Digital Radio Central - Sponsored by TSS Radio
  DRC Home Page DRC Forums Contact Us  
SIRIUS Backstage Forum
  Sirius Satellite Radio XM Satellite Radio iTunes/iPod Slacker Pandora  
FAQ Members List Calendar Search Today's Posts Mark Forums Read  
Go Back   SIRIUS Backstage Forum > >
Visit Digital Radio Central


Galaxy Nation Explore the other side of the universe. Discuss AM/FM, XM, DISH, DirecTV, HD Radio, and all mp3 players. Here you can also discuss the ins and outs of tomorrow's radio technology...where music and satellites collide. Who said it's not rocket science?!?

Thread Tools Display Modes
Old 01-28-2007, 04:55 PM   #16
Sirius Star
leviramsey's Avatar
Join Date: May 01, 2004
Location: Springfield, MA
Posts: 1,186
leviramsey is on a distinguished road

The only statements [I've read/heard/etc.] that Sirius doesn't use dynamic bitrate allocation have been from various board posters (many of whom, based on posting history, are advocates for XM, which has been proven to use static bitrate allocations).

OTOH, there is evidence that Sirius has the ability now to dynamically allocate bits between channels (essentially statistical multiplexing). There's a patent issued to Lucent from the mid-to-late-'90s, prior to when the encode/decode system would reasonably have been finalized, that covers how to do it with the PAC codec (with certain indications from the patent documentation that, at least to my reading, indicate that dynamic allocation was a major selling point of the PAC codec for digital audio broadcasting applications). There's also a Crutchfield article from 2003 or 2004, a tour of Sirius' equipment and facilities, that includes a photo of hardware that's described as performing the dynamic allocations.

It could be that Sirius is not taking advantage of dynamic allocations now. For instance, they may have been using it and found that the allocation algorithms (which fundamentally rest on determining the relative compressibility of each channel which is not that trivial) weren't at a point to where they were giving appreciably better SQ. It's also possible that some of the enhancements that Sirius made to the PAC codec removed the possibility of dynamic allocation.
In the dog days, people look to Sirius.

Howard 99: What Came Before Howard 100!
Previous Track: The home of even-later classic rock
'90s Download: All the hits of the '90s
leviramsey is offline  

Go Back   SIRIUS Backstage Forum > >

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 07:20 PM.
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Search Engine Optimisation provided by DragonByte SEO v2.0.39 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
All Content Copyright SIRIUS Backstage. All Rights Reserved. SIRIUS and registered trademarks are the property of SIRIUS Satellite Radio, Inc. The opinions posted on SIRIUS Backstage website and forums are those of the individual posters and/or this website and are not necessarily the opinions or positions of SIRIUS Satellite Radio, Inc.