A list (REPORT; see lower figure) giving detailed information on the errors occurred including date and time can be obtained. The list contains up to 1000 entries and may be edited to cover exclusively a single type of error.
An integrated monitoring facility allows upper/lower limit checking of the data rates of the null packets. This assures identifying a program or other service being lost from the mutliplex.
If there is an error, the trigger/capture facilities of DVMD can be used to freeze part of the transport stream affected by the error (approx. 2 Mbit) and output it via the RS232 interface in order to analyze it down to bit level.
In addition to in-depth analysis, the optional Stream Explorer DVMD-B1 software allows further online masurements with graphic display on the screen (eg data rates, PCR jitter, etc).
R&S DVMD MPEG2 Measurement Decoder Features
An MPEG2 transport stream usually consists of a number of programs which may contain video, audio and data streams (elementary streams). DVMD decodes a video and an audio stream from the selected program. The decoded video signal is simultaneously output in CCVS, analog Y/C and digital serial ITU-R601 formats.
s analog stereo signals and as digital AES/EBU signals.
The following formats can be decoded by DVMD:
* Video: MainR&S DVMD MPEG2 Measurement Decoder Features
Error report with detailed information on causes of errors
profile at main level (MP@ML - SDTV)
* Audio: MPEG1 Layer 1 & 2, MPEG2 Layer 1 & 2 with low sampling rate
R&S DVMD MPEG2 Measurement Decoder Features
List of all programs in the transport stream
List of all elementary streams in a selected program
