5
EMA x08/407
Part N
o
: 917x.xx
ENCODER/ MULTIPLEXER
ASI / SDI/ A/V
→
ASI(TS) & IP(TS)
ASI / HDMI
→
ASI(TS) & IP(TS)
A
LINE
Up to four input signals are encoded at each device and fed-in the output transport stream. The ASI interface transmits the output
signal as a DVB transport stream according to ISO 13818-1 [5] at a maximum data rate of 214 Mbps. The signal can be sent either to a
cascaded EMA or to a downstream modulator. By cascading EMA devices (up to 8), a transport stream with up to 32 services can be
produced or these services can be added to an incoming transport stream.
The ASI input port processes a transport stream signal at a maximum rate of 214 Mbps. If the transport stream provides enough
transmission capacity, the encoded A/V signals are embedded via the integrated multiplexer according to the DVB standard.
The output signal contains all required program tables and associated services (PAT, PMT and SDT). A NIT is generated but will not
contain any network-specific information. A subsequent modulator adjusts the adaptation of the NIT.
1.4 Multiplexer/ Re-multiplexer/ PID filter
For processing the incoming ASI transport stream a multiplexer has been integrated into the EMA device. On condition that the
transport steam provides enough transmission capacity, or additional transport volume is achievable by raising the transport stream
bitrate, new services and/ or program components can be added.
Depending on the configuration of the 4 input interfaces, the analogue or digital A/V signals (SDI) will be converted into DVB data and
pooled to a standard DVB signal or added to the DVB transport stream being forwarded.
The parameters necessary for the input interfaces and the transport stream parameters have been pre-set at the factory (
»
section 3.2).
See section 3.3.4 for details of how EMA cascade systems using multiple devices are brought into use and how the transport stream
can be manipulated from the HTML user interface.
