John Shutt wrote: > > Even with more frequent training signals, adapting for severe changes in > multipath is a recursive process that will span several training sequences. NO NO NO ... and if the training sequences are much closer together than 1/24 sec, interpolating between them becomes much, much easier and less computationally intensive. BIG HINT: you can not only extrapolate FORWARD from a training sequence, you can interpolate bewteen them (or even extrapolate backward!) if you wish. Just remember RECURSIVE ONLY IF YOU WNAT RECURSIVE!. Just because you were taught "recursive" in school does not mean it HAS to be recursive! > And the amount of data payload you eat up in the extra sequences brings your > total to something lower than the 1999 Sinclair Baltimore tests used for > DVB-T, Not necessarily. Certainly if you use much 2-VSB that happens ... but of course the same thing happens to DVB-T in robust modes. > > We would have been much better off switching to DVB-T in 1999, since we > would have ended up with as good or better multipath performance at a higher > data payload than A-VSB or E-VSB. > But at a SERIOUSLY increased power supply bill. DVB-T and other COFDM schemes are still inefficient due to pilots and guard intervals. A-VSB and like schemes add "pilots" but don't need guard intervals. Read my lips: guard intervals will eventually join the dodo. (And then, of course, COFDM will equal single carrier schemes ... there will be not much to choose between them.) Doug McDonald ---------------------------------------------------------------------- You can UNSUBSCRIBE from the OpenDTV list in two ways: - Using the UNSUBSCRIBE command in your user configuration settings at FreeLists.org - By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word unsubscribe in the subject line.