[linux-dvb] Re: Troubles with DVB-C

["Robert Schlabbach" <robert_s@gmx.net>]

From: "Holger Waechtler" <holger@qanu.de>
> not entirely correct: http://en.wikipedia.org/wiki/Transponder
> Tronsponder is simply the term for a (re-)transmitter.

Actually, transponder is made up from the words "transmitter" and
"responder". This specifically described the behavior of communication
satellites, which "respond" to a signal by sending it back into the
direction it came from.

Cable headends and terrestrial transmitters may re-transmit the signals
they receive, but not in a "responding" fashion. Thus, I don't think the
term "transponder" appropriately describes the behavior of cable headends
or terrestrial transmitters.

> Since in the context of DVB the multiplexed and transmitted stream
> contains a description of the transmitter (and thus has to be
> remultiplexed for this particular transmission channel) the words
> "Multiplex", "Transponder" and "Transmitter" all describe a defined
> stream transmitted on a particular frequency in a network, no matter
> if you are talking about DVB-S, DVB-T or DVB-C.

I disagree. Only the term "multiplex" describes a defined stream, i.e. the
content rather than a transmission method or device. In contrast, the terms
"transponder", "transmitter" and "headend" describe devices which transmit
multiplexes. Different animals.

Regards,« 
-- 
Robert Schlabbach
e-mail: robert_s@gmx.net
Berlin, Germany