what bitrate is sky broadcasting?

Question

what bitrate is sky broadcasting their normal sd movies at?

Answer 1

This depends on the channel. Some transponders are 27.5 Msps (Megasymbols per second) split between 10 channels, some are split between only 8 channels, and there are other transponders that transmit 22Msps and split it between only 6 channels. There are other variations but these are the most common with Sky. The 22Msps uses 5/6 FEC and the 27.5Msps ones use an FEC of 2/3. The Sky Movies channels for example are on a 27.5 Msps transponder with 8 channels. It is difficult to compare these bitrates to that of video streaming on a computer not only because of differing codecs, but also because internet communication is 2-way and can request retransmission of a missed packet. Satellite doesn't have this convenience and must send forward error correction which in a nutshell equates to transmitting the same thing several times along with information that will allow you to put missing pieces of the puzzle together without causing interruption. This increases the bitrate significantly.