SHAPING THE FUTURE OF SATELLITE COMMUNICATIONS
8.3 Single Channel Per Carrier (SCPC) and Multiple
Channel Per Carrier (MCPC)
This section describes SCPC and MCPC two possibilities that can be used to
transmit data over satellite.
8.3.1 Single Channel Per Carrier
When using this option a single carrier is used at a fixed frequency and bandwidth.
A SCPC system is used when the satellite bandwidth is dedicated to a single
carrier (source).
8.3.2 Multiple Channel Per Carrier
When using this option several subcarriers are combined into a single stream
before they are modulated onto a carrier. This carrier is transmitted from a single
location to one or more remote sites. MCPC has the advantage to use the satellite
bandwidth more efficiently taking into account the maximum power (dB/Hz) allowed
by the satellite operator on the transponder.
8.4 Processing Modes
Newtec Elevation devices can operate in several processing modes to carry IP
data.
These processing modes indicate how the incoming data or signal is interfaced to
the modulator or demodulator and how it is transmitted over the modulated carrier.
The IP modulator/modem/demodulator supports:
• IP encapsulation into Transport Stream (TS) packets. This is done by first
encapsulating IP packets with protocol header (data piping/MPE/ULE) and
subsequently packing these variable-sized packets into fixed-size frames (DVB-S
TS). The TS packets are either converted to DVB-S or DVB-S2 symbols;
• IP encapsulation into DVB-S2 baseband frames. This is done by first
encapsulating IP packets with protocol header (XPE) and subsequently packing
these variable-sized packets into fixed-size frames (DVB-S2 BBF);
• Transparent forwarding of baseband frames to the satellite link. Transparent
forwarding means that the baseband frames are forwarded unmodified between
the Ethernet interface (GbE / Eth(ntS2BBF)) on one hand, and the satellite
interface on the other.
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