Special Settings - R&S SMCVB-K157 User Manual

®
R&S SMCVB-K157

3.4 Special settings

Access:
► Select "Baseband > DVB-C > Special".
The tab provides settings, that differ from the specification of the broadcast stan-
dard.
Settings different from the broadcast standard can be useful for research and develop-
ment. Applying these settings requires "Special Settings > On".
If you set a parameter different from the specification, the warning icon
to the left of the parameter.
Settings:
Special
Reed
Special Settings
Enables/disables special settings.
The setting allows you to switch between standard-compliant and user-defined channel
coding.
Remote command:
[:SOURce<hw>]:BB:DVBC[:SPECial]:SETTing[:STATe]
Reed Solomon
Enables/disables the Reed-Solomon encoder.
The standard stipulates a Reed-Solomon RS (204, 188), i.e. "Reed Solomon > On".
Incoming packets of the TS frame have a length of 188 bytes or, in special cases, a
length of 204 bytes. The packet length defines the behavior of the coder.
"On"
User Manual 1179.4686.02 ─ 01
Settings............................................................................................................ 22
Solomon.............................................................................................................. 22
●
"Packet Length = 188": The Reed-Solomon encoder adds
16 Reed-Solomon bytes to the incoming 188 bytes of an MPEG
transport stream frame. The Reed-Solomon decoder can correct
up to 8 erroneous bytes in a Reed-Solomon packet (= 204 bytes).
The number of incorrect bits in an errored byte is irrelevant.
●
"Packet Length = 204": Of the incoming 204 bytes of an MPEG
transport stream frame, the Reed-Solomon encoder overwrites
the last 16 bytes with its own Reed-Solomon bytes.
DVB-C configuration and settings
Special settings
on page 58
is displayed
22