Reply to thread

Message

<blockquote data-quote="2old4this" data-source="post: 4691" data-attributes="member: 174998">Symbol-rate is a measure of the quatity of digital information per unit time that is embedded in the microwave satellite signal.It's unit is MegaSymbols per second. It is analogous to the &quot;bit-rate&quot; used in computer terminology.Most receivers can process from about 2 to 40 or 45, though a few receivers are limited to a small range, or even - as is the case with the so-called Sky Digiboxes - limited to a few specific values.SCPC = Single Channel Per CarrierType of transmission where only a part of the available&nbsp; transponder is used for the signal, allowing the satellite operator to sell the remaining space on the transponder to other uplinkers. SCPC is typically used for feeds rather than for direct programming, and for some channels which are not really intended for mass consumption (eg directed at cable distributors). SCPC's advantage over MCPC is that the signals uplinked to the same transponder can be transmitted up to the&nbsp; &nbsp; satellite from different locations. MCPC = Multiple Channel Per CarrierAn average satellite transponder has a bandwidth of 27 MHz, sufficient for multiple video or audio channels to be transmitted simultaneously. MCPC uses a technique called Time Division Multiplex to transmit multiple programs, which works by sending data for one channel at a certain time and then data for another channel at another time. Many encoder manufacturers are currently experimenting with statistical multiplexing of MPEG-2 data. Using this technique, channels that need high data rate bursts in order to prevent pixelization of the picture, such as live sports events will obtain the bandwidth as they need it by reducing the data rate for other services that do not. Most receivers can process both SCPC and MCPC signals. Again, though, there are a few &quot;crippled&quot; receivers that can only process MCPC (and again, the Sky Digibox is one such example).See...http://www.coolstf.com/mpeg/index.html#srfechttp://www.mpeg2.net/home.html2old</blockquote>

[QUOTE="2old4this, post: 4691, member: 174998"] Symbol-rate is a measure of the quatity of digital information per unit time that is embedded in the microwave satellite signal. It's unit is MegaSymbols per second. It is analogous to the "bit-rate" used in computer terminology. Most receivers can process from about 2 to 40 or 45, though a few receivers are limited to a small range, or even - as is the case with the so-called Sky Digiboxes - limited to a few specific values. SCPC = Single Channel Per Carrier Type of transmission where only a part of the available transponder is used for the signal, allowing the satellite operator to sell the remaining space on the transponder to other uplinkers. SCPC is typically used for feeds rather than for direct programming, and for some channels which are not really intended for mass consumption (eg directed at cable distributors). SCPC's advantage over MCPC is that the signals uplinked to the same transponder can be transmitted up to the satellite from different locations. MCPC = Multiple Channel Per Carrier An average satellite transponder has a bandwidth of 27 MHz, sufficient for multiple video or audio channels to be transmitted simultaneously. MCPC uses a technique called Time Division Multiplex to transmit multiple programs, which works by sending data for one channel at a certain time and then data for another channel at another time. Many encoder manufacturers are currently experimenting with statistical multiplexing of MPEG-2 data. Using this technique, channels that need high data rate bursts in order to prevent pixelization of the picture, such as live sports events will obtain the bandwidth as they need it by reducing the data rate for other services that do not. Most receivers can process both SCPC and MCPC signals. Again, though, there are a few "crippled" receivers that can only process MCPC (and again, the Sky Digibox is one such example). See... http://www.coolstf.com/mpeg/index.html#srfec http://www.mpeg2.net/home.html 2old [/QUOTE]

Verification